GCA XPress 05.3 - OcCC

proclimweb.scnat.ch

GCA XPress 05.3 - OcCC

Global Change Abstracts

The Swiss Contribution

May 2005 – August 2005

Published and

distributed by:

Editor: Gabriele Müller-Ferch

Editorial staff: Eveline Zbinden

ProClim–

Tel: (41 31) 328 23 23

Fax: (41 31) 328 23 20

e-mail: mueller@scnat.ch

Source: Science Citation Index®

Social Science Citation Index®

Institute for Scientific Information®

Circulation: 1000

ProClim– Forum for Climate and Global Change

Schwarztorstr. 9, 3007 Bern, Switzerland

www.proclim.ch

Printed by: Druckzentrum Vögeli AG, Langnau

ISBN Number: 978-3-907630-15-0

Issue: GCA 05/3, October 2005, Berne, Switzerland


Contents

Foreword 5

Methods and Statistics 6

Short List of all Abstracts 8

Abstracts

1 Earth System Process Studies and Methodologies 19

1.1 Atmosphere 19

1.2 Terrestrial Ecosystems 30

1.3 Soil and Litosphere 48

1.4 Cryosphere 50

1.5 Oceans and Fresh Water Systems 55

1.6 Energy Balance 63

1.7 Coupled Systems and Cycles 65

2 Past Global Changes 69

3 Human Dimensions 80

4 Mitigation and Adaptation Technologies 85

5 General Topics 88

Index of Authors 92

Index of Disciplines 102

SciSearch® - Science Citation Index® 104

Global Change Abstracts – The Swiss Contribution 3


Foreword

Reviewed journal articles - a scientific link to the world

Publications in peer-reviewed journals are just one form for the dissemination of research results.

Why then puts ProClim- so much emphasis on the Global Change Abstracts? One important task of

ProClim- (and of the Academy of Sciences) is to foster international collaboration and the reputation of

Swiss research. To improve Swiss recognition, publication in internationally accessible journals is unavoidable.

The prestigious international assessment activities such as IPCC 5 or the Millennium assessment

include only results that are published in peer reviewed journals. It is evident that the authors

of the assessments are to fulfill the same criteria. The same holds for scientists who wishto enter

into research cooperations via the international research programs WCRP 1 , IGBP 2 , IHDP 3 and DI-

VERSITAS 4 .

For this reason ProClim distributes the Global Change Abstracts to key research program offices

worldwide. In addition the same list of publications is accessible on the ProClim-Webpage. This has

proven to be helpful not only for journalists to find out more about a scientist but also for the ProClim

office, when trying to identify specific experts. You find the publications of different persons under

www.proclim.ch/persons.html or sorted by topic under www.proclim.ch/publications.html .

Since climate and global change is of great importance for the entire society, the science community

needs to go beyond publication in peer reviewed journals and enter into a dialog with decision makers.

ProClim and the OcCC (Advisory Body on Climate Change) offer many other instruments to support

these activities.

1 WCRP (World Climate Research Programme

2 IGBP (International Geosphere Biosphere Programme)

3 IHDP (International Human Dimensions Programme on Global Environmental Change)

4 DIVERSITAS (International Programme on Biodiversity Sciences)

5 IPCC (Intergovernmental Pannel on Climate Change)

Global Change Abstracts – The Swiss Contribution

5


Methods and Statistics

Global Change Abstracts: The Swiss Contribution (GCA) is a compendium of abstracts for papers on

the topic of global environmental change. The abstracts are written or co-authored by Swiss scientists

and other experts working in Switzerland. The papers are published in one of the 6000 journals covered

by the databases Science Citation Index® and Social Sciences Citation Index®, which are compiled by

the Institute for Scientific Information®.

We use three different searches to identify the papers in Global Change Abstracts, namely: (i) a search

in both databases mentioned above for the names of the principal investigators and their coworkers contained

in the ProClim- Infosystem (about 700 names) or for projects with Switzerland as a country of origin;

(ii) a search for additional Swiss papers that have been published in a selection of journals chosen

from the Science Citation Index® based on the themes they cover (using “journal catagory codes” assigned

by the database producer); (iii) a search in the database Social Sciences Citation Index® for

Swiss papers in the social sciences that contain one of over 50 keywords on the topic of global change.

ProClim- staff then scan these selected papers to determine which are relevant for inclusion in Global

Change Abstracts.

You can also find all papers published in Global Change Abstracts on the ProClim- WWW site at

http://www.proclim.ch/Publications.html. On this site you will find a database including all Swiss articles

of the GCAs and in addition selected articles relevant for climate and global change research published

in journals like Nature, Science or Ambio.

If you are interested in ordering a copy of a paper quoted in this issue, you can get further information

in the ProClim- database, for example the address of the first author. A double click on the selected article

will show you more detailed information not printed in the following document.

A total of 205 papers that were published during the period May - August 2005 are included in this

issue. These papers are classified according to the following categories, which are also used to order

the abstracts in GCA (refer to the Table of Contents):

1 Earth system process studies and methodologies

1.1 Atmosphere

1.2 Terrestrial Ecosystems

1.3 Soil and Lithosphere

1.4 Cryosphere

1.5 Ocean/Fresh Water Systems

1.6 Energy Balance

1.7 Coupled Systems and Cycles

2 Past Global Changes

3 Human Dimensions

4 Mitigation and Adaptation Technologies

5 General Topics

The papers are also referenced by an alphabetical list of authors and by scientific discipline

(as preassigned by the Institute for Scientific Information®).

If you think a paper should be published in an issue of the Global Change Abstracts, you can send it to

ProClim- and we will consider including it in a future issue.

We hope that Global Change Abstracts: The Swiss Contribution will facilitate the exchange of

information and with it the interdisciplinarity among the global change research community.

6 Global Change Abstracts – The Swiss Contribution


Number of abstracts

50

40

30

20

10

0

METHODS AND STATISTICS

1.1 1.2 1.3 1.4 1.5 1.6 1.7 2 3 4 5

Category

Fig. 1 Histogram showing the thematic distribution of abstracts included in this issue (GCA 05/3)

Global Change Abstracts – The Swiss Contribution

7


1 Earth System Process Studies and Methodologies 19

1.1 Atmosphere 19

Long-range transport to Europe: Seasonal variations and implications for the European ozone budget (05.3-1)

Auvray M, Bey I

Trace metals in ambient air: Hourly size-segregated mass concentrations determined by Synchrotron-XRF

(05.3-2)

Bukowiecki N, Hill M, Gehrig R, Zwicky C N, Lienemann P, Hegedus F, Falkenberg G, Weingartner E,

Baltensperger U

The influence of south foehn on the ozone mixing ratios at the high alpine site Arosa (05.3-3)

Campana M, Li Y S, Staehelin J, Prevot A S H, Bonasoni P, Loetscher H, Peter T

Statistical analysis of the vehicle pollutant emissions derived from several European road tunnel studies

(05.3-4)

Colberg C A, Tona B, Catone G, Sangiorgio C, Stahel W A, Sturm P, Staehelin J

Black carbon ageing in the Canadian Centre for Climate modelling and analysis atmospheric general

circulation model (05.3-5)

Croft B, Lohmann U, von Salzen K

Two independent methods for mapping bulk deposition in France (05.3-6)

Croise L, Ulrich E, Duplat P, Jaquet O

The performance of RAMS in representing the convective boundary layer structure in a very steep valley

(05.3-7)

de Wekker S F J, Steyn D G, Fast J D, Rotach M W, Zhong S

Middle Atmospheric Water Vapour Radiometer (MIAWARA): Validation and first results of the LAPBIAT Upper

Tropospheric Lower Stratospheric Water Vapour Validation Project (LAUTLOS- WAVVAP) campaign (05.3-8)

Deuber B, Ilaefele A, Feist D G, Martin L, Kämpfer N, Nedoluha G E, Yushkov V, Khaykin S, Kivi R, Vomel H

The use of geographic information systems in climatology and meteorology: COST 719 (05.3-9)

Dyras I, Dobesch H, Grueter E, Perdigao A, Tveito O E, Thornes J E, van der Wel F, Bottai L

Chemistry-climate model SOCOL: a validation of the present-day climatology (05.3-10)

Egorova T, Rozanov E, Zubov V, Manzini E, Schmutz W, Peter T

Stratospheric water vapor predicted from the Lagrangian temperature history of air entering the stratosphere

in the tropics (05.3-11)

Fueglistaler S, Bonazzola M, Haynes P H, Peter T

A new method to link PM10 concentrations from automatic monitors to the manual gravimetric reference

method according to EN12341 (05.3-12)

Gehrig R, Hueglin C, Schwarzenbach B, Seitz T, Buchmann B

Climate-based site selection for a very large telescope using GIS techniques (05.3-13)

Graham E, Sarazin M, Beniston M, Collet C, Hayoz M, Neun M, Casals P

NOAA AVHRR derived aerosol optical depth over land (05.3-14)

Hauser A, Oesch D, Foppa N, Wunderle S

Do aircraft black carbon emissions affect cirrus clouds on the global scale? (05.3-15)

Hendricks J, Karcher B, Lohmann U, Ponater M

Climatology of mountain venting-induced elevated moisture layers in the lee of the Alps (05.3-16)

Henne S, Furger M, Prevot A S H

Modeling the influence of intermittent rain events on long-term fate and transport of organic air pollutants

(05.3-17)

Jolliet O, Hauschild M

A composite study on the structure and formation of ozone miniholes and minihighs over central Europe

(05.3-18)

Koch G, Wernli H, Schwierz C, Staehelin J, Peter T

8

Short List of all Abstracts

Global Change Abstracts – The Swiss Contribution


SHORT LIST OF ALL ABSTRACTS

Design and field application of an automated cartridge sampler for VOC concentration and flux

measurements (05.3-19)

Kuhn U, Dindorf T, Ammann C, Rottenberger S, Guyon P, Holzinger R, Ausma S, Kenntner T, Helleis F,

Kesselmeier J

Importance of submicron surface-active organic aerosols for pristine Arctic clouds (05.3-20)

Lohmann U, Leck C

A debiased ranked probability skill score to evaluate probabilistic ensemble forecasts with small ensemble

sizes (05.3-21)

Müller W A, Appenzeller C, Doblas Reyes F J, Liniger M A

Adaptation of dry nephelometer measurements to ambient conditions at the Jungfraujoch (05.3-22)

Nessler R, Weingartner E, Baltensperger U

Changes of daily surface ozone maxima in Switzerland in all seasons from 1992 to 2002 and discussion of

summer 2003 (05.3-23)

Ordonez C, Mathis H, Furger M, Henne S, Huglin C, Staehelin J, Prevot A S H

Atmospheric response to NOy source due to energetic electron precipitation (05.3-24)

Rozanov E, Callis L, Schlesinger M, Yang F, Andronova N, Zubov V

The heterogeneous interaction of HOCl with solid KBr substrates: The catalytic role of adsorbed halogens

(05.3-25)

Santschi C, Rossi M J

Trends of heavy precipitation and wet and dry spells in Switzerland during the 20th century (05.3-26)

Schmidli J, Frei C

Special characteristics of the temperature structure near the surface (05.3-27)

Sodemann H, Foken T

An airborne radiometer for stratospheric water vapor measurements at 183 GHz (05.3-28)

Vasic V, Feist D G, Müller S, Kämpfer N

Generation of submicron Arizona test dust aerosol: Chemical and hygroscopic properties (05.3-29)

Vlasenko A, Sjogren S, Weingartner E, Gäggeler H W, Ammann A

Nitric Acid Trihydrate (NAT) formation at low NAT supersaturation in Polar Stratospheric Clouds (PSCs) (05.3-30)

Voigt C, Schlager H, Luo B P, Dornbrack A D, Roiger A, Stock P, Curtius J, Vossing H, Borrmann S, Davies S,

Konopka P, Schiller C, Shur G, Peter T

Integrated equivalent latitude as a proxy for dynamical changes in ozone column (05.3-31)

Wohltmann I, Rex M, Brunner D, Mader J

1.2 Terrestrial Ecosystems 30

Responses of net ecosystem CO2 exchange in managed grassland to long- term CO2 enrichment, N

fertilization and plant species (05.3-32)

Aeschlimann U, Nösberger J, Edwards P J, Schneider M K, Richter M, Blum H

Are ecological compensation areas attractive hunting sites for common kestrels (Falco tinnunculus) and

long-eared owls (Asio otus)? (05.3-33)

Aschwanden J, Birrer S, Jenni L

Carabid assemblages in agricultural landscapes: impacts of habitat features, landscape context at different

spatial scales and farming intensity (05.3-34)

Aviron S, Burel F, Baudry J, Schermann N

Behavioral constancy for interspecies dependency enables Nearctic Chymomyza amoena (Loew)

(Diptera : Drosophilidae) to spread in orchards and forests in Central and Southern Europe (05.3-35)

Band H T, Bachli G, Band R N

Diversity and genetic structure of the wood ant Formica lugubris in unmanaged forests (05.3-36)

Bernasconi C, Maeder A, Cherix D, Pamilo P

Simulating complex landscapes with a generic model: Sensitivity to qualitative and quantitative classifications

(05.3-37)

Bolliger J

Global Change Abstracts – The Swiss Contribution 9


Simulating the spatial and temporal dynamics of landscapes using generic and complex models (05.3-38)

Bolliger J, Lischke H, Green D G

Ranking protected areas in the Azores using standardised sampling of soil epigean arthropods (05.3-39)

Borges P A V, Aguiar C, Amaral J, Amorim I R, Andre G, Arraiol A, Baz A, Dinis F, Enghoff H, Gaspar C, I

lharco F, Mahnert V, Melo C, Pereira F, Quartau J A, Ribeiro S P, Ribes J, Serrano A R M, Sousa A B,

Strassen R Z, Vieira L, Vieira V, Vitorino A, Wunderlich J

Persistent organic pollutants in source-separated compost and its feedstock materials - A review of field

studies (05.3-40)

Brändli R C, Bucheli T D, Kupper T, Furrer R, Stadelmann F X, Tarradellas J

Surface runoff and transport of sulfonamide antibiotics and tracers on manured grassland (05.3-41)

Burkhardt M, Stamm C, Waul C, Singer H, Müller S

The effect of slug grazing on vegetation development and plant species diversity in an experimental

grassland (05.3-42)

Buschmann H, Keller M, Porret N, Dietz H, Edwards P J

Phytophenological trends in the Swiss Alps, 1951-2002 (05.3-43)

Defila C, Clot B

Model-based stratifications for enhancing the detection of rare ecoligical events (05.3-44)

Edwards T C, Cutler D R, Zimmermann N E, Geiser L, Alegria J

Differences in surface roughness, energy, and CO2 fluxes in two moist tundra vegetation types, Kuparuk

watershed, Alaska, USA (05.3-45)

Eugster W, Mcfadden J P, Chapin F S

Survival and growth responses of Populus nigra, Salix elaeagnos and Alnus incana cuttings to varying levels

of hydric stress (05.3-46)

Francis R A, Gurnell A M, Petts G E, Edwards P J

Mycorrhizas improve nitrogen nutrition of Trifolium repens after 8 yr of selection under elevated atmospheric

CO2 partial pressure (05.3-47)

Gamper H, Hartwig U A, Leuchtmann A

A test of the tree-line carbon limitation hypothesis by in situ CO2 enrichment and defoliation (05.3-48)

Handa I T, Körner C, Hättenschwiler S

Effect of ecological compensation areas on floristic and breeding bird diversity in Swiss agricultural

landscapes (05.3-49)

Herzog F, Dreier S, Hofer G, Marfurt C, Schüpbach B, Spiess M, Walter T

Predicting when animal populations are at risk from roads: an interactive model of road avoidance behavior

(05.3-50)

Jaeger J A G, Bowman J, Brennan J, Fahrig L, Bert D, Bouchard J, Charbonneau N, Frank K, Gruber B,

von Toschanowitz K T

The enemy release and EICA hypothesis revisited: incorporating the fundamental difference between

specialist and generalist herbivores (05.3-51)

Joshi J, Vrieling K

Modeling avian abundance from replicated counts using binomial mixture models (05.3-52)

Kery M, Royle J A, Schmid H

Taking the fungal highway: Mobilization of pollutant-degrading bacteria by fungi (05.3-53)

Kohlmeier S, Smits T H M, Ford R M, Keel C, Harms H, Wick L Y

Relative importance of resource quantity, isolation and habitat quality for landscape distribution of a

monophagous butterfly (05.3-54)

Krauss J, Steffan Dewenter I, Müller C B, Tscharntke T

Effect of microsites, logs and ungulate browsing on Picea abies regeneration in a mountain forest

(vol 205, pg 251, 2005) (05.3-55)

Kupferschmid A D, Bugmann H

Responses of deciduous forest trees to severe drought in Central Europe (05.3-56)

Leuzinger S, Zotz G, Asshoff R, Körner C

Year-round measurements of net ecosystem CO2 flux over a montane larch forest in Mongolia (05.3-57)

Li S G, Asanuma J, Kotani A, Eugster W, Davaa G, Oyunbaatar D, Sugita M

10

Global Change Abstracts – The Swiss Contribution

SHORT LIST OF ALL ABSTRACTS


SHORT LIST OF ALL ABSTRACTS

Influence of myristic acid supplementation on energy, fatty acid and calcium metabolism of sheep as affected

by dietary calcium and forage : concentrate ratio (05.3-58)

Machmüller A, Kreuzer M

Forest storm damage is more frequent on acidic soils (05.3-59)

Mayer P, Brang P, Dobbertin M, Hallenbarter D, Renaud J P, Walthert L, Zimmermann S

An experimental test of the evolution of increased competitive ability hypothesis in goldenrod, Solidago

gigantea (05.3-60)

Meyer G, Clare R, Weber E

Ectomycorrhizas and mast fruiting in trees: linked by climate-driven tree resources? (05.3-61)

Newbery D M

Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody

plant species (05.3-62)

Novak K, Schaub M, Fuhrer J, Skelly J M, Hug C, Landolt W, Bleuler P, Kräuchi N

Glomus badium, a new sporocarpic mycorrhizal fungal species from European grasslands with higher soil pH

(05.3-63)

Oehl F, Redecker D, Sieverding E

Carbon dioxide regime, species identity and influence of species initial abundance as determinants of change

in stand biomass composition in five-species communities: an investigation using a simplex design and

RGRD analysis (05.3-64)

Ramseier D, Connolly J, Bazzaz F A

Recent climate change: Rethinking drought in the context of Forest Fire Research in Ticino, South of

Switzerland (05.3-65)

Reinhard M, Rebetez M, Schlaepfer R

CO2 emissions from red wood ant (Formica rufa group) mounds: Seasonal and diurnal patterns related to air

temperature (05.3-66)

Risch A C, Schutz M, Jurgensen M F, Domisch T, Ohashi M, Finer L

Effect of land management on ecosystem carbon fluxes at a subalpine grassland site in the Swiss Alps (05.3-67)

Rogiers N, Eugster W, Furger M, Siegwolf R

Habitat and plant specificity of Trichogramma egg parasitoids - underlying mechanisms and implications

(05.3-68)

Romeis A, Babendreier D, Wackers F L, Shanower T G

Reducing vulnerability of agriculture and forestry to climate variability and change: Workshop summary and

recommendations (05.3-69)

Salinger M J, Sivakumar M V K, Motha R

Impacts of present and future climate variability and change on agriculture and forestry in the arid and semiarid

tropics (05.3-70)

Sivakumar M V K, Das H P, Brunini O

Safe sites for tree regeneration in wooded pastures: A case of associational resistance (05.3-71)

Smit C, Beguin D, Buttler A, Müller Schärer H

The impact of windthrow on carbon sequestration in Switzerland: a model-based assessment (05.3-72)

Thurig E, Palosuo T, Bucher J, Kaufmann E

The effect of nitrogen fertilization on fungistatic phenolic compounds in roots of beech (Fagus sylvatica) and

Norway spruce (Picea abies) (05.3-73)

Tomova L, Braun S, Flückiger W

Local and landscape influence on amphibian occurrence and abundance (05.3-74)

van Buskirk J

Meta-analysis of farmland biodiversity within set-aside land: Reply to Kleijn and Baldi (05.3-75)

van Buskirk J, Willi Y

Biological flora of central Europe: Solidago gigantea Aiton (05.3-76)

Weber E, Jakobs G

Modeling the interacting effects of browsing and shading on mountain forest tree regeneration (Picea abies)

(05.3-77)

Weisberg P J, Bonavia F, Bugmann H

Global Change Abstracts – The Swiss Contribution 11


Epiphytic macrolichen communities along regional gradients in northern Norway (05.3-78)

Werth S, Tommervik H, Elvebakk A

Carbon dynamics in a temperate grassland soil after 9 years exposure to elevated CO2 (Swiss FACE) (05.3-79)

Xie Z B, Cadisch G, Edwards G, Baggs E M, Blum H

Increasing population density and seed production with altitude in Eritrichium nanum (Boraginaceae) -

An arctic alpine obligatory seeder (05.3-80)

Zoller H, Lenzin H, Rusterholz H P, Stöcklin J

No down-regulation of leaf photosynthesis in mature forest trees after three years of exposure to elevated

CO2 (05.3-81)

Zotz G, Pepin S, Körner C

1.3 Soil and Litosphere 48

Variability of available cadmium in relation to soil properties and landuse in an arid region in central Iran

(05.3-82)

Amini M, Khademi H, Afyuni M, Abbaspour K C

Effects of increasing fire frequency on black carbon and organic matter in Podzols of Siberian Scots pine

forests (05.3-83)

Czimczik C I, Schmidt M W I, Schulze E D

Carbon and nitrogen isotope composition of bulk soils, particle-size fractions and organic material after

treatment with hydrofluoric acid (05.3-84)

Schmidt M W I, Gleixner G

Modelling the behaviour of a large landslide with respect to hydrogeological and geomechanical parameter

heterogeneity (05.3-85)

Tacher L, Bonnard C, Laloui L, Parriaux A

Simultaneous estimation of diffusive volatile organic compound (VOC) fluxes and non-aqueous phase liquid

(NAPL) saturation in the vadose zone (05.3-86)

Werner D, Broholm M, Höhener P

1.4 Cryosphere 50

Triaxial constant stress and constant strain rate tests on ice-rich permafrost samples (05.3-87)

Arenson L, Springman S

Mathematical descriptions for the behaviour of ice-rich frozen soils at temperatures close to 0 C (05.3-88)

Arenson L, Springman S

The influence of seasonally frozen soil on the snowmelt runoff at two Alpine sites in southern Switzerland

(05.3-89)

Bayard D, Stähli M, Parriaux A, Flühler H

Isotopic view on nitrate loss in Antarctic surface snow (05.3-90)

Blunier T, Floch G L, Jacobi H W, Quansah E

Validation of the energy budget of an alpine snowpack simulated by several snow models (SnowMIP project)

(05.3-91)

Etchevers P, Martin E, Brown R, Fierz C, Lejeune Y, Bazile E, Boone A, Dai Y, Essery R, Fernandez A,

Gusev Y, Jordan R, Koren V, Kowalcyzk E, Nasonova N O, Pyles R D, Schlosser A, Shmakin A B,

Smirnova T G, Strasser U, Verseghy D, Yamazaki T, Yang Z L

Operational sub-pixel snow mapping over the Alps with NOAA AVHRR data (05.3-92)

Foppa N, Wunderle S, Hauser A, Oesch D, Kuchen F

SNOWPACK model simulations for snow in Hokkaido, Japan (05.3-93)

Hirashima H, Nishimura K, Baba E, Hachikubo A, Lehning M

Reconciling different observational data sets from Surface Heat Budget of the Arctic Ocean (SHEBA) for

model validation purposes (05.3-94)

Huwald H, Tremblay L B, Blatter H

12

SHORT LIST OF ALL ABSTRACTS

Global Change Abstracts – The Swiss Contribution


SHORT LIST OF ALL ABSTRACTS

A multilayer sigma-coordinate thermodynamic sea ice model: Validation against Surface Heat Budget of the

Arctic Ocean (SHEBA)/Sea Ice Model Intercomparison Project Part 2 (SIMIP2) data (05.3-95)

Huwald H, Tremblay L B, Blatter H

Advance mechanisms of rock glaciers (05.3-96)

Kaab A, Reichmuth T

Impact of artificial snow and ski-slope grooming on snowpack properties and soil thermal regime in a

sub-alpine ski area (05.3-97)

Keller T, Pielmeier C, Rixen C, Gadient F, Gustafsson D, Stahli M

Estimating snow conditions in Finland in the late 21st century using the SNOWPACK model with regional

climate scenario data as input (05.3-98)

Rasmus S, Raisanen J, Lehning M

A new in situ sensor for large-scale snow-cover monitoring (05.3-99)

Stähli M, Stacheder M, Gustafsson D, Schlaeger S, Schneebel M, Brandelik A

Pol-InSAR observations from an Alpine glacier in the cold infiltration zone at L- and P-band (05.3-100)

Stebler O, Schwerzmann A, Lüthi M, Meier E, Nuesch D

Application of the numerical snowpack model (SNOWPACK) to the wet- snow region in Japan (05.3-101)

Yamaguchi S, Sato A, Lehning M

1.5 Oceans and Fresh Water Systems 55

Stereoisomer composition of the chiral UV filter 4-methylbenzylidene camphor in environmental samples

(05.3-102)

Buser H R, Müller M D, Balmer M E, Poiger T, Buerge I J

Special section - Mountain waters: climatic and hydrological sensitivity (05.3-103)

Corripio J G, de Jong C

In vitro assessment of modes of toxic action of pharmaceuticals in aquatic life (05.3-104)

Escher B I, Bramaz N, Eggen R I L, Richter M

An environmentally relevant concentration of estrogen induces arrest of male gonad development in

zebrafish, Danio rerio (05.3-105)

Fenske M, Maack G, Schafers C, Segner H

Depositional history of organic contaminants in Narragansett Bay, Rhode Island, USA (05.3-106)

Hartmann P C, Quinn J G, Cairns R W, King J W

Climatic change and the effect on hydrology and water management in the Rhine basin (05.3-107)

Krahe P, Buiteveld H, Pfister L, Ritz C, Sprokkereef E

Stochastic modeling of diffuse pesticide losses from a small agricultural catchment (05.3-108)

Lindahl A M L, Kreuger J, Stenstrom J, Gardenas A I, Alavi G, Roulier S, Jarvis N J

Altitude-dependent differences in the primary physical response of mountain lakes to climatic forcing (05.3-109)

Livinstone D M, Lotter A F, Kettle H

Ocean gyres and abrupt change in the thermohaline circulation: A conceptual analysis (05.3-110)

Longworth H, Marotzke J, Stocker T F

Use of slow filtration columns to assess oxygen respiration, consumption of dissolved organic carbon, nitrogen

transformations. and microbial parameters in hyporheic sediments (05.3-111)

Mermillod Blondin F, Mauclaire L, Montuelle B

Comet assay with the fish cell line rainbow trout gonad-2 for in vitro genotoxicity testing of xenobiotics and

surface waters (05.3-112)

Nehls S, Segner H

A Bayesian combination method of flood models: Principles and application results (05.3-113)

Niggli M, Musy A

Effectsd of riparian arthropod predation on the biomass and abundance of aquatic insect emergence (05.3-114)

Paetzold A, Tockner K

Global Change Abstracts – The Swiss Contribution 13


Effects of 12 years' operation of a sewage treatment plant on trace metal occurrence within a Mediterranean

commercial sponge (Spongia officinalis, Demospongiae) (05.3-115)

Perez T, Longet D, Schembri T, Rebouillon P, Vacelet J

Phosphorus retention in small constructed wetlands treating agricultural drainage water (05.3-116)

Reinhardt M, Gachter R, Wehrli B, Müller B

Simple determination of the herbicide napropamide in water and soil samples by room temperature

phosphorescence (05.3-117)

Salinas Castillo A, Fernandez Sanchez J F, Segura Carretero A, Fernandez Gutierrez A

Weak mixing in Lake Kivu: New insights indicate increasing risk of uncontrolled gas eruption (05.3-118)

Schmid M, Halbwachs M, Wehrli B, Wüest A

Factors controlling delta C-13 values of sedimentary carbon in hypertrophic Baldeggersee, Switzerland, and

implications for interpreting isotope excursions in lake sedimentary records (05.3-119)

Teranes J L, Bernasconi S M

Planform channel dynamics of the lower Colorado River: 1976-2000 (05.3-120)

Tiegs S D, Pohl M

The hydrological significance of mountains: from regional to global scale (05.3-121)

Viviroli D, Weingartner R

Removal of heavy metals from mine waters by natural zeolites (05.3-122)

Wingenfelder U, Hansen C, Furrer G, Schulin R

Carbon isotope fractionation in the reductive dehalogenation of carbon tetrachloride at iron (hydr)oxide and

iron sulfide minerals (05.3-123)

Zwank L, Elsner M, Aeberhard A, Schwarzenbach R P, Haderlein S B

1.6 Energy Balance 63

Comparison of modeled and observed cloud-free longwave downward radiation over the Alps (05.3-124)

Durr B, Philipona R, Schubiger F, Ohmura A

On the determination of surface emissivity from satellite observations (05.3-125)

Mätzler C

Measurements and model calculations of the solar shortwave fluxes in snow on Summit, Greenland (05.3-126)

Meirold Mautner I, Lehning M

Climate - How unusual is today's solar activity (05.3-127)

Müscheler R, Joos F, Müller S A, Snowball I

Cloud effects on the radiation budget based on ISCCP data (1991 to 1995) (05.3-128)

Raschke E, Ohmura A, Rossow W B, Carlson B E, Zhang Y C, Stubenrauch C, Kottek M, Wild M

Climate - How unusual is today's solar activity? Reply (05.3-129)

Solanki S K, Usoskin I G, Kromer B, Schüssler M, Beer J

From dimming to brightening: Decadal changes in solar radiation at Earth's surface (05.3-130)

Wild M, Gilgen H, Roesch A, Ohmura A, Long C N, Dutton E G, Forgan B, Kallis A, Russak V, Tsvetkov A

1.7 Coupled Systems and Cycles 65

Comparing CO2 storage and advection conditions at night at different carboeuroflux sites (05.3-131)

Aubinet M, Berbigier P, Bernhofer C H, Cescatti A, Feigenwinter C, Granier A, Grunwald T H, Havrankova K,

Heinesch B, Longdoz B, Marcolla B, Montagnani L, Sedlak P

Plant, soil microbial and soil inorganic nitrogen responses to elevated CO2: a study in microcosms of Holcus

lanatus (05.3-132)

Barnard R, Leadley P W, Lensi R, Barthes L

Ratio of the Greenland to global temperature change: Comparison of observations and climate modeling

results (05.3-133)

Chylek P, Lohmann U

14

Global Change Abstracts – The Swiss Contribution

SHORT LIST OF ALL ABSTRACTS


SHORT LIST OF ALL ABSTRACTS

Comparing estimates of persistence and long-range transport potential among multimedia models (05.3-134)

Fenner K, Scheringer M, Macleod M, Matthies M, Mckone T, Stroebe M, Beyer A, Bonnell M, Le Gall A C,

Klasmeier J, Mackay D, van de Meent D, Pennington D, Scharenberg B, Suzuki N, Wania F

The role of vegetation and litter in the nitrogen dynamics of riparian buffer zones in Europe (05.3-135)

Hefting M M, Clement J C, Bienkowski P, Dowrick D, Guenat C, Butturini A, Topa S, Pinay G, Verhoeven J T A

Pan-European delta C-13 values of air and organic matter from forest ecosystems (05.3-136)

Hemming D, Yakir D, Ambus P, Aurela M, Besson C, Black K, Buchmann N, Burlett R, Cescatti A, Clement R,

Gross P, Granier A, Grünwald T H, Havrankova K, Janous D, Janssens I A, Knohl A, Ostner B K, Kowalski A,

Laurila T, Mata C, Marcolla B, Matteucci G, Moncrieff J, Moors E J, Osborne B, Pereira J S, Pihlatie M,

Pilegaard K, Ponti F, Rosova Z, Rossi F, Scartazza A, Vesala T

Inorganic nitrogen storage in alpine snow pack in the Central Alps (Switzerland) (05.3-137)

Hiltbrunner E, Schwikowski M, Körner C

Water regime of metal-contaminated soil under juvenile forest vegetation (05.3-138)

Menon M, Hermle S, Abbaspour K C, Günthardt Georg M S, Oswald S E, Schulin R

Modeling diurnal to seasonal water and heat exchanges at European Fluxnet sites (05.3-139)

Stöckli R, Vidale P L

Atmospheric deposition on swiss long-term forest ecosystem research (LWF) plots (05.3-140)

Thimonier A, Schmitt M, Waldner P, Rihm B

Prognostic canopy air space solutions for land surface exchanges (05.3-141)

Vidale P L, Stöckli R

2 Past Global Changes 69

Late Maastrichtian and K/T paleoenvironment of the eastern Tethys (Israel): mineralogy, trace and platinum

group elements, biostratigraphy and faunal turnovers (05.3-142)

Adatte T, Keller G, Stuben D, Harting M, Kramar U, Stinnesbeck W, Abramovich S, Benjamini C M

Palaeoclimatology - Formation of Precambrian sediment ripples - Reply (05.3-143)

Allen P, Hoffman P

Differential dissolution of Lake Baikal diatoms: correction factors and implications for palaeoclimatic

reconstruction (05.3-144)

Battarbee R W, Mackay A W, Jewson D H, Ryves D B, Sturm M

Release of gas bubbles from lake sediment traced by noble gas isotopes in the sediment pore water (05.3-145)

Brennwald M S, Kipfer R, Imboden D M

8,000 years of human warmth (05.3-146)

Broecker W S, Stocker T F

Combined winter climate regimes over the North Atlantic/European sector 1766-2000 (05.3-147)

Casty C, Handorf D, Sempf M

Paleoclimatic control of biogeographic and sedimentary events in Tethyan and peri-Tethyan areas during the

Oxfordian (Late Jurassic) (05.3-148)

Cecca F, Garin B M, Marchand D, Lathuiliere B, Bartolini A

Modem pollen-vegetation relationships in the Champsaur valley (French Alps) and their potential in the

interpretation of fossil pollen records of past cultural landscapes (05.3-149)

Court Picon M, Buttler A, de Beaulieu J L

Flux of lipophilic photosynthetic pigments to the surface sediments of Lake Baikal (05.3-150)

Fietz S, Sturm M, Nicklisch A

A glacial stage spanning the Antarctic Cold Reversal in Torres del Paine (51 degrees S), Chile, based on

preliminary cosmogenic exposure ages (05.3-151)

Fogwill C J, Kubik P W

Phosphogenesis and organic-carbon preservation in the miocene monterey formation at Naples beach,

California - The monterey hypothesis revisited (05.3-152)

Föllmi K B, Badertscher C, de Kaenel E, Stille P, John C M, Adatte T, Steinmann P

Global Change Abstracts – The Swiss Contribution 15


Relative age dating of Alpine rockglacier surfaces (05.3-153)

Frauenfelder R, Laustela M, Kaab A

Early-Holocene afforestation processes in the lower subalpine belt of the Central Swiss Alps as inferred from

macrofossil and pollen records (05.3-154)

Gobet E, Tinner W, Bigler C, Hochuli P A, Ammann B

Calcium isotope (delta Ca-44/40) variations of Neogene planktonic foraminifera (05.3-155)

Heuser A, Eisenhauer A, Bohm F, Wallmann K, Gussone N, Pearson P N, Nagler T F, Dullo W C

Glacial/interglacial changes in subarctic North Pacific stratification (05.3-156)

Jaccard S L, Haug G H, Sigman D M, Pedersen T F, Thierstein H R, Rohl U

Modeling tree species migration in the Alps during the Holocene: What creates complexity? (05.3-157)

Lischke H

1000 years of climate variability in central Asia: assessing the evidence using Lake Baikal (Russia) diatom

assemblages and the application of a diatom-inferred model of snow cover on the lake (05.3-158)

Mackay A W, Ryves D B, Battarbee R W, Flower R J, Jewson D H, Rioual P, Sturm M

GRIP deuterium excess reveals rapid and orbital-scale changes in Greenland moisture origin (05.3-159)

Masson Delmotte V, Jouzel J, Landais A, Stievenard M, Johnsen S J, White J W C, Werner M,

Sveinbjornsdottir A, Fuhrer K

Chronology of the last glaciation in central Strait of Magellan and Bahia Inutil, southernmost South America

(05.3-160)

Mcculloch R D, Fogwill C J, Sugden D E, Bentley M J, Kubik P W

Internal carbon and nutrient cycling in Lake Baikal: sedimentation, upwelling, and early diagenesis (05.3-161)

Müller B, Maerki M, Schmid M, Vologina E G, Wehrli B, Wüest A, Sturm M

Effects of sample mass and macrofossil type on radiocarbon dating of arctic and boreal lake sediments (05.3-162)

Oswald W W, Anderson P M, Brown T A, Brubaker L B, Hu F S, Lozhkin A V, Tinner W, Kaltenrieder P

Late quaternary history of the coastal Wahiba Sands, Sultanate of Oman (05.3-163)

Preusser F, Radies D, Driehorst F, Matter A

Paleoclimatic significance of Early Holocene faunal assemblages in wet interdune deposits of the Wahiba

Sand Sea, sultanate of Oman (05.3-164)

Radies D, Hasiots S T, Preusser F, Neubert E, Matter A

The last glacial/interglacial cycle at two sites in the Chinese Loess Plateau: Mineral magnetic, grain-size and

Be-10 measurements and estimates of palaeoprecipitation (05.3-165)

Sartori M, Evans M E, Heller F, Tsatskin A, Han J M

A record of the Jurassic/Cretaceous boundary climatic variation on the southern margin of the Tethys : clay

minerals and palynofacies of the early Cretaceous Jebel Meloussi section (Central Tunisia, Sidi Kralif

Formation) (05.3-166)

Schnyder J, Gorin G, Soussi M, Baudin F, Deconinck J F

Analyzing rockfall activity (1600-2002) in a protection forest - a case study using dendrogeomorphology (05.3-167)

Stoffel M, Schneuwly D, Bollschweiler M, Lievre I, Delaloye R, Myint M, Monbaron M

Late-glacial glacier events in southernmost South America: A blend of 'northern'and 'southern' hemispheric

climatic signals? (05.3-168)

Sugden D E, Bentley M J, Fogwill C J, Hulton N R J, Mcculloch R D, Purves R S

Solving the paradox of the end of the Little Ice Age in the Alps (05.3-169)

Vincent C, Le Meur E, Six D, Funk M

A 500 year dendroclimatic reconstruction of spring-summer precipitation from the lower Bavarian Forest

region, Germany (05.3-170)

Wilson R J S, Luckman B H, Esper J

3 Human Dimensions 80

Jevons' paradox (05.3-171)

Alcott B

Human health, well-being, and global ecological scenarios (05.3-172)

Butler C D, Corvalan C F, Koren H S

16

Global Change Abstracts – The Swiss Contribution

SHORT LIST OF ALL ABSTRACTS


SHORT LIST OF ALL ABSTRACTS

The global burden of disease due to outdoor air pollution (05.3-173)

Cohen A J, Anderson H R, Ostro B, Pandey K D, Krzyzanowski M, Künzli N, Gutschmidt K, Pope A, Romieu I,

Samet J M, Smith K

Personal exposures to VOC in the upper end of the distribution - relationships to indoor, outdoor and workplace

concentrations (05.3-174)

Edwards R D, Schweizer C, Jantunen M, Lai H K, Bayer Oglesby L, Katsouyanni K, Nieuwenhuijsen M,

Saarela K, Sram R, Künzli N

Prioritizing long-term watershed management strategies using group decision analysis (05.3-175)

Ghanbarpour M R, Hipel K W, Abbaspour K C

Risk perception of heavy metal soil contamination by high-exposed and low-exposed inhabitants: The role of

knowledge and emotional concerns (05.3-176)

Grasmuck D, Scholz R W

Heat wave 2003 and mortality in Switzerland (05.3-177)

Grize L, Huss A, Thommen O, Schindler C, Braun Fahrländer C

Agri-environment schemes as landscape experiments - Preface (05.3-178)

Herzog F

Reconsidering the risk assessment concept: Standardizing the impact description as a building block for

vulnerability assessment (05.3-179)

Hollenstein K

A call for reporting the relevant exposure term in air pollution case-crossover studies (05.3-180)

Künzli N, Schindler C

Energy in the perspective of the sustainable development: The 2000 W society challenge (05.3-181)

Marechal F, Favrat D, Jochem E

Statistical analysis of CDM capacity-building needs (05.3-182)

Nondek L, Arquit Niederberger A

Policy principles and implementation guidelines for private sector participation in the water sector -

a step towards better results (05.3-183)

Rothenberger D, Frei U, Brugger F

Distribution of energy consumption and the 2000 W/capita target (05.3-184)

Spreng D

Between conservation and development - Concretizing the first World Natural Heritage Site in the Alps

through participatory processes (05.3-185)

Wiesman U, Liechti K, Rist S

Towards sustainable land use: identifying and managing the conflicts between human activities and

biodiversity conservation in Europe (05.3-186)

Young J, Watt A, Nowicki P, Alard D, Clitherow J, Henle K, Johnson R, Laczko E, Mccracken D, Matouch S,

Niemela J, Richards C

4 Mitigation and Adaptation Technologies 85

Towards accurate instantaneous emission models (05.3-187)

Ajtay D, Weilenmann M, Soltic P

Physical characterization of particulate emissions from diesel engines: a review (05.3-188)

Burtscher H

The air membrane-ATR integrated gas turbine power cycle: A method for producing electricity with low CO2

emissions (05.3-189)

Fiaschi D, Gamberi F, Bartlett M, Griffin T

Greenhouse gas emission reduction options: modeling and implications (05.3-190)

Hirschberg S

FULLSPECTRUM: a new PV wave making more efficient use of the solar spectrum (05.3-191)

Luque A, Marti A, Bett A, Andreev V M, Jaussaud C, van Roosmalen J A M, Alonso J, Rauber A, Strobl G,

Stolz W, Algora C, Bitnar B, Gombert A, Stanley C, Wahnon P, Conesa J C, van Sark W G J H M, Meijerink A,

van Klink G P M, Barnham K, Danz R, Meyer T, Luque Heredia I, Kenny R, Christofides C, Sala G, Benitez P

Global Change Abstracts – The Swiss Contribution 17


Sustainability-guided promotion of renewable electricity generation (05.3-192)

Madlener R, Stagl S

Comparison of mass-based and non-mass-based particle measurement systems for ultra-low emissions from

automotive sources (05.3-193)

Mohr M, Lehmann U, Rutter J

Regulated and nonregulated diesel and gasoline cold start emissions at different temperatures (05.3-194)

Weilenmann M, Soltic P, Saxer C, Forss A M, Heeb N

5 General Topics 88

Mountain climates and climatic change: An overview of processes focusing on the European Alps (05.3-195)

Beniston M

Knowledge for sustainable development in the Tajik Pamir Mountains (05.3-196)

Breu T, Maselli D, Hurni H

Life-cycle inventory of waste solvent distillation: Statistical analysis of empirical data (05.3-197)

Capello C, Hellweg S, Badertscher B, Hungerbühler K

Life-cycle assessment in pesticide product development: Methods and case study on two plant-growth regulators

from different product generations (05.3-198)

Geisler G, Hellweg S, Hofstetter T B, Hungerbühler K

Uncertainty analysis in life cycle assessment (LCA): Case study on plant-protection products and implications

for decision making (05.3-199)

Geisler G, Hellweg S, Hungerbühler K

The implications of changes in population, land use, and land management for surface runoff in the upper

Nile Basin area of Ethiopia (05.3-200)

Hurni H, Tato K, Zeleke G

Life cycle assessment of crystalline photovoltaics in the swiss ecoinvent database (05.3-201)

Jungbluth N

'The ecology of scale: Assessment of regional energy turnover and comparison with global food' by Elmar

Schlich and Ulla Fleissner (05.3-202)

Jungbluth N, Demmeler M

Scientists need back-up by climate organizations (05.3-203)

Körner C, Wanner H, Ritz C

Mapping disastrous natural hazards using global datasets (05.3-204)

Peduzzi P, Dao H, Herold C

Solution spaces for decision-making - a sustainability assessment tool for city-regions (05.3-205)

Wiek A, Binder C

18

Global Change Abstracts – The Swiss Contribution

SHORT LIST OF ALL ABSTRACTS


1 Earth System Process Studies and Methodologies

05.3-1

Long-range transport to Europe: Seasonal

variations and implications for the European

ozone budget

Auvray M, Bey I

Switzerland

Meteorology & Atmospheric Sciences , Modelling

We use a chemical transport model (GEOS-CHEM) to

quantify the contribution of long-range transported

pollution to the European ozone (O-3) budget for the

year 1997. The model reproduces the main features

observed over Europe for O-3, carbon monoxide and

nitrogen dioxides, as well as two events of enhanced

O-3 of North American origin over the eastern North

Atlantic and over Europe. North American O-3 fluxes

into Europe experience a maximum in spring and

summer, reflecting the seasonal variation in photochemical

activity and in export pathways. In summer,

North American O-3 enters Europe at higher altitudes

and lower latitudes because of deep convection, and

because the flow over the North Atlantic is mostly

zonal in that season. The low-level inflow is only important

in spring, when loss rates in the boundary layer

over the North Atlantic are weaker. Asian O-3 arrives

mainly via the westerlies, and usually at higher

altitudes than North American O-3 because of

stronger deep convection over Asia. In addition, Asian

O-3 fluxes are at a maximum in summer during the

monsoon period because of enhanced convection

over Asia, increased nitrogen oxides sources from

lightning and direct transport towards Europe via the

monsoon easterlies. Over Europe, total background

accounts for 30 ppbv at the surface. North American

and Asian O-3 contribute substantially to the annual

O-3 budget over Europe, accounting for 10.9% and

7.7%, respectively, while the European contribution

only accounts for 9.4%. We find that in summer, at the

surface, O-3 decreases over Europe from 1980 to

1997, reflecting the reduction of European O-3 precursor

emissions. In the free troposphere, this decrease

is compensated by the increase in O-3 due to

increasing Asian emissions. This may explain the lack

of trends observed over most of the European region,

especially at mountain sites.

Journal of Geophysical Research Atmospheres, 2005,

V110, ND11, JUN 2, ARTN: D11303

1.1 Atmosphere

05.3-2

Trace metals in ambient air: Hourly size-segregated

mass concentrations determined by

Synchrotron-XRF

Bukowiecki N, Hill M, Gehrig R, Zwicky C N,

Lienemann P, Hegedus F, Falkenberg G,

Weingartner E, Baltensperger U

Switzerland, Germany

Engineering , Meteorology & Atmospheric Sciences

Trace metals are ubiquitous in urban ambient air, with

mass concentrations in the range of a few µg/m(3)

down to less than 100 pg/m(3). To measure such low

concentrations represents a challenge for chemical

and physical analysis. In this study, ambient aerosol

was collected in Zurich (Switzerland) in 1-h intervals

and three size fractions (aerodynamic diameters 0.1-1

µm, 1-2.5 µm, and 2.5-10 µm), using a three-stage rotating

drum impactor (RDI). The samples were analyzed

by energy-dispersive Synchrotron radiation Xray

fluorescence spectrometry (SR-XRF) to obtain

size-segregated hourly elemental aerosol mass concentrations

for Cr, Mn, Fe, Cu, Zn, Br, and Pb, along

with S, Cl, and Ca under the selected experimental

conditions. The high sensitivity of SR-XRF allowed for

detection limits of < 50 pg/m(3) for most of the above

elements, with a net analysis time of only 15 s per

sample. The data obtained with this technique illustrate

that there is a considerable gain of relevant information

when time resolution for measurements is increased

from 1 day to 1 h. The individual size fractions

of a specific element may show significantly different

short-term patterns.

Environmental Science Technology, 2005, V39, N15,

AUG 1, pp 5754-5762

05.3-3

The influence of south foehn on the ozone mixing

ratios at the high alpine site Arosa

Campana M, Li Y S, Staehelin J, Prevot A S H,

Bonasoni P, Loetscher H, Peter T

Switzerland, Italy

Meteorology & Atmospheric Sciences

Within 2 years of trace gas measurements performed

at Arosa (Switzerland, 2030m above sea level), enhanced

ozone mixing ratios were observed during

south foehn events during summer and spring (5-10

ppb above the median value). The enhancements can

Global Change Abstracts – The Swiss Contribution 19


e traced back to ozone produced in the strongly industrialized

Po basin as confirmed by various analyses.

Backward trajectories clearly show advection

from this region during foehn. NOy versus O-3 correlation

and comparison of 03 mixing ratios between

Arosa and Mt. Cimone (Italy, 2165 m asl) suggest that

ozone is the result of recent photochemical production

( + 5.6 ppb on average), either directly formed during

the transport or via mixing of air processed in the Po

basin boundary layer. The absence of a correlation

between air parcel residence times over Europe and

ozone mixing ratios at Arosa during foehn events is in

contrast to a previous analysis, which suggested such

correlation without reference to the origin of the air. In

the case of south foehn, the continental scale influence

of pollutants emission on ozone at Arosa appears

to be far less important than the direct influence

of the Po basin emissions. In contrast, winter time displays

a different situation, with mean ozone reductions

of about 4ppb for air parcels passing the Po

basin, probably caused by mixing with ozone-poor air

from the Po basin boundary layer.

Atmospheric Environment, 2005, V39, N16, MAY,

pp 2945-2955

05.3-4

Statistical analysis of the vehicle pollutant

emissions derived from several European road

tunnel studies

Colberg C A, Tona B, Catone G, Sangiorgio C,

Stahel W A, Sturm P, Staehelin J

Switzerland, Austria

Meteorology & Atmospheric Sciences , Energy &

Fuels

Real-world emission rates of road traffic Can be quantified

by measurements in road tunnels. Emission factors

(EFs) of in-use vehicles can be determined and

the impact of major changes in technology and fuel

composition can be estimated. Here, we present tunnel

measurements of nitrogen oxides (NO,), carbon

monoxide (CO), and total volatile organic compounds

(t-VOCs) performed in spring 2001 in the Lundby tunnel

(Sweden), in fall 2001 in the Plabutsch tunnel

(Austria) and in fall 2002 in the Gubrist tunnel

(Switzerland) . In this paper, we derive EFs for light

and heavy duty vehicles (LDVs and HDVs) by the statistical

method of linear and non-linear regression

analysis. The results demonstrate the large effect of

the tunnel road gradient for NO, emissions of HDVs,

whereas the influence of the road gradient is less pronounced

for LDV emissions of NO, and CO. The developed

statistical modeling approach allows the determination

of EFs as a function of vehicle speed. The

results also indicate a dependence of the EFs on the

day of the week, probably caused by differences in

the fleet composition.

Atmospheric Environment, 2005, V39, N13, APR,

pp 2499-2511

20

1.1 ATMOSPHERE

Global Change Abstracts – The Swiss Contribution

05.3-5

Black carbon ageing in the Canadian Centre for

Climate modelling and analysis atmospheric

general circulation model

Croft B, Lohmann U, von Salzen K

Canada, Switzerland

Geochemistry & Geophysics , Modelling ,

Meteorology & Atmospheric Sciences

Black carbon ( BC) particles in the atmosphere have

important impacts on climate. The amount of BC in

the atmosphere must be carefully quantified to allow

evaluation of the climate effects of this type of

aerosol. In this study, we present the treatment of BC

aerosol in the developmental version of the 4th generation

Canadian Centre for Climate modelling and

analysis (CCCma) atmospheric general circulation

model (AGCM). The focus of this work is on the conversion

of insoluble BC to soluble/mixed BC by physical

and chemical ageing. Physical processes include

the condensation of sulphuric and nitric acid onto the

BC aerosol, and coagulation with more soluble

aerosols such as sulphates and nitrates. Chemical

processes that may age the BC aerosol include the

oxidation of organic coatings by ozone. Four separate

parameterizations of the ageing process are compared

to a control simulation that assumes no ageing

occurs. These simulations use 1) an exponential decay

with a fixed 24 h half-life, 2) a condensation and

coagulation scheme, 3) an oxidative scheme, and 4) a

linear combination of the latter two ageing treatments.

Global BC burdens are 2.15, 0.15, 0.11, 0.21, and

0.11 Tg C for the control run, and four ageing

schemes, respectively. The BC lifetimes are 98.1, 6.6,

5.0, 9.5, and 4.9 days, respectively. The sensitivity of

modelled BC burdens, and concentrations to the factor

of two uncertainty in the emissions inventory is

shown to be greater than the sensitivity to the parameterization

used to represent the BC ageing, except

for the oxidation based parameterization. A computationally

efficient parameterization that represents the

processes of condensation, coagulation, and oxidation

is shown to simulate BC ageing well in the CCCma

AGCM. As opposed to the globally fixed ageing

time scale, this treatment of BC ageing is responsive

to varying atmospheric composition.

Atmospheric Chemistry and Physics, 2005, V5,

JUL 28, pp 1931-1949

05.3-6

Two independent methods for mapping bulk

deposition in France

Croise L, Ulrich E, Duplat P, Jaquet O

France, Switzerland

Meteorology & Atmospheric Sciences , Mapping

Two independent methods-deterministic and geostatistical-were

used to estimate the spatial distribution of

bulk deposition for nine ions and the associated un-


certainties for France. The deterministic models enable

bulk deposition estimates using only a few auxiliary

variables (precipitation, altitude and the period in

the year). The models explain between 38% and 64%

of the depositional variability depending on the The

compounds can be grouped according to their primary

origin: (1) (S-SO42-, N-NO3-, N-NH4+, N-tot, H+) with

high deposition levels in the case of heavy precipitation,

and (2) (Na+, Cl-, Mg2+) with high deposition

levels near the sea. Model validation for 1999, 2000

and 2001 generally shows a close relationship between

calculated and measured bulk deposition. However,

the models overestimate the values for smaller

deposition quantities (S-SO42-, H+). Comparison with

EMEP (European Monitoring and Evaluation Program)

maps shows good correlation for averages at

the country level, despite spatial differences mainly

due to very different spatial scales The geostatistical

approach gave good results in spite of the small number

(27) of plots in the CATAENAT sub-network. Spatially

structured behaviour was identified and quantified

for all the compounds. The contribution of one

auxiliary variable (precipitation at 2614 "Meteo-

France" weather stations) appears to be significant for

most of the interpolations. The maps produced were

globally similar to those obtained with the deterministic

approach. However, the deterministic approach

slightly overestimated (7-11%) or underestimated (17-

24%) bulk deposition depending on the ion. Finally,

spatial characterisation of errors and a greater potential

make the geostatistical approach more attractive

than the deterministic method for monitoring levels

above critical loads for acidity. The maps produced

were compared with EMEP maps for Europe and critical

loads are discussed.

Atmospheric Environment, 2005, V39, N21, JUL,

pp 3923-3941

05.3-7

The performance of RAMS in representing the

convective boundary layer structure in a very

steep valley

de Wekker S F J, Steyn D G, Fast J D, Rotach M W,

Zhong S

Canada, Switzerland, USA

Meteorology & Atmospheric Sciences , Hydrology ,

Modelling , Geomorphology

Data from a comprehensive field study in the Riviera

Valley of Southern Switzerland are used to investigate

convective boundary layer structure in a steep valley

and to evaluate wind and temperature fields, convective

boundary layer height, and surface sensible heat

fluxes as predicted by the mesoscale model RAMS.

Current parameterizations of surface and boundary

layer processes in RAMS, as well as in other

mesoscale models, are based on scaling laws strictly

valid only for flat topography and uniform land cover.

Model evaluation is required to investigate whether

1.1 ATMOSPHERE

this limits the applicability of RAMS in steep, inhomogeneous

terrain. One clear-sky day with light synoptic

winds is selected from the field study. Observed temperature

structure across and along the valley is nearly

homogeneous while wind structure is complex with

a wind speed maximum on one side of the valley. Upvalley

flows are not purely thermally driven and mechanical

effects near the valley entrance also affect

the wind structure. RAMS captured many of the observed

boundary layer characteristics within the steep

valley. The wind field, temperature structure, and convective

boundary layer height in the valley are qualitatively

simulated by RAMS, but the horizontal temperature

structure across and along the valley is less homogeneous

in the model than in the observations.

The model reproduced the observed net radiation, except

around sunset and sunrise when RAMS does not

take into account the shadows cast by the surrounding

topography. The observed sensible heat fluxes fall

within the range of simulated values at grid points surrounding

the measurement sites. Some of the scatter

between observed and simulated turbulent sensible

heat fluxes are due to sub-grid scale effects related to

local topography.

Environmental Fluid Mechanics, 2005, V5, N1-2,

APR, pp 35-62

05.3-8

Middle Atmospheric Water Vapour Radiometer

(MIAWARA): Validation and first results of the

LAPBIAT Upper Tropospheric Lower Stratospheric

Water Vapour Validation Project (LAUTLOS-

WAVVAP) campaign

Deuber B, Ilaefele A, Feist D G, Martin L, Kämpfer N,

Nedoluha G E, Yushkov V, Khaykin S, Kivi R, Vomel H

Switzerland, USA, Russia, Finland

Meteorology & Atmospheric Sciences , Hydrology

We present a validation study for the ground-based

Middle Atmospheric Water Vapour Radiometer (MI-

AWARA) operating at 22 GHz. MIAWARA measures

the water vapor profile in the range of 20-80 km. The

validation was conducted in two phases at different

geographical locations. During the first operational period

the radiometer was operated at middle latitudes

in Bern, Switzerland, and the measured water vapor

profiles were compared with the HALOE satellite instrument.

The agreement between HALOE and MI-

AWARA was for most altitudes better than 10%. In the

second comparison phase, MIAWARA took part in the

Lapland Atmosphere-Biosphere Facility (LAPBIAT)

Upper Tropospheric Lower Stratospheric Water

Vapour Validation Project (LAUTLOS-WAVVAP) campaign

in early 2004 in the subarctic region of northern

Finland. During this campaign, different balloon sondes

probed the water vapor content in the upper troposphere

and lower stratosphere. The stratospheric

water vapor profiles of the fluorescent hygrometer

FLASH-B and the NOAA frost point hygrometer mirror

Global Change Abstracts – The Swiss Contribution 21


in the range of 20-26 km were compared with the lowermost

retrieval points of MIAWARA. The agreement

between the balloon instruments and MIAWARA was

better than 2% for a total number of 10 comparable

flights. This showed the potential of MIAWARA in water

vapor retrieval down to 20 km. In addition, the

northern Finland MIAWARA profiles were compared

with POAM III water vapor profiles. This comparison

confirmed the good agreement with the other instruments,

and the difference between MIAWARA and

POAM was generally less than 8%. Finally, the tipping

curve calibration was validated with tipping curve

measurements of the All-Sky Multi Wavelength Radiometer

(ASMUWARA) which was operated 10

months side by side with MIAWARA. The agreement

of the tropospheric opacity derived from these tipping

curves agree within 1%.

Journal of Geophysical Research Atmospheres, 2005,

V110, ND13, JUL 14, ARTN: D13306

05.3-9

The use of geographic information systems in

climatology and meteorology: COST 719

Dyras I, Dobesch H, Grueter E, Perdigao A, Tveito O E,

Thornes J E, van der Wel F, Bottai L

Poland, Austria, Switzerland, Portugal, Norway,

England, Netherlands, Italy

Meteorology & Atmospheric Sciences , Mapping

The COST Action 719 started in 2001 and presently

20 European countries are participating. The main objectives

of the Action are to establish interfaces between

GIS and meteorological data, assess the availability,

contents and accessibility of meteorological

and climatological data sets and encourage and foster

European co- operation. The tasks are carried out

within three working groups concentrated on issues

such as data access and availability, methods of spatial

interpolation and developing recommendations for

standardised GIS applications. The applications that

have been adopted mainly focus on three parameters,

i.e. precipitation, temperature and energy balance for

which three demonstration projects have been formulated.

It is expected that the Action will result in recommendations

for better and more cost-effective production

of state-of-the-art meteorological and climatological

information. Also an improvement of the co-operation

between European countries in the application

of GIS in the field of meteorology, climatology and environmental

sciences should be achieved together

with better-trained personnel within the operational

and scientific divisions of national meteorological services.

Additionally, the development of a visualisation

system for climate data sets for internet applications

is under preparation. This paper provides information

concerning the work in progress on the demonstration

projects made within COST 719.

Meteorological Applications, 2005, V12, N1, MAR,

pp 1-5

22

Global Change Abstracts – The Swiss Contribution

1.1 ATMOSPHERE

05.3-10

Chemistry-climate model SOCOL: a validation of

the present-day climatology

Egorova T, Rozanov E, Zubov V, Manzini E,

Schmutz W, Peter T

Switzerland, Russia, Italy

Meteorology & Atmospheric Sciences , Modelling

In this paper we document "SOCOL", a new chemistry-climate

model, which has been ported for regular

PCs and shows good wall-clock performance. An extensive

validation of the model results against present-day

climate data obtained from observations and

assimilation data sets shows that the model describes

the climatological state of the atmosphere for the late

1990s with reasonable accuracy. The model has a

significant temperature bias only in the upper stratosphere

and near the tropopause at high latitudes. The

latter is the result of the rather low vertical resolution

of the model near the tropopause. The former can be

attributed to a crude representation of radiation heating

in the middle atmosphere. A comparison of the

simulated and observed link between the tropical

stratospheric structure and the strength of the polar

vortex shows that in general, both observations and

simulations reveal a higher temperature and ozone

mixing ratio in the lower tropical stratosphere for the

case with stronger Polar night jet (PNJ) and slower

Brewer-Dobson circulation as predicted by theoretical

studies.

Atmospheric Chemistry and Physics, 2005, V5,

JUN 21, pp 1557-1576

05.3-11

Stratospheric water vapor predicted from the

Lagrangian temperature history of air entering the

stratosphere in the tropics

Fueglistaler S, Bonazzola M, Haynes P H, Peter T

USA, England, Switzerland

Meteorology & Atmospheric Sciences , Hydrology

We present results of Lagrangian troposphere-tostratosphere

transport (TST) in the tropics based on

trajectory calculations for the period 1979-2001. The

trajectories and corresponding temperature histories

are calculated from wind and temperature fields provided

by the reanalysis data ERA-40 of the European

Centre for Medium-Range Weather Forecasts

(ECMWF). The water vapor mixing ratio of air entering

the tropical stratosphere is calculated from the minimum

saturation mixing ratio over ice encountered by

each trajectory. We show that this Lagrangian approach,

which considers the global-scale to synopticscale

dynamics of tropical TST but neglects

mesoscale dynamics and details of cloud microphysics,

substantially improves estimates of stratospheric

humidity compared to calculations based on

Eulerian mean tropical tropopause temperatures. For


the period 1979-2001 we estimate from the Lagrangian

calculation that the mean water mixing ratio

of air entering the stratosphere is 3.5 ppmv, which is

in good agreement with measurements during the

same period, ranging from 3.3 ppmv to 4 ppmv,

whereas an estimate based on an Eulerian mean calculation

is about 6 ppmv. The amplitude of the annual

cycle in water vapor mixing ratio at a potential temperature

of 400 K in the tropics estimated from the Lagrangian

calculation is compared with measurements

of water vapor from the Halogen Occultation Experiment

(HALOE). For the period 1992-2001, when

HALOE measurements and ERA-40 data overlap, we

calculate a peak-to-peak amplitude of &SIM;

1.7 ppmv, in good agreement with &SIM; 1.6 ppmv

seen in HALOE data. On average, the Lagrangian

calculations have a moist bias of &SIM; 0.2 ppmv,

equivalent to a warm bias of the Lagrangian cold point

of about 0.5 K. We conclude that the Lagrangian calculation

based on synoptic-scale velocity and temperature

fields yields estimates for stratospheric water

vapor in good agreement with observations and that

mesoscale and cloud microphysical processes need

not be invoked, at first order, to explain annual mean

and seasonal variation of water vapor mixing ratios in

the tropical lower stratosphere.

Journal of Geophysical Research Atmospheres, 2005,

V110, ND8, APR 21, ARTN: D08107

05.3-12

A new method to link PM10 concentrations from

automatic monitors to the manual gravimetric

reference method according to EN12341

Gehrig R, Hueglin C, Schwarzenbach B, Seitz T,

Buchmann B

Switzerland

Meteorology & Atmospheric Sciences

Automatic on-line monitors for particulate matter with

an aerodynamic diameter up to 10 μ m (PM10)

(TEOM, beta attenuation) are widely used in air pollution

monitoring networks. However, the data cannot

always be considered equivalent to the manual gravimetric

reference method, which is required in Europe

as well as in US for compliance measurements. In

this paper, a new method is described to obtain reference

equivalent PM 10 data series from automatic

beta- attenuation monitors based on a limited number

of gravimetric PM 10 data. The correction procedure

was tested with long-term data series from 5 Swiss

sites with different exposure characters (urban street

canyon, motorway, suburban, rural) and was shown to

produce PMl0 data, which fulfilled all requirements of

EN12341, except at a background site with very low

PM10 concentrations. At all sites, including the background

site, the correction produced excellent agree-

1.1 ATMOSPHERE

ment of the corrected monitor data for annual means

and a satisfactory match of the number of days exceeding

the short time limit value of 50 μ g m(-3)

compared to reference equivalent PM10 data.

Atmospheric Environment, 2005, V39, N12, APR,

pp 2213-2223

05.3-13

Climate-based site selection for a very large

telescope using GIS techniques

Graham E, Sarazin M, Beniston M, Collet C,

Hayoz M, Neun M, Casals P

Switzerland, Germany

Mapping , Meteorology & Atmospheric Sciences

Meteorological Applications, 2005, V12, N1, MAR,

pp 77-81

05.3-14

NOAA AVHRR derived aerosol optical depth over

land

Hauser A, Oesch D, Foppa N, Wunderle S

Switzerland

Meteorology & Atmospheric Sciences

Aerosol optical depth was retrieved from a time series

of NOAA-16 AVHRR data from May 2001 through December

2002 for Central Europe (40.5&DEG; N-

50.0&DEG; N, 0&DEG; E-17&DEG; E). In contrast to

classical methods, no a priori knowledge of the surface

reflectance is necessary, but instead the surface

reflectance is estimated from a time series including

the previous 44 days. Additionally, the area where

aerosol optical depth can be retrieved is no longer

limited to certain land cover types. Only bright surface

targets are excluded in the retrieval. To retrieve the

aerosol optical depth, the radiative transfer code

SMAC is used. Afterwards the data are averaged

within a 25 x 25 pixel region to increase the retrieval

precision. The resulting standard deviation of the

aerosol optical depth within this region is used as a

quality control parameter and suitable for a post-processing

of the initial aerosol retrieval. This post- processing

leads to a substantial increase in the retrieval

accuracy when compared to ground-based

AERONET measurements. Over 650 co- incident

AVHRR retrievals and AERONET measurements

were compared, and a correlation coefficient of 0.70

was found. Altogether, the proposed method offers

the potential to generate an aerosol climatology

based on NOAA AVHRR data, which dates back to

the early 1980s.

Journal of Geophysical Research Atmospheres, 2005,

V110, ND8, APR 30, ARTN: D08204

Global Change Abstracts – The Swiss Contribution 23


05.3-15

Do aircraft black carbon emissions affect cirrus

clouds on the global scale?

Hendricks J, Karcher B, Lohmann U, Ponater M

Germany, Switzerland

Meteorology & Atmospheric Sciences , Modelling

( 1) Potential cirrus modifications caused by aircraftproduced

black carbon ( BC) particles via heterogeneous

ice nucleation were studied with a general circulation

model. Since the role of BC in cirrus cloud

formation is currently not well known, hypothetical

scenarios based on various assumptions on the ice

nucleation efficiency of background and aircraft-induced

BC particles were considered. Using these

scenarios, the sensitivity of ice cloud microphysics to

aviation-induced BC perturbations is studied. The

model results suggest that cloud modifications induced

by aircraft BC particles could change the ice

crystal number concentration at northern midlatitudes

significantly ( 10-40% changes of annual mean zonal

averages at main flight altitudes), provided that such

BC particles serve as efficient ice nuclei. The sign of

the effect depends on the specific assumptions on

aerosol-induced ice nucleation. These results demonstrate

that, based on the current knowledge, significant

cirrus modifications by BC from aircraft cannot

be excluded.

Geophysical Research Letters, 2005, V32, N12,

JUN 24 ARTN: L12814

05.3-16

Climatology of mountain venting-induced

elevated moisture layers in the lee of the Alps

Henne S, Furger M, Prevot A S H

Switzerland

Hydrology , Meteorology & Atmospheric Sciences

Elevated moisture layers in the lower free troposphere

(2000-6000 m MSL) in the lee of the Alps were investigated.

Specific humidity was analyzed within a Lagrangian

concept for fair-weather days during a 12-yr

period at the windward and the leeward sides of the

Alps for the sounding sites of Payerne, Switzerland,

and Milan, Italy. During daytime fair-weather conditions

(different criteria), specific humidity increased

significantly in air masses that advected from Payerne

to Milan in a layer ranging from similar to 2500 to

4000 m MSL. The maximum relative increase of specific

humidity in this layer was similar to 0.3, meaning

that similar to 30% of the air in this layer originated

from the Alpine atmospheric boundary layer. On average,

similar to 30% of the mass of the Alpine boundary

layer was vented to altitudes higher than 2500 m

MSL per hour during the daytime. The total precipitable

water within a layer reaching from 2500 to 3500

m MSL increased by similar to 1.3 mm. Similar elevated

layers were observed for different selection methods

of fair-weather days, and climatologically for the

24

1.1 ATMOSPHERE

Global Change Abstracts – The Swiss Contribution

whole of June, July, and August. Average observations

of the relative increase and boundary layer export

rate agree with results from the local case studies.

Daytime thermally driven flow systems seem to

be the main source of additional water vapor in the

observed elevated layers over the Alps. Subsequently,

horizontal advection toward flat terrain where the

average ABL top was well below the elevated layer

bottom results in the export of ABL air to the free troposphere

(mountain venting). Mountain venting was

enhanced in situations with larger global radiation,

lower atmospheric stability, and additional moist convection

as was detected by lightning activity.

Journal of Applied Meteorology, 2005, V44, N5, MAY,

pp 620-633

05.3-17

Modeling the influence of intermittent rain events

on long-term fate and transport of organic air

pollutants

Jolliet O, Hauschild M

Switzerland, Denmark

Hydrology , Modelling , Meteorology & Atmospheric

Sciences

The deposition of particles and substances in air is

under strong influence of the precipitation patterns of

the atmosphere. Most multimedia models, like type III

Mackay models, treat rain as a continuous phenomenon.

This may cause severe overestimation of the

substance removal from the atmosphere through wet

deposition and an underestimation of travel distances,

leading to the following questions: How strong is the

influence of the intermittent character of rain on concentrations,

residence times, deposited fractions, and

characteristic transport distances of different substances

in air? Is there an expression that can provide

an accurate approximation to be used in steady-state

multimedia models? Assuming a periodically intermittent

rain, the mass of an emitted substance that is

present in the air compartment is calculated as a

function of the deposition rate constants during dry

and wet periods and the durations of these periods. In

this paper, results for 300 different organic chemicals

are presented and illustrated in more detail for four

typical substances, showing the following: (i) Deposition

velocities can be up to 4 orders of magnitude

higher during rain events than during dry periods, especially

for persistent substances with low Henry constant.

(ii) For substances with a short reaction time

(residence time as determined by atmospheric degradation

alone) (e.g., propoxur) , the assumption of continuous

rain may lead to an underestimation of the atmospheric

residence time and travel distance by up to

3 orders of magnitude. For this group of substances,

the residence time during dry period provides a good

estimate of the overall atmospheric residence time.

(iii) For substances with reaction times close to the

duration of the dry period, the behavior is driven by

the length of the time interval between two rain


events, as for example, for methomyl. (iv) For very

persistent substances such as pentachloronitrobenzene

or carbon tetrachloride, the continuous rain approximation

provides a good estimate. On the basis of

these findings, an accurate but simple approximation

is provided by eq 17 for the incorporation of intermittent

rain behavior in steady-state multimedia models.

Environmental Science Technology, 2005, V39, N12,

JUN 15, pp 4513-4522

05.3-18

A composite study on the structure and formation

of ozone miniholes and minihighs over central

Europe

Koch G, Wernli H, Schwierz C, Staehelin J, Peter T

Switzerland, Germany

Meteorology & Atmospheric Sciences

( 1) Two different mechanisms have been proposed to

be important for the formation of extreme total ozone

events in mid-latitudes, so- called miniholes: ( A) farrange

meridional transport of air masses from regions

with different climatological ozone mixing ratios, and (

B) ( local) adiabatic vertical displacement of isentropes.

Here, the relative importance of these two

mechanisms is studied using two different ozone profile

reconstruction techniques for all miniholes and

minihighs ( events with anomalously high ozone) during

the time period 1980-1989 over Switzerland. Composites

for the two types of events of their vertical potential

vorticity ( PV) reveal a vertical dipole structure

of PV anomalies in the lower and middle stratosphere.

They, in agreement with the profile reconstructions,

highlight the importance of fast far-range transport (

mechanism A). Dynamically consistent with this PV

structure is a relatively weak vertical displacement of

isentropes between the PV dipole, that provides an

additional but less important contribution ( mechanism

B) .

Geophysical Research Letters, 2005, V32, N12,

JUN 23, ARTN: L12810

05.3-19

Design and field application of an automated

cartridge sampler for VOC concentration and flux

measurements

Kuhn U, Dindorf T, Ammann C, Rottenberger S,

Guyon P, Holzinger R, Ausma S, Kenntner T,

Helleis F, Kesselmeier J

Germany, Switzerland, Canada

Meteorology & Atmospheric Sciences

One of the major limitations in advancing the understanding

of tropospheric ozone and aerosol generation

and developing strategies for their control is the

technical ability to accurately measure volatile organic

compounds (VOCs). This paper describes the design

1.1 ATMOSPHERE

of a constant flow VOC sampler. The versatile sampler

can be used for fully automated concentration

and flux measurements of VOCs. The sampler incorporates

a microprocessor control unit and provides

highly accurate mass flow control and significant ease

of operation. Sampling sequences can be programmed

directly or by remote control through a PC. All

important operational parameters necessary for a

complete sampling audit trail are logged. Compact

weatherproof housings and low power consumption

allow operation at remote sites and locations which

are sensitive to disturbances or have restricted access.

Inner wetted surfaces of the sampler are constructed

from non-contaminating materials that do not

sorb or emit VOC, and thus permit the collection of

representative samples even in environments with

very low VOC concentrations. The cartridge magazine

provides a maximum of 20 sequential cartridge samples,

which allows for long- term air quality assessments.

In the dual channel mode, two samples can be

collected simultaneously through two independent

sample loops, providing ten sequential sample pairs.

This design allows the parallel collection of (a) quality

assurance backup samples, (b) samples on two different

types of cartridges/sorbents to allow a variety of

analyses, or (c) differential samples for flux measurements

using enclosure, aerodynamic profile, or relaxed

eddy accumulation (REA) methods. Field applications

including airplane profile measurements

above a tropical rainforest area, as well as gradient

and REA measurements over a mid-latitude mixed

forest stand are described, and demonstrate the validity

and flexibility of the system. In particular, the application

of the VOC sampler as an integrated part of a

REA system is emphasized.

Journal of Environmental Monitoring, 2005, V7, N6,

JUN, pp 568-576

05.3-20

Importance of submicron surface-active organic

aerosols for pristine Arctic clouds

Lohmann U, Leck C

Switzerland, Sweden

Meteorology & Atmospheric Sciences , Marine &

Freshwater Biology , Cryology / Glaciology ,

Oceanography

Recent results from summer measurement campaigns

over the partly ice covered central Arctic

Ocean show that the high Arctic aerosol has a larger

organic fraction than previously thought. We use a Lagrangian

parcel model to infer the properties of the

unexplained organic aerosol fraction that is necessary

for reproducing the observed concentrations of cloud

condensation nuclei (CCN). With increasing distance

from the open ocean a highly surface-active Aitken

mode, associated with particles found in the open

lead surface microlayer, becomes increasingly important

for cloud droplet formation. The presence of such

an Aitken mode population increases the high Arctic

Global Change Abstracts – The Swiss Contribution 25


indirect aerosol effect (added cooling) relative to just a

marine source of CCN from oxidation products of

dimethyl sulfide (DMS) released from phytoplankton.

Tellus Series B Chemical and Physical Meteorology,

2005, V57, N3, JUL, pp 261-268

05.3-21

A debiased ranked probability skill score to

evaluate probabilistic ensemble forecasts with

small ensemble sizes

Müller W A, Appenzeller C, Doblas Reyes F J,

Liniger M A

Switzerland, England

Meteorology & Atmospheric Sciences

The ranked probability skill score (RPSS) is a widely

used measure to quantify the skill of ensemble forecasts.

The underlying score is defined by the quadratic

norm and is comparable to the mean squared error

(mse) but it is applied in probability space. It is sensitive

to the shape and the shift of the predicted probability

distributions. However, the RPSS shows a negative

bias for ensemble systems with small ensemble

size, as recently shown. Here, two strategies are explored

to tackle this flaw of the RPSS. First, the RPSS

is examined for different norms L (RPSSL). It is

shown that the RPSSL=1 based on the absolute

rather than the squared difference between forecasted

and observed cumulative probability distribution is

unbiased; RPSSL defined with higher-order norms

show a negative bias. However, the RPSSL=1 is not

strictly proper in a statistical sense. A second approach

is then investigated, which is based on the

quadratic norm but with sampling errors in climatological

probabilities considered in the reference forecasts.

This technique is based on strictly proper scores and

results in an unbiased skill score, which is denoted as

the debiased ranked probability skill score (RPSSD)

hereafter. Both newly defined skill scores are independent

of the ensemble size, whereas the associated

confidence intervals are a function of the ensemble

size and the number of forecasts. The RPSSL-1 and

the RPSSD are then applied to the winter mean (December-January-February

(DJF)) near-surface temperature

predictions of the ECMWF Seasonal Forecast

System 2. The overall structures of the RPSSL=1

and the RPSSD are more consistent and largely independent

of the ensemble size, unlike the RPSSL-2.

Furthermore, the minimum ensemble size required to

predict a climate anomaly given a known signal-tonoise

ratio is determined by employing the new skill

scores. For a hypothetical setup comparable to the

ECMWF hindcast system (40 members and 15 hindcast

years), statistically significant skill scores were

only found for a signal- to-noise ratio larger than similar

to 0.3.

Journal of Climate, 2005, V18, N10, MAY 15,

pp 1513-1523, ISSN: 0894-8755

26

1.1 ATMOSPHERE

Global Change Abstracts – The Swiss Contribution

05.3-22

Adaptation of dry nephelometer measurements to

ambient conditions at the Jungfraujoch

Nessler R, Weingartner E, Baltensperger U

Switzerland

Meteorology & Atmospheric Sciences , Modelling

In a numerical study the influence of relative humidity

(RH) on aerosol scattering coefficients sigma was investigated.

Based on a core/coating aerosol model,

RH enhancement factors for scattering, xi (RH) = sigma(RH)/sigma(RH

= 0), were calculated for the wavelengths

lambda = 450, 550, and 700 nm for a summer

and a winter case. The investigation was adapted to

the situation (e.g., chemical composition, particle size

distributions, hygroscopic behavior) of the high-alpine

site Jungfraujoch (JFJ, 3580 m asl), where long-term

measurements of dry aerosol scattering coefficients

are performed at these wavelengths. The presented

results are therefore representative of the lower free

troposphere above a continent. The RH enhancement

factors at a specific RH strongly depend on the average

particle size. For example, at RH = 85% they vary

between similar to 1.2 and similar to 2.7 in summer

and between similar to 1.4 and similar to 3.8 in winter.

It is shown that there is a strong relationship between

and the Angstrom exponent 5 (based on scattering

only) of the dry aerosol, which is directly derived from

the dry scattering measurements. This allows for

parametrizing xi for a specific wavelength and season

with a and RH. The parametrization is applicable for

RH up to similar to 90%-for higher RH the underlying

hygroscopic models become unreliable-and for a between

similar to -0.25 and similar to 2.75, which covers

the range observed at the JFJ. Also addressed is

a systematic error in the dry scattering coefficients

measured with a nephelometer previously discussed

in the literature, which arises from nonidealities in the

angular intensity distribution of the light inside the instrument.

This effect also depends strongly on the

particle size and can be described by a correction factor

C that can be parametrized with a. The scattering

coefficient corrected for measurement artifacts at ambient

RH for specific wavelength and season therefore

can be estimated from the uncorrected dry nephelometer

scattering coefficient sigma(neph) as sigma(a,

RH) = C(a) x xi(a, RH) X sigma(neph). As additional

information only ambient RH data are needed.

The 95% confidence bound of this total correction

ranges from less than 5% for low RH and large a up

to similar to 40% for high RH and small A.

Environmental Science Technology, 2005, V39, N7,

APR 1, pp 2219-2228


05.3-23

Changes of daily surface ozone maxima in

Switzerland in all seasons from 1992 to 2002 and

discussion of summer 2003

Ordonez C, Mathis H, Furger M, Henne S, Huglin C,

Staehelin J, Prevot A S H

Switzerland

Meteorology & Atmospheric Sciences

An Analysis of Covariance (ANCOVA) was used to

derive the influence of the meteorological variability

on the daily maximum ozone concentrations at 12

low-elevation sites north of the Alps in Switzerland

during the four seasons in the 1992-2002 period. The

afternoon temperature and the morning global radiation

were the variables that accounted for most of the

meteorological variability in summer and spring, while

other variables that can be related to vertical mixing

and dilution of primary pollutants (afternoon global radiation,

wind speed, stability or day of the week) were

more significant in winter. In addition, the number of

days after a frontal passage was important to account

for ozone build-up in summer and ozone destruction

in winter. The statistical model proved to be a robust

tool for reducing the impact of the meteorological variability

on the ozone concentrations. The explained

variance of the model, averaged over all stations,

ranged from 60.2% in winter to 71.9% in autumn. The

year-to-year variability of the seasonal medians of

daily ozone maxima was reduced by 85% in winter,

60% in summer, and 50% in autumn and spring after

the meteorological adjustment. For most stations, no

significantly negative trends (at the 95% confidence

level) of the summer medians of daily O-3 or O-x

(O-3+NO2) maxima were found despite the significant

reduction in the precursor emissions in Central Europe.

However, significant downward trends in the

summer 90th percentiles of daily O-x maxima were

observed at 6 sites in the region around Zurich (on

average -0.73 ppb yr(-1) for those sites). The lower

effect of the titration by NO as a consequence of the

reduced emissions could partially explain the significantly

positive O-3 trends in the cold seasons (on average

0.69 ppb yr(-1) in winter and 0.58 ppb yr(-1) in

autumn). The increase of O-x found for most stations

in autumn (on average 0.23 ppb yr(-1)) and winter (on

average 0.39 ppb yr(-1)) could be due to increasing

European background ozone levels, in agreement

with other studies. The statistical model was also able

to explain the very high ozone concentrations in summer

2003, the warmest summer in Switzerland for at

least similar to 150 years. On average, the measured

daily ozone maximum was 15 ppb (nearly 29%) higher

than in the reference period summer 1992-2002,

corresponding to an excess of 5 standard deviations

of the summer means of daily ozone maxima in that

period.

Atmospheric Chemistry and Physics, 2005, V5,

MAY 25, pp 1187-1203

1.1 ATMOSPHERE

05.3-24

Atmospheric response to NOy source due to

energetic electron precipitation

Rozanov E, Callis L, Schlesinger M, Yang F,

Andronova N, Zubov V

Switzerland, USA, Russia

Modelling , Meteorology & Atmospheric Sciences

We have introduced additional NOy sources caused

by energetic electron precipitation (EEP) during 1987

into a Chemistry-Climate model. Comparison of two

model runs with and without EEP reveals increase of

reactive nitrogen by about 2 ppbv in the middle stratosphere

over the tropical and middle latitudes. In the

upper stratosphere over the polar winter regions the

simulated NOy enhancement reaches 10 ppbv. Decreases

of the ozone mixing ratio in the stratosphere

by up to 5% over midlatitudes and up to 30% over

southern high-latitudes are calculated. A similar to 0.5

K cooling in the middle stratosphere over the tropics

and up to 2 K over southern high-latitudes is calculated

with detectable changes in the surface air temperatures.

These results confirm that the magnitude of

the atmospheric response to EEP events can potentially

exceed the effects from solar UV fluxes. These

mechanisms work in phase outside polar latitudes,

but can compensate each other within polar latitudes.

Geophysical Research Letters, 2005, V32, N14,

JUL 22, ARTN: L14811

05.3-25

The heterogeneous interaction of HOCl with solid

KBr substrates: The catalytic role of adsorbed

halogens

Santschi C, Rossi M J

Switzerland

Chemistry , Meteorology & Atmospheric Sciences

The heterogeneous reactivity of HOCl on solid KBr at

ambient temperature has been studied using a Knudsen.

ow reactor. On solid KBr steady-state uptake experiments

reveal the formation of Br- and Cl- containing

reaction products formed in secondary reactions

such as Br-2, BrCl, HOBr, BrOCl, Cl-2 and Cl2O with

the latter two predominating in the late stages of the

reaction. The uptake coeffcient gamma spanning a

range between 0.15 and 1 x 10(-3) and product yields

of HOCl strongly depend on the nature of the solid

sample, whether grain, ground grain or thin sprayed

film, as well as on sample processing such as pumping

and/ or heating. Furthermore, the presence of adsorbed

halogen species such as Br-2( a) are crucial

for the kinetics of the reaction of HOCl with solid KBr

substrates. The presence of surface-adsorbed water

(SAW) leads to deactivation of KBr whereas mechanical

stress such as grinding leads to the formation of

surface defects that become reaction centers. Des-

Global Change Abstracts – The Swiss Contribution 27


orption of SAW at T > 620 K induces high reactivity of

the KBr sample at ambient temperature. A reaction

mechanism encompassing all signicant observations

including unusual autocatalytic activity is given as

there is no direct reaction of HOCl with solid KBr. It

stresses the importance of adsorbed Br- containing

species such as Br-2( a) and HBr( a) that initiate the

heterogeneous chemistry of HOCl on solid KBr in the

presence of SAW. The role of surface acidity and

SAW for the extent of reaction is emphasized.

Physical Chemistry Chemical Physics, 2005, V7, N13,

pp 2599-2609

05.3-26

Trends of heavy precipitation and wet and dry

spells in Switzerland during the 20th century

Schmidli J, Frei C

Switzerland

Meteorology & Atmospheric Sciences , Hydrology

The low-frequency variability of heavy precipitation

and drought conditions is investigated for 104 raingauge

stations in Switzerland covering the 20th century.

This constitutes an exceptionally dense data set

of centennial time series. The investigation is based

on a wide range of daily and multi-day precipitation

statistics encompassing basic characteristics, measures

of heavy precipitation and indices of typical and

extreme dry and wet spells. Two different methods of

trend analysis and statistical testing are applied, depending

on the data nature of the statistic. Linear regression

is used for statistics with a continuous value

range, and logistic regression is used for statistics

with a discrete value range. The trends are calculated

on a seasonal basis for the years 1901-2000. A clear

trend signal is found for winter and autumn, with a

high number of sites with a statistically significant

trend. In winter, significant increases are found for all

statistics related to precipitation strength and occurrence.

The centennial increase is between 10 and

30% for the high quantiles and the seasonal 1 day to

10 day extremes. In autumn, statistically significant increases

are found only for the statistics related to

heavy precipitation, whereas precipitation frequency

and spell-length statistics show little systematic

change. Although the winter trend signal is strongest

in northern and western Switzerland, the autumn

trend signal is more uniform. In spring and summer,

the heavy precipitation and the spell- duration statistics

did not show statistically significant trends. Sensitivity

tests indicate that the winter and autumn trends

are robust with respect to inhomogeneities in the raingauge

time series.

International Journal of Climatology, 2005, V25, N6,

MAY, pp 753-771

28

Global Change Abstracts – The Swiss Contribution

1.1 ATMOSPHERE

05.3-27

Special characteristics of the temperature

structure near the surface

Sodemann H, Foken T

Switzerland, Germany

Meteorology & Atmospheric Sciences

Detailed analyses of air temperature profiles measured

over the Antarctic shelf ice revealed the frequent presence

of an inversion layer in the lower 2 in above

ground. The regular character of the phenomenon allowed

for an in-depth description of its diurnal evolution

and long-term behavior. From additional high-resolution

temperature profile measurements it was observed that

the inversion layer leads to a decoupling of the surface

layer heat fluxes from the radiative surface temperature.

It is demonstrated that bulk parameterizations are not

able to provide valid predictions of turbulent heat fluxes

under such conditions. A model with a three- layer temperature

profile is shown to give useful estimates for the

aerodynamic temperature, even in the presence of an

inversion layer near the surface. This indicates a possible

approach to address the limitations of current bulk

parameterizations for heat fluxes in high latitudes.

Theoretical and Applied Climatology, 2005, V80,

N2-4, APR, pp 81-89

05.3-28

An airborne radiometer for stratospheric water

vapor measurements at 183 GHz

Vasic V, Feist D G, Müller S, Kämpfer N

Switzerland

Meteorology & Atmospheric Sciences , Hydrology

The Airborne Millimeter- and Submillimeter Observing

System (AMSOS) is a total-power radiometer for observations

of the 183.3-GHz water vapor rotational line, operated

onboard a Learjet aircraft of the Swiss Air Force.

The radiometer is also used to observe the 175.45-

GHz ozone line in the other sideband. The neatly designed

quasi optics provide a regular and narrow output

beam with a half-power beam-width angle of 1.2 degrees

and efficient sideband switching. A lambda/4quasi-optical

isolator is used for baseline reduction securing

attenuation of internal reflections by more than

30 dB. A low noise temperature of the ambient-temperature-operating

system (1900 K) and excellent target

pointing (better than OX) provide a good duty cycle and

reliable calibration. A reliable control over the radiometer's

operational parameters, like system stability and

system temperatures, and higher automatization were

required to come up with high demands of an onboard

operation. The measured spectra look typical for the region

and time where they were observed.

Ieee Transactions on Geoscience and Remote

Sensing, 2005, V43, N7, JUL, pp 1563-1570


05.3-29

Generation of submicron Arizona test dust

aerosol: Chemical and hygroscopic properties

Vlasenko A, Sjogren S, Weingartner E,

Gäggeler H W, Ammann A

Switzerland

Meteorology & Atmospheric Sciences

This article describes a submicron dust aerosol generation

system based on a commercially available

dust disperser intended for use in laboratory studies

of heterogeneous gas-aerosol interactions. Mineral

dust particles are resuspended from Arizona Test

Dust (ATD) powder as a case study. The system output

in terms of number and surface area is adjustable

and stable enough for aerosol flow reactor studies.

Particles produced are in the 30-1000 nm size range

with a lognormal shape of the number size distribution.

The particles are characterized with respect to

morphology, electrical properties, hygroscopic properties,

and chemical composition. Sub-micron particle

elemental composition is found to be similar for the

particle surface and bulk as revealed by X-ray photoelectron

spectroscopy (XPS) and inductively coupled

plasma optical emission spectroscopy (ICP-OES), respectively.

A significant difference in chemical composition

is found between the submicron aerosol and the

ATD bulk powder from which it was generated. The

anionic composition of the water-soluble fraction of

this dust sample is dominated by sulfate. Resuspended

dust particles show, as expected, nonhygroscopic

behavior in a humid environment. Small hygroscopic

growth of about 1% (relative change in mobility diameter)

was observed for 100 nm particles when the relative

humidity (RH) was changed from 12 to 94%.

Particles larger than 100-200 nm shrank about 1%

once exposed to RH > 90%. This was interpreted

as a restructuring of the larger agglomerates of dust

to particles of smaller mobility diameter, under the influence

of water vapor.

Aerosol Science and Technology, 2005, V39, N5,

MAY, pp 452-460

05.3-30

Nitric Acid Trihydrate (NAT) formation at low NAT

supersaturation in Polar Stratospheric Clouds

(PSCs)

Voigt C, Schlager H, Luo B P, Dornbrack A D,

Roiger A, Stock P, Curtius J, Vossing H, Borrmann S,

Davies S, Konopka P, Schiller C, Shur G, Peter T

Germany, Switzerland, England, Russia

Meteorology & Atmospheric Sciences

A PSC was detected on 6 February 2003 in the Arctic

stratosphere by in-situ measurements onboard the

1.1 ATMOSPHERE

high-altitude research aircraft Geophysica. Low number

densities (similar to 10(-4) cm(-3)) of small nitric

acid (HNO3) containing particles (d< 6 µm) were observed

at altitudes between 18 and 20 km. Provided

the temperatures remain below the NAT equilibrium

temperature TNAT, these NAT particles have the potential

to grow further and to remove HNO3 from the

stratosphere, thereby enhancing polar ozone loss. Interestingly,

the NAT particles formed in less than a

day at temperatures just slightly below T-NAT ( T> T-

NAT- 3.1 K). This unique measurement of PSC formation

at extremely low NAT saturation ratios (S-NAT

less than or similar to 10) constrains current NAT nucleation

theories. We suggest, that the NAT particles

have formed heterogeneously, but for certain not on

ice. Conversely, meteoritic particles may be favorable

candidates for triggering NAT nucleation at the observed

low number densities.

Atmospheric Chemistry and Physics, 2005, V5,

JUN 8, pp 1371-1380

05.3-31

Integrated equivalent latitude as a proxy for

dynamical changes in ozone column

Wohltmann I, Rex M, Brunner D, Mader J

Germany, Switzerland

Meteorology & Atmospheric Sciences , Modelling

It is well known that short-term variability in ozone column

at a given location is almost solely caused by dynamical

changes connected to tropospheric pressure

systems. Long-term trends and interannual variability

of ozone are also influenced by these dynamical

changes. We address two questions, which are still

under discussion: What is the impact of these dynamical

changes on the observed long-term trend of

ozone, and what is the quantitative contribution of the

physical processes standing behind the dynamical

variability to the trends and short-term variability?

These processes are identified as horizontal isentropic

transport and the vertical displacement of isentropes.

We use a multiple regression model to analyze

the variability of the total ozone column. The

model includes a newly introduced explanatory variable

based on the equivalent latitude profile at a given

location. Ozone column data are taken from 8 high

quality stations of the European Dobson spectrometer

network. Results show that vertical displacements are

the main contributor to short-term variability, and that

30% - 50% of the long-term trend can be explained by

long-term pressure changes.

Geophysical Research Letters, 2005, V32, N9,

MAY 13, ARTN: L09811

Global Change Abstracts – The Swiss Contribution 29


05.3-32

Responses of net ecosystem CO2 exchange in

managed grassland to long- term CO2 enrichment,

N fertilization and plant species

Aeschlimann U, Nösberger J, Edwards P J,

Schneider M K, Richter M, Blum H

Switzerland, England

Agriculture, Soil Sciences , Plant Sciences

The effects of elevated pCO(2) on net ecosystem CO2

exchange were investigated in managed Lolium

perenne (perennial ryegrass) and Trifolium repens

(white clover) monocultures that had been exposed

continuously to elevated pCO(2) (60 Pa) for nine

growing seasons using Free Air CO2 Enrichment

(FACE) technology. Two levels of nitrogen (N) fertilization

were applied. Midday net ecosystem CO2 exchange

(mNEE) and night-time ecosystem respiration

(NER) were measured in three growing seasons using

an open-flow chamber system. The annual net

ecosystem carbon (C) input resulting from the net

CO2 fluxes was estimated for one growing season. In

both monocultures and at both levels of N supply, elevated

pCO(2) stimulated mNEE by up to 32%, the exact

amount depending on intercepted PAR. The response

of m NEE to elevated pCO(2) was larger than

that of harvestable biomass. Elevated pCO(2) increased

NER by up to 39% in both species at both

levels of N supply. NER, which was affected by mNEE

of the preceding day, was higher in T. repens than in

L. perenne. High N increased NER compared to low

N supply. According to treatment, the annual net

ecosystem C input ranged between 210 and 631 g C

m(-2) year(-1) and was not significantly affected by

the level of pCO(2). Low N supply led to a higher net

C input than high N supply. We demonstrated that at

the ecosystem level, there was a long-term stimulation

in the net C assimilation during daytime by elevated

pCO(2). However, because NER was also stimulated,

net ecosystem C input was not significantly increased

at elevated pCO(2). The annual net ecosystem

C input was primarily affected by the amount of N

supplied.

Plant Cell and Environment, 2005, V28, N7, JUL,

pp 823-833

05.3-33

Are ecological compensation areas attractive

hunting sites for common kestrels (Falco

tinnunculus) and long-eared owls (Asio otus)?

Aschwanden J, Birrer S, Jenni L

Switzerland

Ecology , Zoology , Agriculture, Soil Sciences ,

Biodiversity

Common kestrels (Falco tinnunculus) and long-eared

owls (Asio otus) in intensively farmed areas in

30

1.2 Terrestrial Ecosystems

Global Change Abstracts – The Swiss Contribution

Switzerland decreased markedly as a result of declining

vole (Microtus spp.) populations. In order to counteract

the loss of biodiversity in intensively farmed areas,

the Swiss agri-environment scheme stipulates

several types of ecological compensation areas,

which together should take up 7% of the farmland.

Among them are wild flower and herbaceous strips,

which are not mown every year and which in summer

support up to 8 times more small mammals than ordinary

fields and grassland. This study investigates

whether kestrels and long-eared owls preferentially

hunt on ecological compensation areas and whether

preferred hunting areas are related to the density of

small mammals or to the density and height of the

vegetation. Both kestrels and long-eared owls mainly

hunted on freshly mown low-intensity meadows and

artificial grassland, despite low densities of small

mammals. Therefore, vegetation structure was more

important for the selection of hunting sites than prey

abundance. However, both predators preferred to

hunt on freshly mown grassland and meadows bordering

a wild flower or herbaceous strip. Voles from

these strips probably invaded the adjacent freshly

mown grassland and became an easy prey for

kestrels and owls. In intensively farmed regions, ecological

compensation areas, particularly those not

mown each year, are an important refuge for small

mammals, although in summer the small mammals

are not directly accessible to hunting birds. Hence, a

mosaic of different habitat types with grassland mown

at different times of the year together with undisturbed

strips is best suited to provide a year-round supply of

accessible food for vole hunters.

Journal of Ornithology, 2005, V146, N3, JUL,

pp 279-286

05.3-34

Carabid assemblages in agricultural landscapes:

impacts of habitat features, landscape context at

different spatial scales and farming intensity

Aviron S, Burel F, Baudry J, Schermann N

France, Switzerland

Agriculture, Soil Sciences , Ecology , Biodiversity ,

Zoology

Agricultural intensification has led to a major loss of

biodiversity, as a consequence of the reduction of permanent

landscape elements and the increasing use of

inputs. Few studies have considered simultaneously

habitat features, landscape pattern and farming systems

to explain the changes in biodiversity of agricultural

landscapes. This study investigated the respective

effects of habitat type, landscape context of habitats

and farming intensity on carabid beetles assemblages

in hedgerow network landscapes in western

France. Carabid beetles were sampled in various permanent

landscape elements in three 25 km(2) landscape

units of contrasting structural complexity and


farming systems. The respective importance of habitat

type, landscape context and landscape unit were

investigated using canonical correspondence analysis

(CCA) and partial CCA. The landscape units were the

most important variables constraining carabid assemblages

(10.3% of variance explained), followed by

habitat type (9.3% of variance explained) and, to a

lesser extent, by landscape context characteristics

(3.9% of variance explained). Large forest species of

low mobility were less abundant in landscape units

with intensive farming systems and a reduced network

of permanent elements. Carabid communities

also differed among habitat types, i.e. woodlands and

field boundaries. Landscape context characteristics

had a low but significant influence on carabid assemblages,

forest species being less frequent in landscape

contexts with low amounts of woodland and

hedgerows. Our results underline the need to consider

the relationships between farming systems and

landscape pattern for the conservation of carabid diversity

in agricultural landscapes. Both the design of

suitable habitat at the landscape scale and changes

in farming systems should be considered in agri-environmental

policies for the conservation of biodiversity

in agricultural landscapes.

Agriculture Ecosystems Environment, 2005, V108,

N3, JUN 30, pp 205-217

05.3-35

Behavioral constancy for interspecies dependency

enables Nearctic Chymomyza amoena (Loew)

(Diptera : Drosophilidae) to spread in orchards

and forests in Central and Southern Europe

Band H T, Bachli G, Band R N

USA, Switzerland

Zoology , Forestry , Plant Sciences , Biodiversity

Nearctic Chymomyza amoena, an eastern US forest

drosophilid, was initially known only to breed in damaged

or parasitized nuts and had been little studied. It

has been spreading in Europe since its discovery in

the former Czechoslovakia in 1975. By the time it arrived

in Switzerlands Canton Ticino in 1988, research

in the United States revealed it had long been in domestic

habitats, overwinters in the third instar larval

stage in endemic substrates (black walnut husks

Juglans nigra, native crabapples Malus coronaria),

domestic (imported) apples Malus domestica and ornamental

fruits (crabapples) and uses these plus other

substrates for breeding from spring and summer

through autumn. Female oviposition in firm substrates

in Michigan and the mid-South (North Carolina, Virginia)

as fallen unripe and ripe frassy apples, acorns,

black walnut husks, native and ornamental crabapples

is mediated by prior insect attack. Although large

numbers of C. amoena coming to banana bait in Canton

Ticino suggested that founder effects involving attraction

to fermenting substrates might have occurred,

experimental studies with European flies in Michigan

1.2 TERRESTRIAL ECOSYSTEMS

and continuing research in Zurich and Canton Ticino

revealed that behavioral constancy had been maintained.

This enabled prediction that C. amoena would

spread into apple orchards in northern Switzerland

and into Italy. Research in July 2000 established that

it is in apple orchards on the German border and in

the chestnut forests and in old orchard apples in Italys

Valtellina region, Lombardy Province. Other European

drosophilids have not exploited parasitized fruits and

nuts, indicating C. amoena entered a vacant niche.

Facilitation provided by pest species attacking fruit

and nut substrates parallel those in North America.

Chymomyza amoena has maintained behavioral constancy

for interspecies dependency and continues to

be the principal drosophilid breeding in parasitized

fruits and nuts in both North America and Europe.

Biological Invasions, 2005, V7, N3, MAY, pp 509-530

05.3-36

Diversity and genetic structure of the wood ant

Formica lugubris in unmanaged forests

Bernasconi C, Maeder A, Cherix D, Pamilo P

Switzerland, Finland

Forestry , Biodiversity , Zoology , Ecology

Wood ant species show differences in their social

structure, especially in the level of polygyny (number

of laying queens per nest) and polydomy (number of

nest per colony), both within and between species.

We demonstrate here for the first time that Formica

lugubris displays two different social forms in close

proximity in alpine unmanaged forests of the Swiss

National Park. The genetic data (7 microsatellite loci)

and field data indicate that one population is mostly

monogynous to weakly polygynous (r = 0.438) and

monodomous, the second one being polygynous (r =

0.113) and polydomous. Within this latter population

new nests are founded by budding, leading to the observed

high density of nests. These two different social

structures, possibly being two expressions of a

same continuum, could be explained by several ecological

or environmental factors (e.g. habitat saturation,

resource competition) and also historical effects.

Annales Zoologici Fennici, 2005, V42, N3, JUN 28,

pp 189-199

05.3-37

Simulating complex landscapes with a generic

model: Sensitivity to qualitative and quantitative

classifications

Bolliger J

Switzerland

Modelling , Forestry , Ecology

The sensitivity of a generic cellular automaton model

to qualitative and quantitative landscape classifica-

Global Change Abstracts – The Swiss Contribution 31


tions is tested regarding the spatio-temporal self-organization

of the historical landscape pattern of southern

Wisconsin (USA). The qualitative classification is R.W.

Finley's "Original Vegetation of Wisconsin" and relies

on criteria determined by an expert individual. The

classification accounts for descriptive information and

expert knowledge, but is not easily reproducible due

to locally subjective decisions of class delineations.

The quantitative classifications rely on a numericalobjective

algorithm that ensures classification reproducibility

and tests for robustness, but do not account

for local ecosystem knowledge or qualitative detail.

For model development, a cell in the forest-landscape

lattice is chosen according to three generic and

stochastic rules. The uncorrelated" rule chooses a cell

randomly, the "correlated" rule picks a cell within two

distances of random length, and the raster" rule

chooses randomly one of four immediate neighbors in

the lattice. The so chosen cell is then replaced by a

cell randomly identified within a circular neighborhood

of radius r (1 < r < 10). Comparisons between model

simulations and the empirical forest landscapes include

temporal dynamics (cluster probability) and spatial

patterns (fractal dimension, landscape diversity).

Results suggest that the simulated landscape (1) exhibits

self-organization for intermediate neighborhoods

(r = 3), independent of the classification approach,

three model-development rules, and two initial

and boundary conditions; (2) achieves temporal

(cluster probability) dynamics and spatial patterns

(fractal dimension, landscape diversity) consistent

with the empirical landscape. It is, therefore, concluded

that a generic model calibrated independently from

specific ecological processes may suffice to replicate

major statistical characteristics of a complex landscape

with simulations that are robust to various landscape-classification

approaches.

Ecological Complexity, 2005, V2, N2, JUN,

pp 131-149

05.3-38

Simulating the spatial and temporal dynamics of

landscapes using generic and complex models

Bolliger J, Lischke H, Green D G

Switzerland, Australia

Urban Studies , Modelling , Ecology

Landscape patterns originate from exogenous (e.g.,

climate) and endogenous (e.g., competition) processes

and feedbacks that interact spatially and temporally.

The resulting dynamics can be analyzed and quantified

using spatio-temporal models. Various approaches

are currently in use, ranging from generic to

process-oriented models. However, strict classifications

are difficult as models can be characterized by

many different criteria. One important distinction is

structural complexity. This may manifest itself in: (1)

conceptual complication of the modelling approach,

(2) the translation of the system complexity into model

formalism, and (3) the level of detail of the simulated

32

Global Change Abstracts – The Swiss Contribution

1.2 TERRESTRIAL ECOSYSTEMS

output. Thus, process models that mirror systems by

quantifying individual biotic and/or abiotic processes

may be referred to as complex models since their

simulated output usually identifies explicit system details

that require many input parameters mirroring the

system bottom-up. Generic models, on the other

hand, tend to be structurally parsimonious, usually not

accounting for specific system details. They are often

applied to study topics of complex systems theory

such as emergence, self-organization, scaling, and

chaos theory, and involving techniques used in nonlinear

dynamical systems theory. This special issue

identifies concepts and methods used by models to

represent spatially dynamic landscape patterns. It assesses

relationships between landscape and model

complexity, and discusses approaches to quantify the

spatio-temporal pattern dynamics resulting from model

simulations. The models presented here address a

variety of different research topics, including climate

change, urban development, ecological engineering,

landscape classification concepts, spatial population

dynamics, habitat fragmentation, and conservation.

The models account for different biotic levels (individual,

population, vegetation patterns), and are driven

by both exogenous and endogenous processes. Identification

and quantification of the landscape patterns

produced by the simulated output relies on various indicators.

Discrete-static indicators include landscape

metrics. Static pattern descriptions involve fractal dimensions,

whereas dynamic indicators include power

spectra, entropy, or indicators of patch aggregation.

Thematically, this special issue contributes to a variety

of key topics in landscape ecology, including consideration

of anthropogenic impacts on landscapes, or

holistic approaches such as self- organization, or the

governing role of connectivity in shaping ecological

systems.

Ecological Complexity, 2005, V2, N2, JUN,

pp 107-116

05.3-39

Ranking protected areas in the Azores using

standardised sampling of soil epigean arthropods

Borges P A V, Aguiar C, Amaral J, Amorim I R, Andre G,

Arraiol A, Baz A, Dinis F, Enghoff H, Gaspar C,

Ilharco F, Mahnert V, Melo C, Pereira F, Quartau J A,

Ribeiro S P, Ribes J, Serrano A R M, Sousa A B,

Strassen R Z, Vieira L, Vieira V, Vitorino A,

Wunderlich J

Portugal, USA, Spain, Denmark, England,

Switzerland, Brazil, Germany

Forestry , Plant Sciences , Zoology , Agriculture, Soil

Sciences , Biodiversity

Nineteen areas in seven of the nine Azorean islands

were evaluated for species diversity and rarity based

on soil epigean arthropods. Fifteen out of the 19 study

areas are managed as Natural Forest Reserves and

the remaining four were included due to their importance

as indigenous forest cover. Four of the 19 areas


are not included in the European Conservation network,

NATURA 2000. Two sampling replicates were

run per study area, and a total of 191 species were

collected; 43 of those species (23%) are endemic to

the archipelago and 12 have yet to be described. To

produce an unbiased multiple- criteria index (importance

value for conservation, IV-C) incorporating diversity

and rarity based indices, an iterative partial

multiple regression analysis was performed. In addition,

an irreplaceability index and the complementarity

method (using both optimisation and heuristic methods)

were used for priority-reserves analyses. It was

concluded that at least one well-managed reserve per

island is absolutely necessary to have a good fraction

of the endemic arthropods preserved. We found that

for presence/absence data the suboptimal complementarity

algorithm provides solutions as good as the

optimal algorithm. For abundance data, optimal solutions

indicate that most reserves are needed if we

want that at least 50% of endemic arthropod populations

are represented in a minimum set of reserves.

Consistently, two of the four areas not included in the

NATURA 2000 framework were considered of high

priority, indicating that vascular plants and bird

species used to determine NATURA 2000 sites are

not good surrogates of arthropod diversity in the

Azores. The most irreplaceable reserves are those located

in older islands, which indicates that geological

history plays an important role in explaining faunal diversity

of arthropods in the Azores. Based both on the

uniqueness of species composition and high species

richness, conservation efforts should be focused on

the unmanaged Pico Alto region in the archipelago's

oldest island, Santa Maria.

Biodiversity and Conservation, 2005, V14, N9, AUG,

pp 2029-2060

05.3-40

Persistent organic pollutants in source-separated

compost and its feedstock materials - A review of

field studies

Brändli R C, Bucheli T D, Kupper T, Furrer R, Stadelmann

F X, Tarradellas J

Switzerland, USA

Agriculture, Soil Sciences , Geochemistry & Geophysics

Composting and the application of compost to the soil

follow the principle of recycling and sustainability.

Compost can also have a positive effect on physical,

chemical, and biological soil parameters. However, little

is known about the origin, concentration, and

transformation of persistent organic pollutants (POPs)

in compost. We therefore compiled literature data on

some priority POPs in compost and its main feedstock

materials from more than 60 reports. Our data evaluation

suggests the following findings. First, median

concentrations of Sigma 16 polycyclic aromatic hydrocarbons

(PAHs), 16 polychlorinated biphenyls (PCBs),

and Sigma 17 polychlorinated dibenzo-p-dioxins and -

1.2 TERRESTRIAL ECOSYSTEMS

furans (PCDD/Fs) were higher in green waste (1803,

15.6 µg/kg dry wt., and 2.5 ng international toxicity

equivalent (I-TEQ)/kg dry wt.) than in organic household

waste (635, 14.6 µg/kg dry wt., and 2.2 ng I-

TEQ/kg dry wt.) and kitchen waste (not available

(NA), 14.9 µg/kg dry wt., 0.4 ng I-TEQ /kg dry wt.).

The POP concentrations in foliage were up to 12

times higher than in other feedstock materials. Second,

in contrast, compost from organic household

waste and green waste contained similar amounts of

Sigma 16 PAHs, 16 PCBs, and Sigma 17 PCDD/Fs

(1915, 39.8 µg/kg dry wt., and 9.5 ng I-TEQ/kg dry

wt., and 1715, 30.6 µg/kg dry wt., and 8.5 ng I-

TEQ/kg dry wt., respectively). Third, concentrations of

three-ring PAHs were reduced during the composting

process, whereas five- to six-ring PAHs and Sigma 6

PCBs increased by roughly a factor of two due to

mass reduction during composting. Sigma PC DD/Fs

had accumulated by up to a factor of 14. Fourth, urban

feedstock and compost had higher POP concentrations

than rural material. Fifth, the highest concentrations

of POPs were usually observed in summer

samples. Finally, median compost concentrations of

POPs were greater by up to one order of magnitude

than in arable soils, as the primary recipients of compost,

but were well within the range of many urban

soils. In conclusion, this work provides a basis for the

further improvement of composting and for future risk

assessments of compost application.

Journal of Environmental Quality, 2005, V34, N3,

MAY-JUN, pp 735-760

05.3-41

Surface runoff and transport of sulfonamide

antibiotics and tracers on manured grassland

Burkhardt M, Stamm C, Waul C, Singer H, Müller S

Switzerland, Denmark

Toxicology, Geochemistry & Geophysics, Hydrology,

Agriculture, Soil Sciences

Despite their common use in animal production the

environmental fate of the veterinary sulfonamide antibiotics

after excretion is only poorly understood. We

performed irrigation experiments to investigate the

transport of these substances with surface runoff on

grassland. Liquid manure from pigs treated with sulfadimidine

was spiked with sulfadiazine, sulfathiazole,

the herbicide atrazine (2-chloro-4- ethylamino-6-isopropylamino-1,3,5-triazine),

and the conservative tracer

bromide and spread onto eight plots. Four plots received

the same amounts of the spiked substances in

aqueous solution (controls). Apart from the application

matrix we varied the time between application and irrigation.

Manure increased the runoff volume up to six

times compared with the controls. It seemed that manure

enhanced the runoff by sealing the soil surface.

On manured plots the relative antibiotic concentrations

in runoff were higher than on the controls, reaching

an average of 0.3% (sulfadiazine), 0.8% (sulfathiazole),

and' 1.4% (sulfadimidine) of the input concen-

Global Change Abstracts – The Swiss Contribution 33


trations after a 1-d contact time. The corresponding

values on the controls were 0.16% for sulfadiazine

and 0.08% for sulfathiazole. After 3 d, the maximum

values on the manured plots were even higher,

whereas they had fallen below the limit of quantification

on the controls. As a consequence, the sulfonamide

losses were 10 to 40 times larger on the manured

plots. The relative mobility of the sulfonamides

on the control plots followed the trend expected from

their chromatographic separation but the opposite

was found on the manured plots. Hence it is important

to consider explicitly the physical and chemical effects

of manure when assessing the environmental fate of

sulfonamides.

Journal of Environmental Quality, 2005, V34, N4,

JUL-AUG, pp 1363-1371

05.3-42

The effect of slug grazing on vegetation

development and plant species diversity in an

experimental grassland

Buschmann H, Keller M, Porret N, Dietz H,

Edwards P J

Switzerland

Zoology , Agriculture, Soil Sciences , Plant Sciences ,

Biodiversity

1. Generalist herbivores such as slugs have the potential

not only to reduce plant density and biomass,

but also to alter species diversity within vegetation.

Their impact on species diversity may be either negative,

if they concentrate feeding on less abundant

plant species, or positive, if they feed on the most

abundant species. 2. This study investigated the influence

of slugs on plant species diversity in experimental

swards produced by sowing a Lolium perenne /Trifolium

repens seed mixture in field plots with a large

seed bank of mainly arable species. Half of the plots

were grazed by Arion lusitanicus Mabille. Plant cover,

above-ground biomass and number of plant species

were measured over a 3-year period. 3. Vegetation

cover increased in the control plots from 50% in the

first year to 90% in the third year. Cover was significantly

lower in the slug plots in the first year (> 22%),

while there were only small differences between treatments

in the third year. Slugs reduced total aboveground

biomass by > 25% in both the first and third

years. 4. Slugs had a negative impact on plant

species diversity in the first year, particularly by reducing

forb species. In contrast, plant species diversity

after 3 years was higher in the slug plots than in the

controls, because of the higher number of forb

species. Under slug grazing, the biomass and cover

of annual and palatable species were reduced, but

not the numbers of these species. 5. Our results suggest

that slugs can have a significant effect on plant

species diversity in plant communities, but that the direction

of the effect changes during the course of succession.

In the earliest stages, when most species are

present as seedlings or juveniles, slug grazing leads

34

1.2 TERRESTRIAL ECOSYSTEMS

Global Change Abstracts – The Swiss Contribution

to reduced species diversity because favoured

species are eliminated. In closed vegetation, in which

competitive interactions are important, slugs may reduce

the dominance of the more competitive species

and thus provide gaps in which plants can establish

from seed. As a consequence, slugs tend to cause an

increase in plant species diversity, and may also reduce

the rate of successional change by promoting

the persistence of annual species.

Functional Ecology, 2005, V19, N2, APR, pp 291-298

05.3-43

Phytophenological trends in the Swiss Alps,

1951-2002

Defila C, Clot B

Switzerland

Meteorology & Atmospheric Sciences , Plant

Sciences

This work aims to study the long term phenological

trends in Switzerland and is focused upon the differences

between the lowland (lower than 600 m asl)

and the alpine regions (higher than 1000 m asl) for

the 1951-2002 period. Trends for 651 time series (n

>= 30 years) from 75 observation stations and 19

phenophases were calculated. Compared to the results

obtained with the dataset 1951-1998, the proportion

of the significant trends like the intensity of the

trends calculated in days have been reinforced. In every

season, a general earlier occurrence of the

phenophases has been observed, except by the leaf

fall, where a slight delay is more likely to occur. The

proportion of significant trends is clearly higher in the

alpine regions (42 %) than in the lowland (33 %). On

the contrary, the shift towards earlier occurrences is

stronger in the lowland. The spring phenophases occur

20 days in advance in the lowland and 15 days in

the alpine regions, in summer 19 and 16 days, and in

autumn 7 and 4 days earlier in the lowland and the

alpine regions respectively. The proportion of significant

trends in the regions located in the south of the

Alps is remarkable: 64 % in the lowland and 50 % in

the alpine regions. In this area, the small number of

data only allowed the study of the leaf unfolding and

the full flowering. Concerning the full flowering, an advance

of 32 days in the lowland and 20 days in the

alpine regions was observed. The leaf unfolding occurred

12 days earlier in the lowland and 1 day later

in the alpine regions than 50 years before. The trends

concerning the full flowering present a stronger trend

in the south than in the north of the Alps. On the contrary,

the trends concerning the leaf unfolding are

stronger in the north. In Switzerland, the climate

warming was stronger in the last decades than the

global one. The increase in temperature reaches 1.5

degrees for 100 years in winter and 0.4 to 0.8 in summer

for the 1864 to 2001 period. As it was several

times mentioned, the spring and early summer

phenophases are above all influenced by the temperature

of the air. Then the trend towards earlier occur-


ence of the phenological phases is clearly related to

the climate warming. In autumn, apart from the temperature,

other parameters such as dry periods during

the vegetation period play also an important role.

Short time weather events such as strong winds, frost

or snow fall are the main drivers of the leaf fall. This

study gives prominence that phenology is a good indicator

of the influences of a climate warming on the

development of the vegetation. Strong regional and

altitudinal differences are observed in Switzerland.

Meteorologische Zeitschrift, 2005, V14, N2,

pp 191-196

05.3-44

Model-based stratifications for enhancing the

detection of rare ecoligical events

Edwards T C, Cutler D R, Zimmermann N E, Geiser L,

Alegria J

USA, Switzerland

Modelling , Biodiversity , Ecology , Geomorphology ,

Meteorology & Atmospheric Sciences , Plant

Sciences

A common concern when designing surveys for rare

species is ensuring sufficient detections for analytical

purposes, such as estimating frequency on the landscape

or modeling habitat relationships. Strict designbased

approaches provide the least biased estimates

but often result in low detection rates of rare species.

Here, we demonstrate how model-based stratification

can improve the probability of detecting five rare epiphytic

macrolichens (Nephroma laevigatum, N. occultum,

N. parile, Lobaria scrobiculataa, and Psuedocyphelaria

rainierensis) in the Pacific Northwest. We

constructed classification tree models for four more

common lichens (L. oregana, L. pulmonaria, P.

anomala, and P. anthraspis) that are associated with

the rare species, then used the models to generate

strata for sampling for the five lichen species considered

rare. The classification tree models were developed

using topographic and bio-climatic variables hypothesized

to have direct relationships to the presence

of the modeled lichen species. When the expected

detection rates using the model-based stratification

approach was tested on an independent data

set, it resulted in two- to fivefold gains in detection

compared to the observed detection rates for four of

the five tested rare species.

Ecology, 2005, V86, N5, MAY, pp 1081-1090

05.3-45

Differences in surface roughness, energy, and

CO2 fluxes in two moist tundra vegetation types,

Kuparuk watershed, Alaska, USA

Eugster W, Mcfadden J P, Chapin F S

Switzerland, USA

1.2 TERRESTRIAL ECOSYSTEMS

Meteorology & Atmospheric Sciences , Plant

Sciences , Geochemistry & Geophysics , Agriculture,

Soil Sciences

Roughly 70% of the tundra north of the Brooks

Range, Alaska, can be classified as moist nonacidic

(39%) and moist acidic tundra (31%). We investigated

the differences in energy partitioning and carbon balance

among these two important landscape types.

Despite structural differences in plant growth forms,

moss cover, and soil pH, the sensible and latent heat

fluxes were quite similar. However, aerodynamic properties

(i.e. roughness length), ground heat flux, and

CO2 flux were significantly different: aerodynamic

roughness of moist acidic tundra was 2.1 times higher

than, and ground heat flux was 36% lower than the

values obtained from moist nonacidic tundra. Daily

carbon balance showed 26% more net CO2 uptake

(with 34% greater ecosystem respiration and 30%

greater gross primary production) in moist acidic tundra.

The greater respiration rate in moist acidic tundra

was explained by differences in surface soil temperatures,

whereas the rate of gross primary production

was only half of what was expected from observed

differences in leaf area index. These differences suggest

that understanding the controls of CO2 exchange

in nonacidic moist tundra vegetation will be critical for

determining the carbon budget of the Low Arctic region.

Arctic Antarctic and Alpine Research, 2005, V37, N1,

FEB, pp 61-67

05.3-46

Survival and growth responses of Populus nigra,

Salix elaeagnos and Alnus incana cuttings to

varying levels of hydric stress

Francis R A, Gurnell A M, Petts G E, Edwards P J

England, Switzerland

Plant Sciences , Ecology , Geochemistry & Geophysics

, Agriculture, Soil Sciences , Hydrology

The Salicaceae and Betulaceae are important plant

families within riparian ecosystems throughout the

Northern hemisphere, and cuttings of species within

these families are often used in riparian restoration

projects due to their capacity for vegetative (asexual)

propagation and rapid growth. Riparian zones can experience

a wide range of hydrological conditions and

establishing cuttings may be subjected to substantially

varying levels of hydric stress from inundation and

drought. Tolerance to such stress can vary notably

between species, and the absence of knowledge of

species-specific responses to inundation and drought

has resulted in high mortality in many riparian restoration

projects. In this paper, the survival and growth responses

of Salix elaeagnos (Salicaceae), Populus nigra

(Salicaceae) and Alnus incana (Betulaceae) cuttings

in relation to varying rates of water table decline

and periods of inundation were investigated using rhizopods

during a 69-day greenhouse experiment, in

Global Change Abstracts – The Swiss Contribution 35


substrates of contrasting sediments (sand versus

gravel). Each species responded differently to the experimental

treatments. S. elaeagnos demonstrated an

ability to establish in stable, declining and inundated

conditions by the production of relatively substantial

root and shoot biomass in all treatments, along with

elongated roots when experiencing water table decline.

P. nigra showed high mortality and poor root

and shoot production in inundation treatments, suggesting

that this species is intolerant to reduced oxygen

conditions. A. incana displayed complete mortality

in all gravel- based treatments and high mortality or

poor growth in the sand-based inundation treatments.

All species showed preferences for stable conditions

without inundation, along with slow water table decline

for S. elaeagnos. Fast rates of water table decline

were detrimental to all species. Overall, sand

was a much more effective substrate than gravel for

supporting cutting establishment. These results suggest

that riparian restoration schemes utilizing S.

elaeagnos cuttings may experience greater success

than those using the other species investigated. P. nigra

cuttings may establish more easily if situated

where inundation does not occur often or for prolonged

periods, and A. incana cuttings should be

planted only; where very stable conditions dominate.

The study highlights the inter-species variability in the

survival and growth response of riparian trees to differing

hydrological conditions.

Forest Ecology and Management, 2005, V210, N1-3,

MAY 16, pp 291-301

05.3-47

Mycorrhizas improve nitrogen nutrition of

Trifolium repens after 8 yr of selection under

elevated atmospheric CO2 partial pressure

Gamper H, Hartwig U A, Leuchtmann A

Switzerland

Plant Sciences , Meteorology & Atmospheric

Sciences

Altered environmental conditions may change populations

of arbuscular mycorrhizal fungi and thereby affect

mycorrhizal functioning. We investigated whether

8 yr of free-air CO2 enrichment has selected fungi that

differently influence the nutrition and growth of host

plants. In a controlled pot experiment, two sets of seven

randomly picked single spore isolates, originating

from field plots of elevated (60 Pa) or ambient CO2

partial pressure (pCO(2)), were inoculated on nodulated

Trifolium repens (white clover) plants. Fungal isolates

belonged to the Glomus claroideum or Glomus

intraradices species complex, and host plants were

clonal micropropagates derived from nine genets. Total

nitrogen (N) concentration was increased in leaves

of plants inoculated with fungal isolates from elevated-pCO(2)

plots. These isolates took up nearly twice

36

Global Change Abstracts – The Swiss Contribution

1.2 TERRESTRIAL ECOSYSTEMS

as much N from the soil as isolates from ambientpCO(2)

plots and showed much greater stimulation of

biological N-2 fixation. The morpho-species identity of

isolates had a more pronounced effect on N-2 fixation

and on root length colonized than isolate identity. We

conclude that rising atmospheric pCO(2) may select

for fungal strains that will help their host plants to

meet increased N demands.

New Phytologist, 2005, V167, N2, AUG, pp 531-542

05.3-48

A test of the tree-line carbon limitation hypothesis

by in situ CO2 enrichment and defoliation

Handa I T, Körner C, Hättenschwiler S

Switzerland, France

Plant Sciences , Forestry , Meteorology &

Atmospheric Sciences , Ecology

Historically, carbon limitation, through a shortage of

photoassimilates has been argued to limit the growth

of trees at the upper altitudinal treeline. In a threeyear

free-air CO2 enrichment (FACE) experiment, two

species of 30-year-old alpine conifers (Larix decidua

and Pinus uncinata) were studied to test this hypothesis

in situ in the Swiss Central Alps (2180 m above

sea level). CO2 enrichment was combined with foliage

removal to test the effect of altered source-sink relationships

on tree growth and leaf level responses. Elevated

CO2 enhanced photosynthesis and increased

nonstructural carbohydrate (NSC) concentrations in

the needles of both species. While the deciduous

larch trees showed longer needles and a stimulation

of shoot growth over all three seasons when grown in

situ under elevated CO2, pine trees showed no such

responses. Irrespective of CO2 concentration, defoliation

in both species stimulated photosynthesis and increased

stomatal conductance in remaining currentyear

needles in the treatment year and reduced leaf

nitrogen concentration in the year following defoliation.

Defoliated larch trees had fewer and shorter needles

with reduced NSC concentrations in the year following

defoliation and showed no stimulation in shoot

elongation when exposed to elevated CO2. In contrast,

defoliation of evergreen pine trees had no effect

on needle NSC concentrations, but stimulated shoot

elongation when defoliated trees were exposed to elevated

CO2. After three years, our results suggest that

deciduous larch is carbon limited at treeline, while evergreen

pine is not. However, as indicated by the defoliation

treatment, the carbon economy of these trees

can clearly be modified by extreme events. The expected

changes in growth of these treeline trees with

improving carbon availability as atmospheric CO2 continues

to increase will thus depend on both the interplay

between biotic and abiotic processes, and the

species or tree functional types involved.

Ecology, 2005, V86, N5, MAY, pp 1288-1300


05.3-49

Effect of ecological compensation areas on

floristic and breeding bird diversity in Swiss

agricultural landscapes

Herzog F, Dreier S, Hofer G, Marfurt C, Schüpbach B,

Spiess M, Walter T

Switzerland

Ecology , Zoology , Biodiversity , Agriculture, Soil

Sciences

In the 1990s the Swiss agricultural policy was reformed

and new environmental objectives were formulated.

The aims of the reform were to halt the loss

of agro-biodiversity and to enable the spread of endangered

species. As a result, the utilised agricultural

area (UAA) is now interspersed with low input ecological

compensation areas (ECA), making up 13% of the

UAA (extensified grassland 90,000 ha, traditional orchards

25,000 ha, hedgerows 3000 ha, other elements

23,000 ha). To assess whether ECA contribute

to the enhancement of biodiversity, plant composition

was recorded on 1914 ECA of the Swiss plateau and

1966 territories of 27 bird species, which typically

breed in open and semi-open farmland, were mapped

and related to ECA. Eighty-six percent of ECA litter

meadows and 50% of ECA hedgerows were of good

ecological quality and attracted wetland and

hedgerow birds. Most ECA hay meadows and traditional

orchards, on the other hand, still reflected their

former intensive management with only 20 and 12%,

respectively, being of good ecological quality. Hardly

any benefits for grassland and orchard birds were observed.

Ecological quality of ECA was generally higher

in the bio-geographical region 'Basin of Lake Geneva

and Upper Rhine Valley' than in the other two regions

of the Swiss plateau and it was higher in the

agricultural production zone 'Prealpine Hills' than in

the 'Lowland Zone'.

Agriculture Ecosystems Environment, 2005, V108,

N3, JUN 30, pp 189-204

05.3-50

Predicting when animal populations are at risk

from roads: an interactive model of road

avoidance behavior

Jaeger J A G, Bowman J, Brennan J, Fahrig L, Bert D,

Bouchard J, Charbonneau N, Frank K, Gruber B,

von Toschanowitz K T

Switzerland, Canada, Germany

Zoology , Modelling , Ecology

Roads and traffic affect animal populations detrimentally

in four ways: they decrease habitat amount and

quality, enhance mortality due to collisions with vehicles,

prevent access to resources on the other side of

the road, and subdivide animal populations into smaller

and more vulnerable fractions. Roads will affect

persistence of animal populations differently depending

on (1) road avoidance behavior of the animals

1.2 TERRESTRIAL ECOSYSTEMS

(i.e., noise avoidance, road surface avoidance, and

car avoidance); (2) population sensitivity to the four

road effects; (3) road size; and (4) traffic volume. We

have created a model based on these population and

road characteristics to study the questions: (1) what

types of road avoidance behaviors make populations

more vulnerable to roads? ; (2) what types of roads

have the greatest impact on population persistence? ;

and (3) how much does the impact of roads vary with

the relative population sensitivity to the four road effects?

Our results suggest that, in general, the most

vulnerable populations are those with high noise and

high road surface avoidance, and secondly, those

with high noise avoidance only. Conversely, the least

vulnerable populations are those with high car avoidance

only, and secondly, high road surface and high

car avoidance. Populations with low overall road

avoidance and those with high overall road avoidance

tend to respond in opposite ways when the sensitivity

to the four road effects is varied. The same is true of

populations with high road surface avoidance when

compared to those with high car and high noise avoidance.

The model further predicted that traffic volume

has a larger effect than road size on the impact of

roads on population persistence. One potential application

of our model (to run the model on the web or to

download it go to www.glel.carieton.ca/ or

www.nls.ethz.ch/roadmodel/index.htm or contact the

first author) is to generate predictions for more structured

field studies of road avoidance behavior and its

influence on persistence of wildlife populations.

Ecological Modelling, 2005, V185, N2-4, JUL 10,

pp 329-348

05.3-51

The enemy release and EICA hypothesis revisited:

incorporating the fundamental difference between

specialist and generalist herbivores

Joshi J, Vrieling K

Switzerland, Netherlands

Plant Sciences , Zoology , Ecology , Biodiversity

The success of invasive plants has been attributed to

their escape from natural enemies and subsequent

evolutionary change in allocation from defence to

growth and reproduction. In common garden experiments

with Senecio jacobaea, a noxious invasive

weed almost worldwide, the invasive populations from

North America, Australia, and New Zealand did indeed

allocate more resources to vegetative and reproductive

biomass. However, invasive plants did not

show a complete change in allocation from defence to

growth and reproduction. Protection against generalist

herbivores increased in invasive populations and

pyrrolizidine alkaloids, their main anti-herbivore compounds,

did not decline in invasive populations but

were higher overall compared with native populations.

In contrast, invasive plants lost additional protection

against specialist herbivores adapted to pyrrolizidine

alkaloids. Hence, the absence of specialist herbivores

Global Change Abstracts – The Swiss Contribution 37


in invasive populations resulted in the evolution of

lower protection against specialists and increased

growth and reproduction, but also allowed a shift towards

higher protection against generalist herbivores.

Ecology Letters, 2005, V8, N7, JUL, pp 704-714

05.3-52

Modeling avian abundance from replicated counts

using binomial mixture models

Kery M, Royle J A, Schmid H

Switzerland, USA

Mapping , Modelling , Zoology , Biodiversity

Abundance estimation in ecology is usually accomplished

by capture- recapture, removal, or distance

sampling methods. These may be hard to implement

at large spatial scales. In contrast, binomial mixture

models enable abundance estimation without individual

identification, based simply on temporally and

spatially replicated counts. Here, we evaluate mixture

models using data from the national breeding bird

monitoring program in Switzerland, where some 250

1-km(2) quadrats are surveyed using the territory

mapping method three times during each breeding

season. We chose eight species with contrasting distribution

(wide-narrow), abundance (high-low), and

detectability (easy-difficult). Abundance was modeled

as a random effect with a Poisson or negative binomial

distribution, with mean affected by forest cover, elevation,

and route length. Detectability was a logit- linear

function of survey date, survey date-by-elevation,

and sampling effort (time per transect unit). Resulting

covariate effects and parameter estimates were consistent

with expectations. Detectability per territory

(for three surveys) ranged from 0.66 to 0.94 (mean

0.84) for easy species, and from 0.16 to 0.83 (mean

0.53) for difficult species, depended on survey effort

for two easy and all four difficult species, and

changed seasonally for three easy and three difficult

species. Abundance was positively related to route

length in three high-abundance and one low-abundance

(one easy and three difficult) species, and increased

with forest cover in five forest species, decreased

for two nonforest species, and was unaffected

for a generalist species. Abundance estimates under

the most parsimonious mixture models were between

1.1 and 8.9 (median 1.8) times greater than estimates

based on territory mapping; hence, three surveys

were insufficient to detect all territories for each

species. We conclude that binomial mixture models

are an important new approach for estimating abundance

corrected for detectability when only repeatedcount

data are available. Future developments envisioned

include estimation of trend, occupancy, and total

regional abundance.

Ecological Applications, 2005, V15, N4, AUG,

pp 1450-1461

38

Global Change Abstracts – The Swiss Contribution

1.2 TERRESTRIAL ECOSYSTEMS

05.3-53

Taking the fungal highway: Mobilization of

pollutant-degrading bacteria by fungi

Kohlmeier S, Smits T H M, Ford R M, Keel C,

Harms H, Wick L Y

Switzerland, USA, Germany

Microbiology , Modelling

The capacity of fungi to serve as vectors for the dispersion

of pollutant-degrading bacteria was analyzed

in laboratory model systems mimicking water-saturated

(agar surfaces) and unsaturated soil environments

(glass-bead-filled columns). Two common soil fungi

(Fusarium oxysporum and Rhexocercosporidium sp.)

forming hydrophilic and hydrophobic mycelia, respectively,

and three polycyclic aromatic hydrocarbon degrading

bacteria (Achromobacter sp. SKI, Mycobacterium

frederiksbergense LB501TG, and Sphingomonas

sp. L138) were selected based on the absence

of mutual antagonistic effects. It was shown

that fungal hyphae act as vectors for bacterial transport

with mobilization strongly depending on the specific

microorganisms chosen: The motile strain Achromobacter

sp. SKI was most efficiently spread along

hyphae of hydrophilic F oxysporum in both model systems

with transport velocities of up to 1 cm d(-1),

whereas no dispersion of the two nonmotile strains

was observed in the presence of F oxysporum. By

contrast, none of the bacteria was mobilized along the

hydrophobic mycelia of Rhexocercosporidium sp.

growing on agar surfaces. In column experiments

however, strain SKI was mobilized by Rhexocercosporidium

sp. It is hypothesized that bacteria may

move by their intrinsic motility through continuous

(physiological) liquid films forming around fungal hyphae.

The results of this study suggest that the specific

stimulation of indigenous fungi may be a strategy to

mobilize pollutant-degrading bacteria leading to their

homogenization in polluted soil thereby improving

bioremediation.

Environmental Science Technology, 2005, V39, N12,

JUN 15, pp 4640-4646

05.3-54

Relative importance of resource quantity, isolation

and habitat quality for landscape distribution of a

monophagous butterfly

Krauss J, Steffan Dewenter I, Müller C B, Tscharntke T

Germany, Switzerland

Zoology , Biodiversity , Agriculture, Soil Sciences

Fragmentation of food resources is a major cause of

species extinction. We tested the effects of habitat

area, isolation and quality for the occurrence and population

density of the endangered butterfly Polyommatus

coridon. Polyommatus coridon larvae are


monophagous on the plant Hippocrepis comosa, and

both species are specialised on calcareous grassland,

which is an endangered and highly fragmented habitat

type in Germany. In 2001 we surveyed all known

calcareous grasslands (n=298) around the city of Gottingen

(Germany) to map the population size of H. comosa

in these habitats. Further, habitat isolation (between-patch

distance: 70-7220 m) and habitat quality

(cover of flowering plants, height of herb layer, percent

bare ground, cover of shrub layer, wind protection,

inclination) were quantified. Hippocrepis comosa

occurred on only 124 fragments, which were then surveyed

by 20 min transect counts for adult P. coridon in

2001 and 2002. Occurrence and population density of

P. coridon were largely determined by the population

size of its larval food plant, which was correlated with

grassland area. Effects of habitat isolation and habitat

quality on P. coridon populations contributed only little

to the explanation. In conclusion, this monophagous

habitat specialist depended on large habitats with

large food plant populations to exist in viable populations.

Habitat isolation and quality appear to contribute

to occurrence and density patterns only in

landscapes where these factors shift towards extremes,

therefore general recommendations for conservation

programs are difficult as they depend on regional

distinctions.

Ecography, 2005, V28, N4, AUG, pp 465-474

05.3-55

Effect of microsites, logs and ungulate browsing

on Picea abies regeneration in a mountain forest

(vol 205, pg 251, 2005)

Kupferschmid A D, Bugmann H

Switzerland

Forestry , Plant Sciences

Forest Ecology and Management, 2005, V210, N1-3,

MAY 16, p 477

05.3-56

Responses of deciduous forest trees to severe

drought in Central Europe

Leuzinger S, Zotz G, Asshoff R, Körner C

Switzerland

Forestry , Plant Sciences , Hydrology

In 2003, Central Europe experienced the warmest

summer on record combined with unusually low precipitation.

We studied plant water relations and phenology

in a 100-year-old mixed deciduous forest on a

slope (no ground water table) near Basel using the

Swiss Canopy Crane (SCC). The drought lasted from

early June to mid September. We studied five deciduous

tree species; half of the individuals were exposed

to elevated CO2 concentration ((CO2)) (530 ppm) using

a free- air, atmospheric CO2-enrichment system.

1.2 TERRESTRIAL ECOSYSTEMS

In late July, after the first eight weeks of drought,

mean predawn leaf water potential about 30 m above

ground was -0.9 MPa across all trees, dropping to a

mean of -1.5 MPa in mid-August when the top 1 m of

the soil profile had no plant accessible moisture.

Mean stomatal conductance and rates of maximum

net photosynthesis decreased considerably in mid-

August across all species. However, daily peak values

of sap flow remained surprisingly constant over the

whole period in Quercus petraea (Matt.) Liebl., and

decreased to only about half of the early summer

maxima in Fagus sylvatica L. and Carpinus betulus L.

(stomatal down- regulation of flux). Although we detected

no differences in most parameters between

CO2-treated and control trees, predawn leaf water potential

tended to be less negative in trees exposed to

elevated (CO2). Leaf longevity was greater in 2003

compared with the previous years, but the seasonal

increase in stem basal area reached only about 75%

of that in previous years. Our data suggest that the investigated

tree species, particularly Q. petraea, did

not experience severe water stress. However, an increased

frequency of such exceptionally dry summers

may have a more serious impact than a single event

and would give Q. petraea a competitive advantage in

the long run.

Tree Physiology, 2005, V25, N6, JUN, pp 641-650

05.3-57

Year-round measurements of net ecosystem CO2

flux over a montane larch forest in Mongolia

Li S G, Asanuma J, Kotani A, Eugster W, Davaa G,

Oyunbaatar D, Sugita M

Japan, Switzerland, Mongol Peo Rep

Ecology , Forestry , Plant Sciences , Meteorology &

Atmospheric Sciences

Mongolian boreal forest merits special attention since

it is located in the transitional area between the southern

Siberian boreal forest and the Asian steppe zone,

a vulnerable region being potentially affected by global

warming and anthropogenic activities. This paper

presents the first full-year-long continuous measurements

of net ecosystem CO2 flux (NEE) made over a

montane larch (Larix sibirica Ledeb.) forest in Mongolia

from 25 March 2003 to 24 March 2004 (366 days)

using the eddy covariance technique. The hourly

maximum uptake was -10.1 μ mol m(-2) s(-1). The

maximum daily uptake of -4.0 g C m(-2) d(-1) (negative

NEE values denote net carbon uptake by the

canopy from the atmosphere) occurred in July. The

annual cumulative NEE was -85 g C m(-2), indicating

that the forest acted as a net sink of CO2. We examined

the responses of NEE to environmental conditions

in the growing season from May to September.

Both daytime 30-min mean and daily integrated NEE

responded to incident photosynthetically active radiation

(PAR) in a rectangular hyperbolic fashion. Model

results show that the apparent quantum yield (&alpha)

Global Change Abstracts – The Swiss Contribution 39


was -0.0133 &PLUSMN; 0.0011 mmol CO2 per μ

mol of photons, and the bulk light use efficiency (LUE)

on the daily basis was -6.7 mmol CO2 per mole of

PAR photons over the entire growing season for this

forest. Additionally, daily integrated NEE was also a

linear function of the normalized difference vegetation

index (NDVI), a linear function of mean daily air temperature

(T-a), and a quadratic polynomial function of

daily means of the atmospheric water vapor pressure

deficit (VPD). Among these factors, LAI (as measured

by NDVI) was dominant in affecting the dynamics of

NEE, followed by T-a. Lower T-a was limiting the

growth rate of this montane larch forest. As daily

means of VPD exceeded 1.2 kPa, net CO2 uptake by

the canopy declined. Nevertheless, water stress was

not observed as a problem for the forest growth.

Journal of Geophysical Research Atmospheres, 2005,

V110, ND9, MAY 3, ARTN: D09303

05.3-58

Influence of myristic acid supplementation on

energy, fatty acid and calcium metabolism of

sheep as affected by dietary calcium and forage :

concentrate ratio

Machmüller A, Kreuzer M

Switzerland

Agriculture, Soil Sciences , Zoology

In a 6 x 6 Latin square arrangement, sheep of 41 kg

body weight were fed myristic acid (C14:0; 50 g/kg

dry matter (DM)) supplemented to two basal diets of

forage : concentrate ratios of 1 : 1.5 and 1 : 0.5 and

adjusted to dietary calcium (Ca) contents of either 4.2

or 9.0 g /kg DM (the latter only together with C14:0

supplementation). Various variables of energy, fatty

acid and Ca metabolism were determined in combined

digestibility and respiratory chamber measurements.

With C14:0 addition the energy loss via the

faeces increased (p < 0.05, post hoc test) without affecting

energy digestibility of the complete diet. The

apparent digestibility of supplemented C14:0 was

higher (p < 0.01) with approximately 0.8 in the foragebased

diet than in the concentrate-based diet (approximately

0.6). The elevated levels of plasma C14:0

were mainly accompanied by reduced C18:0 and

C18:1 levels. The estimated apparent content of metabolizable

energy (ME) of added C14:0 was either

24.5 MJ/kg (concentrate-based diet) or 32.1 MJ/kg

(forage-based diet). Extra Ca equalized these differences

between basal diets and ME contents amounted

to 33.0 MJ/kg on average. As expected from corresponding

slight shifts in energy metabolizability, the

total efficiency of ME utilization increased (p < 0.1)

with C14:0. The lower level of dietary Ca was still

within the range recommended, but adding C14:0 to

the concentrate-based diet reduced Ca retention in

the body of the sheep from 0.9 to -0.1 g/day because

of an impaired (p < 0.05, post hoc test) net Ca absorption,

whereas no effect was found with the forage-based

diet. With C14:0 addition, plasma total

40

1.2 TERRESTRIAL ECOSYSTEMS

Global Change Abstracts – The Swiss Contribution

phosphorus (P) and serum calcitrol levels increased

(p < 0.05, post hoc test) while Ca concentrations did

not clearly reflect the reduced net Ca absorption. Increasing

the dietary Ca content prevented adverse effects

on Ca retention in the concentrate-based diet

and improved Ca retention in the forage-based diet. In

conclusion, the C14:0 supplementation reduced Ca

availability in concentrate-based diets while an additional

supply of Ca improved Ca and energy retention.

Consequently, Ca supply should exceed recommended

levels in diet types where dietary lipids are likely to

reduce Ca availability and a compromise in basal diet

type has to found to be able to profit best from the energetic

value and the methane-suppressing properties

of C14:0.

Journal of Animal Physiology and Animal Nutrition,

2005, V89, N7-8, AUG, pp 284-296

05.3-59

Forest storm damage is more frequent on acidic

soils

Mayer P, Brang P, Dobbertin M, Hallenbarter D,

Renaud J P, Walthert L, Zimmermann S

Switzerland, Austria, France

Plant Sciences , Forestry , Agriculture, Soil Sciences

We assessed the effect of chemical soil properties

and acidifying depositions ( sulphur and nitrogen) on

the occurrence of storm damage during the storms

"Lothar" and "Martin" ( December 1999). Data from

969 sites in France, southern Germany and Switzerland

was analysed with multiple logistic regression

models. Variables found to be significantly related to

storm damage, which was mainly scattered damage

in our study, were "country", "soil pH", "proportion of

coniferous trees", "slope", "humus type", "stand

height", and "altitude". Wind speed was not significantly

related to storm damage in the global model,

but only in the model for France. Soil pH was one of

the most significant factors with a lower pH on damaged

plots. Atmospheric deposition rates were significantly

associated with soil pH, but not directly with

storm damage. Even though the mechanisms involved

in the relationship between soil acidity and

storm damage are still poorly understood, soil acidity

should be considered a significant risk factor. Moreover,

this large-scale study confirms that increasing

the proportion of deciduous trees would reduce the

susceptibility of forests to storm damage.

Annals of Forest Science, 2005, V62, N4, JUN,

pp 303-311

05.3-60

An experimental test of the evolution of increased

competitive ability hypothesis in goldenrod,

Solidago gigantea

Meyer G, Clare R, Weber E


USA, Switzerland

Plant Sciences , Zoology , Biodiversity

The mechanisms that allow introduced plants to become

invasive are poorly understood. Here, we present

a test of the evolution of increased competitive

ability hypothesis, which holds that because specialized

natural enemies may be absent from the introduced

range, exotic plants may evolve to invest less

in anti-herbivore defenses and thereby gain a competitive

advantage over native plants. We grew Solidago

gigantea plants derived from both the native range

(North America) and the invasive range (Europe) in a

common garden in the native range for 2 years. Half

the plants were treated with insecticide to protect

them from insect herbivores and the other half were

exposed to insects that colonized the garden from

nearby fields. Insect herbivore biomass was significantly

higher on European plants than US plants in

the first year but not the second. European plants

were more heavily attacked by pathogens in both

years of the study. When exposed to insect herbivores,

US plants produced more seed than European

plants, but when plants were protected from herbivores,

seed production was equivalent between US

plants and European plants. The presence of insect

herbivores suppressed seed production of European

plants much more than that of US plants, even though

the level of herbivory experienced by European and

US plants was similar in the second year, suggesting

that the ability to tolerate herbivory was diminished in

European plants. These results partially support the

EICA hypothesis: plants from the introduced range

were more susceptible to some natural enemies and

benefited more from insect removal than plants from

the native range. The prediction that European plants

would perform better than US plants in the absence of

insect herbivores was not supported.

Oecologia, 2005, V144, N2, JUN, pp 299-307

05.3-61

Ectomycorrhizas and mast fruiting in trees:

linked by climate-driven tree resources?

Newbery D M

Switzerland

Plant Sciences , Meteorology & Atmospheric

Sciences , Forestry

New Phytologist, 2005, V167, N2, AUG, pp 324-326

05.3-62

Seasonal trends in reduced leaf gas exchange

and ozone-induced foliar injury in three ozone

sensitive woody plant species

Novak K, Schaub M, Fuhrer J, Skelly J M, Hug C,

Landolt W, Bleuler P, Kräuchi N

Switzerland, USA

1.2 TERRESTRIAL ECOSYSTEMS

Plant Sciences , Meteorology & Atmospheric

Sciences , Forestry

Seasonal trends in leaf gas exchange and ozone-induced

visible foliar injury were investigated for three

ozone sensitive woody plant species. Seedlings of

Populus nigra L., Viburnum lantana L., and Fraxinus

excelsior L. were grown in charcoal-filtered chambers,

non- filtered chambers and open plots. Injury assessments

and leaf gas exchange measurements were

conducted from June to October during 2002. All

species developed typical ozone-induced foliar injury.

For plants exposed to non-filtered air as compared to

the charcoal- filtered air, mean net photosynthesis

was reduced by 25%, 21%, and 18% and mean stomatal

conductance was reduced by 25%, 16%, and 8%

for P. nigra, V. lantana, and F. excelsior, respectively.

The timing and severity of the reductions in leaf gas

exchange were species specific and corresponded to

the onset of visible foliar injury.

Environmental Pollution, 2005, V136, N1, JUL,

pp 33-45

05.3-63

Glomus badium, a new sporocarpic mycorrhizal

fungal species from European grasslands with

higher soil pH

Oehl F, Redecker D, Sieverding E

Germany, Switzerland

Plant Sciences , Agriculture, Soil Sciences ,

Geochemistry & Geophysics , Microbiology

Glomus badium forms small sporocarps with about

180-280 µm in diameter. The sporocarps have no

peridum and contain 5-30 spores. The spores are situated

around and partly within a whitish to yellowish

gleba of interwoven intrasporocarpic hyphae. Spores

are reddish brown to dark brown to black, globose,

subglobose to ovoid, 5190 x 75-120 µm in diameter.

Spores have three wall layers, in total (5.5-)7-14 µm

thick. The innermost layer usually closes the pore at

the spore base together with a bridging septum

formed by the middle layer. The subtending hypha of

each spore is usually very short (< 1-2.5 µm) and,

thus, the spore base is difficult to observe. The new

species can easily be differentiated from other sporocarp-forming

Glomus spp. by the structure and the

size of the sporocarps and spores, the organisation of

the spores in the sporocarps, the colour of the spore

walls and in particular through the characteristics of

the intrasporocarpic hyphae and the short subtending

hypha at the spore base. A partial DNA sequence of

the 18S ribosomal small subunit gene of spores of G.

badium was determined. Phylogenetic analyses firmly

placed the sequence into Glomus spp. of group A of

the Glomeraceae, with no close matches among

named sequences obtained from spores of other Glomus

species. Several sequences from field collected

roots infected with AMF showed a high similarity to G.

badium. Glomus badium is a frequent member of the

Global Change Abstracts – The Swiss Contribution 41


arbuscular mycorrhizal fungi community of grasslands,

grass-intercropped vineyards or olive fields, or

no-till arable lands in Germany, France, Switzerland

and Italy. It has been found in grasslands LIP to the

tree line in the Alps, but so far, only in soils with pH 6-8.

Journal of Applied Botany and Food Quality,

Angewandte Botanik, 2005, V79, N1, APR, pp 38-43

05.3-64

Carbon dioxide regime, species identity and

influence of species initial abundance as determinants

of change in stand biomass composition in

five-species communities: an investigation using

a simplex design and RGRD analysis

Ramseier D, Connolly J, Bazzaz F A

Switzerland, USA

Ecology , Plant Sciences

1 The effect of elevated CO2 on species' performance

was investigated in communities composed of five

annual weeds that are characteristic of early old field

succession in central Europe: Centaurea cyanus L.,

Matricaria chamomilla L., Silene noctiflora L., Papaver

rhoeas L. and Legousia speculum-veneris (L.)

Chaix. 2 The experiment was based on a simplex design,

repeated at two overall levels of initial stand

density, to give a wide range of five-species communities

across which the initial composition and

species abundance varied systematically. 3 A multivariate

method, based on analysing the differences in

relative growth rates (RGRD) between pairs of

species, was extended for use with more than two

species, in order to assess the relative importance of

various determinants of change in stand biomass

composition. 4 On average, Centaurea (54.6% of final

yield) gave the highest yield, followed by Matricaria

(22.9%), Silene (16.9%), Legousia (3.1%) and

Papaver (2.7%). 5 The major determinants of change

in community structure were species identity and CO2

level. Elevated CO2 significantly changed community

composition towards the previously more poorly performing

species Silene, Legousia and Papaver. 6 Despite

strong effects of intra- and interspecific competition

on individual species performance, species' initial

abundance had relatively little impact on the change

in community composition. Most cases where such

effects were significant involved Silene: performance

of Papaver was poorer in communities with higher

initial presence of Silene and higher initial abundances

of Centaurea and Matricaria always facilitated

performance of Silene. 7 These new methods

proved a powerful system for identifying the biotic

and abiotic factors determining change in biomass

composition in multispecies communities.

Journal of Ecology, 2005, V93, N3, JUN, pp 502-511

42

1.2 TERRESTRIAL ECOSYSTEMS

Global Change Abstracts – The Swiss Contribution

05.3-65

Recent climate change: Rethinking drought in the

context of Forest Fire Research in Ticino, South of

Switzerland

Reinhard M, Rebetez M, Schlaepfer R

Switzerland

Forestry , Meteorology & Atmospheric Sciences

We analyse trends over the past 32 years in drought

variables in the context of forest fire research and climate

change in Ticino, Southern Switzerland. January

to April and in particular the month of March have become

drier. This is the time of the year when forest

fires are most frequent. Our results show an increasing

trend in all climatic variables favourable to drought

and forest fires, including the length of episodes without

precipitation, sunshine duration and temperature,

and a decrease in relative humidity. The only exception

is the number of "foehn" days, which have not

significantly increased.

Theoretical and Applied Climatology, 2005, V82,

N1-2, AUG, pp 17-25

05.3-66

CO2 emissions from red wood ant (Formica rufa

group) mounds: Seasonal and diurnal patterns

related to air temperature

Risch A C, Schutz M, Jurgensen M F, Domisch T,

Ohashi M, Finer L

Switzerland, USA, Finland

Geochemistry & Geophysics , Meteorology &

Atmospheric Sciences , Zoology

Red wood ant (Formica rufa group) mounds release

high amounts of carbon dioxide (CO2). As red wood

ants and other invertebrates living in mounds are poikilothermal

organisms, their metabolism and therefore

CO2 emissions are affected by changes in temperature.

Thus, seasonal or diurnal changes in air temperature

could affect CO2 emissions from mounds. We found

that seasonal mound CO2 emissions and air temperature

were correlated, both peaking in mid-summer. In

contrast, diurnal CO2 emissions and air temperature

were inversely correlated, as we observed highest C

fluxes during the night when air temperature was lowest.

This CO2 emission pattern can likely be explained

by higher metabolic rates of ants resulting from their

clustering, and increased numbers of ants in the

mound when outside air temperature drops at night.

Changes in microbial decomposition of mound organic

matter or thermal convection of warm CO2-rich mound

air to the colder surface at night likely do not play a major

role in the diurnal C fluxes observed in our study.

Annales Zoologici Fennici, 2005, V42, N3, JUN 28,

pp 283-290


05.3-67

Effect of land management on ecosystem carbon

fluxes at a subalpine grassland site in the Swiss

Alps

Rogiers N, Eugster W, Furger M, Siegwolf R

Switzerland

Ecology , Agriculture, Soil Sciences , Plant Sciences ,

Meteorology & Atmospheric Sciences

The influence of agricultural management on the CO,

budget of a typical subalpine grassland was investigated

at the Swiss CARBOMONT site at Rigi-Seebodenalp

(1025 m a.s.l.) in Central Switzerland. Eddy

covariance flux measurements obtained during the

first growing season from the mid of spring until the

first snow fall (17 Mai to 25 September 2002) are reported.

With respect to the 10-year average 1992-

2001. we found that this growing season had started

10 days earlier than normal, but was close to average

temperature with above- normal precipitation (100-

255% depending on month). Using a footprint model

we found that a simple approach using wind direction

sectors was adequate to classify our CO2 fluxes as

being controlled by either meadow or pasture. Two

significantly different light response curves could be

determined: one for periods with external interventions

(grass cutting, cattle grazing) and the other for

periods without external interventions. Other than this,

meadow and pasture were similar, with a net carbon

gain of - 128 +/- 17 Cm-2 on the undisturbed meadow,

and a net carbon loss of 79 17 C m(-2) on the managed

meadow, and 270 +/- 24 g C m(-2) on the pasture

during 131 days of the growing season. respectively.

The grass cut in June reduced the CO, uptake

of the meadow by 50 +/- 2% until regrowth of the vegetation.

Cattle grazing reduced gross uptake over the

whole vegetation period (37 2%), but left respiration at

a similar level as observed in the meadow.

Theoretical and Applied Climatology, 2005, V80,

N2-4, APR, pp 187-203

05.3-68

Habitat and plant specificity of Trichogramma egg

parasitoids - underlying mechanisms and

implications

Romeis A, Babendreier D, Wackers F L, Shanower T G

Switzerland, Netherlands, USA

Plant Sciences , Zoology , Agriculture, Soil Sciences

Egg parasitoids of the genus Trichogramma are

among the most important and best-studied natural

enemies worldwide. Parasitism levels by Trichogramma

vary greatly among different habitats, plants or

plant structures on which the host eggs are located.

Here we summarise the published evidence on mechanisms

that may underlie the observed variation in

parasitism rates. These mechanisms include plant

spacing, plant structure, plant surface structure and

1.2 TERRESTRIAL ECOSYSTEMS

chemistry, plant volatiles and plant colour. In addition,

plants can affect parasitoid behaviour and activity by

providing carbohydrate food sources such as nectar

to the adult wasps, and by affecting the nutritional

quality of the host eggs for progeny development.

Knowledge of plant and habitat factors that affect Trichogramma

spp. efficacy has important implications

for biological. control, and for assessing the risks that

mass-released Trichogramma spp. may pose to nontarget

insects.

Basic and Applied Ecology, 2005, V6, N3, pp 215-236

05.3-69

Reducing vulnerability of agriculture and forestry

to climate variability and change: Workshop

summary and recommendations

Salinger M J, Sivakumar M V K, Motha R

New Zealand, Switzerland, USA

Agriculture, Soil Sciences , Forestry , Meteorology &

Atmospheric Sciences , Hydrology , Social Sciences

The International Workshop on Reducing Vulnerability

of Agriculture and Forestry to Climate Variability and

Climate Change held in Ljubljana, Solvenia, from 7 to

9 October 2002 addressed a range of important issues

relating to climate variability, climate change,

agriculture, and forestry including the state of agriculture

and forestry and agrometeological information,

and potential adaptation strategies for agriculture and

forestry to changing climate conditions and other

pressures. There is evidence that global warming

over the last millennium has already resulted in increased

global average annual temperature and

changes in rainfall, with the 1990s being likely the

warmest decade in the Northern Hemisphere at least.

During the past century, changes in temperature patterns

have, for example, had a direct impact on the

number of frost days and the length of growing seasons

with significant implications for agriculture and

forestry. Land cover changes, changes in global

ocean circulation and sea surface temperature patterns,

and changes in the composition of the global

atmosphere are leading to changes in rainfall. These

changes may be more pronounced in the tropics. For

example, crop varieties grown in the Sahel may not

be able to withstand the projected warming trends

and will certainly be at risk due to projected lower

amounts of rainfall as well. Seasonal to interannual

climate forecasts will definitely improve in the future

with a better understanding of dynamic relationships.

However, the main issue at present is how to make

better use of the existing information and dispersion

of knowledge to the farm level. Direct participation by

the farming communities in pilot projects on agrometeorological

services will be essential to determine the

actual value of forecasts and to better identify the

specific user needs. Old (visits, extension radio) and

new (internet) communication techniques, when

adapted to local applications, may assist in the dis-

Global Change Abstracts – The Swiss Contribution 43


semination of useful information to the farmers and

decision makers. Some farming systems with an inherent

resilience may adapt more readily to climate

pressures, making long-term adjustments to varying

and changing conditions. Other systems will need interventions

for adaptation that should be more strongly

supported by agrometeorological services for agricultural

producers. This applies, among others, to

systems where pests and diseases play an important

role. Scientists have to guide policy makers in fostering

an environment in which adaptation strategies can

be effected. There is a clear need for integrating preparedness

for climate variability and climate change.

In developed countries, a trend of higher yields, but

with greater annual fluctuations and changes in cropping

patterns and crop calendars can be expected

with changing climate scenarios. Shifts in projected

cropping patterns can be disruptive to rural societies

in general. However, developed countries have the

technology to adapt more readily to the projected climate

changes. In many developing countries, the present

conditions of agriculture and forestry are already

marginal, due to degradation of natural resources, the

use of inappropriate technologies and other stresses.

For these reasons, the ability to adapt will be more

difficult in the tropics and subtropics and in countries

in transition. Food security will remain a problem in

many developing countries. Nevertheless, there are

many examples of traditional knowledge, indigenous

technologies and local innovations that can be used

effectively as a foundation for improved frming systems.

Before developing adaptation strategies, it is

essential to learn from the actual difficulties faced by

farmers to cope with risk management at the farm level.

Agrometeorologists must play an important role in

assisting farmers with the development of feasible

strategies to adapt to climate variability and climate

change. Agrometeorologists should also advise national

policy makers on the urgent need to cope with

the vulnerabilities of agriculture and forestry to climate

variability and climate change. The workshop recommendations

were largely limited to adaptation. Adaptation

to the adverse effects of climate variability and

climate change is of high priority for nearly all countries,

but developing countries are particularly vulnerable.

Effective measures to cope with vulnerability

and adaptation need to be developed at all levels. Capacity

building must be integrated into adaptation

measures for sustainable agricultural development

strategies. Consequently, nations must develop

strategies that effectively focus on specific regional issues

to promote sustainable development.

Climatic Change, 2005, V70, N1-2, MAY, pp 341-362

05.3-70

Impacts of present and future climate variability

and change on agriculture and forestry in the arid

and semi-arid tropics

Sivakumar M V K, Das H P, Brunini O

Switzerland, India, Brazil

44

1.2 TERRESTRIAL ECOSYSTEMS

Global Change Abstracts – The Swiss Contribution

Meteorology & Atmospheric Sciences , Agriculture,

Soil Sciences , Forestry , Modelling

The arid and semi-arid regions account for approximately

30% of the world total area and are inhabited

by approximately 20% of the total world population.

Issues of present and future climate variability and

change on agriculture and forestry in the arid and

semi-arid tropics of the world were examined and discussion

under each of these issues had been presented

separately for Asia, Africa and Latin America.

Several countries in tropical Asia have reported increasing

surface temperature trends in recent decades.

Although, there is no definite trend discernible

in the long-term mean for precipitation for the tropical

Asian region, many countries have shown a decreasing

trend in rainfall in the past three decades. African

rainfall has changed substantially over the last 60 yr

and a number of theoretical, modelling and empirical

analyses have suggested that noticeable changes in

the frequency and intensity of extreme events, including

floods may occur when there are only small

changes in climate. Climate in Latin America is affected

by the El Ni (n) over tildeo- southern oscillation

(ENSO) phases and there is a close relationship between

the increase and decrease of rainfall depending

upon the warm or cold phases of the phenomenon.

Over land regions of Asia, the projected

area-averaged annual mean warming is likely to be

1.6 +/- 0.2 degrees C in the 2020s, 3.1 +/- 0.3 degrees

C in the 2050s, and 4.6 +/- 0.4 degrees C in the

2080s and the models show high uncertainty in projections

of future winter and summer precipitation. Future

annual warming across Africa is projected to

range from 0.2 degrees C per decade to more than

0.5 degrees C per decade, while future changes in

mean seasonal rainfall in Africa are less well defined.

In Latin America, projections indicate a slight increase

in temperature and changes in precipitation. Impacts

of climate variability and changes are discussed with

suitable examples. Agricultural productivity in tropical

Asia is sensitive not only to temperature increases,

but also to changes in the nature and characteristics

of monsoon. Simulations of the impacts of climate

change using crop simulation models show that crop

yield decreases due to climate change could have serious

impacts on food security in tropical Asia. Climate

change is likely to cause environmental and social

stress in many of Asia's rangelands and drylands. In

the arid and semi-arid tropics of Africa, which are already

having difficulty coping with environmental

stress, climate change resulting in increased frequencies

of drought poses the greatest risk to agriculture.

Impacts were described as those related to projected

temperature increases, the possible consequences to

water balance of the combination of enhanced temperatures

and changes in precipitation and sensitivity

of different crops/cropping systems to projected

changes. In Latin America, agriculture and water resources

are most affected through the impact of extreme

temperatures (excessive heat, frost) and the

changes in rainfall (droughts, flooding). Adaptation potential

in the arid and semi-arid tropics of Asia, Africa


and Latin America was described using suitable examples.

It is emphasized that approaches need to be

prescriptive and dynamic, rather than descriptive and

static.

Climatic Change, 2005, V70, N1-2, MAY, pp 31-72

05.3-71

Safe sites for tree regeneration in wooded

pastures: A case of associational resistance

Smit C, Beguin D, Buttler A, Müller Schärer H

Switzerland, France

Forestry , Plant Sciences , Ecology

Question: Are tree saplings in wooded pastures spatially

associated with specific nurse structures or

plants that facilitate tree sapling survival? Location:

Wooded pastures in the Jura Mountains, Switzerland.

Methods: In two sites, 73 kin apart, we sampled 294

plots of 4 m(2), systematically distributed on I ha. We

recorded number and height of all established Picea

abies saplings (> I a of age and up to 40 cm in

height), and visually estimatec cover of rocks, shrubs,

tree stumps, overhanging tree branches and unpalatable

plant species. Results: Despite differences in site

characteristics, we found overall positive effects of

cover of unpalatable plants, rocky outcrops and tree

stumps on the density of Picea saplings. Plots with

tree stumps and higher cover of rocky outcrops and

unpalatable plants were more likely to contain Picea

saplings. Conclusions: Unpalatable plants, rocky outcrops

and tree stumps seem to form safe sites for

Picea saplings in this grazed system, improving their

establishment and survival. Our findings support the

idea that associational resistance drives the dynamics

of wooded pastures, but experimental evidence for

this hypothesis is still required.

Journal of Vegetation Science, 2005, V16, N2, APR,

pp 209-214

05.3-72

The impact of windthrow on carbon sequestration

in Switzerland: a model-based assessment

Thurig E, Palosuo T, Bucher J, Kaufmann E

Switzerland, Finland

Agriculture, Soil Sciences , Modelling , Forestry ,

Geochemistry & Geophysics , Plant Sciences

Carbon sequestered in biomass is not necessarily

stored infinitely, but is exposed to human or natural

disturbances. Storm is the most important natural disturbance

agent in Swiss forests. Therefore, if forests

are taken into account in the national carbon budget,

the impact of windthrow on carbon pools and fluxes

should be included. In this article the forest scenario

model MASSIMO and the soil carbon model YASSO

were applied to assess the effect of forest management

and an increased storm activity on the carbon

sequestration in Swiss forests. First, the soil model

1.2 TERRESTRIAL ECOSYSTEMS

was adapted to Swiss conditions and validated. Second,

carbon fluxes were assessed applying the two

models under various forest management scenarios

and storm frequencies. In particular, the influence of

clearing after a storm event on the carbon budget was

analyzed. The evaluation of the model results showed

that the soil model reliably reproduces the amount of

soil carbon at the test sites. The simulation results indicated

that, within the simulated time period of 40

years, forest management has a strong influence on

the carbon budget. However, forest soils only react

slightly to changes in the above-ground biomass. The

results also showed that a storm frequency increase

of 30% has a small impact on the national carbon

budget of forests. To develop effective mitigation

strategies for forest management, however, longer

time periods must be regarded.

Forest Ecology and Management, 2005, V210, N1-3,

MAY 16, pp 337-350

05.3-73

The effect of nitrogen fertilization on fungistatic

phenolic compounds in roots of beech (Fagus

sylvatica) and Norway spruce (Picea abies)

Tomova L, Braun S, Flückiger W

Switzerland

Geochemistry & Geophysics , Plant Sciences ,

Agriculture, Soil Sciences , Forestry

The effect of nitrogen fertilization on fungistatic phenolic

compounds in fine roots of beech and Norway

spruce growing in afforestation plots was analysed.

The plots were situated at two sites in Switzerland on

acidic soil with low base saturation. For 9 years, the

trees have been treated with dry ammonium nitrate to

give 0, 10, 20, 40, 80, 160 kg N ha(-1) year(-1), respectively.

The phenolic compounds responded differently

to fertilization. Fine roots of beech showed a significant

decrease of (-)-epicatechin and piceatannol

with increasing nitrogen fertilization. The concentration

of protocatechuic acid was increased with fertilization.

Roots of fertilized Norway spruce showed significantly

decreased concentrations of 4-hydroxyacetophenone

and piceatannol. The mycelial growth of

three isolates each of Heterobasidion annosum s.l.

and Cylindrocarpon destructans was tested on agar

media containing various phenolic compounds in concentrations

found in fine roots of Norway spruce

(Picea abies) and beech (Fagus sylvatica). All three

H. annosum isolates were inhibited by p-coumaric

acid and (-)- epicatechin. Two isolates were inhibited

by another four phenolic compounds (p-hydroxybenzoic

acid, 4-hydroxyacetophenone, piceatannol and

protocatechuic acid), one by (+)-catechin. Two of

three C. destructans isolates were inhibited by all

phenolic compounds except for (+)-catechin which affected

only one isolate, one isolate did not respond at

all.

Forest Pathology, 2005, V35, N4, AUG, pp 262-276

Global Change Abstracts – The Swiss Contribution 45


05.3-74

Local and landscape influence on amphibian

occurrence and abundance

van Buskirk J

Switzerland

Zoology , Ecology , Marine & Freshwater Biology ,

Agriculture, Soil Sciences , Biodiversity

The traditional emphasis in ecology on local species

interactions has recently broadened to include landscape-level

processes. I used data from a seven-year

survey of ponds in northern Switzerland to judge the

relative contributions of local and landscape influences

to the occurrence and density of larvae of eight

amphibian species. Each pond was sampled twice

each year using pipe samples and dip nets. Analyses

evaluated support for a series of alternative models,

some suggested by current ideas in aquatic ecology

and others designed to reveal the impact of key variables.

Results strongly supported models that include

both local and landscape covariates. Species differed

in preference for permanent or temporary ponds,

high- or low-predator ponds, and landscapes within

forested or open areas. The occurrence of all species

was positively correlated with the densities of other

species, suggesting that competition was less important

than variation in quality among sites. The results

emphasize the importance of local processes in governing

the status of populations, because even landscape-level

effects were probably caused by availability

of habitat during the terrestrial stage, rather than

by metapopulation processes.

Ecology, 2005, V86, N7, JUL, pp 1936-1947

05.3-75

Meta-analysis of farmland biodiversity within

set-aside land: Reply to Kleijn and Baldi

van Buskirk J, Willi Y

Australia, Switzerland

Biodiversity , Agriculture, Soil Sciences , Ecology

Conservation Biology, 2005, V19, N3, JUN,

pp 967-968

05.3-76

Biological flora of central Europe: Solidago

gigantea Aiton

Weber E, Jakobs G

Switzerland

Plant Sciences , Ecology , Biodiversity

Solidago gigantea is a rhizomatous perennial herb native

to northern America and introduced in Europe. It is

a serious invader of disturbed mesic sites, often forming

dense monospecific stands. We review the literature on

taxonomy, morphology, population biology, cytology,

physiology, chemistry, and ecology of this species.

Flora, 2005, V200, N2, pp 109-118

46

Global Change Abstracts – The Swiss Contribution

1.2 TERRESTRIAL ECOSYSTEMS

05.3-77

Modeling the interacting effects of browsing and

shading on mountain forest tree regeneration

(Picea abies)

Weisberg P J, Bonavia F, Bugmann H

Switzerland

Modelling , Forestry , Plant Sciences

Although ungulate herbivory influences forest dynamics

over a variety of spatial and temporal scales, relatively

few models have been developed for investigating

browsing effects on tree regeneration processes.

We describe a new, mechanistic model (HUNGER)

that modifies a well-established mathematical formulation

for plant nutrient transport and conversion processes

to simulate sapling response to ungulate

browsing and light availability. The HUNGER model

simulates primary production, height and diameter

growth, dry matter allocation, and population dynamics

of tree saplings at the scale of small (e.g. 0.001

ha) regeneration patches. The model was applied to

Picea abies saplings in mountain forests of eastern

Switzerland after calibration based on data for sapling

height growth, radial growth, and biomass components

under varying light conditions. Independent

data were used to test the ability of the model to represent

sapling responses to browsing. The model

slightly over-predicted sapling height, while no significant

differences were found between simulated and

observed basal diameter, total biomass or leaf

biomass. Model experiments were conducted to explore

the interactive effects of winter browsing intensity

and relative light availability upon sapling net

growth. Simulated shading effects were gradual until

approximately 40% relative light availability (if browsing

pressure was low) or 60% relative light availability

(if browsing pressure was high). Below these values,

the model simulates sharp declines in net growth rate.

Model results suggest nonlinear responses to browsing

and light availability, and the existence of light intensity

thresholds for forest regeneration that should

be relevant for management activities affecting deer

density and crown cover.

Ecological Modelling, 2005, V185, N2-4, JUL 10,

pp 213-230

05.3-78

Epiphytic macrolichen communities along

regional gradients in northern Norway

Werth S, Tommervik H, Elvebakk A

Norway, Switzerland

Forestry , Social Sciences , Meteorology &

Atmospheric Sciences , Ecology , Plant Sciences

Question: What are the relative influences of human

impact, macroclimate, geographic location and habitat

related environmental differences on species composition

of boreal epiphytic macrolichen communities?

Location: Troms county in northern Norway. Methods:


Detrended Correspondence Analysis revealed the

main gradient structure in lists of epiphytic macrolichen

species from deciduous forests. By Canonical

Correspondence Analysis with variance partitioning,

the relative amount of variance in macrolichen

species composition attributable to human impact,

macroclimate, spatial context and environmental differences

was quantified. Results: There was no significant

effect of human impact Oil species composition

of epiphytic macrolichens of deciduous forests.

Macroclimate was the most important factor determining

epiphytic macrolichen communities, which were

also strongly influenced by ecological differences

Such as forest stand properties. Conclusions: Epiphytic

macrolichen communities are determined by a

macroclimatic gradient from the coastline to the interior

of central north Norway. In marked contrast, the

species composition of epiphytic macrolichen communities

seems to be unaffected by human impact in the

study area, where air pollution was marginal.

Journal of Vegetation Science, 2005, V16, N2, APR,

pp 199-208

05.3-79

Carbon dynamics in a temperate grassland soil

after 9 years exposure to elevated CO2 (Swiss

FACE)

Xie Z B, Cadisch G, Edwards G, Baggs E M, Blum H

Peoples R China, England, Scotland, Switzerland,

New Zealand

Agriculture, Soil Sciences , Geochemistry &

Geophysics , Plant Sciences

Elevated pCO(2) increases the net primary production,

C/N ratio, and C input to the soil and hence provides

opportunities to sequester CO2-C in soils to mitigate

anthropogenic CO2. The Swiss 9 y grassland

FACE (free air carbon-dioxide enrichment) experiment

enabled us to explore the potential of elevated

pCO(2) (60 Pa), plant species (Lolium perenne L. and

Trifolium repens L.) and nitrogen fertilization (140 and

540 kg ha(-1) y(-1)) on carbon sequestration and mineralization

by a temperate grassland soil. Use of C-13

in combination with respired CO2 enabled the identification

of the origins of active fractions of soil organic

carbon. Elevated pCO(2) had no significant effect on

total soil carbon, and total soil carbon was also independent

of plant species and nitrogen fertilization.

However, new (FACE-derived depleted C-13) input of

carbon into the soil in the elevated pCO(2) treatments

was dependent on nitrogen fertilization and plant

species. New carbon input into the top 15 cm of soil

from L. perennne high nitrogen (LPH), L. perenne low

nitrogen (LPL) and T. repens low nitrogen (TRL) treatments

during the 9 y elevated pCO(2) experiment was

9.3 &PLUSMN; 2.0, 12.1 &PLUSMN; 1.8 and 6.8

&PLUSMN; 2.7 Mg C ha(-1), respectively. Fractions of

FACE- derived carbon in less protected soil particles

1.2 TERRESTRIAL ECOSYSTEMS

> 53 μ m in size were higher than in < 53

μ m particles. In addition, elevated pCO(2) increased

CO2 emission over the 118 d incubation by

55, 61 and 13% from undisturbed soil from LPH, LPL

and TRL treatments, respectively; but only by 13, 36,

and 18%, respectively, from disturbed soil (without

roots). Higher input of new carbon led to increased

decomposition of older soil organic matter (priming effect),

which was driven by the quantity (mainly roots)

of newly input carbon (L. perenne) as well as the

quality of old soil carbon (e.g. higher recalcitrance in

T. repens). Based on these results, the potential of

well managed and established temperate grassland

soils to sequester carbon under continued increasing

concentrations of atmospheric CO2 appears to be

rather limited.

Soil Biology Biochemistry, 2005, V37, N7, JUL,

pp 1387-1395

05.3-80

Increasing population density and seed

production with altitude in Eritrichium nanum

(Boraginaceae) - An arctic alpine obligatory

seeder

Zoller H, Lenzin H, Rusterholz H P, Stöcklin J

Switzerland

Plant Sciences , Biodiversity

At 17 sites in the European Alps (2170-3310 m), the

population density and seed production of the high

alpine cushion plant Eritrichium nanum were investigated.

Recruitment in this non-clonal species relies

exclusively on seeds. The population density rose significantly

with increasing altitude. A mean number of

368 seeds per m2 was observed. Whereas the quantity

of the generative rosettes (metamers) was relatively

constant, the annual seed production strongly

varied and was found vulnerable, particularly in 1996,

when it was suppressed by unfavorable weather conditions.

In 1997 seed production again reached the

usual level, when about the same amounts of seeds

were recorded as in previous years, indicating the

strong resistance of elevated E. nanum populations

against the severe climate at high altitudes. With rising

population density, E. nanum produces distinctly

higher seed numbers. This increasing amount of

seeds seems essential for the persistence of its uppermost

populations. Our results indicate that it is

caused by the rising number of rosettes/ surface and

not a higher reproduction by single rosettes. Compared

to other alpine species, the seed weight of E.

nanum (average 0.76 mg) is high. Most of its neighboring

species are clonal, producing much lighter

seeds. The strategy of producing heavy seeds favors

successful recruitment and appears to be decisive for

an obligatory seeder such as E. nanum.

Arctic Antarctic and Alpine Research, 2005, V37, N1,

FEB, pp 41-48

Global Change Abstracts – The Swiss Contribution 47


05.3-81

No down-regulation of leaf photosynthesis in mature

forest trees after three years of exposure to

elevated CO2

Zotz G, Pepin S, Körner C

Switzerland

Plant Sciences , Forestry

The photosynthetic responses of six species of mature

forest trees to long-term exposure to elevated

CO2 (ca. 530 ppm) were determined at the Swiss

Canopy Crane (SCC) site near Basel, Switzerland, in

the third year of growth in elevated CO2, using web-

FACE technology, net photosynthesis (A(s)) in fully

sunlit, upper canopy foliage was stimulated by ca.

05.3-82

Variability of available cadmium in relation to soil

properties and landuse in an arid region in central

Iran

Amini M, Khademi H, Afyuni M, Abbaspour K C

Iran, Switzerland

Agriculture, Soil Sciences , Geochemistry &

Geophysics , Toxicology

Due to potential problems associated with their toxicities,

concentration of heavy metals in soils is of great

environmental concern. To evaluate Cd content, its

spatial pattern, and availability in the surface soils of

agricultural, industrial and urban regions of Isfahan,

central Iran, we collected 255 topsoil samples (0-20

cm) from the nodes of an irregular grid in a study area

of 6800 km(2). In the soil samples we measured total

and DTPA- extractable Cd concentrations, soil pH, organic

mater (OM), clay content, soil salinity, and chloride

concentration. The total Cd concentration in 90%

of the samples exceeded the suggested Swiss thresholds

of 0.8 mg kg(-1). Landuse had a significant effect

on total concentration of Cd in the soil but had no effect

on DTPA- extractable Cd. High values of total Cd

were found in industrial and urban areas whereas low

values occurred in uncultivated lands. The correlation

analysis revealed that soil salinity alone explained

36% of the Cd variation in the entire study area. The

correlation was particularly strong in uncultivated areas

(R-2 = 0.70). Spatial analysis of available Cd using

indicator kriging and soil salinity showed a spatial

co-occurrence of these two variables.

Water Air and Soil Pollution, 2005, V162, N1-4, MAR,

pp 205-218

48

1.2 TERRESTRIAL ECOSYSTEMS / 1.3 SOIL AND LITHOSPHERE

1.3 Soil and Lithosphere

Global Change Abstracts – The Swiss Contribution

40% compared to ambient controls. This enhancement

did not differ from the instantaneous increase in

A, found in ambient-grown leaves that were temporarily

measured at elevated CO2. A complete lack of

down-regulation of photosynthesis was found in all

species and in both the early and the late growing

season. Neither was leaf nitrogen content significantly

affected by long-term exposure to elevated CO2. Our

results document a persistent enhancement in leaf

level photosynthesis in response to elevated CO2 in

mature forest trees over a period of three years. Circumstantial

evidence suggests that the additional assimilates

feed into large sinks other than stem and

shoot growth.

Plant Biology, 2005, V7, N4, JUL, pp 369-374

05.3-83

Effects of increasing fire frequency on black

carbon and organic matter in Podzols of Siberian

Scots pine forests

Czimczik C I, Schmidt M W I, Schulze E D

Germany, Switzerland

Forestry , Plant Sciences , Geochemistry &

Geophysics , Agriculture, Soil Sciences

Fires in boreal forests frequently convert organic matter

in the organic layer to black carbon, but we know

little of how changing fire frequency alters the amount,

composition and distribution of black carbon and organic

matter within soils, or affects podzolization. We

compared black carbon and organic matter (organic

carbon and nitrogen) in soils of three Siberian Scots

pine forests with frequent, moderately frequent and infrequent

fires. Black carbon did not significantly contribute

to the storage of organic matter, most likely because

it is consumed by intense fires. We found 99%

of black carbon in the organic layer; maximum stocks

were 72 g m(-2). Less intense fires consumed only

parts of the organic layer and converted some organic

matter to black carbon (> 5 g m(-2)), whereas more

intense fires consumed almost the entire organic layer.

In the upper 0.25 m of the mineral soil, black carbon

stocks were 0.1 g m(-2) in the infrequent fire

regime. After fire, organic carbon and nitrogen in the

organic layer accumulated with an estimated rate of

14.4 g C m(-2) year(-1) or 0.241 g N m(-2) year(-1).

Maximum stocks 140 years after fire were 2190 g organic

C m(-2) and 40 g N m(-2), with no differences

among fire regimes. With increasing fire frequency,

stocks of organic carbon increased from 600 to 1100

g m(-2) (0-0.25 m). Stocks of nitrogen in the mineral

soil were similar among the regimes (0.04 g m (-2)).

We found that greater intensities of fire reduce

amounts of organic matter in the organic layer but that


the greater frequencies may slightly increase amounts

in the mineral soil.

European Journal of Soil Science, 2005, V56, N3,

JUN, pp 417-428

05.3-84

Carbon and nitrogen isotope composition of bulk

soils, particle-size fractions and organic material

after treatment with hydrofluoric acid

Schmidt M W I, Gleixner G

Switzerland, Germany

Geochemistry & Geophysics , Agriculture, Soil

Sciences , Limnology

Soils and sediments contain only small amounts of organic

matter, and large concentrations of paramagnetic

metals can give poor solid-state nuclear magnetic

resonance (NMR) spectra of organic matter. Pretreatment

of samples with hydrofluoric acid (HF) dissolves

significant proportions of the mineral matrix

and extracts paramagnetic elements. We investigated

the effects of 10% HF treatment on the stable isotope

content of carbon (C) and nitrogen (N) of organic matter

from soils, composts and shales. Additionally we

inferred molecular and isotopic characteristics of lost

materials from calculations of isotope mass balances.

Treatment with HF enriched C and N in mineral samples

substantially (factors 2.5-42.4), except for Podzol

B horizons (1.1-1.7) and organic material (1.0-1.3) .

After treatment most of the C (59.7-91.7%) and N

(53.7-86.6%) was recovered, although changing C/N

ratios often indicated a preferential loss of N-rich material.

Isotope ratios of C and N in the remaining material

became more negative when net alterations exceeded

0.3 parts per thousand. The isotope ratios of

the lost material contained more C-13 (1-2 parts per

thousand) and N-15 (1-4 parts per thousand) than the

initial organic matter. Acid hydrolysis typically removes

proteins, amino acids and polysaccharides, all

of which are enriched in C-13, and in the case of proteins

and amino acids, enriched in N-15 as well. We

conclude that HF treatment released fresh, soluble,

probably microbial, biomass in addition to carbohydrates.

Net changes of the bulk chemical composition

of organic matter were small for most soils, size fractions

and plant material, but not for samples containing

little organic matter, or those rich in easily soluble

organic matter associated with iron oxides, such as

Podzol B horizons.

European Journal of Soil Science, 2005, V56, N3,

JUN, pp 407-416

05.3-85

Modelling the behaviour of a large landslide with

respect to hydrogeological and geomechanical

parameter heterogeneity

Tacher L, Bonnard C, Laloui L, Parriaux A

1.3 SOIL AND LITHOSPHERE

Switzerland

Modelling , Geochemistry & Geophysics , Hydrology ,

Agriculture, Soil Sciences

Thanks to a sophisticated transient hydrogeological

modelling allowing the determination of the pore pressure

fields in La Frasse landslide mass during a crisis,

it has been possible to model the mechanical behaviour

of the slide and obtain results that prove to be

similar to the monitored data, in terms of peak velocity,

distribution of velocity with time and space and total

displacements. Such results are reached only

when appropriate constitutive modelling laws are

used, and when geotechnical tests supply all the required

parameters. The main results concern the potential

effect of a drainage system during a crisis, like

the one experienced in 1994. It can include vertical

boreholes equipped with pumps or drains drilled from

a gallery. The draining system reduces horizontal displacements

down to 5% of the values modelled during

the crisis. This effect, which appears to extend over a

large width, will be even more significant if the boreholes

discharge the drained water into the gallery, due

to its extension in the presently stabilised landslide

mass below the active zone. The modelling tools developed

for La Frasse landslide thus provide all the

necessary information to optimise the drainage

scheme.

Landslides, 2005, V2, N1, APR, pp 3-14

05.3-86

Simultaneous estimation of diffusive volatile

organic compound (VOC) fluxes and non-aqueous

phase liquid (NAPL) saturation in the vadose zone

Werner D, Broholm M, Höhener P

Switzerland, Denmark, England

Agriculture, Soil Sciences , Geochemistry &

Geophysics

Soil-gas monitoring is a widely used tool to observe

the migration of volatile organic compounds (VOCs)

at contaminated sites. By combining this technique

with natural gradient tracer methods, diffusive contaminant

fluxes can be measured in situ, and nonaqueous

phase liquid (NAPL) can be detected and

roughly quantified. This work describes the new approach

and its application at a field site in Denmark

with an emplaced NAPL contamination. Soil-gas

probes with a low dead volume were installed at 1-m

depths in the sandy vadose zone, and a small volume

of gas containing conservative and partitioning tracers

was injected. Soil-gas samples were withdrawn subsequently

during 1 to 4 h and analyzed simultaneously

for VOCs and tracers. Tracers detected the NAPL

reliably, and the combined data allowed for a close

delineation of the source zone. The calculated NAPL

saturation deviated by up to a factor of 3 from the

analyses of soil cores. Better agreement was found

by taking the NAPL composition into consideration,

which is, however, generally unknown at the actual

Global Change Abstracts – The Swiss Contribution 49


field sites. In addition, the tracers were also used to

estimate effective diffusion coefficients in situ, which

varied by a factor of 2 between various locations.

From these data, diffusive contaminant vapor fluxes

were quantified without additional laboratory experi-

05.3-87

Triaxial constant stress and constant strain rate

tests on ice-rich permafrost samples

Arenson L, Springman S

Switzerland

Cryology / Glaciology

A range of mechanical compression tests were conducted

on frozen soil samples at temperatures close

to the melting point of ice to determine both the creep

and the strength properties under triaxial stress conditions.

The samples were obtained from two rock

glaciers in the Swiss Alps. For comparison, additional

samples were prepared artificially for testing. The results

showed that the minimum creep strain rate increases

exponentially with increasing temperature

and applied deviatoric stress. The applied strain rate

is the main parameter influencing resistance. However,

test results show that the micromechanical behaviour

is similar for all tests and independent of the

applied loading condition. Measurements of the volumetric

strain showed that the sample composition has

a major influence, so samples with high air void ratios

resulted in continuous contraction (i.e., reduction of

the sample volume), whereas samples with low volumetric

air and ice contents demonstrated dilatant behaviour.

Canadian Geotechnical Journal, 2005, V42, N2, APR,

pp 412-430

05.3-88

Mathematical descriptions for the behaviour of

ice-rich frozen soils at temperatures close to 0° C

Arenson L, Springman S

Switzerland

Cryology / Glaciology

With the use of creep and constant strain rate (CSR)

tests, mathematical formulations were found that describe

the thermomechanical behaviour of ice-rich

frozen soils. A Glen-type relationship was chosen for

the formulation of minimum creep strain rates at temperatures

between -4° C and -1° C. The shear

strength of the material could be described by a Mohr-

Coulomb failure criterion. Furthermore, it was possible

to compare the creep behaviour with the strength of

50

1.3 SOIL AND LITHOSPHERE / 1.4 CRYOSPHERE

Global Change Abstracts – The Swiss Contribution

1.4 Cryosphere

ments or the use of empirical relationships. The new

approach yields a better site investigation with a few

additional measurements.

Ground Water Monitoring and Remediation, 2005,

V25, N2, SPR, pp 59-67

similar soils under constant strain rates. The minimum

creep strain rate increases proportionally as the temperature

approaches the melting point of the ice,

which can be attributed to the increasing amount of

unfrozen water, which strongly influences the mechanical

response. Even though only a few tests

could be used for the determination of the angle of

friction and the apparent cohesion, the trend showed

that the volumetric ice content influences both parameters,

but only the latter seems to be influenced by

the temperature and the applied compression strain

rate.

Canadian Geotechnical Journal, 2005, V42, N2, APR,

pp 431-442

05.3-89

The influence of seasonally frozen soil on the

snowmelt runoff at two Alpine sites in southern

Switzerland

Bayard D, Stähli M, Parriaux A, Flühler H

Switzerland

Agriculture, Soil Sciences , Hydrology , Cryology /

Glaciology

In spring, snowmelt releases huge quantities of meltwater,

affecting the hydrology of Alpine areas. Seasonal

soil frost influences these water fluxes by locally

decreasing the infiltration capacity of the soil. resulting

in an increased amount of surface runoff. The main

goal of this study was to investigate the spatial variability

of the seasonal frost depth and to quantify by

how much this seasonal soil frost affects the snowmelt

discharge. For this purpose. tin extensive field

study was run for two winter seasons (2000/2001 and

2001/2002) at Gd St Bernard (2470 m) and Hannigalp

(2090 m) in the southern Swiss Alps. The different

components of the water balance (lateral runoff, deep

percolation, liquid soil water content) were measured

on delimited plots of 5 m(2). The two winters investigated

had opposing weather and soil frost conditions:

in the first winter a thick snowpack prevented the formation

of soil frost, whereas in the second winter little

snow fell until January. which produced a deep and

persistent soil frost. We classified the snowmelt

events into several classes (mid-winter. late winter.

spring and post-spring) and analysed the significance

of the different water flow components for each melt


situation. While 90-100%, of melt water infiltrated into

the ground during the first winter, 25-35% of melt water

ran off laterally in the second. mainly during late

winter and spring snowmelt events. In that second

winter, the soil infiltration capacity was primarily reduced

by the presence of a basal ice sheet after midwinter

melt events.

Journal of Hydrology, 2005, V309, N1-4, JUL 19,

pp 66-84

05.3-90

Isotopic view on nitrate loss in Antarctic surface

snow

Blunier T, Floch G L, Jacobi H W, Quansah E

Switzerland, Germany

Chemistry , Meteorology & Atmospheric Sciences ,

Cryology / Glaciology

Massive post-depositional processes alter the nitrate

concentration in polar firn where the annual snow accumulation

is low. This hinders a direct atmospheric

interpretation of the ice core nitrate record. Fractionation

of nitrate isotopes during post-depositional nitrate

loss may allow estimating the amount of nitrate loss in

the past. We measured delta(15)N of nitrate in two

Antarctic surface cores from the Dome C area. In concert

with the known concentration decrease with

depth we observe an increase in the isotopic signature.

Assuming a Rayleigh type process we find an

isotope effect of epsilon = - 54 parts per thousand.

We measured the fractionation factor for photolysis in

the laboratory and obtained epsilon = - 11.7 +/- 1.4

parts per thousand. As the observed fractionation factor

in the firn is much lower this rules out that photolysis

in the surface snow is the main process leading to

the dramatic nitrate loss in the top centimeters of the

firn.

Geophysical Research Letters, 2005, V32, N13,

JUL 8, ARTN: L13501

05.3-91

Validation of the energy budget of an alpine

snowpack simulated by several snow models

(SnowMIP project)

Etchevers P, Martin E, Brown R, Fierz C, Lejeune Y,

Bazile E, Boone A, Dai Y, Essery R, Fernandez A,

Gusev Y, Jordan R, Koren V, Kowalcyzk E,

Nasonova N O, Pyles R D, Schlosser A, Shmakin A B,

Smirnova T G, Strasser U, Verseghy D, Yamazaki T,

Yang Z L

France, Canada, Switzerland, Peoples R China, England,

Spain, Russia, USA, Australia, Germany, Japan

Cryology / Glaciology , Hydrology , Modelling ,

Meteorology & Atmospheric Sciences

Many snow models have been developed for various

applications such as hydrology, global atmospheric

1.4 CRYOSPHERE

circulation models and avalanche forecasting. The degree

dcomplexity of these models is highly, variable,

ranging from simple index methods to multilayer models

that simulate snow-cover stratigraphy and texture.

In the framework of the Snow Model Intercomparison

Project (Snow MIP), 23 models were compared using

observed Meteorological parameters from two mountainous

alpine sites. The analysis here focuses on validation

of snow energy-budget simulations. Albedo

and snow surface temperature observations allow

identification of the more realistic simulations and

quantification of errors for two components of the energy

budget: the net short- and longwave radiation. In

particular, the different albedo parameterizations are

evaluated for different snowpack states (in winter and

spring). Analysis of results during the melting period

allows an investigation of the different ways of partitioning

the energy fluxes and reveals 0. 1 the complex

feedbacks which Occur when simulating the snow energy

budget. Particular attention is paid to the impact

of model complexity on the energy-budget components.

The model complexity has a major role for the

net longwave radiation calculation, whereas the albedo

parameterization is the most significant factor explaining

the accuracy of the net shortwave radiation

simulation.

Annals of Glaciology Vol 38 2004, 2004, V38,

pp 150-158

05.3-92

Operational sub-pixel snow mapping over the

Alps with NOAA AVHRR data

Foppa N, Wunderle S, Hauser A, Oesch D, Kuchen F

Switzerland

Mapping , Cryology / Glaciology , Hydrology , Forestry

This study is part of research activities concentrating

on the real- time application of the U.S. National

Oceanic and Atmospheric Administration (NOAA) Advanced

Very High Resolution Radiometer (AVHRR)

sensor for snow-cover analysis of the European Alps.

For mapping snow cover in heterogeneous terrain, we

implement the widely used linear spectral mixture algorithm

to estimate snow cover at sub- pixel scale.

Principal component analysis, including the reflective

part of AVHRR channel 3, is used to estimate fractions

of "snow" and "not snow" within a pixel, using

linear mixture modeling. The combination of these

features leads to a fast, simple solution for operational

and near-real-time processing. The presented algorithm

is applied on the European Alps on 17 January

2003 and successfully maps snow at sub-pixel scale.

The detailed snow-cover information makes it easy to

recognize the complex topography of the Alps, more

so than with either a classic binary map or a Moderate

Resolution Imaging Spectroradiometer (MODIS) snow

product. The sub-pixel algorithm reasonably identifies

snow-cover fractions in regions and at altitudes where

neither the classic binary map nor the MODIS algorithm

detects any snow. Differences concerning the

Global Change Abstracts – The Swiss Contribution 51


snow distribution are found in forested areas as well

as in the lowest- elevation zones. The algorithm substantially

improves snow mapping over complex topography

for operational and near-real time applications.

Annals of Glaciology Vol 38 2004, 2004, V38,

pp 245-252

05.3-93

SNOWPACK model simulations for snow in

Hokkaido, Japan

Hirashima H, Nishimura K, Baba E, Hachikubo A,

Lehning M

Japan, Switzerland

Cryology / Glaciology , Modelling , Hydrology ,

Meteorology & Atmospheric Sciences

Numerical simulations using SNOWPACK, a snowcover

model, were carried out to confirm the model's

applicability to conditions in Hokkaido, Japan, where

temperatures are fairly low and for 3 months the snow

surface is usually dry except during occasional periods

of rain or above-freezing temperatures. The simulations

were conducted for Sapporo, Kitami and

Niseko using meteorological data, and the results

were compared with the observed snow profiles. In

Sapporo, snow-profile observations were carried out

every day for two winters. In Niseko, one of the most

popular ski resorts in Japan, an avalanche accident

occurred on 28 January 1998 and a snow pit was dug

through the fracture line the next morning. The simulated

snow profiles agreed fairly well with the observed

ones. However, near the surface we observed

depth hoar, which can be an important factor in

avalanche release after successive snowfalls, that the

model did not reproduce distinctly. Extending the

model's metamorphism laws with an expression of

depth-hoar formation under a large temperature gradient,

as formulated from an experiment by Fukuzawa

and Akitaya (1993), the model reproduced the depth

hoar adequately.

Annals of Glaciology Vol 38 2004, 2004, V38,

pp 123-129

05.3-94

Reconciling different observational data sets from

Surface Heat Budget of the Arctic Ocean (SHEBA)

for model validation purposes

Huwald H, Tremblay L B, Blatter H

Switzerland, USA

Modelling , Oceanography , Cryology / Glaciology ,

Meteorology & Atmospheric Sciences

(1) Observations from the Surface Heat Budget of the

Arctic Ocean (SHEBA) are analyzed to develop a

consistent data set suitable for the validation of snow

and sea ice components used in climate models.

52

Global Change Abstracts – The Swiss Contribution

1.4 CRYOSPHERE

Since the snow depth is a crucial variable to properly

determine the ice thickness evolution, several methods

are tested to estimate the actual snow depth at

the exact location of the measured internal temperatures.

Snow and ice thickness gauge measurements

show high spatial variability at small spatial scales.

Consequently, individual measurements of snow/ice

thickness are not representative of the thickness at

the locations where temperature profiles were measured.

Observed skin temperatures and snow internal

temperature profiles suggest that the mean winter

snow cover at the reference mass balance site was

thicker by 11 cm when compared with gauge observations

at a small distance from that reference site. The

mean winter snow cover thickness measured at the

SHEBA mass balance site, Pittsburgh, is larger by a

factor of 2.3 when compared to the snow depth derived

from precipitation measurements. Assuming

continuity of heat fluxes at the snow-ice interface, an

effective snow thermal conductivity of 0.50 Wm(-1) K-

1 is calculated. This is significantly higher than values

generally used in climate models (0.31 Wm(-1) K-1)

or derived from in situ measurements (0.14 Wm(-1) K-

1) at SHEBA. Ocean heat fluxes, inferred from ice

thickness and internal temperature measurements at

various sites, are very consistent and match reasonably

well those derived from turbulence measurements

and a bulk formulation. A heat budget of surface

fluxes shows a mean annual net imbalance of

1.5 Wm(-2), with a mean energy deficit of 3.5 Wm(-2)

during winter and a mean surplus of 6.4 Wm(-2) during

summer.

Journal of Geophysical Research Oceans, 2005,

V110, NC5, MAY 14, ARTN: C05009

05.3-95

A multilayer sigma-coordinate thermodynamic sea

ice model: Validation against Surface Heat Budget

of the Arctic Ocean (SHEBA)/Sea Ice Model

Intercomparison Project Part 2 (SIMIP2) data

Huwald H, Tremblay L B, Blatter H

Switzerland, USA

Modelling , Oceanography , Cryology / Glaciology ,

Mapping

(1) A new multilayer sigma-coordinate thermodynamic

sea ice model is presented. The model employs a coordinate

transformation which maps the thickness of

the snow and ice slabs onto unity intervals and thus

enables automatic relayering when the snow or ice

thickness changes. This is done through an advection

term which naturally appears in the transformed energy

equation. Unlike previous approaches, the model

conserves the total energy per layer (Jm(-2) as opposed

to Jm(-3)), which takes into account the

changes in internal energy associated with thickness

changes. This model was then tested against observational

data from the Surface Heat Budget of the

Arctic Ocean (SHEBA) experiment in the context of

the Sea Ice Model Intercomparison Project, Part 2,


Thermodynamics (SIMIP2). In general, the model reproduces

the observed internal snow-ice temperature

and the ice thickness evolution very well. Results

show that the ice thickness evolution is very sensitive

to the ocean heat flux (F-ocn) and the thickness of the

snow cover in winter. Given that the spatial variability

in snow depth at small scale is large, the specification

of the snow depth temporal evolution is crucial for an

intercomparison project. Since F-ocn in SIMIP2 is calculated

as a residual of the observed basal growth

rates and heat conduction, the salinity of newly

formed ice used in the simulations must be consistent

with that used to derive F-ocn. Simulated and observed

snow surface and snow-ice interface temperatures

suggest that not enough heat is conducted

through the snow layer even when using a snow thermal

conductivity as large as 0.50 Wm(-1) K-1 ( value

derived from observed snow and ice internal temperature

profiles). A surface energy budget of simulated

and observed energy fluxes confirms this finding.

Journal of Geophysical Research Oceans, 2005,

V110, NC5, MAY 14, ARTN: C05010

05.3-96

Advance mechanisms of rock glaciers

Kaab A, Reichmuth T

Switzerland

Cryology / Glaciology , Geomorphology

Rock glacier advance is believed to be the result of

the advection of frozen debris to and over the front,

(partial) melt-out of ice, and incorporation and subsequent

overriding of the mass at the base of the rock

glacier. In this contribution, an approach to measure

mass balance and transport within rock glacier fronts

is presented. The technique is applied to Gruben and

Suvretta rock glaciers, Swiss Alps. The results confirm

a 'conveyor belt'-like advance mechanism for

both features. At the Gruben rock glacier front, an average

excess ice content of approximately 65% was

detected, 15% more than at Suvretta rock glacier. The

frontal part of Suvretta rock glacier turned out to have

a linear velocity profile over the entire thickness. At

Gruben rock glacier, the horizontal mass transport is,

for the most part, concentrated in a 5-10 m thick surface

layer.

Permafrost and Periglacial Processes, 2005, V16, N2,

APR-JUN, pp 187-193

05.3-97

Impact of artificial snow and ski-slope grooming

on snowpack properties and soil thermal regime

in a sub-alpine ski area

Keller T, Pielmeier C, Rixen C, Gadient F, Gustafsson

D, Stahli M

Sweden, Switzerland

Cryology / Glaciology , Hydrology , Agriculture,

Soil Sciences

1.4 CRYOSPHERE

Studies have indicated that the soil on groomed ski

slopes may be subjected to more pronounced cooling

than the soil below a natural snowpack. We analyzed

the thermal impacts of ski-slope preparation in a subalpine

ski resort in central Switzerland (1100 in a.s.l.)

where artificial snow was produced. Physical snow

properties and soil temperature measurements were

carried out on the ski slope and off- piste during winter

1999/2000. The numerical soil-vegetation- atmosphere

transfer model COUP was run for both locations,

with a new option to simulate the snowpack development

on a groomed ski slope. Snow density.

snow hardness and thermal conductivity were significantly

higher on the ski slope than in the natural

snowpack. However, these differences did rift affect

the cooling of the soil, since no difference was observed

between the ski slope and the natural snow

cover. This might be because cold periods were rare

and short and thus any snowpack could protect the

soil from freezing. The major impact of the ski-slope

grooming was a 4 week delay in snowmelt and soil

warming at the end of the season. The newly implemented

option proved to be a useful strategy for simulating

the snowpack of a ski slope. However, snow

density was underestimated by the model as it could

not account adequately for compaction due to grooming

traffic. Our study demonstrates that there is no

site-independent answer as to whether a groomed

snowpack affects the thermal conditions in the soil.

Annals of Glaciology Vol 38 2004, 2004, V38,

pp 314-318

05.3-98

Estimating snow conditions in Finland in the late

21st century using the SNOWPACK model with

regional climate scenario data as input

Rasmus S, Raisanen J, Lehning M

Finland, Sweden, Switzerland

Cryology / Glaciology , Modelling , Hydrology ,

Meteorology & Atmospheric Sciences

An assessment of possible snow changes in a changing

climate for Finland is presented. The snowpack

structure model SNOWPACK (developed at the Swiss

Federal Institute for Snow and Avalanche Research)

was used for calculating snow conditions at six different

locations in Finland for the decades 1980-89 and

2080-89. Regional climate model (RCAO) data from

the Rossby Centre, Sweden, were used as input to

the SNOWPACK model. Ten years from the RCAO

control run and scenario run Were chosen, and the

snow conditions for different snow zones were calculated

for these winters. The snow-cover depth and duration

decreased at all locations in the scenario run

cases, and the snow-cover quality also changed between

the control and scenario runs: grains were bigger,

snow was warmer and denser, and the fraction of

faceted snow decreased while the fraction of icy or

melting snow increased, even in mid-winter. Finally,

the variability between different global climate predictions

was analyzed. Significant differences were

Global Change Abstracts – The Swiss Contribution 53


found between different climate-model outputs. The

inter-model variable is comparable to the interannual

variability of a single model. The qualitative Conclusions

from the scenario run do not critically depend oil

the climate-model variability.

Annals of Glaciology Vol 38 2004, 2004, V38,

pp 238-244

05.3-99

A new in situ sensor for large-scale snow-cover

monitoring

Stähli M, Stacheder M, Gustafsson D, Schlaeger S,

Schneebel M, Brandelik A

Switzerland, Germany

Cryology / Glaciology , Hydrology

A new in situ sensor for the simultaneous measurement

of snow water equivalent, snow density and liquid-water

content is presented in this paper. The system

consists of radio frequency transmission lines of

up to 25 in length cast in a flat PVC band, which can

be set up either horizontally to monitor single snowlayer

properties or sloping from a mast to the soil surface

to determine vertical snowpack properties. The

dielectric coefficient along the flat-band cable is measured

with a time-domain reflectometer at high frequencies,

and with a low-frequency impedance analyzer.

The performance of the sensor system was

tested during two winter seasons (2001-03) at the

high-alpine test site Weissfluhjoch, Davos, Switzerland.

The cable suspension and set-up of the sloping

cable was shown to be critical with regard to stability

and the formation of unwanted air gaps along the cable.

Overall, the sensing system proved quite robust

and produced results in agreement with manual

snowpack observations.

Annals of Glaciology Vol 38 2004, 2004, V38,

pp 273-278

05.3-100

Pol-InSAR observations from an Alpine glacier in

the cold infiltration zone at L- and P-band

Stebler O, Schwerzmann A, Lüthi M, Meier E,

Nuesch D

Switzerland, USA

Cryology / Glaciology , Geochemistry & Geophysics

In the frame of the Swiss Alpine Airborne SAR Experiment

2003 (SASARE), multitemporal/multibaseline

polarimetric synthetic aperture radar (SAR) interferometry

(Pol-InSAR) datasets were acquired with the

54

Global Change Abstracts – The Swiss Contribution

1.4 CRYOSPHERE

German Experimental SAR (E-SAR) platform at Land

P-band in the region of the Aletsch glacier in

Switzerland. For SASARE, several sub-test-sites had

been selected below and significantly above the equilibrium

line. We provide results from the analysis of

the multibaseline Pol-InSAR L- and P-band measurements

of the polarization-dependent complex interferometric

coherence of an Alpine glacier in the cold infiltration

zone. Interferometric volume decorrelation is

demonstrated as a function of polarization. Conventional

polarimetric decomposition techniques confirm

the polarization-dependent backscattering properties

of the analyzed snow and ice surfaces.

Ieee Geoscience and Remote Sensing Letters, 2005,

V2, N3, JUL, pp 357-361

05.3-101

Application of the numerical snowpack model

(SNOWPACK) to the wet- snow region in Japan

Yamaguchi S, Sato A, Lehning M

Japan, Switzerland

Modelling , Cryology / Glaciology , Hydrology

The snow-cover model SNOWPACK was applied to

the wet-snow areas of Japan. Simulated variations of

snow type, snow depth and weight, profiles of snow

density, temperature and liquid-water content were

compared with snow-pit measurements. The snowdepth

Simulation during early winter agreed with the

measurements, but the differences between the simulation

and the measurements increased during the

course of the melt season. These differences were

caused by underestimation of the energy balance at

the snow surface, mainly that regarding sensible-heat

flux during the melt season. The underestimation was

caused by the implicit numerical treatment of the

heat-tran sport equation. Consistent with the underestimation

of snowmelt, simulated metamorphosis of

compacted particles into melt forms was slower than

the change shown by the measurements, and faceted

snow particles, which constitute a snow type not actually

found in the study area, sometimes appeared in

the model. The inaccurate melt treatment also influence

d simulated densities, which were larger than

the measurements at small densities, while thev were

smaller than the measurements at laroe densities.

Greater accuracy was achieved when all empirical

compressive viscosiq forri-itilation for wet snows in

Japan was introduced. A new version of SNOWPACK,

with all accurate treatment of melt processes.. is avallable.

Annals of Glaciology Vol 38 2004, 2004, V38,

pp 266-272


05.3-102

Stereoisomer composition of the chiral UV filter

4-methylbenzylidene camphor in environmental

samples

Buser H R, Müller M D, Balmer M E, Poiger T,

Buerge I J

Switzerland

Marine & Freshwater Biology , Water Resources ,

Hydrology , Toxicology

4-Methylbenzylidene camphor (4-MBC) is an important

organic UV filter used in many personal care

products such as sunscreens and cosmetics. After

use, 4-MBC may enter the aquatic environment due

to its release from skin during recreational activities

(swimming, bathing) and from personal hygiene measures

(washing, laundering of cloths) via wastewater

treatment plants (WWTPs). In fact, 4-MBC has been

detected in wastewater, in surface waters, and even

in fish. 4-MBC can exist as distinct cis-(Z) and trans-

(E)-isomers, both of which are chiral. Despite the fact

that stereoisomers often show a different biological

behavior, the stereochemistry of 4-MBC has hardly

ever been considered in environmental or biological

studies. In this study, enantioselective gas chromatographymass

spectrometry (GC-MS) was used to determine

the stereoisomer composition of 4-MBC. For

stereoisomer assignment, the pure enantiomers of

(E)-4-MBC were synthesized from (+)- and (-)-camphor.

The photochemical isomerization (sunlight) of

these (E)-isomers to the corresponding (2)-isomers

eventually allowed the configurational assignment of

all four stereoisomers of 4-MBC. In a technical material

and in a major brand sun lotion, 4-MBC was shown

to consist entirely (> 99%) of (E)-isomers and to be

racemic (R/S, 1.00 +/- 0.02). Wastewater showed the

presence of both (E)- and (Z)-4-MBC with a clear excess

of (E)-isomers (E > 2). Untreated wastewater

showed a nearly racemic composition (R/S= 0.95-

1.09), suggesting that most if not all commercial 4-

MBC is racemic. Treated wastewater indicated some

excess of (R)- or (S)-stereoisomers (R/S, 0.89-1.17),

likely as a result of some enantioselective (bio) degradation

in WWTPs. Residues of 4-MBC in lakes and in

a river with inputs from WWTPs and/or recreational

activities consisted mainly of (E)-4-MBC and, with exception

of one lake (Greifensee), showed a small

enantiomer excess (R/S, 1.04-1.16). In Greifensee, 4-

MBC showed a higher enantiomer excess (R/S, 1.70-

1.83), probably as a result of more extensive biotic

degradation in this lake. The analysis of 4-MBC in a

small number of fish from these lakes indicated

residues with nearly racemic compositions or a moderate

enantiomer excess (R/S, similar to 1.0-1.2) in

roach (Rutilus rutilus), whereas in perch (Perca fluviatilis)

a much higher enantiomer excess (R/S, similar

to 5) was observed. The data indicate that the

stereoisomer composition of 4-MBC in environmental

samples is not only a function of initial product com-

1.5 Oceans and Freshwater Systems

position but is also modified by enantioselective processes

in lakes and biota (fish).

Environmental Science Technology, 2005, V39, N9,

MAY 1, pp 3013-3019

05.3-103

Special section - Mountain waters: climatic and

hydrological sensitivity

Corripio J G, de Jong C

Switzerland, Germany

Meteorology & Atmospheric Sciences , Hydrology

Hydrology and Earth System Sciences, 2004, V8, N6,

DEC, p 1015

05.3-104

In vitro assessment of modes of toxic action of

pharmaceuticals in aquatic life

Escher B I, Bramaz N, Eggen R I L, Richter M

Switzerland

Toxicology , Marine & Freshwater Biology , Water

Resources

An ecotoxicological test battery based on a mode-ofaction

approach was designed and applied to the hazard

identification and classification of modes of action

of six pharmaceuticals (carbamazepine, diclofenac,

ethinyl estradiol, ibuprofen, propranolol, and sulfamethoxazole).

The rationale behind the design of

the battery was to cover the relevant interactions that

a compound may have with biological targets. It is

thus not comprehensive but contains representative

examples of each category of mode of toxic action including

nonspecific, specific, and reactive toxicity. The

test battery consists of one test system for nonspecific

toxicity (baseline toxicity or narcosis), two test systems

for specific effects, and two test systems for reactive

toxicity. The baseline toxicity was quantified

with the Kinspec test, which detects membrane leakage

via measurements of membrane potential. This

test system may also be used to detect the specific

effects on energy transduction, although this was not

relevant to any compound investigated in this study.

As examples of specific receptor-mediated toxicity, we

chose the yeast estrogen screen (YES) as a specific

test for estrogenicity, and the inhibition of chlorophyll

fluorescence in algae to assess specific effects on

photosynthesis. Reactive modes of action were assessed

indirectly by measuring the relevance of cellular

defense systems. Differences in growth inhibition

curves between a mutant of Escherichia coli that

could not synthesize glutathione and its parent strain

indicate the relevance of conjugation with glutathione

as a defense mechanism, which is an indirect indicator

of protein damage. DNA damage was assessed by

Global Change Abstracts – The Swiss Contribution 55


comparing the growth inhibition in a strain that lacks

various DNA repair systems with that in its competent

parent strain. Most compounds acted merely as baseline

toxicants in all test systems. As expected,

ethinylestradiol was the only compound showing estrogenic

activity. Propranolol was baseline- toxic in all

test systems except for the photosynthesis inhibition

assay, where it surprisingly showed a 100-fold excess

toxicity over the predicted baseline effect. The exact

mode of toxic action could not be confirmed, but additional

chlorophyll fluorescence induction experiments

excluded the possibility of direct interference with

photosynthesis through photosystem 11 inhibition.

Mixture experiments were performed as a diagnostic

tool to analyze the mode of toxic action. Compounds

with the same mode of toxic action showed the expected

concentration addition. In the photosynthesis

inhibition assay, agreement between experimental results

and prediction was best for two-stage predictions

considering the assigned modes of action. In a

two-stage prediction, concentration addition was used

as a model to predict the mixture effect of the baseline

toxicants followed by their independent action as

a single component combined with the specifically

acting compound propranolol and the reference compound

diuron. A comparison with acute toxicity data

for algae, daphnia, and fish showed generally good

agreement for the nonspecifically acting compounds

but also that the proposed test battery offered better

diagnostic value in the case of the specifically acting

compounds.

Environmental Science Technology, 2005, V39, N9,

MAY 1, pp 3090-3100

05.3-105

An environmentally relevant concentration of

estrogen induces arrest of male gonad

development in zebrafish, Danio rerio

Fenske M, Maack G, Schafers C, Segner H

Germany, Switzerland

Fisheries , Marine & Freshwater Biology , Toxicology ,

Zoology , Water Resources , Hydrology

The aim of the present study was to elucidate how full

life-cycle exposure to estrogens impacts zebrafish development

and reproduction, compared to partial lifecycle

exposure only, and whether the estrogen-induced

effects in zebrafish are reversible or irreversible.

Zebrafish were exposed in a flow-through

system to an environmentally relevant concentration

(3 ng/L) of the synthetic estrogen 17 alpha- ethinylestradiol

(EE2) either from fertilization until the allovary

stage of gonad development (i.e., 42 d postfertilization

(DPF) in our experiment) or from fertilization

until the reproductive stage (i.e., 118 DPF). Reversibility

of the estrogen -induced effects was assessed

after 58 d of depuration in EE2-free water until 176

DPE Early life exposure led to a lasting induction of

56

Global Change Abstracts – The Swiss Contribution

1.5 OCEANS AND FRESHWATER SYSTEMS

plasma vitellogenin (VTG) in adult females but altered

neither the sex ratio nor the reproductive capabilities.

Full lifecycle exposure resulted in elevated VTG concentrations

and caused gonadal feminization in 100%

of exposed fish and thus inhibited reproduction. Two

types of ovaries were observed in continuously exposed

adult fish, immature ovaries with primary

growth stage oocytes only and mature ovaries containing

the full range of all oocyte maturation stages.

Fish with immature ovaries had plasma VTG levels

like control males, while fish with mature ovaries had

female-like VTG levels. The effects of full life cycle exposure

were at least partly reversible, and 26% of fish

of the previous all-female cohort developed fully differentiated

testes. These findings suggest that continuous

estrogen exposure had arrested the developmental

transition of the gonads of genetic males from

the early all-ovary stage to functional testes. After the

exposure had ceased, however, these males apparently

were able to accomplish testicular differentiation.

Environmental Toxicology and Chemistry, 2005, V24,

N5, MAY, pp 1088-1098

05.3-106

Depositional history of organic contaminants in

Narragansett Bay, Rhode Island, USA

Hartmann P C, Quinn J G, Cairns R W, King J W

Switzerland, USA

Toxicology , Marine & Freshwater Biology, Limnology,

Hydrology

Sediment cores were taken at three locations in Narragansett

Bay, Rhode Island, USA in 1997 and analyzed

for a variety of organic contaminants including

polycyclic aromatic hydrocarbons (PAHs), polychlorinated

biphenyls (PCBs), chlordanes, linear alkyl benzenes

(LABs), benzotriazoles (BZTs) and dichlorodiphenyltrichloroethanes

(DDTs) and metabolites. The

distributions of these chemicals at Apponaug Cove

and in the Seekonk River indicate that there was a

disturbance in the depositional environment relative to

cores collected at these locations in 1986 demonstrating

the potential for buried contaminants to be remobilized

in the environment even after a period of burial.

Sharp breaks in the concentration of several organic

markers with known dates of introduction were successfully

used to determine the sedimentation rate at

Quonset Point. Both the Quonset Point and Seekonk

River cores had subsurface maximums for DDTs,

PCBs, PAHs and BZTs, which are consistent with expected

inputs to the environment. The Apponaug

Cove core showed an increase of most contaminants

at the surface indicating a recent event in which more

contaminated sediments were deposited at that location.

Marine Pollution Bulletin, 2005, V50, N4, APR,

pp 388-395


05.3-107

Climatic change and the effect on hydrology and

water management in the Rhine basin

Krahe P, Buiteveld H, Pfister L, Ritz C, Sprokkereef E

Germany, Netherlands, Luxembourg, Switzerland

Hydrology , Water Resources , International Relations

There has been a marked increase in recent years in

the resources dedicated to investigating the problems

arising from climate change with respect to hydrology

and to some extent to water resource management.

Many of these studies are concentrated on the river

Rhine basin. In order to review the actual state of scientific

findings a workshop, organised by the International

Commission for the Hydrology of the Rhine

(CHR), was held on 24 and 25 June 2003. The invited

experts discussed the following topics: observed variability

in climatic and hydrological data, the development

and interpretation of climate scenarios, and assessment

of changes in the discharge regimes and

the occurrence of hydrological extremes. Based on

the workshop the question of whether or not current

knowledge and procedural strategies can be used as

a basis for future water management was evaluated

by an expert group of the CHR. In this paper the process

of decision-making with regard to flood management

is analysed. Hints are given to convince the decision-makers

to take into account the impacts of climate

change in water resources management. The

special challenges arising in international river basins

are discussed.

Water Science and Technology, 2005, V51, N5,

pp 23-30

05.3-108

Stochastic modeling of diffuse pesticide losses

from a small agricultural catchment

Lindahl A M L, Kreuger J, Stenstrom J, Gardenas A I,

Alavi G, Roulier S, Jarvis N J

Sweden, Switzerland

Agriculture, Soil Sciences , Hydrology , Modelling ,

Toxicology

The objective of this study was to identify the main

sources of variation in pesticide losses at field and

catchment scales using the dual permeability model

MACRO. Stochastic simulations of the leaching of the

herbicide MCPA (4-chloro-2-methylphenoxyacetic

acid) were compared with seven years of measured

concentrations in a stream draining a small agricultural

catchment and one year of measured concentrations

at the outlet of a field located within the catchment.

MACRO was parameterized from measured

probability distributions accounting for spatial variability

of soil properties and local pedotransfer functions

derived from information gathered in field- and catchment-scale

soil surveys. At the field scale, a single deterministic

simulation using the means of the input

1.5 OCEANS AND FRESHWATER SYSTEMS

distributions was also performed. The deterministic

run failed to reproduce the summer outflows when

most leaching occurred, and greatly underestimated

pesticide leaching. In contrast, the stochastic simulations

successfully predicted the hydrologic response

of the field and catchment and there was a good resemblance

between the simulations and measured

MCPA concentrations at the field outlet. At the catchment

scale, the stochastic approach underestimated

the concentrations of MCPA in the stream, probably

mostly due to point sources, but perhaps also because

the distributions used for the input variables did

not accurately reflect conditions in the catchment.

Sensitivity analyses showed that the most important

factors affecting MACRO modeled diffuse MCPA losses

from this catchment were soil properties controlling

macropore flow, precipitation following application,

and organic carbon content.

Journal of Environmental Quality, 2005, V34, N4,

JUL-AUG, pp 1174-1185

05.3-109

Altitude-dependent differences in the primary

physical response of mountain lakes to climatic

forcing

Livinstone D M, Lotter A F, Kettle H

Switzerland, Netherlands, Scotland

Meteorology & Atmospheric Sciences , Hydrology ,

Limnology

Simultaneous hourly measurements of lake surface

water temperature (LSWT) during summer and early

autumn 2000 in 29 lakes in the Swiss Alps revealed

the presence of two altitudinally distinct thermal

regimes. The threshold separating the low-altitude

from the high- altitude regime was located at similar to

2,000 m above sea level during early summer 2000

but rose as summer progressed. Within the low-altitude

regime, LSWTs are strongly related to altitude

and surface air temperature. On crossing the threshold

to the high- altitude regime, the LSWT lapse rate

increases sharply, but the relationship of LSWT to

both altitude and air temperature weakens considerably.

A difference in the response of low-altitude and

high- altitude mountain lakes to climatic forcing in early

summer may have implications for climate change

studies in which mountain lakes are employed either

for paleoclimate reconstructions or as sensitive indicators

of current climate change. Any long-term temporal

change in the threshold altitude would imply that

lakes close to the threshold may not always have

been located in the same thermal regime, with consequences

for paleolimnological climate reconstructions.

Predictions of the effects of future climate warming on

high-altitude mountain lakes may have to take into account

the possibility of a concomitant rise in the

threshold altitude.

Limnology and Oceanography, 2005, V50, N4, JUL,

pp 1313-1325

Global Change Abstracts – The Swiss Contribution 57


05.3-110

Ocean gyres and abrupt change in the

thermohaline circulation: A conceptual analysis

Longworth H, Marotzke J, Stocker T F

England, Germany, Switzerland

Meteorology & Atmospheric Sciences , Modelling ,

Oceanography

The implications are investigated of representing

ocean gyre circulations by a diffusion term in the

Stommel and Rooth box models of the thermohaline

circulation (THC) in one and two hemispheres, respectively.

The approach includes mostly analytical

solution and study of the bifurcation structure, but also

numerical integration and feedback analysis. Sufficient

diffusion (gyre strength) eliminates multiple equilibria

from either model, highlighting the need for accurate

gyre circulation strength in general circulation

models (GCMs) when considering the potential for

abrupt climate change associated with THC shutdown.

With diffusion, steady-state flow strength in the

Rooth model depends on freshwater forcing (i.e., implied

atmospheric water vapor transport) in both hemispheres,

not only on that in the upwelling hemisphere,

as in the nondiffusive case. With asymmetric freshwater

forcing, two solutions (strong stable and weak unstable)

are found with sinking in the hemisphere with

stronger forcing and one solution with sinking in the

other hemisphere. Under increased freshwater forcing

the two solutions in the hemisphere with stronger forcing

meet in a saddle-node bifurcation (if diffusion is

sufficiently strong to prevent a suberitical Hopf bifurcation

first), followed by flow reversal. Thus, the bifurcation

structure with respect to freshwater forcing of

the diffusive Rooth model of two-hemisphere THC is

similar to that of the Stommel model of single-hemisphere

THC, albeit with a very different dynamical interpretation.

Gyre circulations stabilize high-latitude

sinking in the Stommel model. In the Rooth model,

gyre circulations only stabilize high-latitude sinking if

the freshwater forcing is weaker in the sinking hemisphere

than in the upwelling hemisphere, by an

amount that increases with diffusion. The values of

diffusion and freshwater forcing at which qualitative

change in behavior occurs correspond to the range of

the values used in and obtained with GCMs, suggesting

that this analysis can provide a conceptual foundation

for analyzing the stability of the interhemispheric

THC, and also for the potential of the Atlantic THC

to undergo abrupt change.

Journal of Climate, 2005, V18, N13, JUL 1,

pp 2403-2416

58

Global Change Abstracts – The Swiss Contribution

1.5 OCEANS AND FRESHWATER SYSTEMS

05.3-111

Use of slow filtration columns to assess oxygen

respiration, consumption of dissolved organic

carbon, nitrogen transformations. and microbial

parameters in hyporheic sediments

Mermillod Blondin F, Mauclaire L, Montuelle B

France, Switzerland

Geochemistry & Geophysics , Limnology , Marine &

Freshwater Biology

Biogeochemical processes mediated by microorganisms

in river sediments (hyporheic sediments) play a

key role in river metabolism. Because biogeochemical

reactions in the hyporheic zone are often limited to

the top few decimetres of sediments below the watersediment

interface, slow filtration columns were used

in the present study to quantify biogeochemical processes

(uptakes of O-2, DOC, and nitrate) and the associated

microbial compartment (biomass, respiratory

activity, and hydrolytic activity) at a centimetre scale in

heterogeneous (gravel and sand) sediments. The results

indicated that slow filtration columns recreated

properly the aerobic-anaerobic gradient classically observed

in the hyporheic zone. O-2 and NO3- consumptions

(256 +/- 13 µg of O-2 per hour and 14.6 +/-

6.1 µg of N-NO3- per hour) measured in columns were

in the range of values measured in different river sediments.

Slow filtration columns also reproduced the

high heterogeneity of the hyporheic zone with the

presence of anaerobic pockets in sediments where

denitrification and fermentation processes occurred.

The respiratory and hydrolytic activities of bacteria

were strongly linked with the O-2 consumption in the

experimental system, highlighting the dominance of

aerobic processes in our river sediments. In comparison

with these activities, the bacterial biomass (protein

content) integrated both aerobic and anaerobic

processes and could be used as a global microbial indicator

in our system. Finally, slow filtration columns

are an appropriate tool to quantify in situ rates of biogeochemical

processes and to determine the relationship

between the microbial compartment and the

physico-chemical environment in coarse river sediments.

Water Research, 2005, V39, N9, MAY, pp 1687-1698


05.3-112

Comet assay with the fish cell line rainbow trout

gonad-2 for in vitro genotoxicity testing of

xenobiotics and surface waters

Nehls S, Segner H

Switzerland, Germany

Water Resources , Marine & Freshwater Biology ,

Toxicology , Zoology , Fisheries

The present study examines the potential of the

comet assay using the rainbow trout gonad cell line-2

(RTG-2) as an in vitro indicator test for genotoxicity

assessment of aquatic contaminants and native surface

waters. Initially, the comet assay protocol was

adapted to the RTG-2 cell line. An exposure period of

2 h was found to be optimal, because DNA damage

decreased when exposure was prolonged. Then, the

sensitivity of the comet assay with RTG-2 cells toward

six genotoxic reference substances was evaluated.

The lowest-observed- effect concentration values for

the directly acting genotoxins, 4- nitroquinoline-N-oxide

and N-methyl-N'-nitro-N-nitrosoguanidine, were in

the low nanomolar range. The RTG-2 test system

clearly was less sensitive for the indirectly acting

genotoxins benzo(a)pyrene, nitrofurantoin, 2-acetylaminofluorene,

and dimethylnitrosamine, despite the

presence of xenobiotic metabolic capacities in RTG-2

cells. The two effect endpoints used, tail length (TL)

and tail moment (TM), did not differ with respect to

sensitivity, but the linearity of the concentration-response

curve was better with TM than with TL. The

overall reproducibility of the assay results was good.

Finally, the applicability of the comet assay with RTG-

2 cells for genotoxicity screening of native surface water

samples was studied. The assay tolerated the use

of nonsterile water samples and was able to detect

genotoxic potentials in native water samples; that is,

extraction and concentration of the samples were not

needed. The results of the present study indicate the

suitability of the comet assay with the fish cell line,

RTG-2, as in vitro screen for detecting genotoxic potencies

of xenobiotics and environmental samples.

Environmental Toxicology and Chemistry, 2005, V24,

N8, AUG, pp 2078-2087

05.3-113

A Bayesian combination method of flood models:

Principles and application results

Niggli M, Musy A

Switzerland

Hydrology , Modelling

Instead of attempting to find the "best" flood estimation

method, we propose a Bayesian methodology

that combines several existing models. A common

problem with flood estimation is that no single model

performs better than the others for all types of catchments

and under all circumstances. Moreover, if complementary,

each model captures only a part of the in-

1.5 OCEANS AND FRESHWATER SYSTEMS

formation available for prediction. A combination

seems therefore a logical approach. In this paper, we

propose a Bayesian solution: a prior density of the

"true" flood quantile for a given return period is updated

using successive likelihood functions, involving at

each step a different flood estimation model. The implementation

is straightforward in the normal-linear

case, where both the prior density and the likelihood

functions are normally distributed and where the relationship

between the model's estimates and the "true"

values of the flood quantile is linear. This can be generally

achieved with an appropriate transformation of

the flood quantiles. The parameters of each likelihood

function are either estimated judgmentally or by linear

regression, using a joint sample of observed quantiles

and the corresponding model estimation. Under the

above-mentioned assumptions, the posterior distribution

is normal with expectancy being a linear combination

of the prior estimate and the different models'

estimates. In order to show the potential of the combination

method, an example with three different flood

estimation methods for Western Switzerland is presented.

The resulting combination is an interesting

tool giving preference to different models, depending

on the catchment size and on the availability of flood

data at the site of interest. Moreover, it provides a posterior

variance of the quantity of interest that is as small

or smaller than the one of the "best" single model.

Agricultural Water Management, 2005, V77, N1-3,

AUG 22, pp 110-127

05.3-114

Effectsd of riparian arthropod predation on the

biomass and abundance of aquatic insect

emergence

Paetzold A, Tockner K

Switzerland

Biodiversity , Zoology , Marine & Freshwater Biology

Adult aquatic insects are important energy subsidies

for terrestrial predators, but the effects of terrestrial

predators on emerged aquatic insects have been

widely neglected. We compared emergence of aquatic

insects from predator-free exclosures and open

cages to test the hypothesis that riparian arthropod

predators can reduce the abundances of emerged

aquatic insects. We used emergence traps over the

aquatic and terrestrial sides of the shoreline to collect

insects that emerged from the water or crawled onto

land to emerge. The abundances and taxonomic composition

of emerged aquatic insects and riparian

arthropod predators changed seasonally. Riparian

arthropods consumed 45% of emerged aquatic insect

biomass from terrestrial traps in spring and 45% from

aquatic traps in summer. The dominant riparian

predator at the time of emergence determined the

specific predation effect. Stoneflies that emerged into

terrestrial traps were significantly reduced when

ground beetles were the most abundant predators;

caddisflies that emerged into aquatic traps were sig-

Global Change Abstracts – The Swiss Contribution 59


nificantly reduced when spiders were the most abundant

predators. Thus, taxon-specific predation by riparian

arthropods can affect the taxonomic composition

of emerged aquatic insects.

Journal of the North American Benthological Society,

2005, V24, N2, JUN, pp 395-402

05.3-115

Effects of 12 years' operation of a sewage treatment

plant on trace metal occurrence within a

Mediterranean commercial sponge (Spongia

officinalis, Demospongiae)

Perez T, Longet D, Schembri T, Rebouillon P, Vacelet J

France, Switzerland

Plant Sciences , Marine & Freshwater Biology ,

Toxicology

The present field study uses Spongia officinalis for assessing

trace metals occurrence in time and space

within Mediterranean rocky communities. Nine sites

were selected in the Marseille area for studying spatial

trends in 12 metal concentrations. Long term

changes in 8 metal concentrations were assessed at

sites that had been sampled before and 12 years after

the opening of a treatment plant. Spongia officinalis

highly concentrated all the trace metal surveyed excepted

Hg and Cd. The overall contamination level

registered provided a classification of the study sites

which is congruent with that given by other studies on

pollutant accumulation in neighbouring sandy-bottoms

or benthic assemblages. Among the metals studied,

Fe, Pb, Cr are those that best highlighted a pollution

gradient. In the present study, only Cd concentration

did not vary in space. Except for Ni, all pollutant concentrations

clearly decreased between 1984 and

1999. This very impressive decrease in heavy metal

concentrations within the Marseille area represents an

indisputable evidence of the improvement of the seawater

quality resulting from 12 years' operation of the

Marseille sewage plant. Moreover, the significant decrease

also recorded in the reference population at

Port-Cros might reflect an overall improvement in the

seawater quality of the NW Mediterranean.

Marine Pollution Bulletin, 2005, V50, N3, MAR,

pp 301-309

05.3-116

Phosphorus retention in small constructed

wetlands treating agricultural drainage water

Reinhardt M, Gachter R, Wehrli B, Müller B

Switzerland

Modelling , Agriculture, Soil Sciences , Limnology ,

Engineering , Hydrology , Geochemistry &

Geophysics , Plant Sciences

The construction of artificial wetlands has become a

measure increasingly applied to reduce nonpoint-

60

Global Change Abstracts – The Swiss Contribution

1.5 OCEANS AND FRESHWATER SYSTEMS

source (NPS) pollution and to contribute to the

restoration of eutrophic lakes and coastal waters. In a

2-yr study monitoring fluxes of particulate and dissolved

phosphorus (P) in a small artificial wetland for

the treatment of agricultural drainage water in Central

Switzerland, water residence time was identified as

the main factor controlling P retention in the system.

Since most of the annual P load (62% as dissolved

reactive phosphorus, DRP) was related to high discharge

events, it was not average but minimum water

residence time during flood events that determined

the wetland's P retention. In agreement with a continuous

stirred tank reactor (CSTR) model, our investigations

suggest a minimum water residence time of 7

d to retain at least 50% of the bioavailable P. The investigated

wetland retained only 2% of the bioavailable

P, since the water residence time was shorter

than 7 d during 61% of time in both years. Settling of

phytoplankton rather than DRP uptake into phytoplankton

limited the retention of bioavailable P. The

overall retention efficiency of 23% total phosphorus

(TP), corresponding to a surface related retention of

1.1 g P m(-2) yr(-1), was due to the efficient trapping

of pedogenic particles.

Journal of Environmental Quality, 2005, V34, N4,

JUL-AUG, pp 1251-1259

05.3-117

Simple determination of the herbicide

napropamide in water and soil samples by room

temperature phosphorescence

Salinas Castillo A, Fernandez Sanchez J F, Segura

Carretero A, Fernandez Gutierrez A

Spain, Switzerland

Agriculture, Soil Sciences , Geochemistry &

Geophysics , Hydrology , Toxicology

A new, simple, rapid and selective phosphorimetric

method for determining napropamide is proposed

which demonstrates the applicability of heavy-atominduced

room-temperature phosphorescence for analyzing

pesticides in real samples. The phosphorescence

signals are a consequence of intermolecular

protection and are found exclusively with analytes in

the presence of heavy atom salts. Sodium sulfite was

used as an oxygen scavenger to minimize room-temperature

phosphorescence quenching. The determination

was performed in 1 m potassium iodide and 6

rum sodium sulfite at 20 degrees C. The phosphorescence

intensity was measured at 520 nm with excitation

at 290 nm. Phosphorescence was easily developed,

with a linear relation to concentration between

3.2 and 600.0 ng ml(-1) and a detection limit of 3.2 ng

ml(-1). The method has been successfully applied to

the analysis of napropamide in water and soil samples

and an exhaustive interference study was also

carried out to display the selectivity of the proposed

method.

Pest Management Science, 2005, V61, N8, AUG,

pp 816-820


05.3-118

Weak mixing in Lake Kivu: New insights indicate

increasing risk of uncontrolled gas eruption

Schmid M, Halbwachs M, Wehrli B, Wüest A

Switzerland, France

Limnology , Marine & Freshwater Biology, Hydrology ,

Geochemistry & Geophysics

The deep waters of the East African Rift Lake Kivu

contain large amounts of dissolved carbon dioxide

and methane. The release of a fraction of these gases,

which could be triggered by a magma eruption

within the lake, would have catastrophic consequences

for the two million people living on its shore.

Up to now the safety assessment of the lake was

based on the assumption that the gas concentrations

in the deep waters are in a steady state with a residence

time of 400 years. Turbulent transport was regarded

as the main pathway of vertical exchange. Recent

measurements and the analysis of the vertical

transport processes in the lake radically change this

evaluation. The vertical turbulent exchange is negligible,

as documented by a spectacular set of several

hundred double-diffusive layers. Gases are mainly

transported out of the deep zones by a slow upwelling

with a residence time of 800-1000 years. Our results

indicate that the methane production within the sediment

has recently increased, leading to a gas accumulation

in the deep waters and consequently decreasing

the heat input needed to trigger a devastating

gas release. With the estimated current CH4 production,

the gas concentrations could approach saturation

within this century.

Geochemistry Geophysics Geosystems, 2005, V6,

JUL 26, ARTN: Q07009

05.3-119

Factors controlling delta C-13 values of sedimentary

carbon in hypertrophic Baldeggersee,

Switzerland, and implications for interpreting

isotope excursions in lake sedimentary records

Teranes J L, Bernasconi S M

USA, Switzerland

Limnology , Hydrology , Marine & Freshwater Biology

We use stable carbon isotope values (delta(13)C) in

sedimented organic matter and carbonate as proxy indicators

of productivity changes in a highly eutrophic

to hypertrophic lake. Stable isotope data from a seasonally

sampled sediment core recovered from

Baldeggersee, Switzerland were compared with direct

and inferred total phosphorus (P) concentrations. Carbon

isotope values of sedimentary organic matter

(delta(13)C(org)) in both seasonal varves and over

the past 100 yr are not linearly related to total P concentrations,

nor do they mirror observed trends in carbonate

isotope values (delta(13)C(CaCO3)). Baldeg-

1.5 OCEANS AND FRESHWATER SYSTEMS

gersee delta(13)C(org) values are influenced by both

variations in the relative inputs of eukaryotic biomass,

which becomes enriched in C-13 with increasing primary

productivity, and the contribution of microbial

biomass produced in the expanding anoxic bottom

waters, which is typically very depleted in C-13. We

also examined the fractionation within the organic

matter-CO2-CaCO3 system, calculated as epsilon(total

organic carbor(TOC)) = 10(3){((delta(13)C(CaCO3) +

1,000)/(delta(13)C(org) + 1,000)) - 1}. Thresholds

within the measured epsilon(TOC) values represent

Baldeggersee trophic status more accurately than

delta(13)C (org) or delta(13)C(CaCO3) values alone.

In alkaline lakes with endogenic carbonate precipitates,

STOC values can facilitate accurate interpretation

of values and trends in organic carbon isotope

data, and can help to better assess trophic history

and lake remediation efforts in lake systems that have

been heavily affected by cultural eutrophication.

Limnology and Oceanography, 2005, V50, N3, MAY,

pp 914-922

05.3-120

Planform channel dynamics of the lower Colorado

River: 1976-2000

Tiegs S D, Pohl M

Switzerland, USA

Biodiversity , Hydrology , Modelling

In the past two decades, major flood events have occurred

on the lower Colorado River, a dramatic shift

from the low flows and moderate floods associated

with prior decades of river regulation. This study uses

repeat aerial photography and Geographic Information

System analysis to examine the planform channel

response of the upper Colorado River delta (limitrophe

reach) to this recently altered hydrology. Results

indicate that channel contraction has been the dominant

planform process in recent decades, but periodic

floods resulted in channel expansion (1981-1988;

1997-2000) or likely reduced the channel contraction

measured between successive aerial photographs

(1976-1981; 1988-1994). Sinuosity adjustments were

limited during the timeframe of the study (range: 1.31

to 1.38), but the channel did respond with large adjustments

in channel width (range: 44 in to 355 in)

and changes in total mid-channel bar area (range: 0

to 52.3 ha). A channel probability model developed for

this study provides a raster image of the channel

changes and depicts areas modified to varying degrees

by flood flows. This historical study provides insight

into how floods affect the channel system that

provides the foundation for aquatic and riparian biodiversity.

This issue is of increasing relevance given

growing international interest in rehabilitating the riparian

and aquatic ecosystems of the Colorado River

delta through intentional flood flows.

Geomorphology, 2005, V69, N1-4, JUL, pp 14-27

Global Change Abstracts – The Swiss Contribution 61


05.3-121

The hydrological significance of mountains:

from regional to global scale

Viviroli D, Weingartner R

Switzerland

Hydrology , Water Resources , Geomorphology

Mountain regions supply a large share of the world's

population with fresh water. Quantification of the hydrological

significance of mountains, however, is subject

to great uncertainty. Instead Of focusing on global

averages in advance, the present analysis follows a

catchment-based approach using discharge data provided

by the Global Runoff Data Centre (GRDC). The

River Rhine originating in the European Alps is chosen

as a first study area, revealing the hydrological

relationship between mountainous and lowland regions

in a well -documented area. Following the findings

from this analysis, different aspects of runoff

characteristics for a total of 22 case- study river

basins world-wide have been investigated and compared,

for a global view. The view has been extended

through aspects of' climate and human use of mountain

runoff. The particular hydrological characteristics

of mountain areas are characterised by disproportionately

large discharges. In humid areas, mountains

supply up to 20-50% of total discharge while in arid

areas, mountains contribute from 50-90% of total discharge,

with extremes of over 95%. The overall assessment

of the hydrological significance of mountain

areas reveals that the world's major 'water towers' are

found in arid or semi-arid zones where they provide

essential fresh water for a significant proportion of a

quickly growing global Population.

Hydrology and Earth System Sciences, 2004, V8, N6,

DEC, pp 1016-1029

05.3-122

Removal of heavy metals from mine waters by

natural zeolites

Wingenfelder U, Hansen C, Furrer G, Schulin R

Switzerland, Germany

Hydrology , Geochemistry & Geophysics , Toxicology

In this study, we investigated the removal of Fe, Pb,

Cd, and Zn from synthetic mine waters by a natural

zeolite. The emphasis was given to the zeolite's behavior

toward a few cations in competition with each

other. Pb was removed efficiently from neutral as well

as from acidic solutions, whereas the uptake of Zn

and Cd decreased with low pH and high iron concentrations.

With increasing Ca concentrations in solution,

elimination of Zn and Cd became poorer while

removal of Pb remained virtually unchanged. The zeolite

was stable in acidic solutions. Disintegration was

only observed below pH 2.0. Forward and back-titration

of synthetic acidic mine water were carried out in

the presence and absence of zoolite to simulate the

effects of a pH increase by addition of neutralizing

62

Global Change Abstracts – The Swiss Contribution

1.5 OCEANS AND FRESHWATER SYSTEMS

agents and a re-acidification which can be caused by

subsequent mixing with acidic water. The pH increase

during neutralization causes precipitation of hydrous

ferric oxides and decreased dissolved metal concentrations.

Zeolite addition further diminished Pb concentrations

but did not have an effect on Zn and Cd

concentrations in solution. During re-acidification of

the solution, remobilization of Pb was weaker in the

presence than in the absence of zeolite. No substantial

differences were observed for Fe, Cd, and Zn immobilization.

The immobilization of the metals during

pH increase and the subsequent remobilization

caused by re-acidification can be well described by a

geochemical equilibrium speciation model that accounts

for metal complexation at hydrous ferric oxides,

for ion exchange on the zeolite surfaces, as well

as for dissolution and precipitation processes.

Environmental Science Technology, 2005, V39, N12,

JUN 15, pp 4606-4613

05.3-123

Carbon isotope fractionation in the reductive

dehalogenation of carbon tetrachloride at iron

(hydr)oxide and iron sulfide minerals

Zwank L, Elsner M, Aeberhard A, Schwarzenbach R P,

Haderlein S B

Germany, Switzerland

Geochemistry & Geophysics , Hydrology , Toxicology

Compound-specific isotope analysis (CSIA) is used

increasingly in contaminant hydrology in the attempt

to assess the nature as well as the extent of in situ

transformation reactions. Potentially, variations of stable

isotope ratios along a contaminant plume may be

used to quantify in situ degradation. In the present

study, the abiotic dehalogenation Of CCI4 by Fe(II)

present at the surface of different iron minerals has

been characterized in terms of the reaction rates and

carbon isotopic fractionation (delta(13)C) of carbon

tetrachloride (CCI4) as well as the yields and isotopic

signatures of chloroform (CHCI3), one of the main

transformation products. The abiotic reductive dehalogenation

Of CCI4 was associated with substantial carbon

isotopic enrichment effects. The observed enrichment

factors, c, correlated neither with the surf acenormalized

reaction rate constants nor with the type

of products formed but fell into two distinctly different

ranges for the two principal groups of minerals studied.

With iron (hydr)oxide minerals (goethite,

hematite, lepidocrocite, and magnetite) and with

siderite, the is an element of-values for CCI4 dehalogenation

were remarkably similar (-29 +/- 3 parts per

thousand). Because this value matches well with the

theoretical estimates for the cleavage of an aliphatic

C-Cl bond, we suggest that dissociative electron

transfer to CCI4 controls the reaction rates for this

group of iron minerals. Conversely, CCI4 transformation

by different preparations of the iron sulfide mackinawite

was accompanied by a significantly lower carbon

istotopic fractionation (is an element of = -15.9 +/-


1.5 OCEANS AND FRESHWATER SYSTEMS / 1.6 ENERGY BALANCE

0.3 parts per thousand), possibly due to the presence

of nonfractionating rate- determining steps or a significantly

different transition state structure of the reaction.

Isotopically sensitive branching of the reaction

pathways (i.e., the effect of different product distributions

on isotope fractionation Of CCI4) did not play a

significant role in our systems. The extensive data set

05.3-124

Comparison of modeled and observed cloud-free

longwave downward radiation over the Alps

Durr B, Philipona R, Schubiger F, Ohmura A

Switzerland

Modelling , Meteorology & Atmospheric Sciences

Differences between computed and observed cloudfree

longwave downward radiation (LDR) were examined

both for Payerne and six further radiation sites of

the Alpine Surface Radiation Budget (ASRB) network.

LDR was computed by the complex radiative transfer

model (RTM) MODTRAN v4.0 and by a simplified

RTM used in the numerical weather prediction model

"alpine model" (aLMo). MODTRAN computed LDR in

Payerne using sounding data and ASRB observed

LDR show an average difference of 1.5 W m(-2) ( +/-

3.5 W m(-2)), and -3.2 W m(-2) +/- 3.6 W m(-2)) for

night- and daytime respectively from 1996 to 2001.

Nighttime LDR is underestimated by the aLMo RTM in

the order of -20 W m(-2) compared to ASRB measurements

both at Payerne and at six further ASRB

sites. However LDR bias is strongly reduced in Payerne

during daytime. For comparison MODTRAN

computed LDR using aLMo forecasted atmospheric

profiles shows mean differences in the order of -3 W

m(-2) both for night- and daytime. Hence the comprehensive

radiation scheme used in aLMo is mainly responsible

for the substantial underestimation of cloudfree

LDR.

Meteorologische Zeitschrift, 2005, V14, N1, pp 47-55

05.3-125

On the determination of surface emissivity from

satellite observations

Mätzler C

Switzerland

Meteorology & Atmospheric Sciences , Remote

Sensing

Terrestrial brightness temperatures measured from

satellites have been used to determine the surface

emissivity. The results not only depend on surface

temperature and on atmospheric properties, but also

on the type of surface scattering. For otherwise identi-

1.6 Energy Balance

presented in this study opens new perspectives toward

an improved understanding of the factors that

determine reaction mechanisms and isotopic fractionation

of dehalogenation reactions by Fe(II) at iron

containing minerals.

Environmental Science Technology, 2005, V39, N15,

AUG 1, pp 5634-5641

cal conditions (same emissivity, same nonscattering

atmosphere), the radiation above the Lambertian surface

is larger than for a specular surface if the incidence

angle is smaller than about 55 degrees. The

opposite is true for larger angles. The effect leads to

overestimates of emissivity for observations especially

near nadir with the use of algorithms assuming

specular reflection. The problem may be solved by

the introduction of a specularity parameter to characterize

realistic surfaces by a combination of specular

and Lambert scattering. A simple solution lies in the

use of conically scanning radiometers at a constant

incidence angle near 55 degrees. Although the topic

applies to all ranges of thermal radiation, the present

discussion concentrates on the microwave spectrum

in the Rayleigh-jeans approximation.

Ieee Geoscience and Remote Sensing Letters, 2005,

V2, N2, APR, pp 160-163

05.3-126

Measurements and model calculations of the

solar shortwave fluxes in snow on Summit,

Greenland

Meirold Mautner I, Lehning M

Switzerland

Modelling , Meteorology & Atmospheric Sciences ,

Cryology / Glaciology

Solar shortwave (SW) radiation is a primary energy

source for the snow cover. Accurate measurements of

the radiation energy balance in snow are not yet available

over a broad spectral band. For accurate measurements

in snow, sources of errors have to be eliminated

such as the temperature dependence of some

sensors, investigating a disturbed snow cover or neglecting

the variation of the incoming radiation. The

objective of our investigation is to measure the spectral

SW energy balance in and above snow and to validate

a radiation transfer model against the data. In

July 2002 up- and downwelling fluxes at several

heights in snow were measured on Summit, Greenland,

with a spectrometer sensitive in the 340-1050

nm spectral band. Changing incoming solar radiation

was accounted for by using two sensor heads. The

resulting data are compared to the delta-Eddington

model of radiative transfer in combination with Mic

Global Change Abstracts – The Swiss Contribution 63


single-scattering calculations. Using as input the snow

data obtained by weekly snow profiles, a good agreement

between measured and modelled radiative fluxes

was obtained when increasing the absorption in

the snow grains which is justified by snow impurities.

In the near-infrared a disagreement between model

and measurements is obvious. This is most likely

caused by non-sphericity of the snow grains.

Annals of Glaciology Vol 38 2004, 2004, V38,

pp 279-284

05.3-127

Climate - How unusual is today's solar activity

Müscheler R, Joos F, Müller S A, Snowball I

USA, Switzerland, Sweden

Meteorology & Atmospheric Sciences

Nature, 2005, V436, N7050, JUL 28, pp E3-E4

05.3-128

Cloud effects on the radiation budget based on

ISCCP data (1991 to 1995)

Raschke E, Ohmura A, Rossow W B, Carlson B E,

Zhang Y C, Stubenrauch C, Kottek M, Wild M

Germany, Switzerland, USA, France, Austria

Meteorology & Atmospheric Sciences

Consistent and validated data sets of satellite-borne

radiances and of a large variety of products describing

the characteristics of terrestrial cloud and radiation

fields have been produced within the International

Satellite Cloud Climatology Project (ISCCP) covering

the years 1983 through to 2003. A subset (annual and

seasonal averages of the 5 year period 1991 to 1995)

is used in this paper to discuss in greater detail the effect

of clouds on the radiation fields at the upper and

lower boundary of the atmosphere and in particular on

the loss and gain (vertical divergence) of radiant energy

by the atmosphere itself. Although this subset covers

the effects of the Pinatubo eruption (June 1991)

and of the strong El Nino event in 1992-93, which indeed

caused 'anomalies in the average aerosol and

cloud fields in the tropics and subtropics'. However,

our regional averages of the radiation budget at the

top of the atmosphere and at ground over a period of

5 years should be within 2-5 W m(-2) of longer term

averages. We find very interesting spatial patterns in

the global distributions of all quantities, which can be

explained in part by various cloud field characteristics

and by the continental surface characteristics. Most

are known from similar studies with radiation budget

measurements. Possibly for the first time, we show

global fields of the vertical flux divergence of solar

and terrestrial radiation within the atmosphere and of

64

Global Change Abstracts – The Swiss Contribution

1.6 ENERGY BALANCE

the effects of clouds. Both polar regions, various portions

of China and the areas of persistent subtropical

maritime stratocumulus fields over the Pacific and Atlantic

Oceans and of cloud fields associated with the

intertropical convergence zone (ITCZ) offer specific

features for further analyses. This ISCCP data set

seems to underestimate the absorption of solar radiation

in the tropical and subtropical atmosphere by

about 10 to 20 W m(-2). There is a disagreement of

about 30 W m-2 in global averages of the gain and

loss of solar and terrestrial radiation in the atmosphere

between this and two other independent data

sets, which needs thorough investigation, since such

data are required to validate the radiation budgets

within circulation and climate models and for other climate

Studies. Such an assessment of radiation budget

data is now under way within the auspices of the

World Climate Research Programme.

International Journal of Climatology, 2005, V25, N8,

JUN 30, pp 1103-1125

05.3-129

Climate - How unusual is today's solar activity?

Reply

Solanki S K, Usoskin I G, Kromer B, Schüssler M,

Beer J

Germany, Finland, Switzerland

Meteorology & Atmospheric Sciences

Nature, 2005, V436, N7050, JUL 28, pp E4-E5

05.3-130

From dimming to brightening: Decadal changes in

solar radiation at Earth's surface

Wild M, Gilgen H, Roesch A, Ohmura A, Long C N,

Dutton E G, Forgan B, Kallis A, Russak V, Tsvetkov A

Switzerland, USA, Australia, Estonia, Russia

Meteorology & Atmospheric Sciences , Energy &

Fuels

Variations in solar radiation incident at Earth's surface

profoundly affect the human and terrestrial environment.

A decline in solar radiation at land surfaces has

become apparent in many observational records up to

1990, a phenomenon known as global dimming. Newly

available surface observations from 1990 to the

present, primarily from the Northern Hemisphere,

show that the dimming did not persist into the 1990s.

Instead, a widespread brightening has been observed

since the late 1980s. This reversal is reconcilable with

changes in cloudiness and atmospheric transmission

and may substantially affect surface climate, the hydrological

cycle, glaciers, and ecosystems.

Science, 2005, V308, N5723, MAY 6, pp 847-850


05.3-131

Comparing CO2 storage and advection conditions

at night at different carboeuroflux sites

Aubinet M, Berbigier P, Bernhofer C H, Cescatti A,

Feigenwinter C, Granier A, Grunwald T H,

Havrankova K, Heinesch B, Longdoz B, Marcolla B,

Montagnani L, Sedlak P

Belgium, France, Germany, Italy, Switzerland, Czech

Republic

Geochemistry & Geophysics , Meteorology &

Atmospheric Sciences , Geomorphology , Ecology

Anemometer and CO2 concentration data from temporary

campaigns performed at six CARBOEUROFLUX

forest sites were used to estimate the importance of

non-turbulent fluxes in nighttime conditions. While

storage was observed to be significant only during periods

of both low turbulence and low advection, the

advective fluxes strongly influence the nocturnal CO2

balance, with the exception of almost flat and highly

homogeneous sites. On the basis of the main factors

determining the onset of advective fluxes, the 'advection

velocity', which takes net radiation and local topography

into account, was introduced as a criterion

to characterise the conditions of storage enrichment/

depletion. Comparative analyses of the six sites

showed several common features of the advective

fluxes but also some substantial differences. In particular,

all sites where advection occurs show the onset

of a boundary layer characterised by a downslope

flow, negative vertical velocities and negative vertical

CO2 concentration gradients during nighttime. As a

consequence, vertical advection was observed to be

positive at all sites, which corresponds to a removal of

CO2 from the ecosystem. The main differences between

sites are the distance from the ridge, which influences

the boundary-layer depth, and the sign of the

mean horizontal CO2 concentration gradients, which

is probably determined by the source/sink distribution.

As a consequence, both positive and negative horizontal

advective fluxes (corresponding respectively to

CO2 removal from the ecosystem and to CO2 supply

to the ecosystem) were observed. Conclusive results

on the importance of non-turbulent components in the

mass balance require, however, further experimental

investigations at sites with different topographies,

slopes, different land covers, which would allow a

more comprehensive analysis of the processes underlying

the occurrence of advective fluxes. The

quantification of these processes would help to better

quantify nocturnal CO2 exchange rates.

Boundary Layer Meteorology, 2005, V116, N1, JUL,

pp 63-94

1.7 Coupled Systems and Cycles

05.3-132

Plant, soil microbial and soil inorganic nitrogen

responses to elevated CO2: a study in microcosms

of Holcus lanatus

Barnard R, Leadley P W, Lensi R, Barthes L

Switzerland, France

Plant Sciences , Agriculture, Soil Sciences ,

Geochemistry & Geophysics

The impact of elevated atmospheric CO2 concentrations

on the nitrogen cycle was evaluated in a 2month

experiment in monospecific grassland microcosms

(Holcus lanatus L.) grown on reconstituted

grassland soil. The responses of the N pools in the

plants, soil, and soil microbes were studied. The impact

of high CO, on key stages of the N cycle, especially

nitrification and denitrification processes, were

also measured. Our study showed a strong plant response

to high CO2: total biomass increased by 76%

(P < 0.001) and root length density increased by 77%

(P = 0.010). However, total plant N was not significantly

modified by high CO2, because the percent N in

the plant decreased by 40% (P < 0.001). We observed

a large decrease in soil NO3- concentration

under elevated CO2 (-50%; P = 0.002). Soil ammonium

concentrations were much less affected by CO2

enrichment, and only in resin bags (-8%, P = 0.019).

Soil nitrifying enzyme activity (NEA) had a tendency

to increase (+17%; P = 0.061) and denitrifying enzyme

activity (DEA) decreased (-12%; P = 0.013). We

found evidence of increased microbial N sink (microbial

N increased by 17%, P = 0.004). This and other

studies suggest that rising CO2 often reduces soil nitrate

concentrations, which may lead to decreased nitrate

leaching. Elevated CO2 led to environmental

conditions that were less favourable for denitrification

in our study.

Acta Oecologica International Journal of Ecology,

2005, V27, N3, MAY- JUN, pp 171-178

05.3-133

Ratio of the Greenland to global temperature

change: Comparison of observations and climate

modeling results

Chylek P, Lohmann U

USA, Canada, Switzerland

Meteorology & Atmospheric Sciences, Oceanography ,

Cryology / Glaciology , Modelling

Temperature changes over Greenland are of special

interest due to a possible melting of the Greenland Ice

Sheet and resulting sea level rise. General Circulation

Models ( GCMs) predict that the temperature changes

in Greenland should proceed at a faster rate than the

global temperature change. Until now there has been

no confirmation that Greenland's long- term tempera-

Global Change Abstracts – The Swiss Contribution 65


ture changes are related to the global warming and

that they proceed faster than the global temperature

change. Using double correlations between the

Greenland temperature records, North Atlantic Oscillation

( NAO) index and global temperature change

we find a region of Greenland that is not affected by

the NAO. Using this region as an indicator of Greenland's

temperature change that is related to global

warming, we find that the ratio of the Greenland to

global temperature change due to global warming is

2.2 in broad agreement with GCM predictions.

Geophysical Research Letters, 2005, V32, N14,

JUL 21, ARTN: L14705

05.3-134

Comparing estimates of persistence and

long-range transport potential among multimedia

models

Fenner K, Scheringer M, Macleod M, Matthies M,

Mckone T, Stroebe M, Beyer A, Bonnell M, Le Gall A C,

Klasmeier J, Mackay D, van de Meent D, Pennington D,

Scharenberg B, Suzuki N, Wania F

Switzerland, USA, Germany, Canada, France,

Netherlands, Italy, Japan

Modelling , Chemistry

Overall persistence (P-ov) and long-range transport

potential (LRTP) of organic chemicals are environmental

hazard metrics calculated with multimedia fate

and transport models. Since there are several models

of this type, it is important to know whether and how

different model designs (model geometry, selection of

compartments and processes, process descriptions)

affect the results for P., and LRTP. Using a set of 3175

hypothetical chemicals covering a broad range of partition

coefficients and degradation half-lives, we systematically

analyze the P-ov and LRTP results obtained

with nine multimedia models. We have developed

several methods that make it possible to visualize

the model results efficiently and to relate differences

in model results to mechanistic differences between

models. Rankings of the hypothetical chemicals

according to P-ov and LRTP are highly correlated

among models and are largely determined by the

chemical properties. Domains of chemical properties

in which model differences lead to different results are

identified, and guidance on model selection is provided

for model users.

Environmental Science Technology, 2005, V39, N7,

APR 1, pp 1932-1942

05.3-135

The role of vegetation and litter in the nitrogen

dynamics of riparian buffer zones in Europe

Hefting M M, Clement J C, Bienkowski P, Dowrick D,

Guenat C, Butturini A, Topa S, Pinay G,

Verhoeven J T A

66

Global Change Abstracts – The Swiss Contribution

1.7 COUPLED SYSTEMS AND CYCLES

Netherlands, France, Poland, England, Switzerland,

Spain, Romania

Plant Sciences , Geochemistry & Geophysics

Plant uptake and denitrification are considered to be

the most important processes responsible for N retention

and mitigation in riparian buffers. In many riparian

buffers, however, nutrients taken up by plants remain

in the system only temporarily and may be gradually

released by mineralization later. Still, plants increase

the residence time of nutrients considerably by reducing

their mobility. We investigated the importance of

plant N uptake and N immobilization in litter for N retention

in riparian buffers. Nitrogen uptake in vegetation

and N dynamics in litter were measured over a

two-year period in a range of forested and herbaceous

riparian buffers along a climatic gradient in Europe,

receiving different loadings of N-enriched

groundwater. Plant production, nitrogen uptake, and N

retention were significantly higher in the forested

buffer sites compared to the herbaceous buffer sites.

However, in herbaceous buffers, periodic harvesting

of herbaceous biomass contributed considerably to

the N retention. No relationship between lateral N

loading and plant productivity or N uptake was observed;

this indicated that plant growth was not N-limited.

In the winter period, decaying leaf litter had a

small but significant role in N retention in a majority of

the riparian ecosystems studied. Moreover, no responses

to the climatic gradient were found. Generally,

we can state that annual N retention in the vegetation

and litter compartment is substantial, making up

13-99% of the total N mitigation.

Ecological Engineering, 2005, V24, N5, MAY 30,

pp 465-482

05.3-136

Pan-European delta C-13 values of air and organic

matter from forest ecosystems

Hemming D, Yakir D, Ambus P, Aurela M, Besson C,

Black K, Buchmann N, Burlett R, Cescatti A,

Clement R, Gross P, Granier A, Grünwald T H,

Havrankova K, Janous D, Janssens I A, Knohl A,

Ostner B K, Kowalski A, Laurila T, Mata C, Marcolla B,

Matteucci G, Moncrieff J, Moors E J, Osborne B,

Pereira J S, Pihlatie M, Pilegaard K, Ponti F,

Rosova Z, Rossi F, Scartazza A, Vesala T

Israel, Denmark, Finland, Portugal, Ireland, Germany,

Switzerland, France, Italy, Scotland, Czech Republic,

Belgium, Netherlands

Ecology , Forestry , Meteorology & Atmospheric

Sciences , Plant Sciences

We present carbon stable isotope, delta(13)C, results

from air and organic matter samples collected during

98 individual field campaigns across a network of Carboeuroflux

forest sites in 2001 (14 sites) and 2002 (16

sites). Using these data, we tested the hypothesis that

delta(13)C values derived from large-scale atmospheric

measurements and models, which are rou-


tinely used to partition carbon fluxes between land

and ocean, and potentially between respiration and

photosynthesis on land, are consistent with directly

measured ecosystem-scale delta(13)C values. In this

framework, we also tested the potential of delta(13)C

in canopy air and plant organic matter to record regional-scale

ecophysiological patterns. Our network

estimates for the mean delta(13)C of ecosystem

respired CO2 and the related 'discrimination' of

ecosystem respiration, delta (er) and Delta(er), respectively,

were -25.6 +/- 1.9 parts per thousand and

17.8 +/- 2.0 parts per thousand in 2001 and -26.6 +/-

1.5 parts per thousand and 19.0 +/- 1.6 parts per

thousand in 2002. The results were in close agreement

with delta(13)C values derived from regionalscale

atmospheric measurement programs for 2001,

but less so in 2002, which had an unusual precipitation

pattern. This suggests that regional-scale atmospheric

sampling programs generally capture ecosystem

delta(13)C signals over Europe, but may be limited

in capturing some of the interannual variations. In

2001, but less so in 2002, there were discernable longitudinal

and seasonal trends in delta(er). From west

to east, across the network, there was a general enrichment

in C-13 (similar to 3 parts per thousand and

similar to 1 parts per thousand for the 2 years, respectively)

consistent with increasing Gorczynski continentality

index for warmer and drier conditions. In

2001 only, seasonal C-13 enrichment between July

and September, followed by depletion in November

(from about -26.0 parts per thousand to -24.5 parts

per thousand to -30.0 parts per thousand), was also

observed. In 2001, July and August delta(er) values

across the network were significantly related to average

daytime vapor pressure deficit (VPD) , relative

humidity (RH), and, to a lesser degree, air temperature

(T-a), but not significantly with monthly average

precipitation (P-m) . In contrast, in 2002 (a much wetter

peak season), delta(er) was significantly related

with T-a, but not significantly with VPD and RH. The

important role of plant physiological processes on

delta(er) in 2001 was emphasized by a relatively rapid

turnover (between 1 and 6 days) of assimilated carbon

inferred from time-lag analyses of delta(er) vs.

meteorological parameters. However, this was not evident

in 2002. These analyses also noted corresponding

diurnal cycles of delta(er) and meteorological parameters

in 2001, indicating a rapid transmission of

daytime meteorology, via physiological responses, to

the delta(er) signal during this season. Organic matter

delta(13)C results showed progressive C-13 enrichment

from leaves, through stems and roots to soil organic

matter, which may be explained by C-13 fractionation

during respiration. This enrichment was

species dependent and was prominent in angiosperms

but not in gymnosperms. delta(13)C values

of organic matter of any of the plant components did

not well represent short-term delta(er) values during

the seasonal cycle, and could not be used to partition

ecosystem respiration into autotrophic and heterotrophic

components.

Global Change Biology, 2005, V11, N7, JUL,

pp 1065-1093

1.7 COUPLED SYSTEMS AND CYCLES

05.3-137

Inorganic nitrogen storage in alpine snow pack in

the Central Alps (Switzerland)

Hiltbrunner E, Schwikowski M, Körner C

Switzerland

Cryology / Glaciology , Meteorology & Atmospheric

Sciences , Hydrology

In the alpine regions, more than half of the year's precipitation

is conserved as snow. We investigated inorganic

ion storage in snow pack at 2500 m (a.s.l.) in

the Central Alps, Switzerland. Chemical composition

of snow was dominated by nitrogenous and sulphate

ions. Ion pools showed high local and inter-annual

variability (2002, 2003) , but differences in ion pools

were not simply due to varying snow depth. The highest

soluble nitrogen (N) pools were found in March

(1.1-1.7 kg N ha(-1)). Later, in spring (April and May),

N pools in snow were significantly lower (0.5-0.8 kg N

ha(-1)). Ion storage in snow was compared with N

fluxes in rain, which ranged between 2. 0 kg and 3.3

kg N ha(-1) summer(-1). Both forms of wet precipitation

yielded a total wet N input into alpine grasslands

of maximal 5.0 kg N ha(-1) a(-1). Atmospheric N deposition

data for alpine ecosystems in the European

Alps are rare and the monitored data here deviate by

a factor of 2 from modelled N deposition. Nitrogen deposition

in the alpine zone of the Central Alps is much

smaller than previously assumed, but N pools stored

in snow correspond to, at the most, 34% of N released

by N mineralisation in alpine soils. Net N mineralisation

accounts for only a fraction of the annual N

uptake of alpine plant; thus, the additional N source

by melting snow contributes substantially to alpine

plants N uptake, particularly during periods when N

demands are highest.

Atmospheric Environment, 2005, V39, N12, APR,

pp 2249-2259

05.3-138

Water regime of metal-contaminated soil under

juvenile forest vegetation

Menon M, Hermle S, Abbaspour K C, Günthardt

Georg M S, Oswald S E, Schulin R

Switzerland

Ecology , Hydrology , Plant Sciences , Forestry , Agriculture,

Soil Sciences , Geochemistry & Geophysics

In a three-year factorial lysimeter study in Open Top

Chambers (OTCs) , we investigated the effect of topsoil

pollution by the heavy metals Zn, Cu, and Cd on

the water regime of newly established forest ecosystems.

Furthermore, we studied the influence of two

types of uncontaminated subsoils (acidic vs. calcareous)

and two types of irrigation water acidity (ambient

rainfall chemistry vs. acidified chemistry) on the response

of the vegetation. Each of the eight treatment

combinations was replicated four times. The contamination

(2700 mg kg(-1) Zn, 385 mg kg-1 Cu and 10

Global Change Abstracts – The Swiss Contribution 67


mg kg-1 Cd) was applied by mixing filter dust from a

non-ferrous metal smelter into the upper 15 cm of the

soil profile, consisting of silty loam (pH 6.5). The same

vegetation was established in all 32 lysimeters. The

model forest ecosystem consisted of seedlings of

Norway spruce (Picea abies), willow (Salix viminalis),

poplar (Populus tremula) and birch (Betula pendula)

trees and a variety of herbaceous understorey plants.

Systematic and significant effects showed up in the

second and third growing season after canopies had

closed. Evapotranspiration was reduced in metal contaminated

treatments, independent of the subsoil type

and acidity of the irrigation water. This effect corresponded

to an even stronger reduction in root growth

in the metal treatments. In the first two growing seasons,

evapotranspiration was higher on the calcareous

than on the acidic subsoil. In the third year the difference

disappeared. Acidification of the irrigation water

had no significant effect on water consumption, although

a tendency to enhance evapotranspiration became

increasingly manifest in the second and third

year. Soil water potentials indicated that the increasing

water consumption over the years was fed primarily

by intensified extraction of water from the topsoil in

the lysimeters with acidic subsoil, whereas also lower

depths became strongly exploited in the lysimeters

with calcareous subsoil. These patterns agreed well

with the vertical profiles of fine root density related

with the two types of subsoil. Leaf transpiration measurements

and biomass samples showed that different

plant species in part responded quite differently

and occasionally even in opposite ways to the metal

treatments and subsoil conditions. They suggest that

the year-to-year changes in treatment effects on water

consumption and extraction patterns were related

to differences in growth dynamics, as well as to shifts

in competitiveness of the various species. Results

showed that the uncontaminated subsoil offered a

possibility to compensate the reduction in root water

extraction in the topsoil under drought, as well as metal

stress.

Plant and Soil, 2005, V271, N1-2, APR, pp 227-241

05.3-139

Modeling diurnal to seasonal water and heat

exchanges at European Fluxnet sites

Stöckli R, Vidale P L

Switzerland

Modelling , Hydrology , Meteorology & Atmospheric

Sciences , Remote Sensing , Geochemistry &

Geophysics , Plant Sciences

The importance of linking measurements, modeling

and remote sensing of land surface processes has

been increasingly recognized in the past years since

on the diurnal to seasonal time scale land surface- atmosphere

feedbacks can play a substantial role in determining

the state of the near-surface climate. The

worldwide Fluxnet project provides long term measurements

of land surface variables useful for pro-

68

Global Change Abstracts – The Swiss Contribution

1.7 COUPLED SYSTEMS AND CYCLES

cess-based modeling studies over a wide range of climatic

environments. In this study data from six European

Fluxnet sites distributed over three latitudinal

zones are used to force three generations of LSMs

(land surface models): the BUCKET, BATS 1E and

SiB 2.5. Processes simulating the exchange of heat

and water used in these models range from simple

bare soil parameterizations to complex formulations of

plant biochemistry and soil physics. Results show that

- dependent on the climatic environment - soil storage

and plant biophysical processes can determine the

yearly course of the land surface heat and water budgets,

which need to be included in the modeling system.

The Mediterranean sites require a long term soil

water storage capability and a biophysical control of

evapotranspiration. In northern Europe the seasonal

soil temperature evolution can influence the winter energy

partitioning and requires a long term soil heat

storage scheme. Plant biochemistry and vegetation

phenology can drive evapotranspiration where no atmospheric-related

limiting environmental conditions

are active.

Theoretical and Applied Climatology, 2005, V80,

N2-4, APR, pp 229-243

05.3-140

Atmospheric deposition on swiss long-term forest

ecosystem research (LWF) plots

Thimonier A, Schmitt M, Waldner P, Rihm B

Switzerland

Meteorology & Atmospheric Sciences ,

Geochemistry & Geophysics , Modelling , Forestry

Atmospheric deposition of the major elements was estimated

from throughfall and bulk deposition measurements

on 13 plots of the Swiss Long-Term Forest

Ecosystem Research (LWF) between 1995 and 2001.

Independent estimates of the wet and dry deposition

of nitrogen (N) and sulfur (S) on these same plots

were gained from combined simplified models. The

highest deposition fluxes were measured at Novaggio

(Southern Switzerland), exposed to heavy air pollution

originating from the Po Plain, with throughfall fluxes

averaging 29 kg ha(-1) a(-1) for N and 15 kg ha(-1) a(-1)

for S. Low deposition fluxes were measured on the

plots above 1800 m, with throughfall fluxes lower than

4.5 kg ha(-1) a(-1) for N and lower than 3 kg ha (-1) a(-1)

for S. The wet deposition of N and S derived from bulk

deposition was close to the modeled wet deposition,

but the dry deposition derived from throughfall was

significantly lower than the modeled dry deposition for

both compounds. However, both the throughfall

method and the model yielded total deposition estimates

of N which exceeded the critical loads calculated

on the basis of long-term mass balance considerations.

These estimates were within or above the range

of empirical critical loads except above 1800 m.

Environmental Monitoring and Assessment, 2005,

V104, N1-3, MAY, pp 81-118


1.7 COUPLED SYSTEMS AND CYCLES / 2 PAST GLOBAL CHANGES

05.3-141

Prognostic canopy air space solutions for land

surface exchanges

Vidale P L, Stöckli R

Switzerland

Modelling , Geochemistry & Geophysics , Meteorology

& Atmospheric Sciences

Three generations of land surface models have been

developed over the Course of the last twenty years,

which include increasing levels of complexity. The latest

generation incorporates photosynthesis and physiological

C responses to environmental CO2, a gas

that is strongly controlled by atmospheric vertical stability

and by land surface exchanges. A new set of

prognostic equations, providing a new solution core

05.3-142

Late Maastrichtian and K/T paleoenvironment of

the eastern Tethys (Israel): mineralogy, trace and

platinum group elements, biostratigraphy and

faunal turnovers

Adatte T, Keller G, Stuben D, Harting M, Kramar U,

Stinnesbeck W, Abramovich S, Benjamini C M

Switzerland, USA, Germany, Israel

Zoology , Geology , Limnology , Geochemistry &

Geophysics , Paleontology

The late Maastrichtian to early Danian at Mishor

Rotem, Israel, was examined based on geochemistry,

bulk rock and clay mineralogies, biostratigraphy and

lithology. This section contains four red clay layers of

suspect impact or volcanic origin interbedded in chalk

and marly chalks. PGE anomalies indicate that only

the K/T boundary red layer has an Ir dominated PGE

anomaly indicative of an impact source. The late

Maastrichtian red clays have Pd dominated PGE

anomalies which coincide with increased trace elements

of terrigenous and volcanogenic origins. Deccan

or Syrian-Turkey arc volcanism is the likely

source of volcanism in these clay layers. Glauconite,

goethite and translucent amber spherules are present

in the clay layers, but the Si-rich spherules reported

by Rosenfeld et al. (1989) could not be confirmed.

The absence of Cheto smectite indicates that no altered

impact glass has been present. The red layers

represent condensed sedimentation on topographic

2 Past Global Changes

for one such land surface model, SiB2, is introduced

here. The new equation set makes use of canopy air

space variables which are prognostic and allow for

the storage of heat. water and carbon at that level,

providing both a new memory for the coupled system

and a better representation of observed canopy processes.

Results from off-line simulation using

FLUXNET data from Europe, over a range of environmental

and climatic conditions, indicate that the new

solution core is able to represent land surface exchanges

with equal or better skill than the set it replaces.

At the same time, this new formulation provides

a simplified mathematical framework, more suitable

for further model development.

Theoretical and Applied Climatology, 2005, V80, N2-

4, APR, pp 245-257

highs during sea level highstands. In the Negev area,

during the late Maastrichtian, the climate ranged from

seasonally wet to more arid conditions during zones

CF3 and CF2, with more humid wet conditions in the

latest Maastrichtian zone CF1 and in the early Danian,

probably linked to greenhouse conditions. Planktic

foraminifera experienced relatively high stress conditions

during this time as indicated by the low species

richness and low abundance of globotruncanids.

Times of intensified stress are indicated by the disaster

opportunist Guembelitria blooms, which can be

correlated to central Egypt and also to Indian Ocean

localities associated with mantle plume volcanism.

Marine plankton thus support the mineralogical and

geochemical observations of volcanic influx and reveal

the detrimental biotic effects of intense volcanism.

Bulletin de la Societe Geologique de France, 2005,

V176, N1, pp 37-55

05.3-143

Palaeoclimatology - Formation of Precambrian

sediment ripples - Reply

Allen P, Hoffman P

Switzerland, USA

Geology , Paleontology

Nature, 2005, V436, N7049, JUL 21, pp E1-E2

Global Change Abstracts – The Swiss Contribution 69


05.3-144

Differential dissolution of Lake Baikal diatoms:

correction factors and implications for

palaeoclimatic reconstruction

Battarbee R W, Mackay A W, Jewson D H,

Ryves D B, Sturm M

England, Switzerland

Geochemistry & Geophysics , Marine & Freshwater

Biology , Limnology , Paleontology

In order to assess how faithfully the composition of diatom

assemblages in the recent sediments of Lake

Baikal represents the composition of the planktonic diatom

populations in the lake, we have compared the

flux of diatoms from the water column (i.e., "expected'

in the sediment) with the accumulation rates of the

same diatom taxa (i.e., "observed' in the sediment)

from BAIK 38, a sediment core collected in the south

basin of the lake. Whilst there are many uncertainties,

the results indicate that only approximately 1% of the

phytoplankton crop is preserved in the sediment and

some species are more affected by dissolution than

others. These findings are comparable to similar studies

undertaken in the marine environment. In terms of

differential dissolution, our studies suggest that the

endemic taxa (e.g., Cyclotella minuta and Aulacoseira

baicalensis) are the most resilient, whereas cosmopolitan

taxa such as Nitzschia acicularis and Synedra

acus are the least resilient. N. acicularis dissolves

in the water column, but for other taxa, most dissolution

takes place at the surface sediment-water interface.

We use the data to develop a series of speciesspecific

correction factors that allow the composition

of the source populations to be reconstituted, and we

argue that failure to take these processes into account

can undermine the use of the diatom and biogenic

silica record in Lake Baikal for palaeo-productivity

and palaeoclimate reconstruction.

Global and Planetary Change, 2005, V46, N1-4, APR,

pp 75-86

05.3-145

Release of gas bubbles from lake sediment traced

by noble gas isotopes in the sediment pore water

Brennwald M S, Kipfer R, Imboden D M

Switzerland

Paleontology , Limnology , Geochemistry &

Geophysics , Hydrology , Meteorology & Atmospheric

Sciences , Marine & Freshwater Biology ,

Oceanography

The release of gas bubbles from lacustrine or oceanic

sediments into the overlying water (ebullition) is a major

mechanism for the discharge of biogenic or geogenic

gases into the water body. Ebullition of

methane or carbon dioxide, for instance, contributes

considerably to the release of these potent greenhouse

gases through the sediment/water interface.

Depending on the rate of ebullition, the pore water will

70

Global Change Abstracts – The Swiss Contribution

2 PAST GLOBAL CHANGES

show a depletion in dissolved atmospheric noble gases,

because the poorly soluble noble gases escape

from the pore water into the gas bubbles. In this

study, the depletion of dissolved noble gases in sediment

pore water was analyzed for the first time to

study bubble formation and ebullition in sediments.

The noble gases in the pore water of the sediments of

Soppensee (Switzerland) show a distinct depletion

due to ebullition of biologically produced methane.

This depletion is lowest in the deep sediment and increases

towards the sediment surface. The noble gas

isotope ratios in the pore water indicate that vertical

diffusion barely affects the observed noble gas profiles.

The isotope ratios further show that the methane

bubbles remain long enough in the sediment to attain

noble gas solubility equilibrium before escaping into

the overlying water. The volume of gas released from

the sediment by ebullition can therefore be reconstructed

from the extent of the noble gas depletion in

the pore water using a simple gas-equilibration model.

The noble gas profiles in the sediment indicate that

ebullition increased in Soppensee during the

Holocene, and that ebullition contributed strongly to

the release of methane from the sediment. Our case

study thus illustrates that noble bases are sensitive

proxies for the release of gas from lacustrine and marine

sediments or similar aquatic environments.

Earth and Planetary Science Letters, 2005, V235,

N1-2, JUN 30, pp 31-44

05.3-146

8,000 years of human warmth

Broecker W S, Stocker T F

USA, Switzerland

Meteorology & Atmospheric Sciences , Social

Sciences , Paleontology

Scientific American, 2005, V293, N1, JUL p 9

05.3-147

Combined winter climate regimes over the North

Atlantic/European sector 1766-2000

Casty C, Handorf D, Sempf M

Germany

Meteorology & Atmospheric Sciences , Paleontology

This paper presents combined winter climate regimes

for the 1766-2000 period over the North Atlantic/European

sector. We expand previous studies on recurrent

regimes by combining spatially high-resolved independent

reconstructions of the 500 hPa geopotential

height, land surface air temperature, and precipitation

fields. Nonlinear Principal Component Analysis is applied

to the data in order to account for the underlying

nonlinear dynamics of climate regimes. Three recurrent

winter climate regimes are detected. One regime

resembles in its pressure, temperature, and precipitation

pattern the positive phase of the North Atlantic


Oscillation, whereas the other two regimes are European

blocking situations.

Geophysical Research Letters, 2005, V32, N13,

JUL 1, ARTN: L13801

05.3-148

Paleoclimatic control of biogeographic and

sedimentary events in Tethyan and peri-Tethyan

areas during the Oxfordian (Late Jurassic)

Cecca F, Garin B M, Marchand D, Lathuiliere B,

Bartolini A

France, Switzerland

Meteorology & Atmospheric Sciences , Limnology ,

Geochemistry & Geophysics , Paleontology ,

Geomorphology , Geology

The paleobiogeographical distribution of Oxfordian

ammonites and coral reefs in northern and Central

Europe, the Mediterranean area, North and East

Africa, and the Middle East and Central Asia is compared

with the distribution in time and space of the

most important lithofacies. Interest in the Oxfordian is

focused on changes in facies and in biogeographical

patterns that can be interpreted as the results of climatic

events. Paleotemperature trends inferred from

oxygen isotopes and paleoclimatic simulations are

tested against fossil and facies data. A Late Callovian

Early Oxfordian crisis in carbonate production is indicated

by the widespread absence of Lower Oxfordian

reefal formations. There is a gap (hiatus) in deposition

on epicontinental platforms, with Middle Oxfordian deposits

resting paraconformably on Upper Callovian,

while shales accumulated in adjacent intracratonic

basins. Simultaneously, in Mediterranean Tethys, radiolarites

accumulated in deep troughs while Rosso

Ammonitico facies formed on pelagic swells. However,

deposition oil swells wits also discontinuous with

numerous gaps (hiatuses) and sequences that are

much reduced in thickness. Middle Callovian deposits

are generally overlain by Middle Oxfordian limestones,

The dearth of carbonates is consistent with it

cooling event lasting about I My. By the middle Oxfordian

a warming, leading to "greenhouse' type conditions,

is suggested on the basis of both biogeographical

(mostly coral-reef distribution) and geochemical

data. Carbonates spread onto an extensive European

platform while radiolarites reached a maximum development

in the Mediterranean Tethys. Two distinct latitudinal

belts, with seemingly different accumulation

regimes, are therefore inferred. Similar latitudinal

belts were also present in the late Oxfordian, when

carbonates were widespread. The distribution of

reefal facies in the late Oxfordian- early Kimmeridgian

fits relatively well with GCMs simulations that imply

low rainfall in the Tethyan Mediterranean area and

slightly higher precipitation in central and northern Europe.

Local salinity variations, reflecting more and or

2 PAST GLOBAL CHANGES

humid conditions, may bias the paleotemperature signal

inferred from delta(18)O values. Biogeographical

and facies distributions, combined with delta(18)O

values, unravel the ambiguity and support a Late

Callovian-Early Oxfordian cooling followed by warming

in the later Oxfordian.

Palaeogeography Palaeoclimatology Palaeoecology,

2005, V222, N1-2, JUN 21, pp 10-32

05.3-149

Modem pollen-vegetation relationships in the

Champsaur valley (French Alps) and their

potential in the interpretation of fossil pollen

records of past cultural landscapes

Court Picon M, Buttler A, de Beaulieu J L

France, Switzerland

Plant Sciences , Paleontology

This study is an attempt to evaluate the relationships

between the vegetation and the modem pollen rain as

a contribution to palaeoecological research. Pollen

analysis of surface moss polsters and floristic records

has been undertaken for 51 sampling points distributed

all over the study area (Champsaur valley, Hautes-

Alpes, France), within different vegetation and landuse

types and along a west-east altitudinal transect,

ranging from 870 to 2200 in a.s.l. The pollen and vegetation

data were analysed independently using numerical

methods (clustering and correspondence

analysis) to investigate how vegetation is reflected in

pollen assemblages. There was a good agreement

between classifications and ordinations of the two

data-sets and a pollen-analytical separation of different

types of human activities was found despite the

major gradients related to altitude and soil moisture.

Both the AP/NAP ratio and the major pollen type percentage

ranges given for each vegetation type were

however very wide because of the typical fine-scale

mosaic of the landscape in this region. Detailed comparisons

of the two data- sets showed consistent differences

between vegetation and pollen assemblages.

Misclassifications of some modem pollen

spectra were mainly attributed to differential pollen

representation between species, but also to the effect

of various land-use practices on flowering and pollination

of herbaceous plant taxa. Moreover these differences,

as well as discrepancies with earlier published

data from lowlands of southern France and other

parts of western Europe, are promoted by complex

pollen dispersal which characterizes mountain environments.

Although an overlap of characteristics thus

exists between pollen assemblages, we were able to

recognize specific features and indicator pollen taxa

have been identified for each natural, semi-natural

and human-induced vegetation type.

Review of Palaeobotany and Palynology, 2005, V135,

N1-2, JUN, pp 13-39

Global Change Abstracts – The Swiss Contribution 71


05.3-150

Flux of lipophilic photosynthetic pigments to the

surface sediments of Lake Baikal

Fietz S, Sturm M, Nicklisch A

Germany, Switzerland

Paleontology , Limnology , Marine & Freshwater

Biology , Geochemistry & Geophysics

The pigment flux to the sediment surface was studied

in Lake Baikal to evaluate the validity of approaches

reconstructing long-term variations in standing crops

of phytoplankton by fossil pigment analysis. Chlorophylls

and carotenoids were analysed by HPLC in

suspended and settling matter and in the surface sediment

of the central south basin (c. 1400-m water

depth). Sedimentation rates of dry matter, organic carbon

and nitrogen were also determined. The flux of

particulate matter in 40 in, directly below the euphotic

zone, amounted to 14.9 g m(-2) month(-1) with a carbon

content of 21.9%, and an atomic C/N ratio of

14.8. The pigment flux was 12.1 µmol m(-2) month(-1)

chlorophyll a, 40.8 µmol m(-2) month(-1) pheophorbide

a, 6.5 µmol m(-2) month(-1) pheophytin a, 2.1

µmol m (-2) month(-1) chlorophyllide a, and 0.3 µmol

m(-2) month(-1) pyropheophytin a. The decay during

sedimentation can be described by two-exponential or

decay regression models for organic carbon, total nitrogen,

chlorophyll a, pheophorbide a, chlorophyllide

a, chlorophyll b, and most carotenoids, but not for

pheophytin a, pheophytin b, and pyropheophytin a.

The two-phase character of the models outlined that,

for the former components, the flux diminished strongly

in a first phase down to 250-m water depth and remained

rather stable below 250 m. The chlorophyll

a/carbon ratio also decreased with depth, whereas

the pheophytin a/carbon ratio and the pyropheophytin

a /carbon ratio increased with depth. From chlorophyll

a, plus its degradation products, 28% reached the

lake bottom when compared to the sedimentation below

the euphotic zone. Based on the marker pigments

fucoxanthin, chlorophyll b, and zeaxanthin, the contribution

of the main phytoplankton groups to the settled

chlorophyll a was estimated as 87% Bacillariophyceae+Chrysophyceac,

11% Chlorophyta, and 2%

cyanobacterial picoplankton. These relationships

changed only little during the sedimentation through

the whole water column, but diverged from compositions

calculated for the summer standing crop.

Global and Planetary Change, 2005, V46, N1-4, APR,

pp 29-44

05.3-151

A glacial stage spanning the Antarctic Cold

Reversal in Torres del Paine (51 degrees S), Chile,

based on preliminary cosmogenic exposure ages

Fogwill C J, Kubik P W

Scotland, Switzerland

Cryology / Glaciology , Geochemistry & Geophysics ,

Geomorphology , Paleontology

72

Global Change Abstracts – The Swiss Contribution

2 PAST GLOBAL CHANGES

Initial cosmogenic Be-10 results from a former ice limit

in Torres del Paine indicate a short-lived stillstand or

readvance of Patagonian ice culminating at 12-15 kyr

BP with a mean age of 13.2 + /- 0.8 kyr Bp. The

glacier extended some 40 km beyond the present ice

margin and was within 15 km of the presumed Last

Glacial Maximum limits. The timing of the glacier

stage spans the cooling event recorded in Antarctic

ice cores, termed the Antarctic Cold Reversal (14.5-

12.9 kyr Bp). This result implies that glaciers at these

latitudes were out of phase with those in the northern

hemisphere; instead they mirrored the climate structure

of Antarctica during the last glacial to interglacial

transition.

Geografiska Annaler Series A Physical Geography,

2005, V87A, N2, pp 403-408

05.3-152

Phosphogenesis and organic-carbon preservation

in the miocene monterey formation at Naples

beach, California - The monterey hypothesis

revisited

Föllmi K B, Badertscher C, de Kaenel E, Stille P,

John C M, Adatte T, Steinmann P

Switzerland, France

Paleontology , Geology , Geomorphology

The middle part of the Miocene Monterey Formation

at Naples Beach, west of Santa Barbara, California, is

predominantly composed of organic-rich mudstone interstratified

with phosphatic laminae. Minor lithologies

include volcanic ash, dolomite, porcelanite and chert,

and condensed phosphatic beds. Sediments dated as

14.3-13.5 Ma have average total organic carbon

(TOC) values around 8.5 wt%, and organic carbon

(OC) accumulation rates are around 565 mg/cm(2)/k.y.

Sediments dated as 13.5-13 Ma are characterized by

average TOC values of 12.6 wt% and OC accumulation

rates of around 1130 Mg/cm(2)/k.y. The interval

between 13 and 10.6 Ma is marked by condensation;

average TOC values are around 8.6 wt%, and OC accumulation

rates diminished to around 55 mg/cm(2)/k.y.

The last interval studied is dated as 10.6-9.4 Ma, and

average TOC values are around 6 wt%, whereas OC

accumulation rates rose again to 320 Mg/cm(2)/k.y.

The presence of erosional surfaces, angular unconformities,

and reworked clasts and nodules suggests

that bottom-current activity and gravity-flow deposition

have been instrumental in sediment accumulation.

The phosphatic laminae were precipitated at a very

early stage of diagenesis during periods of nonsedimentation.

They formed less permeable sedimentary

lids and may as such have contributed to enhanced

OC preservation. Between 13 and 10.6 Ma, the thusformed

phosphatic laminae were frequently subjected

to subsequent sediment winnowing and reworking, resulting

in the formation of condensed phosphatic

beds. Calculated P:C molar ratios suggest that (1) the

measured section is highly enriched in phosphorus

(P) relative to OC; (2) regeneration of organic P from


organic-matter decomposition was negligible; and (3)

the source of P was external, likely upwelled bottom

water rich in inorganic P. In spite of good preservation

conditions and correspondingly high TOC contents,

the overall OC accumulation rates are moderate in

comparison to those of actual high productivity areas,

which is mainly due to the episodic character of depositional

processes and the intervening long periods of

non- deposition and sediment reworking. They preclude

this section, and by extrapolation, the Monterey

Formation in general from being an important OC sink

during the middle Miocene. Alternatively, large OC

sinks were probably created on the continent (lignite

deposits) and in sedimentary depocenters, which received

increasing amounts of detrital sediments due

to a combination of climate change, spreading of

grasslands, and the increasing importance of mountain

chains such as the Himalaya. The associated

high nutrient fluxes may have been involved in the

backstepping and drowning of carbonate platforms

and in the generation of widespread phosphate-rich

deposits during the late early and early middle

Miocene.

Geological Society of America Bulletin, 2005, V117,

N5-6, MAY-JUN, pp 589-619

05.3-153

Relative age dating of Alpine rockglacier surfaces

Frauenfelder R, Laustela M, Kaab A

Switzerland

Cryology / Glaciology , Paleontology

The present work discusses the application of photogrammetry,

and the measurements of Schmidt-hammer

rebound values and weathering rind thicknesses,

for the relative age dating of Alpine rockglaciers,

based on data from six rockglaciers in the Swiss Alps.

Rockglaciers are formed by the continuous deformation

of ice-rich debris material, with the result that the

age of the surface becomes greater along the flowlines

from the root zone to the rockglacier front. This

can be demonstrated by applying both the Schmidthammer

rebound values (which diminish as weathering,

or duration of surface exposure, increases) and

the weathering rind thicknesses (which grow as

weathering increases). The results of these two methods

correlate well with chronologies estimated from

photogrammetric streamline interpolations. They also

indicate that the minimum surface age of the investigated

rockglaciers is between 3 and 5 ka. This implies

that most of these rockglaciers began to evolve during

the early Holocene or, at the latest, after the end of

the Holocene temperature optimum (approx. 5,000 y

BP).

Zeitschrift für Geomorphologie, 2005, V49, N2, JUN,

pp 145-166

2 PAST GLOBAL CHANGES

05.3-154

Early-Holocene afforestation processes in the

lower subalpine belt of the Central Swiss Alps as

inferred from macrofossil and pollen records

Gobet E, Tinner W, Bigler C, Hochuli P A, Ammann B

Switzerland, Sweden

Plant Sciences , Geochemistry & Geophysics ,

Paleontology

To reconstruct the vegetation history of the Upper Engadine,

continuous sediment cores covering the past

11800 years from Lej da Champfer and Lej da San

Murezzan (Upper Engadine Valley, c. 1800 m a.s.l.,

southeastern Switzerland) have been analysed for

pollen and plant macrofossils. The chronologies of the

cores are based on 16 and 22 radiocarbon dates, respectively.

The palaeobotanical records of both lakes

are In agreement for the Holocene, but remarkable

differences exist between the sites during the period

11100 to 10 500 cal. BP, when Lej da Champfer was

affected by re-sedimentation processes. Macrofossil

data suggest that Holocene afforestation began at

around 11400 cal. BP. A climatic deterioration, the

Preboreal Oscillation, stopped and subsequently delayed

the establishment of trees until c. 11000 cal. BP,

when first Betula, then Pinus sylvestris/mugo, then

Larix 300 years later, and finally Pinus cembra expanded

within the lake catchment. Treeline was at c.

1500 m during the Younger Dryas (12542-11550 cal.

BP) in the Central Alps. Our results, along with other

macrofossil studies from the Alps, suggest a nearly simultaneous

afforestation (e.g., by Pinus sylvestris in

the lower subalpine belt) between 1500 and 2340 m

a.s.l. at around 11400 to 11300 cal. BP. We suggest

that forest-limit species (e.g., Pinus cembra, Larix decidua)

could expand faster at today's treeline (c. 2350

m a.s.l.), than 550 m lower. Earlier expansions at

higher altitudes probably resulted from reduced competition

with low- altitude trees (e.g. Pinus sylvestris)

and herbaceous species. Comparison with other proxies

such as oxygen isotopes, residual Delta (14)C,

glacier fluctuations, and alpine climatic cooling phases

suggests climatic sensitivity of vegetation during

the early Holocene.

Holocene, 2005, V15, N5, JUL, pp 672-686

05.3-155

Calcium isotope (delta Ca-44/40) variations of

Neogene planktonic foraminifera

Heuser A, Eisenhauer A, Bohm F, Wallmann K,

Gussone N, Pearson P N, Nagler T F, Dullo W C

Germany, Wales, Switzerland

Oceanography , Paleontology , Geochemistry &

Geophysics , Modelling

(1) Measurements of the calcium isotopic composition

(delta(44/40)Ca) of planktonic foraminifera from the

western equatorial Pacific and the Indian sector of the

Global Change Abstracts – The Swiss Contribution 73


Southern Ocean show variations of about 0.6% over

the past 24 Myr. The stacked delta(44/40) Ca record

of Globigerinoides trilobus and Globigerina bulloides

indicates a minimum in delta(44/40) Ca-sw ( seawater

calcium) at 15 to 16 Ma and a subsequent general increase

toward the present, interrupted by a second

minimum at 3 to 5 Ma. Applying a coupled calcium/

carbon cycle model, we find two scenarios that can

explain a large portion of the observed delta(44/40)

Ca-sw variations. In both cases, variations in the Ca

input flux to the ocean without proportional changes in

the carbonate flux are invoked. The first scenario increases

the riverine calcium input to the ocean without

a proportional increase of the carbonate flux. The

second scenario generates an additional calcium flux

from the exchange of Ca by Mg during dolomitization.

In both cases the calcium flux variations lead to drastic

changes in the seawater Ca concentrations on million

year timescales. Our delta(44 /40) Ca-sw record

therefore indicates that the global calcium cycle may

be much more dynamic than previously assumed.

Paleoceanography, 2005, V20, N2, JUN 4,

ARTN: PA2013

05.3-156

Glacial/interglacial changes in subarctic North

Pacific stratification

Jaccard S L, Haug G H, Sigman D M, Pedersen T F,

Thierstein H R, Rohl U

Switzerland, Germany, USA, Canada

Cryology / Glaciology , Oceanography , Meteorology

& Atmospheric Sciences , Paleontology

Since the first evidence of low algal productivity during

ice ages in the Antarctic Zone of the Southern

Ocean was discovered, there has been debate as to

whether it was associated with increased polar ocean

stratification or with sea-ice cover, shortening the productive

season. The sediment concentration of biogenic

barium at Ocean Drilling Program site 882 indicates

low algal productivity during ice ages in the

Subarctic North Pacific as well. Site 882 is located

southeast of the summer sea-ice extent even during

glacial maxima, ruling out sea-ice-driven light limitation

and supporting stratification as the explanation,

with implications for the glacial cycles of atmospheric

carbon dioxide concentration.

Science, 2005, V308, N5724, MAY 13, pp 1003-1006

05.3-157

Modeling tree species migration in the Alps

during the Holocene: What creates complexity?

Lischke H

Switzerland

74

Global Change Abstracts – The Swiss Contribution

2 PAST GLOBAL CHANGES

Plant Sciences , Modelling , Ecology , Paleontology ,

Biodiversity

The tree migration model TreeMig is presented as an

example for modeling a complex ecological system.

The model was derived from a forest gap model, reducing

the gap models' complexity by model aggregation

and includes elements for showing complex behavior:

many state variables, non-linear process functions,

feedbacks and spatial interactions. Additionally,

the model depends on external variables, namely climate.

In a case study, the tree migration in the highly

structured environment of the region of Valais in the

Swiss Alps during the Holocene was simulated. The

simulations were run on a grid with I km x I km resolution

with a yearly time step. A scenario of temperature-anomalies

in the Holocene, spatially interpolated

climate data and times of species immigration into the

simulation area was used as input. The simulation results

were evaluated with regard to the spatio-temporal

species composition and complexity, i.e. species

diversity and spatio-temporal unevenness. Two indices

of complexity were calculated from the simulated

species biomasses in space and time: the Shannon-Weaver

index for species diversity and an index

of spatio-temporal complexity (unevenness) of total

biomass. Both indices depended on climate, but in different

ways. Tree species diversity was positively related

to degree day sum, i.e. was high at low and

smaller at high attitudes. Spatio-temporal complexity

in turn was high at the alpine timberline, but very low

at lower elevations. Increased complexity independent

from climate occurred during migration waves

into the simulation area. Spatio-temporal complexity

was high when the first species colonized the region.

Tree species diversity changed during the immigration

wave of each immigrating species, particularly that of

the dominant species Picea abies. At the fronts of the

immigration waves in particular, spots of increased diversity

appeared. However, no formation of stable

patchy patterns was observed at the studied scale.

The standard simulation, reflecting climate patterns

and endogenous processes such as local dispersal,

long-range migration and succession was compared

to simulations, where single or all endogenous processes

were excluded. The dissimilarities between

the species compositions of these simulations indicated

that after immigration of dominant species succession

and migration strongly influence the species pattern,

succession over centuries and migration over

millennia. I conclude that the species pattern and its

complexity, as shown by the model simulations, were

to a great extent determined by external factors and

their complexity. After changes in the boundary conditions,

succession and migration had a strong influence.

Ecological Complexity, 2005, V2, N2, JUN,

pp 159-174


05.3-158

1000 years of climate variability in central Asia:

assessing the evidence using Lake Baikal (Russia)

diatom assemblages and the application of a

diatom-inferred model of snow cover on the lake

Mackay A W, Ryves D B, Battarbee R W, Flower R J,

Jewson D H, Rioual P, Sturm M

England, Peoples R China, Switzerland

Limnology , Paleontology , Marine & Freshwater

Biology , Modelling

The mainly endemic phytoplankton record of Lake

Baikal has been used in this study to help interpret climate

variability during the last 1000 years in central

Asia. The diatom record was derived from a short

core taken from the south basin and has been shown

to be free from any sedimentary heterogeneities. We

employ here a diatom-based inference model of snow

accumulation on the frozen lake for the first time

(r(boot)(2)=0.709; RMSEP=0.120 log cm). However,

palaeoenvironmental reconstructions have been improved

by the use of correction factors, specifically

developed for the dominant phytoplankton (Aulacoseira

baicalensis, Aulacoseira skvortzowii, Cyclotella

minuta, Stephanodiscus meyerii and Synedra acus) in

the south basin of Lake Baikal. Cluster analysis identifies

three significant zones in the core, zone I (c. 880

AD-c. 1180 AD), zone 2 (c. 1180-1840 AD) and zone 3

(c. 1840-1994 AD), coincident with the Medieval

Warm Period (MWP), the Little Ice Age (LIA) and the

period of recent warming, respectively. Our results indicate

that S. acus dominated the diatom phytoplankton

within zone I coincident with the MWP. S. acus is

an opportunistic species that is able to increase its net

growth when A. baicalensis does not. During this period,

conditions are likely to have been unfavourable for

the net increases in A. baicalensis growth due to the

persistence of warm water in the lake, together with

an increased length of summer stratification and delay

in timing of the autumnal overturn. In zone 2, spring

diatom crops blooming under the ice declined in

abundances due in part to increased winter severity

and snow cover on the lake. Accumulating snow on

the lake is likely to have arisen from increased anticyclonic

activity, resulting in prolonged winters expressed

during the LIA. Thick, accumulating snow

cover inhibits light penetration through the ice, thereby

having negative effects on cell division rate and extent

of turbulence underneath the ice. Consequently,

only taxa whose net growth occurs during autumn

overturn (C. minuta) predominate in the lake at this

time. Diatom census data and reconstructions of

snow accumulation suggest that warming in the Lake

Baikal region started as early as c. 1750 AD, with a

shift from taxa that bloom during autumn overturn to

assemblages that begin to grow underneath the

frozen lake in spring. Very recent increases and subsequent

decline of S. acus in the surface sediments of

the lake mirror monitoring records of this species over

the last 50 years. Our study confirms that, over the

last 1000 years, physical processes are important in

2 PAST GLOBAL CHANGES

determining planktonic diatom populations in the lake

and highlights the value of integrated plankton, trap,

and sediment studies for improving quantitative

palaeoenvironmental reconstructions from fossil material.

Global and Planetary Change, 2005, V46, N1-4, APR,

pp 281-297

05.3-159

GRIP deuterium excess reveals rapid and orbitalscale

changes in Greenland moisture origin

Masson Delmotte V, Jouzel J, Landais A, Stievenard M,

Johnsen S J, White J W C, Werner M, Sveinbjornsdottir

A, Fuhrer K

France, Denmark, Iceland, USA, Germany,

Switzerland

Hydrology , Cryology / Glaciology , Meteorology &

Atmospheric Sciences , Paleontology

The Northern Hemisphere hydrological cycle is a key

factor coupling ice sheets, ocean circulation, and polar

amplification of climate change. Here we present a

Northern Hemisphere deuterium excess profile covering

one climatic cycle, constructed with the use of

delta(18)O and delta D Greenland Ice Core Project

(GRIP) records. Past changes in Greenland source

and site temperatures are quantified with precipitation

seasonality taken into account. The imprint of obliquity

is evidenced in the site-to-source temperature gradient

at orbital scale. At the millennial. time scale,

GRIP source temperature changes reflect southward

shifts of the geographical locations of moisture

sources during cold events, and these rapid shifts are

associated with large-scale changes in atmospheric

circulation.

Science, 2005, V309, N5731, JUL 1, pp 118-121

05.3-160

Chronology of the last glaciation in central Strait

of Magellan and Bahia Inutil, southernmost South

America

Mcculloch R D, Fogwill C J, Sugden D E, Bentley M J,

Kubik P W

Scotland, England, Switzerland

Cryology / Glaciology , Geochemistry & Geophysics ,

Geomorphology , Paleontology

Glacier fluctuations in the Strait of Magellan tell of the

climatic changes that affected southern latitudes at c.

53-55 degrees S during the Last Glacial Maximum

(LGM) and Late-glacial/Holocene transition. Here we

present a revised chronology based on cosmogenic

isotope analysis, C-14 assays, amino acid racemisation

and tephrochronology. We unpick the effect of

bedrock-derived lignite which has affected many C-14

dates in the past and synthesise new and revised

dates that constrain five glacier advances (A to E).

Global Change Abstracts – The Swiss Contribution 75


Advance A is prior to the LGM. LGM is represented by

Advance B that reached and largely formed the arcuate

peninsula Juan Mazia. Carbon-14 and Be-10 dating

show it occurred after 31 250 cal yrs BP and culminated

at 25 200-23 100 cal yrs BP and was then

followed by the slightly less extensive advance C

sometime before 22 400-20 300 cal yrs BP. This pattern

of an early maximum is found elsewhere in South

America and more widely. Stage D, considerably less

extensive, culminated sometime before 17 700-17

600 cal yrs BP and was followed by rapid and widespread

glacier retreat. Advance E, which dammed a

lake, spanned 15500-11770 cal yrs Bp. This latter advance

overlaps the Bolling-Allerod interstadials and

the glacier retreat occurs during the peak of the

Younger Dryas stadial in the northern hemisphere.

However, the stage E advance coincides with the

Antarctic Cold Reversal (c. 14 800-12 700 cal yrs Bp)

and may indicate that some millennial-scale climatic

fluctuations in the Late-glacial period are out of phase

between the northern and southern hemispheres.

Geografiska Annaler Series A Physical Geography,

2005, V87A, N2, pp 289-312

05.3-161

Internal carbon and nutrient cycling in Lake

Baikal: sedimentation, upwelling, and early

diagenesis

Müller B, Maerki M, Schmid M, Vologina E G,

Wehrli B, Wüest A, Sturm M

Switzerland

Limnology , Geochemistry & Geophysics ,

Paleontology

The internal cycles of carbon, silica, nitrogen, and

phosphorus in the South and North Basins of Lake

Baikal were quantified in the frame of a multidisciplinary

collaboration. Fluxes of particulate organic

matter from the epilimnion to the deep water were

quantified with integrating sediment traps deployed at

200- to 250-m water depth and compared with fluxes

measured in near-bottom traps to reveal mineralization

in the water column. Sedimentation rates were

determined with dated sediment cores to calculate

mass accumulation rates of elements in the sediment.

Advective and turbulent transport of dissolved nutrients

in the water column was based on a set of monitoring

data, which included temperature and current

data, as well as hydrochemical data of the water column.

Diffusive fluxes from the sediment to the overlying

water column were determined by applying different

porewater sampling techniques. The combination

of these data resulted in consistent internal budgets

for carbon, nitrogen, and phosphorus in Lake Baikal:

the new production in the South Basin was 1730

mmol C m(-2) year(-1) and the mass accumulation

rate in the sediment 220 mmol C m(-2) year(-1),

whereas in the more secluded North Basin, new production

was only 1220 mmol C m(-2) year(-1) and

mass accumulation rate 125 mmol C m(-2) year(-1).

76

Global Change Abstracts – The Swiss Contribution

2 PAST GLOBAL CHANGES

Fluxes of particle- bound nitrogen, phosphorus, and

biogenic silica were by about 30% smaller in the

North Basin than in the South Basin. Export fluxes of

nitrogen from the surface zone to the deep water

were 150 mmol N and 100 mmol N m(-2) year(-1).

Denitrification rates in the sediment were estimated

from mass-loss calculation to 38 and 53 mmol N m

(-2) year (-1) for the South and North Basin, respectively,

corresponding to 25% and 52% of the total nitrogen

input to the hypolimnion. Nitrogen (19 and 13

mmol m(-2) year(-1)) was finally buried in the sediments

of the South and North Basins; 10.1 and 3.5

mmol P m(-2) year(-1), and 1830 and 1400 mmol Si

m(-2) year(-1) were transferred to the deep water in

the South and North Basin where 28% and 70% P,

and 64% and 54% Si were retained in the sediments.

A diatom bloom occurred during our sampling period

of 2 years, which usually occurs only every 3 to 5

years. Accordingly, Si flux data from sediment traps

were increased by an estimated 50% compared with

the long-term average illustrating the necessity of several

years of field measurements to compensate for

the natural dynamics of Lake Baikal.

Global and Planetary Change, 2005, V46, N1-4, APR,

pp 101-124

05.3-162

Effects of sample mass and macrofossil type on

radiocarbon dating of arctic and boreal lake

sediments

Oswald W W, Anderson P M, Brown T A, Brubaker L

B, Hu F S, Lozhkin A V, Tinner W, Kaltenrieder P

USA, Russia, Switzerland

Limnology , Geochemistry & Geophysics ,

Paleontology , Plant Sciences

Dating lake sediments by accelerator mass spectrometry

(AMS) C-14 analysis of terrestrial plant macrofossils

overcomes one of the main problems associated

with dating bulk sediment samples, i.e., the presence

of old organic matter. Even so, many AMS dates from

arctic and boreal sites appear to misrepresent the age

of the sediment. To understand the nature of these

apparent dating anomalies better, we conducted a series

of C-14 dating experiments using samples from

Alaskan and Siberian lake-sediment cores. First, to

test whether our analytical procedures introduced a

sample-mass bias, we obtained C-14 dates for different-sized

pieces of single woody macrofossils. In

these sample-mass experiments, statistically equivalent

ages were found for samples as small as 0.05 mg

C. Secondly, to assess whether macrofossil type influenced

dating results, we conducted sample-type experiments

in which C-14 dates were obtained for different

macrofossil types sieved from the same depth

in the sediment. We dated materials from multiple levels

in sediment cores from Upper Capsule Lake

(North Slope, northern Alaska) and Grizzly Lake (Copper

River Basin, southern Alaska) and from single

depths in other records from northern Alaska. In sev-


eral of the experiments there were significant discrepancies

between dates for different plant tissues, and

in most cases wood and charcoal were older than other

macrofossil types, usually by several hundred

years. This pattern suggests that C-14 dates for

woody macrofossils may misrepresent the age of the

sediment by centuries, perhaps because of their

longer terrestrial residence time and the potential inbuilt

age of long-lived plants. This study identifies why

some C-14 dates appear to be inconsistent with the

overall age-depth trend of a lake-sediment record,

and it may guide the selection of C-14 samples in future

studies.

Holocene, 2005, V15, N5, JUL, pp 758-767

05.3-163

Late quaternary history of the coastal Wahiba

Sands, Sultanate of Oman

Preusser F, Radies D, Driehorst F, Matter A

Switzerland

Geochemistry & Geophysics, Geology, Paleontology ,

Hydrology , Geomorphology

Continental sediments and geomorphological features

of the coastal Wahiba Sands, Sultanate of Oman, reflect

environmental variability in southeastern Arabia

during the late Quaternary. Weakly cemented dune

sands, interdune deposits and coastal sediments

were dated by luminescence methods to establish an

absolute chronology of changes in sedimentary dynamics.

The dating results confirm previous assumptions

that during times of low global sea level sand

was transported by southerly winds from the exposed

shelf onto the Arabian Peninsula. Two prominent

phases of sand accumulation in the coastal area took

place just before and after the last glacial Maximum

(LGM). A final significant period of dune consolidation

is recognised during the early Holocene. However, no

major consolidation of dunes appears to have occurred

during the LGM and the Younger Dryas. In the

northern part of the Wahiba Sands, these two periods

are characterised by substantial sand deposition. This

discrepancy is explained by the lack of conservation

potential for dunes in the coastal area, probably

caused by a low groundwater table due to low sea

level and decreased precipitation. While the times of

aeolian activity reflect arid to hyper-arid conditions, lacustrine

and pedogenically altered interdune deposits

indicate wetter conditions than today caused by increased

monsoonal circulation during the Holocene

climatic optimum.

Journal of Quaternary Science, 2005, V20, N4, MAY,

pp 395-405

2 PAST GLOBAL CHANGES

05.3-164

Paleoclimatic significance of Early Holocene

faunal assemblages in wet interdune deposits of

the Wahiba Sand Sea, sultanate of Oman

Radies D, Hasiots S T, Preusser F, Neubert E, Matter A

Switzerland, USA, Germany

Paleontology , Zoology , Marine & Freshwater Biology

Invertebrate and trace fossil assemblages in wet interdune

deposits of the Wahiba Sand Sea record environmental

changes associated with the Indian Ocean

Monsoon system during the Early Holocene wet period.

This period is dated locally by infrared stimulated

luminescence (IRSL) from ca. 9300 to 5500 years

ago. Lacustrine deposits from interdune areas of the

central sand sea developed during peak precipitation

9300 years (IRSL) ago. The deposits represent shortlived

but permanent lakes characterized by salinity

tolerant freshwater snails and ostracodes. Diverse

trace fossils exposed on the present-day surface

show that the dried out lake sediments became substrates

for the dwelling, feeding, and reproductive activities

of insects. This period of continued moist conditions

with pronounced vegetation cover is recorded

in post-lacustrine, wet interdune deposits from the

coastal Wahiba Sand Sea. A 4-m thick succession of

interdune deposits was dated to ca. 8500-5500 years

(IRSL). This interdune succession shows intense bioturbation

by rhizocretions and insect burrows and

nests. Both sites of wet interdune deposits show that

changes of moist conditions during the Early

Holocene wet period can be monitored by a variety of

biological indicators. The ecological information of in

situ animal species and trace fossil assemblages

adds to the understanding how climatic changes are

expressed in continental environments.

Journal of Arid Environments, 2005, V62, N1, JUL,

pp 109-125

05.3-165

The last glacial/interglacial cycle at two sites in

the Chinese Loess Plateau: Mineral magnetic,

grain-size and Be-10 measurements and

estimates of palaeoprecipitation

Sartori M, Evans M E, Heller F, Tsatskin A, Han J M

Switzerland, Canada, Israel, Peoples R China

Geochemistry & Geophysics , Cryology / Glaciology ,

Ecology , Geomorphology , Paleontology ,

Meteorology & Atmospheric Sciences

To elucidate the way in which past climatic changes

are encoded magnetically by wind-blown silt, we have

investigated two stratigraphic sections in the Chinese

Loess Plateau (Xiagaoyuan, in the cool, dry western

Global Change Abstracts – The Swiss Contribution 77


plateau and Houzhuang, in the warmer, wetter central

plateau). In view of the anticipated importance of

magnetic particle size, we have determined grain-size

distributions from > 50 µm down to similar to 10 nm

by sequential sieving, sedimentation and centrifugation

of typical loess and palaeosol material from the

two sites. For the essentially unaltered loess, the

main susceptibility contribution lies in the 20-50 µm

fraction, with only similar to 20% of the signal residing

in the < 2 µm fraction. In the well-developed palaeosol,

similar to 60% of the susceptibility comes from

the < 2 gm fraction, with a strong peak in the 0.1-0.4

µm fraction. Low-temperature experiments confirm

this magnetic enhancement, and also exhibit Verwey

transitions characteristic of magnetite. Magnetic hysteresis

parameters show simple relationships to susceptibility,

which can be interpreted in terms of a uniform

mineral ingredient which increases in amount as

pedogenesis intensifies. Beryllium-10 content was determined

for a profile spanning palaeosol S-1 (corresponding

to oxygen isotope stage 5) at Houzhuang,

and a peak value of 4.8 x 10(8) atoms/g was observed,

almost identical to that found by other workers

for the same horizon at Luochuan, A similar profile at

Xiagaoyuan reveals three peaks corresponding to

palaeosols S1S1, (2.6 x 10(8) atoms/g), S1S2 (3.3 x

10(8) atoms/g) and S1S3 (3.3 x 10(8) atoms/g). Conversion

of these concentrations into Be-10 fluxes indicates

low dust accumulation during warmer climate

episodes. At these times pedogenic susceptibility enhancement

is favoured, the amounts of which imply

palaeoprecipitation slightly higher than today for S1S3

at Xiagaoyuan, but somewhat lower than today for S-

1 at Houzhuang.

Palaeogeography Palaeoclimatology Palaeoecology,

2005, V222, N1-2, JUN 21, pp 145-160

05.3-166

A record of the Jurassic/Cretaceous boundary

climatic variation on the southern margin of the

Tethys : clay minerals and palynofacies of the

early Cretaceous Jebel Meloussi section (Central

Tunisia, Sidi Kralif Formation)

Schnyder J, Gorin G, Soussi M, Baudin F,

Deconinck J F

France, Switzerland, Tunisia

Meteorology & Atmospheric Sciences , Limnology ,

Geochemistry & Geophysics

In order to precise the paleogeographic extension of

the climatic variation known at the Jurassic/Cretaceous

boundary, the sedimentary organic matter (palynofacies

and Rock-Eval) and the clay minerals content

of Berriasian sediments of the Sidi Kralif Formation

are studied on the Jebel Meloussi section, central

Tunisia. Standard sedimentological and palynofacies

analysis allow to reconstruct the bathymetric curve

and the sequence stratigraphic scheme. Using existing

biostratigraphy based on calpionellids and ammonite

zonation, the sequence stratigraphic interpre-

78

Global Change Abstracts – The Swiss Contribution

2 PAST GLOBAL CHANGES

tation can be correlated with the established eustatic

chart. Clay mineral assemblages are characterized by

a shift in the kaolinite content, recorded at the end of

the calpionellid zone B, at the early/middle Berriasian

boundary, at a time of high long-term sea-level (MFS

Be2, second order eustatic peak). A contemporary

change in the clay mineral assemblages, interpreted

as a climatic change, is known from the boreal area,

and from the northern margin of the Tethys Sea. That

change is also documented southerly in southern Morocco

(Agadir area) , on the Atlantic domain. A late

Tithonian to early Berriasian dry and cooler phase is

replaced by a middle to late Berriasian more humid

phase, indicated by a general increase in kaolinite in

the clay mineral assemblages. The trend from a dry

climatic phase to a more humid one, recorded on the

boreal domain and along the northern margin of the

Tethys is also recorded in lower paleolatitudes of

Tunisia, on the southern margin of the Tethys, in better

dated outcrops than the ones of Morocco. The results

obtained in Tunisia show that the beginning of

the climatic change was precisely synchronous on

both margins, and occurred within the same long-term

high sea-level context.

Bulletin de la Societe Geologique de France, 2005,

V176, N2, pp 171-182

05.3-167

Analyzing rockfall activity (1600-2002) in a

protection forest - a case study using

dendrogeomorphology

Stoffel M, Schneuwly D, Bollschweiler M, Lievre I,

Delaloye R, Myint M, Monbaron M

Switzerland

Geomorphology , Forestry , Geology , Paleontology

For the first time, dendrogeomorphology has been

used to investigate spatial and temporal variations of

rockfall activity in a protection forest. We report results

of 564 cores from 135 severely injured Larix decidua

Mill. trees on the west-facing Taschgufer slope,

Swiss Alps. While trees sampled reached an age of

297 years on average, the oldest one attained breast

height in AD 1318. For reasons of sample depth, the

analysis was limited to the period 1600-2002. In total,

we reconstructed 741 growth disturbances (GD) during

the last four centuries. Impacts were most commonly

found in trees located in the southern part of

the slope, where GD recurred more than once per

decade. In contrast, trees in the northern part were

less frequently disturbed by rockfall and define recurrence

intervals of more than 150 years. Throughout

the last four centuries, rockfall has caused GD to the

trees sampled on the Taschgufer slope, most frequently

in the form of low magnitude-high frequency

events. In addition, we identified one high magnitudelow

frequency event in 1720, which displaced the forest

fringe of the northern sector a considerable distance

downslope and eliminated an entire forest

stand. To analyze past rockfall activity, we introduce a


"rate" defined as the number of impacts per meter

width of all tree surfaces sampled per decade. Results

clearly demonstrate that this rockfall "rate" continually

decreased in both sectors after the large 1720

rockfall event. Significantly low rockfall "rates" can be

observed during the 1850s, 1960s and 1970s in the

northern and during the 1820s in the southern sector.

In contrast, high rockfall "rates" were identified during

the 1870s and 1990s in the northern, and during the

1770s in the southern sector. Reconstructed data further

show that the forest recolonizing the southern

sector after the 1720 event gradually improved its protective

function, reducing "rates" by a factor of 13 between

the 1740s and the 1990s. In the recent past,

"rates" oscillated around 0.7 GD 1 meter width(-1) (10

years)(-1). In the well-established forest of the northern

sector, the efficacy of the protective forest was

temporarily reduced by the rockfalls in 1720, resulting

in increased rockfall "rates". Since then, the protective

function of the forest stand has increased again, resulting

in a rate of 0.4 GD 1 m width(-1) (10 years)(-1)

during the late 20th century.

Geomorphology, 2005, V68, N3-4, JUN 1, pp 224-241

05.3-168

Late-glacial glacier events in southernmost South

America: A blend of 'northern'and 'southern'

hemispheric climatic signals?

Sugden D E, Bentley M J, Fogwill C J, Hulton N R J,

Mcculloch R D, Purves R S

Scotland, England, Switzerland

Cryology / Glaciology , Geochemistry & Geophysics ,

Geomorphology , Meteorology & Atmospheric

Sciences , Paleontology , Modelling

This paper examines new geomorphological, chronological

and modelling data on glacier fluctuations in

southernmost South America in latitudes 46-55 degrees

S during the last glacial-interglacial transition.

Establishing leads and lags between the northern and

southern hemispheres and between southern mid-latitudes

and Antarctica is key to an appreciation of the

mechanisms and resilience of global climate. This is

particularly important in the southern hemisphere

where there is a paucity of empirical data. The overall

structure of the last glacial cycle in Patagonia has a

northern hemisphere signal. Glaciers reached or approached

their Last Glacial Maxima on two or more

occasions at 25-23 ka (calendar) and there was a

third less extensive advance at 17.5 ka. Deglaciation

occurred in two steps at 17.5 ka and at 11.4 ka. This

structure is the same as that recognized in the northern

hemisphere and taking place in spite of glacier

advances occurring at a time of high southern hemisphere

summer insolation and deglaciation at a time

of decreasing summer insolation. The implication is

that at orbital time scales the 'northern' signal dominates

any southern hemisphere signal. During

deglaciation, at a millennial scale, the glacier fluctuations

mirror an antiphase 'southern' climatic signal as

2 PAST GLOBAL CHANGES

revealed in Antarctic ice cores. There is a glacier advance

coincident with the Antarctic Cold Reversal at

15.3-12.2 ka. Furthermore, deglaciation begins in the

middle of the Younger Dryas. The implication is that,

during the last glacial-interglacial transition, southernmost

South America was under the influence of sea

surface temperatures, sea ice and southern westerlies

responding to conditions in the 'southern' Antarctic

domain. Such asynchrony may reflect a situation

whereby, during deglaciation, the world is more sensitized

to fluctuations in the oceanic thermohaline circulation,

perhaps related to the bipolar seesaw, than at

orbital timescales.

Geografiska Annaler Series A Physical Geography,

2005, V87A, N2, pp 273-288

05.3-169

Solving the paradox of the end of the Little Ice

Age in the Alps

Vincent C, Le Meur E, Six D, Funk M

France, Switzerland

Meteorology & Atmospheric Sciences , Cryology /

Glaciology , Paleontology

The causes and timing of the Little Ice Age ( fifteenth

to nineteenth centuries) are still unclear (Crowley,

2000; Bond et al., 2001; Shindell et al., 2001). During

the last part of this event ( 1760 - 1830), the advance

of glaciers in the Alps conflicts with the summer temperature

signal ( Intergovernmental Panel on Climate

Change, 2001) . This paper attempts to solve this

paradox. From glacier fluctuations and monthly temperature

data, we show that mean winter precipitation

was higher by at least 25% during this final phase

compared to the twentieth century average and that

glacier recession after 1830 clearly resulted from a

winter precipitation decrease and not a temperature

increase. Conversely, since the beginning of the twentieth

century, glacier changes have been driven mainly

by temperature change.

Geophysical Research Letters, 2005, V32, N9,

MAY 13, ARTN: L09706

05.3-170

A 500 year dendroclimatic reconstruction of

spring-summer precipitation from the lower

Bavarian Forest region, Germany

Wilson R J S, Luckman B H, Esper J

Scotland, Canada, Switzerland

Forestry , Plant Sciences , Paleontology , Meteorology

& Atmospheric Sciences , Modelling , Hydrology

This paper presents a 500 year March-August precipitation

reconstruction for the Bavarian Forest region of

southeast Germany based on a composite well-replicated

data set of 676 living and historical tree-ring

width series from Norway spruce. Two versions of the

Global Change Abstracts – The Swiss Contribution 79


chronology are developed. The cubic smoothing

spline (SPL) chronology, standardized with a fixed 80

year spline function, retains decadal and higher frequency

variation. The regional curve standardization

(RCS) chronology uses regional curve standardization

to retain additional lower frequency variation from the

same data. Calibration V(1879-1978) of these

chronologies with March-August precipitation indicates

they explain 40% (SPL) and 34% (RCS) of the

variability in the instrumental precipitation record. The

SPL reconstruction models the high-frequency variation

better, whereas the RCS reconstruction tracks the

low-frequency trends more robustly. It suggests that

spring-summer precipitation was above the long-term

average for the periods 1730-1810 and 1870-2000,

about average between 1560 and 1610 and that significantly

drier periods occurred during 1510-60,

1610-35, 1660-1730 and 1830-70. The low-frequency

trends of the RCS reconstruction during the 19th century

were verified by comparison with a regional precipitation

series derived from 14 long precipitation

05.3-171

Jevons' paradox

Alcott B

Switzerland

Economics , Social Sciences , Political Sciences

In The Coal Question William Stanley Jevons

(Jevons, W.S., 1865/1965. The Coal Question: an Inquiry

Concerning the Progress of the Nation, and the

Probable Exhaustion of our Coal-mines. 3rd edition

1905, Ed. A.W. Flux. Augustus M. Kelley, New York.)

maintained that technological efficiency gains-specifically

the more "economical" use of coal in engines doing

mechanical work-actually increased the overall

consumption of coal, iron, and other resources, rather

than "saving" them, as many claimed. Twentieth-century

economic growth theory also sees technological

change as the main cause of increased production

and consumption. In contrast, some ecologically-oriented

economists and practically all governments,

green political parties and NGOs believe that efficiency

gains lower consumption and negative environmental

impact. Others doubt this 'efficiency strategy'

towards sustainability, holding that efficiency gains 'rebound'

or even 'backfire' in pursuing this goal, causing

higher production and consumption. Because many

environmental problems demand rapid and clear policy

recommendations, this issue deserves high priority

in ecological economics. If Jevons is right, efficiency

policies are counter-productive, and business-as-usu-

80

2 PAST GLOBAL CHANGES / 3 HUMAN DIMENSIONS

Global Change Abstracts – The Swiss Contribution

3 Human Dimensions

records from central Europe. Better verification results

were obtained using the original (non- homogenized)

records over this interval. These results suggest that

some low-frequency variability may have been removed

during correction of these early records. Periods

of synchronous decadal variability were observed

between the SPL series and independent dendroclimatic

reconstructions from central Europe. The RCS

reconstruction is the first dendroclimatic precipitation

reconstruction in Europe to capture low-frequency information.

These lone-term trends, however, are difficult

to verify owing to the paucity of other proxy precipitation

records in central Europe that portray lowfrequency

information. Further verification and testing

of the RCS reconstruction will require the development

of additional reconstructions from tree-rings (or

other proxy data series) that similarly target loss-frequency

variability.

International Journal of Climatology, 2005, V25, N5,

APR, pp 611-630

al efficiency gains must be compensated for with

physical caps like quotas or rationing.

Ecological Economics, 2005, V54, N1, JUL 1, pp 9-21

05.3-172

Human health, well-being, and global ecological

scenarios

Butler C D, Corvalan C F, Koren H S

Australia, Switzerland, USA

Human & Public Health , Ecology

This article categorizes four kinds of adverse effects

to human health caused by ecosystem change: direct,

mediated, modulated, and systems failure. The effects

are categorized on their scale, complexity, and lagtime.

Some but not all of these can be classified as

resulting from reduced ecosystem services. The articles

also explores the impacts that different socioeconomic-ecologic

scenarios are likely to have on human

health and how changes to human health may, in

turn, influence the unfolding of four different plausible

future scenarios. We provide examples to show that

our categorization is a useful taxonomy for understanding

the complex relationships between ecosystems

and human well-being and for predicting how future

ecosystem changes may affect human health.

Ecosystems, 2005, V8, N2, MAR, pp 153-162


05.3-173

The global burden of disease due to outdoor air

pollution

Cohen A J, Anderson H R, Ostro B, Pandey K D,

Krzyzanowski M, Künzli N, Gutschmidt K, Pope A,

Romieu I, Samet J M, Smith K

USA, England, Germany, Switzerland, Mexico

Human & Public Health , Meteorology & Atmospheric

Sciences

As part of the World Health Organization (WHO)

Global Burden of Disease Comparative Risk Assessment,

the burden of disease attributable to urban ambient

air pollution was estimated in terms of deaths

and disability-adjusted life years (DALYs). Air pollution

is associated with a broad spectrum of acute and

chronic health effects, the nature of which may vary

with the pollutant constituents. Particulate air pollution

is consistently and independently related to the most

serious effects, including lung cancer and other cardiopulmonary

mortality. The analyses on which this

report is based estimate that ambient air pollution, in

terms of fine particulate air pollution (PM2.5), causes

about 3% of mortality from cardiopulmonary disease,

about 5% of mortality from cancer of the trachea,

bronchus, and lung, and about 1% of mortality from

acute respiratory infections in children under 5 yr,

worldwide. This amounts to about 0.8 million (1.2%)

premature deaths and 6.4 million (0.5%) years of life

lost (YLL). This burden occurs predominantly in developing

countries; 65% in Asia alone. These estimates

consider only the impact of air pollution on mortality

(i.e., years of life lost) and not morbidity (i.e., years

lived with disability), due to limitations in the epidemiologic

database. If air pollution multiplies both incidence

and mortality to the same extent (i.e., the same

relative risk), then the DALYs for cardiopulmonary disease

increase by 20% worldwide.

Journal of Toxicology and Environmental Health Part

A Current

05.3-174

Personal exposures to VOC in the upper end of

the distribution - relationships to indoor, outdoor

and workplace concentrations

Edwards R D, Schweizer C, Jantunen M, Lai H K,

Bayer Oglesby L, Katsouyanni K, Nieuwenhuijsen M,

Saarela K, Sram R, Künzli N

USA, Switzerland, Finland, England, Greece,

Czech Republic

Human & Public Health , Meteorology & Atmospheric

Sciences

Evaluation of relationships between median residential

indoor, indoor workplace and population exposures

may obscure potential strategies for exposure

reduction. Evaluation of participants with personal exposures

above median levels in the EXPOLIS study in

Athens, Helsinki, Oxford and Prague illustrated that

3 HUMAN DIMENSIONS

these participants frequently showed a different relationship

to indoor and workplace levels than that

shown by the population median. Thus, prioritization

of environments for control measures based on median

exposures may exclude important areas where effectively

focused control measures are possible, and

may therefore have little impact on the highest and

most harmful exposures. Further, personal exposures

at the upper end of the distribution may exceed the

US EPA inhalation reference concentration (Rfc), illustrated

here using hexane, naphthalene and benzene.

For example upper 90th percentile personal exposures

to benzene in Athens and Prague were 64 and

27 μ g m(-3) with peak exposures of 217 and 38

μ g m(-3), respectively for non-ETS exposed participants

relative to an Rfc of 30 μ g m(-3). Strategies

to reduce exposures to individual compounds,

therefore, may benefit from focus on the high end of

the distribution to identify activities and behaviors that

result in elevated exposures. Control strategies targeting

activities that lead to exposures in the upper

end of the distribution would reduce the variability associated

with population median values by bringing

the upper end of the exposure distribution closer to

median values. Thus, compliance with health-based

standards would be more protective of the higher exposed

fraction of the population, in whom health effects

would be more expected.

Atmospheric Environment, 2005, V39, N12, APR,

pp 2299-2307

05.3-175

Prioritizing long-term watershed management

strategies using group decision analysis

Ghanbarpour M R, Hipel K W, Abbaspour K C

Canada, Iran, Switzerland

Water Resources , Social Sciences , Political

Sciences

There is a growing consensus that an effective way of

enhancing long- term water resources management

and environmental sustainability is through locally

based planning at the watershed scale. Managing watershed

resources for particular uses requires interactive

dialogue among all stakeholders who have different

objectives. Therefore, the resolution of inter-group

conflict should be an acknowledged task of the planning

process. In this paper, an integrated framework

for prioritizing watershed management strategies is

proposed. A case study is employed to highlight the

challenges of using group decision analysis in strategic

planning and to illustrate the interaction between

different stakeholders on watershed issues. In particular,

two group decision-making approaches are used

to assess and analyse different stakeholders' preferences

for various strategies and alternatives. Professional

experts, government agencies and community

leaders constitute the different parties included in the

framework. The main focus is on the application of

group decision analysis in the long-term watershed

Global Change Abstracts – The Swiss Contribution 81


planning process. The results of the overall preference

analysis show that water resources development

is the most important strategy followed by agricultural

and range management.

International Journal of Water Resources Development,

2005, V21, N2, JUN, pp 297-309

05.3-176

Risk perception of heavy metal soil contamination

by high-exposed and low-exposed inhabitants:

The role of knowledge and emotional concerns

Grasmuck D, Scholz R W

Switzerland

Agriculture, Soil Sciences , Human & Public Health ,

Social Sciences , Education , Psychology

Soil contaminated with heavy metals is a salient example

of environmental risk. Consumption of vegetables

cultivated in contaminated soil or direct ingestion

of soil by small children can damage health. In contrast

to other kinds of pollution or risks such as air pollution

or exposure to ozone, the individual risk concerning

soil contamination is highly dependent on the

way one is exposed to the local source of risk. Thus,

we wanted to know if risk perception varies according

to the level of exposure. A quasi-experimental, questionnaire-based

study was conducted in a community

in northwest Switzerland, where the soil is widely contaminated.

The level of contamination varies with the

distance from the source of the contamination, a metal

processing plant. We investigated the perception of

risk of heavy-metal-contaminated soil by inhabitants

with high-exposure levels (N= 27) and those with lowexposure

levels (N= 30). Both groups judged the risk

for oneself similarly whereas the low-exposure group,

when compared to the high-exposure group, judged

perceived risk for other affected people living in their

community to be higher. Besides this exposure effect,

risk perception was mainly determined by emotional

concerns. Participants with higher scores in self-estimated

knowledge tended to provide low-risk judgments,

were less interested in further information,

showed low emotional concern, and thus displayed

high risk acceptance. In contrast, actual knowledge

showed no correlation with any of theses variables.

Judgments on the need for decontamination are determined

by risk perception, less application of dissonance-reducing

heuristics and commitment to sustainability.

The desire for additional information is not affected

by missing knowledge but is affected by emotional

concerns.

Risk Analysis, 2005, V25, N3, JUN, pp 611-622

05.3-177

Heat wave 2003 and mortality in Switzerland

Grize L, Huss A, Thommen O, Schindler C, Braun

Fahrländer C

82

Global Change Abstracts – The Swiss Contribution

3 HUMAN DIMENSIONS

Switzerland

Human & Public Health , Meteorology & Atmospheric

Sciences

Questions under study: During June to August 2003,

high temperatures were reported across Europe including

Switzerland. In many European countries,

particularly in France the heat wave was associated

with an increase in mortality. This is the first analysis

investigating whether the high temperatures during

summer 2003 in Switzerland had a measurable impact

on mortality. Methods: Daily data on all-cause

mortality for the period January 1990 to December

2003, and meteorological data from 20 different stations

for the same period were analysed. Excess mortality

for different age groups, gender and geographic

regions was calculated. Daily mortality and temperature

in 2003 was correlated with lags of temperature

up to 7 days. Results: An estimated 7% increase in all

cause mortality occurred during June to August 2003.

Excess mortality was limited to the region north of the

Alps, to inhabitants of cities and suburban areas and

was more pronounced among the elderly and the inhabitants

of Basel, Geneva and Lausanne. North of

the Alps, deviations in daily mortality were significantly

correlated with deviations in maximum daily temperatures

and night temperatures. The combination of day

temperature above 35 degrees C and night temperatures

above 20 degrees C predominantly occurred in

Basel and Geneva and might in part explain the regional

differences in excess mortality. Conclusions: As

the number of elderly people in Switzerland continues

to rise and the occurrence of heat waves is predicted

to increase as a consequence of global warming, preventive

programmes targeting susceptible populations

during heat waves are warranted.

Swiss Medical Weekly, 2005, V135, N13-14, APR 2,

pp 200-205

05.3-178

Agri-environment schemes as landscape

experiments - Preface

Herzog F

Switzerland

Agriculture, Soil Sciences , Political Sciences

Agri-environment schemes are payments to farmers

to address environmental problems. More than 300

different policy measures are implemented in the

member countries of the Organisation for Economic

Co-operation and Development (OECD), mostly addressing

water, biodiversity and landscape protection.

About 20% of the farmland of the European Union are

under some form of agri-environment scheme. These

schemes can be regarded as landscape experiments

because semi- natural biotopes are being deliberately

introduced and matter (nutrients, pesticides) and energy

flows are manipulated. Their evaluation, however.

is methodologically difficult and the few existing

studies are controversial. More research on agri-envi-


onment schemes is needed to assess and improve

their effectiveness.

Agriculture Ecosystems Environment, 2005, V108,

N3, JUN 30, pp 175-177

05.3-179

Reconsidering the risk assessment concept:

Standardizing the impact description as a building

block for vulnerability assessment

Hollenstein K

Switzerland

Modelling , Meteorology & Atmospheric Sciences

Risk assessments for natural hazards are becoming

more widely used and accepted. Using an extended

definition of risk, it becomes obvious that performant

procedures for vulnerability assessments are vital for

the success of the risk concept. However, there are

large gaps in knowledge about vulnerability. To alleviate

the situation, a conceptual extension of the scope

of existing and new models is suggested. The basis of

the suggested concept is a stadardization of the output

of hazard assessments. This is achieved by defining

states of the target objects that depend on the impact

and at the same time affect the object's performance

characteristics. The possible state variables

can be related to a limited set of impact descriptors

termed generic impact description interface. The concept

suggests that both hazard and vulnerability assessment

models are developed according to the

specification of this interface, thus facilitating modularized

risk assessments. Potential problems related to

the application of the concept include acceptance issues

and the lacking accuracy of transformation of

outputs of existing models. Potential applications and

simple examples for adapting existing models are

briefly discussed.

Natural Hazards and Earth System Sciences, 2005,

V5, N3, pp 301-307

05.3-180

A call for reporting the relevant exposure term in

air pollution case-crossover studies

Künzli N, Schindler C

Switzerland

Meteorology & Atmospheric Sciences , Human &

Public Health

The exposure term in the case- crossover design consists

in the difference between the ambient concentration

on the event day and the concentration(s) on

some control day( s). So far, all air pollution casecrossover

studies presented the distribution of the

daily ambient pollutant concentrations but do not pub-

3 HUMAN DIMENSIONS

lish the distributional properties of the relevant exposure

term - that is, the concentration difference. This

article shows that this difference can be very small for

a large fraction of event days, therefore, seriously limiting

the statistical power to refute the null hypothesis.

Publishing the distribution of the relevant differences

will improve the interpretation and discussion of findings

from case- crossover studies, particularly in cases

with statistically non- significant associations.

Journal of Epidemiology and Community Health,

2005, V59, N6, JUN, pp 527-530

05.3-181

Energy in the perspective of the sustainable

development: The 2000 W society challenge

Marechal F, Favrat D, Jochem E

Switzerland, Germany

Energy & Fuels , Social Sciences , Political Sciences ,

Education

As energy plays a central role in the world development,

it represents as well a major challenge for sustainable

development. Today, more than 80% of the

primary energy consumption is based on fossil fuels

and the share is likely to remain high in the future.

Even if technology developments will reduce the specific

consumption, the world energy demand is likely

to increase in line with its population. Energy and material

efficiency and the integration of the renewable

resources will therefore have to play a major role for

sustainable development. The challenge concerns not

only the technologies at the conversion and useful energy

level, but also the energy management and infrastructures.

The 2000 W per capita society initiative

launched by the Board of the Swiss Institutes of Technology

targets the identification of the major technological

breakthroughs to reduce the per capita primary

energy use of Switzerland by two-thirds within five

decades. This study examined the energy saving potentials

in the complete conversion chain "from primary

energy to energy services" in the main sectors of

economy: buildings, transport and industry. The report

highlights the possible benefits which could be obtained

from new materials, new technologies and an

intensification of product and capital use. The systems

integration appeared to be of prime importance

in order to valorise the exergy potentials of the energy

resources. The report emphasizes the political responsibility

of developing the enabling society infrastructure:

not only for the energy distribution (electrical,

gas or heating networks) but also for the information

technology, the appropriate regulations, the education

and for the necessary integration of the lifetimes of

the manufactured artifacts in the pathway to the 2000

W per capita society.

Resources Conservation and Recycling, 2005, V44,

N3, JUN, pp 245-262

Global Change Abstracts – The Swiss Contribution 83


05.3-182

Statistical analysis of CDM capacity-building

needs

Nondek L, Arquit Niederberger A

USA, Switzerland

Political Sciences

This article presents statistical analysis of a selection

of data collected under a World Bank survey on Kyoto

Protocol capacity-building needs in 16 potential clean

development mechanism (CDM) host countries. It focuses

on three interrelated issues: perceived barriers

to the implementation of the CDM, expert judgment

regarding the human, institutional and systemic capacity

that must be built to overcome these barriers,

and views on the most urgent steps that need to be

taken to facilitate CDM implementation. The analysis

reveals that in many countries there is a wide diversity

of opinion across the group of respondents, which

could be caused by a number of factors, including the

inherent complexity of the Kyoto flexible mechanisms,

limited understanding of their basic functioning and

potential in the local context, and the differing needs

and interests of stakeholder groups. Despite this,

many statistically significant preferences can be identified

at the national level. Among nations, two broad

groups of countries emerge, which can be traced

back to their overall level of capacity development.

The statistical analysis presented in this article lends

credibility to qualitative conclusions drawn from previous

interpretations of the survey data and has implications

for the design of capacity-building efforts.

However, in evaluating capacity-building needs and

the readiness of countries to engage in CDM deals,

potential investors and providers of capacity-building

services will need to consider not only the results of

this type of opinion- based needs assessment, but

also the practical experience gained through CDM

transactions.

Climate Policy, 2005, N4, pp 249-268

05.3-183

Policy principles and implementation guidelines

for private sector participation in the water sector

- a step towards better results

Rothenberger D, Frei U, Brugger F

Switzerland

Political Sciences , Water Resources

To achieve the Millennium Development Goals, all

partners (public, private, NGOs) must be engaged for

improving and expanding the water supply and sanitation

services. Yet, high transaction costs, unclear role

allocation and lack of trust and commitment put Private

Sector Participation (PSP) at risk. The initiative

"Policy Principles and Implementation Guidelines for

Private Sector Participation in Sustainable Water Supply

and Sanitation" contributes to equitable, effective,

ecological and efficient PSP projects. Based on a mul-

84

Global Change Abstracts – The Swiss Contribution

3 HUMAN DIMENSIONS

ti stakeholder process, the Policy Principles are offering

an open and transparent framework for the negotiation

of valid, widely accepted and action-oriented solutions,

while the Implementation Guidelines focus on

success factors for building partnerships on the operational

level.

Water Science and Technology, 2005, V51, N8,

pp 61-69

05.3-184

Distribution of energy consumption and the

2000 W/capita target

Spreng D

Switzerland

Energy & Fuels

This viewpoint discusses the intra- and international

distribution of energy consumption and their implications

for intergenerational equity. For global development

to be sustainable, the inequality of energy consumption

must have ail upper limit. A graphic depiction

of energy consumption distributions (intra- and international)

shows that today's inequalities are large

and it is argued that we may have already reached or

perhaps even Surpassed the sustainability limit of energy

consumption inequality.

Energy Policy, 2005, V33, N15, OCT, pp 1905-1911

05.3-185

Between conservation and development -

Concretizing the first World Natural Heritage Site

in the Alps through participatory processes

Wiesman U, Liechti K, Rist S

Switzerland

Social Sciences , Political Sciences

This article presents an empirical interdisciplinary

study of an extensive participatory process that was

carried out in 2004 in the recently established World

Natural Heritage Site "Jungfrau-Aletsch- Bietschhorn"

in the Swiss Alps. The study used qualitative and

quantitative empirical methods of social science to address

the question of success factors in establishing

and concretizing a World Heritage Site. Current international

scientific and policy debates agree that the

most important success factors in defining pathways

for nature conservation and protection are: linking development

and conservation, involving multiple stakeholders,

and applying participatory approaches. The

results of the study indicate that linking development

and conservation implies the need to extend the

reach of negotiations beyond the area of conservation,

and to develop both a regional perspective and a

focus on sustainable regional development. In the

process, regional and local stakeholders are less concerned

with defining sustainability goals than elaborating

strategies of sustainability, in particular defining


the respective roles of the core sectors of society and

economy. However the study results also show that

conflicting visions and perceptions of nature and landscape

are important underlying currents in such negotiations.

They differ significantly between various

stakeholder categories and are an important cause of

conflicts occurring at various stages of the participatory

process.

Mountain Research and Development, 2005, V25,

N2, MAY, pp 128-138

05.3-186

3 HUMAN DIMENSIONS / 4 MITIGATION AND ADAPTATION TECHNOLOGIES

Towards sustainable land use: identifying and

managing the conflicts between human activities

and biodiversity conservation in Europe

Young J, Watt A, Nowicki P, Alard D, Clitherow J,

Henle K, Johnson R, Laczko E, Mccracken D,

Matouch S, Niemela J, Richards C

Scotland, France, Germany, Sweden, Switzerland,

Finland

Agriculture, Soil Sciences , Social Sciences ,

Biodiversity , Education , Political Sciences

05.3-187

Towards accurate instantaneous emission models

Ajtay D, Weilenmann M, Soltic P

Switzerland

Engineering , Meteorology & Atmospheric Sciences ,

Modelling , Energy & Fuels

To address the needs of researchers and policy makers

on local levels, a microscopic (i.e. at vehicle level)

instantaneous emission model is being developed.

This model aims to predict vehicle fuel consumption

and emissions for a given speed profile, for various

vehicle loads, slopes and gear shift scenarios. Instantaneous

emission modelling maps the emissions at a

given time to their generating "engine state". To improve

the existing models, an analysis of some preconditions

must be made: owing to the frequency content

of the engine and emission signals, they should

be measured on a 10 Hz basis or faster. Additionally,

the emission signals measured in a test are delayed

dynamically, owing to the transport from the engine to

the analysers. This transport must be compensated

for by time-varying approaches. The modelling and

compensation for the gas transport in dilution systems

is presented here. With these preconditions fulfilled,

Conflicts between biodiversity conservation and human

activities are becoming increasingly apparent in

all European landscapes. The intensification of agricultural

and silvicultural practices, land abandonment

and other land uses such as recreation and hunting

are all potential threats to biodiversity that can lead to

conflicts between stakeholder livelihoods and biodiversity

conservation. To address the global decline in

biodiversity there is, therefore, a need to identify the

drivers responsible for conflicts between human activities

and the conservation of European biodiversity

and to promote the management of these conflicts.

Here, the drivers of biodiversity conflicts are analysed

in a European context for. five habitat types: agricultural

landscapes, forests, grasslands, uplands and

freshwater habitats. A multi-disciplinary approach to

conflict management is described, with active stakeholder

involvement at every stage of conflict identification

and management as well as a range of other

approaches including stakeholder dialogue and education,

consumer education, improvement of political

and legislative frameworks,. financial incentives, and

planning infrastructure.

Biodiversity and Conservation, 2005, V14, N7, JUN,

pp 1641-1661

4 Mitigation and Adaptation Technologies

new instantaneous emission models are developed

and their improvement in quality is checked by comparing

them with older models. Further improvements

to describe the transient emissions of vehicles are

sketched.

Atmospheric Environment, 2005, V39, N13, APR,

pp 2443-2449

05.3-188

Physical characterization of particulate emissions

from diesel engines: a review

Burtscher H

Switzerland

Engineering , Meteorology & Atmospheric Sciences ,

Energy & Fuels

Properties of particles emitted from diesel engines

and the consequences of these properties for sampling

and measuring the particles are reviewed. The

influence of aftertreatment devices such as particle

traps and catalytic converters on particle properties is

demonstrated. Based on the particle properties and

results from health effect studies, requirements to

Global Change Abstracts – The Swiss Contribution 85


metrics, and measurement systems, for example, for

type approval testing, are discussed. This discussion

is limited to physical properties. Special attention is

given to the volatile fraction. We show that care has to

be taken when designing the sampling and dilution

system, because this step decisively influences what

happens with the volatile material, which may remain

in the gas phase, condense on solid particles, or form

new particles by nucleation. If nucleation occurs, particles

formed in the sampling lines may dominate the

particle number concentration. A selection of systems

for dilution, conditioning and measuring is shown.

Systems to determine number, mass, and surface

concentrations, size distributions, and carbon concentration

are discussed. The discussion is focused on

systems developed or adapted recently for the physical

characterization of diesel particles.

Journal of Aerosol Science, 2005, V36, N7, JUL,

pp 896-932

05.3-189

The air membrane-ATR integrated gas turbine

power cycle: A method for producing electricity

with low CO2 emissions

Fiaschi D, Gamberi F, Bartlett M, Griffin T

Italy, Sweden, Switzerland

Energy & Fuels , Engineering

The air membrane-auto thermal reforming (AM-ATR)

gas turbine cycle combines features of the R-ATR

power cycle, introduced at the University of Florence,

with ceramic, air separation membranes to achieve a

novel combined cycle process with fuel decarbonisation

and near-zero CO2 emissions. Within this process,

the natural gas fuel is converted to H-2 and CO

through the auto thermal reforming process (ATR), i.e.

combined partial oxidation and steam methane reforming,

within the air separation membrane reactor.

In a subsequent process unit, the H-2 Content of the

reformed fuel is enriched by the well known CO-CO2

shift reaction. This fuel is then sent to an amine based

carbon dioxide removal unit and, finally, to two combustors:

the first one is located upstream of the membrane

reformer (in order to achieve the required working

temperature) and the second one is downstream

of the membrane to reach the desired turbine inlet

temperature (TIT). The main advantage of the proposed

concept over other decarbonisation processes

is the coupling of the membrane and the ATR reactor.

This coupling greatly reduces the mass flow of syngas

with respect to the air blown ATR contained in the previously

proposed R-ATR, thus lowering the size of the

syngas treatment section. Furthermore, as the oxygen

production is integrated at high temperatures in the

power cycle, the efficiency penalty of producing oxy-

86

4 MITIGATION AND ADAPTATION TECHNOLOGIES

Global Change Abstracts – The Swiss Contribution

gen is much smaller than for the traditional cryogenic

oxygen separation. The main advantages over other

integrated GT-membrane concepts are the lower

membrane operating temperature, lower levels of required

air separation at high partial pressure driving

forces (leading to lower membrane surface areas)

and the possibility to achieve a higher TIT with top firing

without increasing CO2 emissions. When compared

to power plants with tail end CO2 separation,

the CO2 removal process treats a gas at pressure and

with a significantly higher CO2 concentration than that

of gas turbine exhausts, which allows a compact carbon

dioxide removal unit with a lower energy penalty.

Starting from the same basis, various configurations

were considered and optimised, all of which targeted

a 65 MW power output combined cycle. The efficiency

level achieved is around 45% (including recompression

of the separated CO2), which is roughly 10% less

than the reference GT-CC plant (without CO2 removal).

A significant part of the efficiency penalty (4.3-

5.6% points) is due to the fuel reforming, whereas further

penalties come from the recompression units,

loss of working fluid through the expander and the

steam extracted for the ATR reactor and CO2 separation.

The specific CO2 emissions of the MCM-ATR are

about 120 kg CO2/kWh, representing 30% of the

emissions without CO2 removal. This may be reduced

to 10-15% with a better design of the shift reactors

and the CO2 removal unit. Compared to other concepts

with air membrane technology, such as the

AZEP concept, the efficiency loss is much greater

when used for fuel de-carbonisation than for previous

integration options.

Energy Conversion and Management, 2005, V46,

N15-16, SEP, pp 2514-2529

05.3-190

Greenhouse gas emission reduction options:

modeling and implications

Hirschberg S

Switzerland

Energy & Fuels , Modelling

This paper presents some selected analysis approaches

developed and applied in Switzerland in the

context of the analysis of Greenhouse Gas emissions

associated with energy systems. The studies address

both current and future energy systems. Furthermore,

results examples from the China Energy Technology

Program are provided, putting in perspective the climate

change issue and damages due to air pollution.

This is further illustrated by highlighting global risk

benefits of climate-friendly energy supply options.

Energy, 2005, V30, N11-12, SI, AUG-SEP, pp 2025-2041


05.3-191

FULLSPECTRUM: a new PV wave making more

efficient use of the solar spectrum

Luque A, Marti A, Bett A, Andreev V M, Jaussaud C,

van Roosmalen J A M, Alonso J, Rauber A, Strobl G,

Stolz W, Algora C, Bitnar B, Gombert A, Stanley C,

Wahnon P, Conesa J C, van Sark W G J H M,

Meijerink A, van Klink G P M, Barnham K, Danz R,

Meyer T, Luque Heredia I, Kenny R, Christofides C,

Sala G, Benitez P

Netherlands, Spain, Germany, Russia, France,

Switzerland, Scotland, England, Italy, Cyprus

Engineering , Energy & Fuels

The project FULLSPECTRUM - an Integrated Project

(IP) in the terminology of the European Commission -

pursues a better exploitation of the FULL solar SPEC-

TRUM by (1) further developing concepts already scientifically

proven but not yet developed and (2) by trying

to prove new ones in the search for a breakthrough

in photovoltaic (PV) technology. More specific

objectives are the development of. (a) III-V multijunction

cells (MJC), (b) solar thermo-photovoltaic (TPV)

converters, (c) intermediate band (IB) materials and

cells (IBC), (d) molecular-based concepts (MBC) for

full PV utilisation of the solar spectrum and (e) manufacturing

technologies (MFG) for novel concepts including

assembling. MJC technology towards 40% efficiency

will be developed using lower cost substrates

and high light concentration (up or above 1000 suns).

TPV is a concept with a theoretically high efficiency

limit because the entire energy of all the photons is

used in the heating process and because the nonused

photons can be fed back to the emitter, therefore

helping in keeping it hot. In the IBC approach, subbandgap

photons are exploited by means of an IB.

Specific IB materials will be sought by direct synthesis

suggested by material-band calculations and using

nanotechnology in quantum dot (QD) IBCs. In the development

of the MBC, topics such as the development

of two-photon dye cells and the development of

a static global (direct and diffuse) light concentrator by

means of luminescent multicolour dyes and QDs, with

the radiation confined by photonic crystals, will be

particularly addressed. MFG include optoelectronic

assembling techniques and coupling of light to cells

with new-optic miniconcentrators.

Solar Energy Materials and Solar Cells, 2005, V87,

N1-4, SI, MAY, pp 467-479

05.3-192

Sustainability-guided promotion of renewable

electricity generation

Madlener R, Stagl S

Switzerland, England

Energy & Fuels , Political Sciences , International

Relations , Economics , Social Sciences , Ecology

In recent years, the threat of global climate change,

high fuel import dependence, and rapidly rising elec-

4 MITIGATION AND ADAPTATION TECHNOLOGIES

tricity demand levels have intensified the quest for

more sustainable energy systems. This in turn has increased

the need for policy makers to promote electricity

generation from renewable energy sources.

Guaranteed prices coupled with a buy-back obligation

for electricity fed into the grid is a popular renewables

promotion instrument, especially in Europe. More recently,

driven mainly by electricity market liberalisation

efforts, quota targets for the share of renewables in

combination with tradable 'green' certificates (TGC)

have received considerable attention. TGC offer a

greater theoretical potential for economic efficiency

gains, due to price competition and the greater flexibility

assigned to the obliged parties. While guaranteed

prices and TGC schemes support the operation

of renewable energy technology systems, bidding

schemes for renewable energy generation capacity

are used to raise economic efficiency on the plant

construction side. All of these policy instruments suffer

from the shortcoming that they do not explicitly account

for the often widely varying environmental, social

and economic impacts of the technologies concerned.

In this paper, we propose a methodology for

the design of renewable energy policy instruments

that is based on integrated assessment. In particular,

we argue that using participatory multicriteria evaluation

as part of the design of renewable energy promotion

policies would make it possible: (1) to differentiate

the level of promotion in a systematic and transparent

manner according to their socio-ecological economic

impact, and (2) to explicitly account for the preferences

of stakeholders. A further problem of existing

TGC and bidding schemes is that diversity of supply

could be severely diminished, if few low-cost technologies

were allowed to dominate the renewable energy

market. To ensure a certain diversity of technologies,

our scheme suggests the use of different technology

bands for technologies that are relatively homogeneous

with respect to their maturity.

Ecological Economics, 2005, V53, N2, APR 15,

pp 147-167

05.3-193

Comparison of mass-based and non-mass-based

particle measurement systems for ultra-low

emissions from automotive sources

Mohr M, Lehmann U, Rutter J

Switzerland

Energy & Fuels , Engineering

Drastic reduction in particle emissions of diesel-powered

vehicles and new findings on the health impact

of particles raise the question of a more sensitive

measurement procedure. In this paper, 16 different

particle mass measurement systems are compared

on a diesel heavy-duty engine equipped with a particle

filter to investigate their feasibility for particle characterization

for future ultra-low concentration levels.

The group of instruments comprises mass-related

methods (filter methods, laser-induced incandescence,

photoacoustic detection, photoelectric charg-

Global Change Abstracts – The Swiss Contribution 87


ing, combined inertial and mobility sizing, opacity) as

well as non-mass-related methods (CPC, diffusion

battery, diffusion charger, ELPI, light scattering). The

instruments are compared on the basis of repeatability,

limit of detection, sensitivity, time resolution and

correlation with the regulated gravimetric filter

method, and elemental carbon fraction (EC). Several

time-resolved methods show good performance and

give reliable results. Opacimeters and light scattering,

however, reveal shortcomings at these low concentrations.

For all time-resolved advanced methods, poor

correlation with the regulated filter method is observed,

but most of them show good correlation with

the EC fraction of the particles. This outcome demonstrates

the crucial role of the sampling conditions for

measurement methods that do not exclude volatile

material from detection. A clear improvement in sensitivity

is observed when non-mass-based instruments

are applied (e.g., number or surface-related methods).

The results reveal that reliable measurement

methods exist for future measurement procedures.

However, a change in the measurement method will

lead to a discontinuity in the inventories, making it difficult

to compare the particle emissions from future

and past vehicle generations.

Environmental Science Technology, 2005, V39, N7,

APR 1, pp 2229-2238

05.3-195

Mountain climates and climatic change:

An overview of processes focusing on the

European Alps

Beniston M

Switzerland

Geomorphology , Meteorology & Atmospheric

Sciences

This contribution provides an overview of the intricacies

of mountain climates, particularly as they pertain

to the European Alps. Examples will be given of issues

that are related to climatic change as observed in the

Alps during the course of the 20th century, and some

of the physical mechanisms that may be responsible

for those changes. The discussion will then focus on

the problems related to assessing climatic change in

regions of complex topography, the potential shifts in

climate during the 21st century that the alpine region

may be subjected to, and the associated climate-generated

impacts on mountain environments.

Pure and Applied Geophysics, 2005, V162, N8-9,

AUG, pp 1587-1606

88

4 MITIGATION AND ADAPTATION TECHNOLOGIES / 5 GENERAL TOPICS

Global Change Abstracts – The Swiss Contribution

5 General Topics

05.3-194

Regulated and nonregulated diesel and gasoline

cold start emissions at different temperatures

Weilenmann M, Soltic P, Saxer C, Forss A M, Heeb N

Switzerland

Energy & Fuels , Meteorology & Atmospheric

Sciences , Engineering

The emissions of modern cars are usually reduced in

warm engine conditions by catalysts. Consequently

emissions are significantly higher during the cold

start, i.e. the warm-up phase of the car. The duration

of this period and the emissions produced during it

depend on the ambient temperature as well as on the

initial temperature of the car's systems. The cold start

emissions of Euro-3 gasoline cars, Euro-2 diesel cars

and old pre-Euro-I gasoline cars were investigated at

cold ambient temperatures. Since the goal was to get

real-world emissions, the measurements were done

with cars belonging to private owners taken straight

from the road with no maintenance. The chassis dynamometer

tests were carried out at +23, -7 and -

20&DEG; C. The test cycle employed is a representative

urban ride from a real-world driving behaviour

study. Besides the regulated pollutants, methane,

benzene and toluene were also measured online by

chemical ionisation mass spectrometry.

Atmospheric Environment, 2005, V39, N13, APR,

pp 2433-2441

05.3-196

Knowledge for sustainable development in the

Tajik Pamir Mountains

Breu T, Maselli D, Hurni H

Switzerland

Political Sciences , Agriculture, Soil Sciences

Initiating a process of informed decision making for

sustainable development requires the following: a) the

values and objectives to be pursued need to be negotiated

among all concerned stakeholders of a specific

territorial unit; b) these stakeholders should have access

to a comparable level of knowledge; and c) the

decisions taken and the subsequent actions initiated

should have a positive impact on all dimensions of

sustainability, In the remote Tajik Pamir mountains, a

special effort was made to fulfill the above 3 principles

by developing and applying a new methodological approach

to sustainable development. The paper presents

the results of a multi-year baseline study project

in which 10 sectors ranging from agriculture to natural

hazards were assessed by a transdisciplinary Swiss-

Tajik research team. This knowledge base was en-


hanced in a development strategy workshop that

brought together stakeholders from the local to the international

levels. The methodology applied was

found appropriate to initiate a broad reflection and negotiation

process among various stakeholder groups,

leading to a joint identification of possible measures to

be taken. Knowledge-and its enhancement through

the involvement of all stakeholder levels-appeared to

be an effective carrier of innovation and changes of

attitudes, thus containing the potential to effectively

contribute to sustainable development in marginalized

and resource-poor mountain areas.

Mountain Research and Development, 2005, V25,

N2, MAY, pp 139-146

05.3-197

Life-cycle inventory of waste solvent distillation:

Statistical analysis of empirical data

Capello C, Hellweg S, Badertscher B, Hungerbühler K

Switzerland

Engineering , Ecology , Water Resources ,

Geochemistry & Geophysics

Distillation is one of the most important processes in

the chemical industry. An environmental assessment

of distillation processes is difficult because of the

highly specific features of each distillation process.

Life-cycle inventory (LCI) information is therefore

scarce. The goal of this paper is to provide reliable

data ranges for inventory flows of waste solvent distillation

(i.e. amount of recovered distillate, consumption

of steam, electricity, nitrogen, cooling water and ancillary

product, and the generation of organic waste,

wastewater, and outlet air). For this purpose, we collected

data from approximately 150 waste solvent distillation

processes from chemical industry and analyzed

them statistically. The results of the statistical

analysis compose generic data ranges for each LCI

parameter. Where appropriate, the data of each LCI

parameter have been subdivided according to the distillation

technology or the waste solvent composition.

Additionally, probability distributions have been fitted

to the data of each LCI parameter, thus enabling

quantitative uncertainty analysis (e.g. Monte Carlo

Simulation). In a case study we illustrate the application

of the inventory data ranges according to situations

of differing data availability.

Environmental Science Technology, 2005, V39, N15,

AUG 1, pp 5885-5892

05.3-198

Life-cycle assessment in pesticide product

development: Methods and case study on two

plant-growth regulators from different product

generations

Geisler G, Hellweg S, Hofstetter T B, Hungerbühler K

Switzerland

5 GENERAL TOPICS

Agriculture, Soil Sciences , Plant Sciences

Environmental assessments in pesticide product development

are generally restricted to plant uptake and

emissions of active ingredients. Life-cycle assessment

(LCA) enables a more comprehensive evaluation

by additionally assessing the impacts of pesticide

production and application (e.g. tractor operations).

The use of LCA in the product development of pesticides,

in addition to the methods commonly applied, is

therefore advisable. In this paper a procedure for conducting

LCA in early phases of product development

is proposed. In a case study, two plant-growth regulators

from different product generations were compared

regarding their application in intensive production

of winter wheat. The results showed that the reduced

emissions from active ingredients of the newer

pesticide were compensated by higher impacts from

the production process. The authors draw the conclusion

that it is important to consider environmental objectives

in the procurement of precursors, in addition

to the classical goals of increasing the efficacy and reducing

the nontarget effects of pesticides. Moreover,

the case study showed that decisions based on uncertain

results in early stages of product development

may need to be revised in later stages, e.g. based on

investigations of pesticides' effects on crop yield.

Environmental Science Technology, 2005, V39, N7,

APR 1, pp 2406-2413

05.3-199

Uncertainty analysis in life cycle assessment

(LCA): Case study on plant-protection products

and implications for decision making

Geisler G, Hellweg S, Hungerbühler K

Switzerland

Plant Sciences , Political Sciences , Toxicology

Goal, Scope, and Background. Uncertainty analysis in

LCA is important for sound decision support. Nevertheless,

the actual influence of uncertainty on decision

making in specific LCA case-studies has only been little

studied so far. Therefore, we assessed the uncertainty

in an LCA comparing two plant-protection products.

Methods. Uncertainty and variability in LCI flows

and characterization factors (CML-baseline method)

were expressed as generic uncertainty factors and

subsequently propagated into impact scores using

Monte-Carlo simulation. Uncertainty in assumptions

on production efficiency for chemicals, which is of

specific interest for the case study, was depicted by

scenarios. Results and Discussion. Impact scores

concerning acidification, eutrophication, and global

warming display relatively small dispersions. Differences

in median impact scores of a factor of 1.6 were

sufficient in the case study for a significant distinction

of the products. Results of toxicity impact-categories

show large dispersions due to uncertainty in characterization

factors and in the composition of sum parameters.

Therefore, none of the two products was

Global Change Abstracts – The Swiss Contribution 89


found to be significantly environmentally preferable to

the other. Considering the case study results and inherent

characteristics of the impact categories, a tentative

rule of thumb is put forward that quantifies differences

in impact scores necessary to obtain significant

results in product comparisons. Conclusion. Published

LCA case-studies may have overestimated the

significance of results. It is therefore advisable to routinely

carry out quantitative uncertainty analyses in

LCA. If this is not feasible, for example due to time restrictions,

the rule of thumb proposed here may be

helpful to evaluate the significance of results for the

impact categories of global warming, acidification, eutrophication,

and photooxidant creation.

International Journal of Life Cycle Assessment, 2005,

V10, N3, pp 184-192

05.3-200

The implications of changes in population, land

use, and land management for surface runoff in

the upper Nile Basin area of Ethiopia

Hurni H, Tato K, Zeleke G

Switzerland, Ethiopia

Social Sciences , Agriculture, Soil Sciences ,

Hydrology

Much concern has been raised about population increase

in the highlands of Ethiopia and its potential to

decrease runoff from the upper Nile Basin to the lowland

countries of Sudan and Egypt. The present article

examines long-term data on population, land use,

land management, rainfall, and surface runoff rates

from small test plots (30 m(2)) and micro-catchments

(73-673 ha) in the highlands of Ethiopia and Eritrea.

Although the data were generated only on small areas,

the results of the analyses can nevertheless be

used to draw some conclusions relevant to the highland-lowland

water controversies that have persisted

in this particular regio