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Methods of assessment of direct<br />

<strong>field</strong> <strong>emissions</strong> for LCIs of<br />

agricultural production systems<br />

Data v3.0 (2012)<br />

Thomas Nemecek and Julian Schnetzer<br />

Agroscope Reckenholz-Tänikon Research Station ART<br />

Zurich, August 2011<br />

This documentation file is mainly based on chapter 4 of ecoinvent report No. 15a (Nemecek<br />

et al. 2007) where the methods of assessment of direct <strong>field</strong> <strong>emissions</strong> for life cycle<br />

inventories (LCI) of agricultural crop production (ecoinvent data version 2) are described.<br />

Further elementary flows related to <strong>natural</strong> <strong>resources</strong> are described here, as well. This text<br />

represents an updated documentation of the methods and data sources used within the<br />

frame of updating agricultural LCIs for ecoinvent data version 3.


Life cycle inventories of Swiss and European agricultural production systems - Table of Contents<br />

Table of Contents<br />

TABLE OF CONTENTS ...................................................................................................................... 2<br />

ABBREVIATIONS ............................................................................................................................... 3<br />

1 BASIC ASSUMPTIONS ............................................................................................................... 4<br />

2 DIRECT FIELD EMISSIONS ..................................................................................................... 5<br />

2.1 EMISSIONS OF AMMONIA TO THE AIR ...................................................................................... 5<br />

2.1.1 The AGRAMMON model ................................................................................................. 5<br />

2.2 NITRATE LEACHING TO GROUND WATER ............................................................................... 8<br />

2.2.1 The SALCA-NO3 model ................................................................................................... 9<br />

2.2.2 The SQCB-NO3 model .................................................................................................. 12<br />

2.3 EMISSIONS OF PHOSPHORUS TO THE WATER ......................................................................... 15<br />

2.3.1 Phosphate Leaching to Ground Water .......................................................................... 16<br />

2.3.2 Phosphate Run-Off to Surface Water ............................................................................ 17<br />

2.3.3 Phorsphorous Emissions Through Water Erosion to Surface Water ............................ 17<br />

2.4 EMISSIONS OF N 2 O TO THE AIR .............................................................................................. 17<br />

2.5 EMISSIONS OF NO X TO THE AIR .............................................................................................. 18<br />

2.6 NUTRIENT INPUTS IN AGRICULTURAL SOILS ......................................................................... 19<br />

2.7 RELEASE OF FOSSIL CO 2 AFTER UREA APPLICATIONS .......................................................... 19<br />

2.8 EMISSIONS OF HEAVY METALS TO AGRICULTURAL SOIL, SURFACE WATER AND GROUND<br />

WATER ............................................................................................................................................... 19<br />

2.9 EMISSIONS OF PESTICIDES TO AGRICULTURAL SOIL ............................................................. 21<br />

3 NATURAL RESSOURCES ........................................................................................................ 22<br />

3.1 CO 2 FROM THE ATMOSPHERE ................................................................................................ 22<br />

3.2 LAND USE .............................................................................................................................. 22<br />

APPENDIX A ...................................................................................................................................... 26<br />

LITERATURE .................................................................................................................................... 29


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Abbreviations<br />

Abbreviations<br />

CH<br />

CH 4<br />

DM<br />

FAL<br />

FAT<br />

FiBL<br />

FU<br />

IPCC<br />

kg<br />

LCI<br />

LCIA<br />

LU<br />

m 2<br />

m 3<br />

N 2 O<br />

n.a.<br />

NH 3<br />

NO x<br />

SALCA<br />

SIP<br />

Switzerland<br />

methane<br />

dry matter<br />

Swiss Federal Research Station for Agroecology and Agriculture, Zurich-Reckenholz<br />

(today part of ART)<br />

Swiss Federal Research Station for Agricultural Economics and Engineering,<br />

Tänikon (today part of ART)<br />

Research Institute of Organic Agriculture, Frick, Switzerland<br />

functional unit<br />

Intergovernmental Panel on Climate Change<br />

kilogram (measurement of weight)<br />

life cycle inventory<br />

life cycle impact assessment<br />

livestock unit<br />

square metre (measurement of area)<br />

cubic metre (measurement of volume)<br />

dinitrogen monoxide<br />

not available<br />

ammonia<br />

nitrous oxide<br />

Swiss Agricultural Life Cycle Assessment<br />

Swiss Integrated Production<br />

3


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Basic Assumptions<br />

1 Basic Assumptions<br />

The following general assumptions are valid for the Swiss plant production system datasets covered by<br />

this documentation file:<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

The <strong>field</strong> was assumed to have a slight slope of 5% (Nemecek et al. 2005, Appendix 3.1.3; value<br />

valid for the lowlands). The <strong>field</strong> slope mainly affects soil erosion and P-<strong>emissions</strong> to the water.<br />

For the European datasets the values given by local experts were used.<br />

Humus content was assumed to be 2%, clay content 20% and potential rooting depth 80 cm<br />

(Nemecek et al. 2005, Appendix 3.1.3). These factors affect the quantity of nitrate leached.<br />

The <strong>field</strong> is situated in the lowlands. The majority of arable crops are cultivated in the lowlands,<br />

and most seed production takes place there as well. Nevertheless, a large proportion of grassland is<br />

located in the hills and mountains, and although studies (Nemecek & Huguenin 2002, Nemecek et<br />

al. 2005) have shown that the differences between the lowlands and mountainous regions in terms<br />

of environmental impacts were found to be relatively small, this fact must be borne in mind.<br />

The soil was assumed to be of average erodibility.<br />

The <strong>field</strong> plot was assumed to have no artificial drainage. The majority of the <strong>field</strong>s and meadows<br />

in Switzerland are not drained 1 . For the canton of Zurich, for instance, the percentage of drained<br />

agricultural area lies between 7 and 38%, depending on the region (Schmid & Prasuhn 2000). For<br />

the other regions in Europe the same assumption was made.<br />

Fertilisation follows current recommendations (Walther et al. 2001). In order to obtain direct<br />

payments 2 , the farmer must have a balanced nutrient balance. The fertilising recommendations<br />

(Walther et al. 2001) form the basis for calculating the nutrient balance. Consequently, it is likely<br />

that farmers generally follow these recommendations. Nevertheless, it is possible to deviate from<br />

these recommendations to a certain extent: there is a tolerance of up to 10% for a positive nutrient<br />

balance. Furthermore, a farmer may apply more fertilisers than recommended to one crop, and less<br />

to another.<br />

No special measures are taken to prevent soil erosion, except the application of green manure for<br />

spring-sown crops. This is in accordance with the data source chosen for the use of machinery<br />

(LBL et al. 2000).<br />

The average density of livestock units (LU) per hectare was set at 1.3 LU/ha (BLW 2003). This<br />

value was used to calculate the potential N-mineralisation of the soil, except for the extensive<br />

meadow, where no fertiliser is applied at all. No distinction has been made between integrated and<br />

organic farming, even if fertilising practise is different. Organic farms apply more manure to<br />

arable crops than do integrated farms. If the entire crop rotation is considered, however, this<br />

difference almost disappears (FAT 2000a), since the farmyard manure is applied to a larger extent<br />

to the meadows in the integrated farm.<br />

The Swiss plant production inventories in ecoinvent refer to this “standard situation”. In conditions<br />

differing from this situation, the <strong>emissions</strong> may differ substantially from the values in ecoinvent data.<br />

1 Personal communication from V. Prasuhn, ART, September 2002.<br />

2 Verordnung über die Direktzahlungen in der Landwirtschaft (Direktzahlungsverordnung, DZV), 7.12.1998.<br />

4


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

2 <strong>Direct</strong> Field Emissions<br />

2.1 Emissions of Ammonia to the Air<br />

Ammonium (NH 4 + ) contained in fertilisers can easily be converted into ammonia (NH 3 ) and released<br />

to the air. Agriculture is the biggest source of ammonia <strong>emissions</strong> in Switzerland. For 2000, Thöni et<br />

al. (2007) estimated the total <strong>emissions</strong> of NH 3 to be 53,000 tonnes, thereof 93% from agriculture.<br />

Animal husbandry (<strong>emissions</strong> in the stable, during manure storage and spreading) is the largest source.<br />

About 30% of the excretions of N are lost in the form of ammonia. By taking appropriate measures,<br />

these <strong>emissions</strong> could be reduced by about 20-40% (Menzi et al. 1997).<br />

Ammonia contributes to acidification and the eutrophication of sensitive ecosystems. Its impact is<br />

mainly local and regional.<br />

A comparison of different emission factors for ammonia can be found in Menzi et al. (1997).<br />

2.1.1 The AGRAMMON model<br />

Geographic scope of application: global<br />

The losses of NH 3 <strong>emissions</strong> were calculated based on the model Agrammon (www.agrammon.ch), a<br />

model especially designed for the assessment of NH 3 <strong>emissions</strong> from agriculture on either farm scale<br />

or on a regional scale. The relevant modules of the model applied here are, on the farm scale,<br />

„application‟, referring to <strong>emissions</strong> from the application of farm manure, and „plant production‟,<br />

referring to <strong>emissions</strong> from the application of mineral and recycling fertilisers. The model structure<br />

and technical parameters can be found in Agrammon Group (2009a, b).<br />

Parameters required by the model that were not available from the production inventories were<br />

complemented with standard values proposed in the user interface implemented online, e.g. the<br />

fractions of slurry application techniques in practice (cf. Tab. 2.1 & Tab. 2.2). These standard values<br />

shall reflect a representative distribution of alternatives in agricultural practices and do not necessarily<br />

correspond to the „basic system‟ in Agrammon and, thus, the resulting correction factors deviate from<br />

1 (cf. following paragraph). The standard values are based on a survey described in Kupper et al.<br />

(2010) and a corresponding summary of the model parameters deducted from this survey (SHL 2010).<br />

‘Application’ of farmyard manure<br />

The module „application‟ is subdivided into three categories which are application of liquid manure, of<br />

solid manure and of poultry manure. The formulae for all sub-modules follow the same principle:<br />

NH 3 –N = TAN * (er + c_app) * c x<br />

NH 3 –N = nitrogen <strong>emissions</strong> in form of NH 3 (kg N/ha)<br />

TAN = Total ammonium nitrogen; this is considered equal to the soluble nitrogen content<br />

(Agrammon Group 2009b) and is calculated as the product of amount of farmyard manure<br />

(kg/ha) and the corresponding soluble nitrogen content (kg N/kg manure) according to Flisch et<br />

al. (2009) (kg N/ha) (Tab. 2.3)<br />

er = emission rate; this is a constant emission rate for each type of farm manure (%/100 of<br />

TAN) (Tab. 2.4)<br />

c_app = correction factor that influences the emission rate; it refers to the amount of manure<br />

per application and its degree of dilution; applies only for liquid manure (dimensionless).<br />

c x = correction factor x; this refers to various parameters of the crop production system; for the<br />

basic system assumed in Agrammon c x = 1; c x < 1 has a reducing effect on NH 3 –<strong>emissions</strong>, c x ><br />

1 an increasing effect (dimensionsless, see Tab. 2.1 for the explanation of the variables).<br />

5


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

c x = c_tech * c_soft * c_season for liquid manure<br />

c x = c_incorp_time * c_season for solid and poultry manure<br />

The calculation of correction factors is described in Agrammon Group (2009a). The correction factors<br />

of liquid manure are characterised in Tab. 2.1; for solid and poultry manure the same correction<br />

factors apply (Tab. 2.2). In the case of solid and poultry manure, the date of base dressing was used to<br />

determine c_season.<br />

Tab. 2.1 Correction factors (c x) for application of liquid manure<br />

c x Description Calculation Applied<br />

c_app<br />

c_tech<br />

c_soft<br />

c_season<br />

represents the amount of manure per application (applied<br />

standard value: 30 m 3 /ha) and its degree of dilution (40%<br />

liquid manure : 60% water)<br />

represents the technical equipment applied for slurry<br />

spreading<br />

equipment:<br />

splash plate 90<br />

trailing hose 10<br />

% of application:<br />

represents the proportions of manure applied on hot days<br />

and in evening hours<br />

application in evening hours 20%<br />

application on hot days<br />

sometimes<br />

represents the proportions of manure applied in summer<br />

(June-August) and the rest of the year<br />

based on crop<br />

data<br />

based on<br />

standard<br />

values<br />

based on<br />

standard<br />

values<br />

based on crop<br />

data<br />

value<br />

-0.029<br />

0.97<br />

0.96<br />

variable<br />

Tab. 2.2<br />

Correction factors (c x) for the application of solid and poultry manure<br />

c x Description Calculation Applied<br />

value<br />

c_incorp_time<br />

c_season<br />

represents the time span between manure<br />

application and incorporation<br />

incorporation of manure:<br />

within 1 day 20<br />

within 3 days 20<br />

after more than 3 days 10<br />

no incorporation 50<br />

% of application:<br />

represents the proportions of manure applied in<br />

summer (June-August) and the rest of the year<br />

based on<br />

standard values<br />

based on crop<br />

data<br />

cattle/pig:<br />

0.88;<br />

poultry:<br />

0.82<br />

variable<br />

Tab. 2.3<br />

Nitrogen contents of different types of manure. N total = total nitrogen content; N soluble = soluble nitrogen<br />

content (Flisch et al. 2009), this is considered to be equal to TAN. The values for liquid manure apply to<br />

liquid manure without addition of water.<br />

Animal category Manure type Unit kg N soluble/unit<br />

Cattle liquid manure kg/m 3 2.3<br />

low-excrement liquid manure kg/m 3 3.2<br />

staple manure kg/t 0.8<br />

solid manure from loose housing kg/t 1.3<br />

6


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

Pigs liquid manure kg/m 3 4.2<br />

solid manure kg/t 2.3<br />

Poultry broiler manure kg/t 10.0<br />

laying hen manure kg/t 6.3<br />

laying hen litter kg/t 7.0<br />

dried poultry litter kg/t 9.0<br />

Tab. 2.4<br />

Nitrogen emission rates (er) of different animal categories and manure types<br />

Animal category manure type er (% TAN)<br />

Cattle Liquid 50<br />

Solid 80<br />

Pigs Liquid 35<br />

Solid 80<br />

Poultry Solid, from growers, layers and other poultry 30<br />

Solid, from broilers and turkeys 65<br />

‘Plant production’<br />

The module „plant production‟ is subdivided into the sub-modules „agricultural area‟, „mineral<br />

fertiliser‟ and „recycling fertiliser‟. The sub-module „agricultural area‟ defines a standard emission of<br />

2 kg NH 3 -N/ha from the leaf surface of plants. As a similar level of emission could be expected from<br />

any other vegetated area and is not due to agricultural practice, this sub-module was left out of<br />

consideration. The sub-module for recycling fertilisers – like compost and liquid or solid digestate –<br />

is, so far, only applied to sugarcane production in Brazil, where vinasse, a by-product of sugar<br />

production and considered a „liquid digestate‟, is applied to <strong>field</strong>s for nitrogen fertilisation (Tab. 2.5).<br />

The NH 3 <strong>emissions</strong> from applied mineral fertilisers are calculated by constant emission factors for<br />

each group of fertiliser. Instead of the emission factors suggested in Agrammon group (2009a) (15%<br />

for urea and 2% for all other mineral fertiliser) a set of emission factors was applied that distinguishes<br />

a greater number of different fertiliser groups (Asman 1992; Tab. 2.6).<br />

Tab. 2.5<br />

Parameters used in calculation of NH3-N <strong>emissions</strong> due to vinasse application on sugarcane <strong>field</strong>s in Brazil.<br />

Parameter Value Source<br />

Total N content of vinasse [g/l] 0.27 Jungbluth et al. 2007<br />

Fraction of TAN of total N in vinasse [%/100] 0.5 Flisch et al. 2009<br />

Emission factor of TAN from liquid digestate [%/100] 0.6 Agrammon Gruop 2009b<br />

7


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

Tab. 2.6 NH 3-<strong>emissions</strong> from mineral fertilisers (% N emitted in form of NH 3).<br />

Type of fertiliser Emission factor for NH 3-N<br />

ammonium nitrate, calcium ammonium nitrate 2 %<br />

ammonium sulphate 8 %<br />

urea 15 %<br />

multinutrient fertilisers (NPK-, NP-, NK-fertilisers) 4 %<br />

urea ammonium nitrate 5.7 % *)<br />

ammonia, liquid 3 %<br />

*) The weighted average of ammonium nitrate (2/3 of N) and urea (1/3 of N) was taken, since no emission factor is<br />

given by Asman (1992).<br />

2.2 Nitrate Leaching to Ground Water<br />

Nitrate (NO 3<br />

- ) is either supplied to the soil by fertilisers or produced by micro-organisms in the soil<br />

via the mineralisation of organic matter. Nitrate in the soil can be absorbed as a nutrient by the plants.<br />

In periods of heavy rainfall, however, precipitation exceeds soil evaporation and transpiration of the<br />

plants, which leads initially to saturation of the soil with water, and afterwards to percolation to the<br />

ground water. As nitrate is easily dissolved in water, the risk of leaching is high. This situation is quite<br />

frequent in Switzerland.<br />

The risk of nitrate leaching is highest in autumn and winter, when precipitation often or always<br />

exceeds uptake by the plants. Moreover, nitrogen mineralisation is generally highest in late summer,<br />

when the nitrogen often cannot be taken up by the plants (Stauffer et al. 2001).<br />

Experiments have shown that it is not the choice of crops but rather the succession of crops in a crop<br />

rotation that is determining the amount of nitrate leached (Stauffer et al. 2001). Since the modules in<br />

the ecoinvent database are life cycle inventories of products taking into account one single crop only,<br />

the succession of crops can only partly be taken into account. This fact should be borne in mind when<br />

interpreting the nitrate leaching values.<br />

Nitrate losses are undesirable for several reasons:<br />

<br />

<br />

<br />

From the agricultural point of view, valuable nutrients are lost from the soil, increasing the need<br />

for fertilisers.<br />

Nitrate in ground water used as drinking water may have a toxic impact to humans. Although the<br />

acute toxicity of nitrate is low, nitrate is easily converted into nitrite, which has a higher acute<br />

toxicity and is supposed to be indirectly carcinogenic (Surbeck & Leu 1998).<br />

Once ground water becomes surface water, nitrate contributes to eutrophication and also induces<br />

<strong>emissions</strong> of nitrous oxide, a major greenhouse gas (Schmid et al. 2000).<br />

The tolerance level for nitrate in drinking water is 40 mg/l in Switzerland and 50 mg/l in the EU, while<br />

the Swiss quality goal is 25 mg/l maximum. Results from the Swiss monitoring network NAQUA<br />

(Greber et al. 2002) show that these levels are exceeded only in areas with arable crops, or in fruitand<br />

wine-growing areas. In areas with forests or permanent grassland, these levels have never been<br />

exceeded. This shows the importance of arable crops and soil cultivation in nitrate leaching.<br />

Nitrate <strong>emissions</strong> to ground water can be estimated by simulation models, although this method is very<br />

complex and time-consuming and does not always lead to very satisfactory results (Oberholzer et al.<br />

2001). A comparison of different methods for estimating nitrate leaching is given in Audsley et al.<br />

(1997).<br />

Depending on the country of crop production different models were used to calculate nitrate leaching.<br />

A model by Richner et al. (in prep.) specifically for the application to conditions in Switzerland<br />

(SALCA-NO3) was applied to Switzerland and other European countries, where similar conditions are<br />

found. For non-European countries the SQCB-NO3 model was used, a geographically unspecific and<br />

8


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

simpler model (de Willigen 2000, in: Faist Emmenegger et al. 2009). Both models are described<br />

below.<br />

2.2.1 The SALCA-NO3 model<br />

Geographic scope of application: Europe<br />

The model SALCA-NO3 calculates the expected nitrate leaching and comprises the following<br />

elements (Richner et al. in prep.):<br />

<br />

<br />

<br />

<br />

<br />

Nitrogen mineralisation from the soil organic matter per month<br />

Nitrogen uptake by vegetation (if any) per month<br />

Nitrogen input from the spreading of fertiliser<br />

Soil depth<br />

Factors not considered:<br />

o<br />

o<br />

Amount of seepage<br />

Denitrification<br />

The following description is an extract of the full description of the model SALCA-nitrate by Richner<br />

et al. (in prep.). The reader is referred to this report for further information.<br />

The model of Richner et al. (in prep.) calculates the expected nitrate leaching of arable crops,<br />

meadows and pasture land considering not only crop rotation, soil cultivation, nitrate fertilising but<br />

also nitrate mineralisation from the soil organic matter, nitrate uptake by the plants and various soil<br />

conditions. The model is valid for the Swiss lowland and adjoining regions. The calculation bases on<br />

the monthly difference between the amount of mineralized nitrate in the soil and the nitrate uptake of<br />

the plants. Furthermore, the nitrate leaching risk from fertiliser application during inappropriate time<br />

periods is taken into account. The expected nitrate leaching of pastures rises because of locally high<br />

nitrate concentrations. Therefore the total amount of nitrate on pastures is calculated from the number<br />

of animals, the grazing duration and the grazing period.<br />

The total expected nitrate leaching of an arable crop is assessed by the sum of the monthly values<br />

within the assessment period starting one month after the harvest of the former crop and ending in the<br />

month of harvesting of the given crop.<br />

The model distinguishes three different regions – valley, hill and mountain – each of which defines a<br />

specific climate regime. Virtually all Swiss plant production inventories in ecoinvent refer to<br />

production in the valley region, hence the model parameters shown below refer to that selfsame<br />

region.<br />

Tab. 2.7 shows the expected nitrogen mineralisation for default settings of clay and humus content in<br />

the valley region. The monthly mineralisation may be increased by certain intensive soil cultivation<br />

operations aerating the soil and thereby promoting microbial activity.<br />

Tab. 2.7<br />

Expected nitrogen mineralisation (N min m, kg N per ha and month, from Richer et al. in prep.) in soils with<br />

15% clay, 2% humus and N input from farm manure of 1 LU/ha in the valley region. Intensive soil cultivation<br />

means treatment by a rotary cultivator or a rotary harrow in the respective month. In months where there is<br />

no intensive soil cultivation, the values “Without intensive soil cultivation” are used.<br />

Jan. Feb. March Apr. May June July Aug. Sept. Oct. Nov. Dec.<br />

Without intensive soil cultivation 0 0 6 9 12 15 17 21 23 12 6 0<br />

With intensive soil cultivation 0 0 10 15 20 25 29 38 38 20 10 0<br />

9


Clay<br />

content(%)<br />

<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

Nitrogen mineralisation was further corrected for clay and humus content of the soil (Tab. 2.8) as well<br />

as for green manuring and tillage of pastures (see Richner et al. in prep.).<br />

Tab. 2.8<br />

Correction factors of nitrate mineralization (%) against the clay and humus content of the soil.<br />

Humus content (%)<br />

40 - 30 % - 30 % - 25% - 15 %<br />

Nitrogen uptake by vegetation was estimated based on the model STICS (Brisson et al. 2003) with a<br />

high temporal resolution (100 time steps from sowing to physiological maturity of the crop in<br />

question). These nitrogen uptake functions were determined for the crops grass, protein peas, barley,<br />

potatoes, maize, rapeseed, soy beans, sunflower, wheat and sugar beets assuming for each crop a<br />

standard yield and a corresponding standard nitrogen uptake as given in Flisch et al. (2009). Nitrogen<br />

uptake of other crops was approximated by these functions or by combinations of them (for details<br />

refer to the appendix of Richner et al. in prep.). Variations in nitrogen uptake due to yields deviating<br />

from the standard yield were accounted for by scaling the nitrogen uptake relative to the difference<br />

between standard and real yields.<br />

Nitrogen input from farm manure is considered in terms of livestock units per hectare (LU/ha). Based<br />

on the average number of livestock units of farms in the Swiss lowlands (BLW 2003), this parameter<br />

(St) was set to 1.3 LU/ha for all calculations (average of the years 2000 to 2002), except for the<br />

extensive meadow, where St=0, since no fertiliser is applied (see chapter 1), and for other meadow<br />

types, where St varies in the range of 1.3-1.5. The basic values of nitrogen mineralisation which refer<br />

to 1 LU/ha linearly decrease or increase with St by 10% per 1 LU/ha. For the European datasets, a<br />

farm without livestock was assumed (St=0).<br />

The risk of nitrogen leaching due to fertiliser application is dependent on the crop and the month in<br />

which fertiliser was applied (Tab. 2.9.; Richner et al. in prep.).<br />

Tab. 2.9 Risk of nitrogen leaching (fraction of potentially leachable nitrogen of the N applied through fertilisers in %,<br />

from Richner et al. in prep.).<br />

Months Winter cereals Maize,<br />

soya<br />

beans<br />

sowing<br />

year<br />

harvestyear<br />

harvestyear<br />

Winter rape seed<br />

and green manure<br />

sowing<br />

year<br />

harvestyear<br />

Potato,<br />

sugar and<br />

fodder<br />

beets<br />

harvestyear<br />

Faba<br />

beans,<br />

protein<br />

peas<br />

(spring<br />

sown)<br />

harvestyear<br />

harvestyear<br />

Sunflowers<br />

Permanent<br />

meadow<br />

Int<br />

Permanent<br />

meadow<br />

Ext<br />

January 100 50 100 100 20 100 100 100 20 20<br />

February 100 30 100 100 10 100 100 100 10 20<br />

March 100 10 100 100 0 50 50 50 0 0<br />

April 100 0 80 100 0 30 30 30 0 0<br />

May 100 0 70 100 0 10 0 0 0 0<br />

June 100 0 0 100 0 0 0 0 0 0<br />

July 100 - 0 100 - 0 0 0 0 0<br />

August 100 - 0 80 - 0 - 0 0 0<br />

10


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

Months Winter cereals Maize,<br />

soya<br />

beans<br />

Winter rape seed<br />

and green manure<br />

Potato,<br />

sugar and<br />

fodder<br />

beets<br />

Faba<br />

beans,<br />

protein<br />

peas<br />

(spring<br />

sown)<br />

Sunflowers<br />

Permanent<br />

meadow<br />

Int<br />

September 90 - 0 0 - 0 - - 0 0<br />

October 90 - - 0 - - - - 0 0<br />

Permanent<br />

meadow<br />

Ext<br />

November 90 - - 20 - - - - 10 20<br />

December 90 - - 20 - - - - 20 20<br />

The correction of the expected nitrate leaching due to fertiliser application against the depth of the soil<br />

is listed in Tab. 2.10.<br />

Tab. 2.10<br />

The correction of the expected nitrate leaching due to fertiliser application against the depth of the soil<br />

(Richner et al. in prep.)<br />

Soil depth (cm) Correction (%)<br />

> 100 0<br />

91-100 +5<br />

81-90 +10<br />

71-80 +15<br />

61-70 +20<br />

51-60 +25<br />

41-50 +30<br />

≤ 40 +35<br />

There is no leaching water during the intensive vegetation period because the evapotranspiration is<br />

similar or higher than the precipitation. Therefore usually no nitrate leaching occurs during this period.<br />

For various crops fertilising is only possible shortly before the growing period due to agronomic or<br />

technical reasons. The model accumulates the monthly values of nitrate mineralisation, nitrate uptake<br />

by the plants and the nitrate from fertilising during this period (Tab. 2.11).<br />

Tab. 2.11<br />

Accumulation of the monthly values of nitrate mineralisation, nitrate uptake by the plants and the nitrate<br />

from fertilising for various crops (Richner et al. in prep.).<br />

Month<br />

Crop J F M A M J J A S O N D<br />

winter cereal<br />

spring cereal<br />

maize, soybean<br />

potato<br />

sugar beet, fodder beet<br />

sunflower<br />

fava bean, protein pea (spring sown)<br />

fava bean, protein pea (autumn sown)<br />

permanent meadow<br />

As nitrate leaching is strongly dependent on the availability of water percolating the top soil which, in<br />

turn, is dependent on precipitation, a correction factor is introduced, in addition to the model SALCA-<br />

NO3, for regions other than the Swiss lowlands to which the model is adapted. This „nitrate leaching<br />

11


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

transformation factor‟ represents the ratio of winter precipitations (Octobre to March) of the region in<br />

question and of Reckenholz (Switzerland, site of model calibration) as most leaching occurs in this<br />

period. The results of SALCA-NO3 are multiplied by the respective transformation factor. For Swiss<br />

production systems this factor is constantly set to 1. For all other regions, the considered winter<br />

precipitations and transformation factors are presented in Tab. 2.12.<br />

Tab. 2.12<br />

Winter precipitations and nitrate leaching transformation factors for the different regions<br />

Winter precipitations<br />

(October-March) in mm<br />

Nitrate leaching<br />

transformation factor<br />

Swiss lowlands (site Reckenholz) 433 1<br />

Barrois 381 0.88<br />

Castilla-y-Leon 266 0.61<br />

Saxony-Anhalt 183 0.42<br />

Europe *) 219 0.51<br />

*) In this case, rye is the only affected crop which is mainly produced in Eastern Europe. Winter precipitation was<br />

calculated as the average of all available weather stations in the Polish middle and low lands<br />

(www.klimadiagramme.de).<br />

2.2.2 The SQCB-NO3 model<br />

The SQCB-NO3 model is reported in Faist Emmenegger et al. (2009) and is an adaption of a formula<br />

developed by de Willigen (2000). The formula calculates the leaching of NO3-N and is a simple<br />

regression model of the form:<br />

P<br />

N 21.37<br />

0.0037*<br />

S 0.0000601* Norg 0.00362*<br />

U<br />

c*<br />

L<br />

where:<br />

N = leached NO3-N [kg N/(ha*year)]<br />

P = precipitation + irrigation [mm/year]<br />

c = clay content [%]<br />

L = rooting depth [m]<br />

S = nitrogen supply through fertilisers [kg N/ha]<br />

N org = nitrogen in organic matter [kg N/ha]<br />

U = nitrogen uptake by crop [kg N/ha]<br />

It must be mentioned that in Faist Emmenegger et al. (2009) the formula has been taken from Roy et<br />

al. (2003), where it is not reported correctly (p. 51, formula “OUT3”), stating C org instead of N org<br />

(details for calculation of N org from C org see below).<br />

The SQCB model provides relatively simple approaches to assess most of the required input<br />

parameters. P and C org are determined through the ecozone in which the crop is produced. The<br />

ecozones for the whole globe are defined and presented as maps in FAO (2001). Fix values for carbon<br />

content in the upper 30 cm of soil and for annual precipitation are assigned to each ecozone (see Tab.<br />

2.13). The carbon content in tonnes per 3000 m 3 (1 ha [area] * 30 cm [depth]) is converted into mass<br />

fraction by the formula:<br />

C org [%] = C org [t/3000 m 3 ] * (1 / 1.3 t m -3 ) * 100.<br />

In case of irrigation, the amount of irrigation water [mm] is added to the precipitation in order to<br />

obtain the parameter P. Precipitation values for montane ecozones were calculated as an average –<br />

<br />

12


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

weighted if sufficiently detailed data were available – of the annual precipitations of all representative<br />

weather stations available at www.klimadiagramme.de.<br />

Where several ecozones were covered by the crop producing region of the respective transforming<br />

activity, the model was applied to each ecozone and an average nitrate leaching rate for the whole<br />

producing region was calculated from the ecozone-wide results, weighted by the contribution of each<br />

ecozone to crop production – in terms of harvested acreage or production volume according to data<br />

availability. The same applied for several USDA soil orders within one producing region or ecozone<br />

(see below).<br />

The information for weighting the contribution of sub-units (by ecozone or USDA soil order) were<br />

gained from comparisons of the ecozone or soil map, respectively, with a map of the spatial<br />

distribution of crop production in the respective country or with equivalent spatial information. This<br />

information was taken from USDA (2009) for maize, wheat, potatoes, soybeans, rice, rape seed and<br />

cotton in the USA, from USDA (2004a) for soybeans and Goldemberg (2008) for sugarcane in Brazil,<br />

and from Hsu & Gale (2001) for cotton and Zhao (2008) for sweet sorghum in China.<br />

Tab. 2.13<br />

FAO ecozones and their assigned carbon content and annual precipitation. Due to high variability in<br />

precipitation, no values are given for montane ecozones. For these ecozones precepetation values have to<br />

be researched in each individual case. (From Faist Emmenegger et al. 2009)<br />

FAO ecozones<br />

Carbon content<br />

[t/ha in upper 30cm<br />

= t/3000 m 3 ]<br />

Annual precipitation<br />

[mm]<br />

Tropical wet 59 2500<br />

Tropical moist 48 1500<br />

Tropical dry 34 1000<br />

Tropical dry 34 500<br />

Tropical dry 34 50<br />

Tropical montane 55 -<br />

Warm temperate moist 55 1200<br />

Warm temperate dry 25 700<br />

Warm temperate dry 25 400<br />

Warm pemperate dry 25 200<br />

Warm temperate moist or dry 40 -<br />

Cool temperate moist 81 1500<br />

Cool temperate moist 81 600<br />

Cool temperate dry 38 300<br />

Cool temperate dry 38 150<br />

Cool temperate moist or dry 59 -<br />

Boreal moist 22 500<br />

Boreal dry 22 400<br />

Boreal moist and dry 22 -<br />

They clay content c is defined by the USDA soil order of a producing region or its sub-unit,<br />

respectively. A constant value for clay content is assigned to each USDA soil order based on USDA<br />

(1999) (see Tab. 2.14). The maps for defining sub-units of production regions or ecozones by soil<br />

orders were taken from USDA (1999), as well, and more detailed maps especially for the USA from<br />

the USDA website (http://soils.usda.gov/technical/classification/orders/).<br />

Tab. 2.14 USDA soil orders and their assigned clay contents. (From Faist Emmenegger et al. 2009)<br />

USDA soil order clay content [%]<br />

Alfisol 28.0<br />

Andisol 10.4<br />

13


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

USDA soil order clay content [%]<br />

Aridisol 17.2<br />

Entisol 3.5<br />

Gelisol 23.7<br />

Histosol 2.0<br />

Inceptisol 4.9<br />

Mollisol 21.1<br />

Oxisol 53.9<br />

Spodosol 1.8<br />

Ultisol 12.3<br />

Vertisol 49.0<br />

The rooting depth for several crops is given in the SQCB report by Faist Emmenegger (2009). The<br />

missing values were taken from other literature. Values and sources are presented in Tab. 2.15. Where<br />

information was available, values from the SQCB report were replaced by values from FAO (2011).<br />

Tab. 2.15<br />

Crops and their rooting depth as assumed for calculations.<br />

Crop Rooting depth [m] Source<br />

Potatoes 0.5 FAO 2011<br />

Sugar cane 1.6 FAO 2011<br />

Sweet sorghum 1.5 FAO 2011<br />

Rape seed 0.9 SQCB report<br />

Soybeans 0.95 FAO 2011<br />

Oil palm 1.0 SQCB report<br />

Wheat 1.2 FAO 2011<br />

Maize 1.35 FAO 2011<br />

Rice 0.6 Mishra et al. 1997<br />

Cotton 1.35 FAO 2011<br />

The nitrogen supply S was taken from the unit process itself and, if necessary, converted to nitrogen<br />

supply per hectare by multiplication with the the yield given in the respective unit process‟ general<br />

comment <strong>field</strong>.<br />

The nitrogen uptake U is given for several crops in Faist Emmenegger et al. (2009). For the remaining<br />

crops nitrogen uptake was taken from literature. Tab. 2.16 presents the nitrogen uptake per hectare;<br />

original values are given in kilogrammes per tonne of product in the SQCB report and are converted to<br />

tonnes per hectare here. For the other crops literature values were treated in the same way and values<br />

were adjusted by the ratio of yields in literature and in the unit process of the transforming activity, if<br />

necessary. In the case of soybeans, only 40% of the values given in the SQCB report are considered as<br />

nitrogen uptake in order to reflect the fact, that the remaining 60% are fixed from the air and are not<br />

directly relevant to the balance of nitrogen supplied through fertilisers and mineralised from the soil<br />

organic matter (Schmid et al. 2000).<br />

Tab. 2.16<br />

Crops and their nitrogen uptake as assumed for calculations. Note that one crop can have several different<br />

values according to different yields and/or different literature sources for the respective countries.<br />

Crop<br />

Producing Nitrogen uptake Source<br />

country [kg N/ha]<br />

Potatoes USA 154 SQCB report<br />

Sugar cane Brazil 152 SQCB report<br />

Sweet sorghum China 193 SQCB report<br />

Rape seed USA 53 SQCB report<br />

14


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

Crop<br />

Producing Nitrogen uptake Source<br />

country [kg N/ha]<br />

Soybeans USA 81 SQCB report<br />

Soybeans Brazil 78 SQCB report<br />

Oil palm Malaysia 150 SQCB report<br />

Wheat USA 51 Flisch et al. 2009<br />

Maize USA 196 Flisch et al. 2009<br />

Rice USA 119 Swain et al. 2006<br />

Cotton USA 89 Boquet & Breitenbeck 2000<br />

Cotton China 135 Dong et al. 2010<br />

To calculate the organic nitrogen N org in soil [kg N/ha] from the soil organic carbon content C org [%]<br />

the following quantities are needed:<br />

<br />

soil volume V [m 3 /ha]<br />

V is taken to be 5000 m 3 , which means that the upper 50 cm of soil are considered<br />

(according to pers. comm. J. Leifeld, ART, 2011), assuming the same carbon content for<br />

30-50 cm depth as calculated above for 0-30 cm depth.<br />

bulk density D b [kg/m 3 ]<br />

<br />

<br />

Bulk density is taken to be 1300 kg/m 3 , which is the standard value from the SQCB report.<br />

C/N ratio r C/N [dimensionless]<br />

The C/N ratio is taken to be 11. This is the mean value of the range (10-12) determined<br />

through literature research (Batjes 2008; Scheffer 2002; Eggleston et al. 2006) and<br />

consultation of experts (pers. comm. J. Leifedl, ART).<br />

ratio of N org to N tot (total soil nitrogen) r Norg [dimensionless]<br />

The C/N ratio expresses the ratio of C org and N tot . The ratio r Norg is needed calculate N org<br />

from N tot , which is calculated in a first step applying the C/N ratio. r Norg is assumed to be<br />

0.85 (Scheffer 2002).<br />

N org is calculated by the formula:<br />

N org is the mass of organic nitrogen contained in the upper 50 cm of soil. Naturally only a fraction of<br />

this mass is mineralised and, hence, available for uptake by plants and leaching to the ground water.<br />

This fraction is determined by the mineralisation rate, which is 1.6% here and implicitly included in<br />

the regression coefficient of the term N org .<br />

2.3 Emissions of Phosphorus to the Water<br />

Phosphorus (P) is an important plant nutrient and must be supplied to the plants in sufficient<br />

quantities. A part of the phosphorus is lost to water due to leaching, run-off and soil erosion through<br />

water. As phosphorus is a limiting nutritional element in <strong>natural</strong> water bodies, P <strong>emissions</strong> can cause<br />

eutrophication (Prasuhn & Grünig 2001). Soil erosion by wind is not considered here.<br />

We distinguish between three different kinds of phosphorus <strong>emissions</strong> to water:<br />

<br />

leaching of soluble phosphate (PO 4 ) to ground water (inventoried as “phosphate, to ground<br />

water”),<br />

15


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

<br />

<br />

run-off of soluble phosphate to surface water (inventoried as “phosphate, to surface water”),<br />

erosion of soil particles containing phosphorus (inventoried as “phosphorus, to surface water”).<br />

The emission models SALCA-P (Prasuhn 2006) developed by ART are applied in ecoinvent data. A<br />

comparison of different emission coefficients is given by Audsley et al. (1997), Schmid & Prasuhn<br />

(2000) and Prasuhn & Grünig (2001).<br />

The following factors are considered for the calculation of P <strong>emissions</strong> in ecoinvent data inventories:<br />

<br />

<br />

<br />

<br />

type of land use<br />

type of fertiliser<br />

quantity of P in fertilisers<br />

type and duration of soil cover for the calculation of the soil erosion (C-factor).<br />

For other factors, considered in the model SALCA-P, default values are used:<br />

<br />

<br />

<br />

<br />

distance to next river or lake<br />

topography<br />

chemical and physical soil properties<br />

drainage. As the <strong>field</strong> was assumed to have no drainage (see chapter 1), the <strong>emissions</strong> to surface<br />

water through drainage were not taken into account.<br />

The model takes soil erosion, surface run off and drainage losses to surface water and leaching to<br />

ground water into account.<br />

It should be borne in mind that the values are valid for the soil and site parameters chosen. Changes in<br />

soil conditions or in cropping practice could lead to <strong>emissions</strong> substantially different from the ones<br />

calculated in ecoinvent data.<br />

The key factors of the model are listed below. Please see Prasuhn (2006) for detailed calculations.<br />

2.3.1 Phosphate Leaching to Ground Water<br />

P leaching to the ground water was estimated as an average leaching, corrected by P-fertilisation:<br />

P gw = P gwl * F gw<br />

P gw = quantity of P leached to ground water (kg/(ha*a))<br />

P gwl = average quantity of P leached to ground water for a land use category (kg/(ha*a)), which<br />

is 0.07 kg P/(ha*a) for arable land and<br />

0.06 kg P/(ha*a) for permanent pastures and meadows.<br />

F gw = correction factor for fertilisation by slurry (-)<br />

F gw = 1 + 0.2/80*P 2 O 5sl<br />

P 2 O 5sl = quantity of P 2 O 5 contained in the slurry or liquid sewage sludge (kg/ha). The values of<br />

P 2 O 5 -content were taken from Walther et al. (2001).<br />

16


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

2.3.2 Phosphate Run-Off to Surface Water<br />

Run-off to surface water was calculated in a similar way to leaching to ground water:<br />

P ro = P rol * F ro<br />

P ro = quantity of P lost through run-off to rivers (kg/(ha*a))<br />

P rol = average quantity of P lost through run-off for a land use category (kg/(ha*a)), which is<br />

0.175 kg P/(ha*a) for open arable land,<br />

0.25 kg P/(ha*a) for intensive permanent pastures and meadows and<br />

0.15 kg P/(ha*a) for extensive permanent pastures and meadows<br />

F ro = correction factor for fertilisation with P (-), calculated as:<br />

F ro = 1 + 0.2/80 * P 2 O 5min + 0.7/80 * P 2 O 5sl + 0.4/80 * P 2 O 5man<br />

P 2 O 5min = quantity of P 2 O 5 contained in mineral fertilisers (kg/ha)<br />

P 2 O 5sl = quantity of P 2 O 5 contained in slurry or liquid sewage sludge (kg/ha)<br />

P 2 O 5man = quantity of P 2 O 5 contained in solid manure (kg/ha)<br />

The values of P 2 O 5 -content for slurry and manure were taken from Walther et al. (2001).<br />

2.3.3 Phorsphorous Emissions Through Water Erosion to Surface Water<br />

P <strong>emissions</strong> through erosion of particulate phosphorous to surface water were calculated as follows:<br />

P er = S er * P cs * F r * F erw<br />

P er = quantity of P emitted through erosion to rivers (kg P/(ha*a))<br />

S er = quantity of soil eroded (kg/(ha*a))<br />

P cs = P content in the top soil (kg P/kg soil). The average value of 0.00095 kg/kg was used.<br />

F r = enrichment factor for P (-). The average value of 1.86 was used (Wilke & Schaub 1996).<br />

This factor takes account of the fact that the eroded soil particles contain more P than the<br />

average soil.<br />

F erw = fraction of the eroded soil that reaches the river (-). The average value of 0.2 was used.<br />

The amount of eroded soil S er is calculated according to Oberholzer et al. (2006, Appendix A4.1).<br />

2.4 Emissions of N 2 O to the Air<br />

Nitrous oxide or dinitrogen monoxide (N 2 O) is produced as an intermediate product in the<br />

denitrification process (conversion of NO 3<br />

- into N 2 ) by soil micro-organisms. It can also be produced<br />

as a by-product in the nitrification process (conversion of NH 4 + into NO 3<br />

- , Schmid et al. 2000). The<br />

total <strong>emissions</strong> of N 2 O caused by the Swiss agricultural sector in 1996 were estimated at 8,600 tonnes.<br />

N losses in the form of N 2 O are closely linked to the nitrogen cycle in agriculture; intensive agriculture<br />

with a high input of nitrogen fertiliser contributes to the increase in N 2 O-<strong>emissions</strong>. N 2 O is a<br />

greenhouse gas with a high impact.<br />

Calculations of N 2 O <strong>emissions</strong> are based on the IPCC method for calculating N 2 O <strong>emissions</strong><br />

(Eggleston et al. 2006). <strong>Direct</strong> <strong>emissions</strong> of N 2 O and indirect or induced <strong>emissions</strong> are included. In the<br />

case of indirect N 2 O emission, nitrogen is first emitted as NH 3 or NO 3<br />

- and subsequently converted to<br />

N 2 O.<br />

<strong>Direct</strong> N 2 O <strong>emissions</strong> [kg N 2 O] from mineral and organic fertilisers and from crop residues were<br />

calculated on the basis of the total nitrogen content (N tot [kg N]). The factor of 1.0% N lost as N 2 O was<br />

used. Induced N 2 O <strong>emissions</strong> [kg N 2 O] from ammonia (NH 3 ) were considered using a factor of 1.0%<br />

17


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

of N in emitted NH 3 , induced <strong>emissions</strong> from nitrate (NO 3<br />

- ) with a factor of 0.75% of N in leached<br />

NO 3<br />

- . According to the new IPCC-guidelines, no <strong>emissions</strong> are calculated from biological nitrogen<br />

fixation.<br />

The content of total nitrogen in farmyard manure was taken from Walther et al. (2001).<br />

The contents of total nitrogen in crop residues are taken from Walther et al. (2001) and the amounts of<br />

crop residues from Nemecek et al. (2007) as such, or scaled by the yields of the reference products<br />

(and by-products) based on the latter. For exceptions see Tab. 2.17.<br />

N 2 O = 44/28 * (0.01 (N tot + N cr ) + 0.01 * 14/17 * NH 3 + 0.0075 * 14/62 * NO 3<br />

- )<br />

N 2 O = emission of N 2 O (kg N 2 O/ha)<br />

N tot<br />

N cr<br />

NH 3<br />

NO 3<br />

-<br />

= total nitrogen in mineral and organic fertilisers (kg N/ha)<br />

= nitrogen contained in the crop residues (kg N/ha)<br />

= losses of nitrogen in the form of ammonia (kg NH 3 /ha)<br />

= losses of nitrogen in the form of nitrate (kg NO 3<br />

- /ha).<br />

Tab. 2.17 Literature sources of amounts and nitrogen contents of crop residues (other than Walther et al. 2001)<br />

Crop Amount of crop residue Nitrogen content of crop residue<br />

Rice Nemecek et al. (2007) Swain et al. (2006)<br />

Cotton Boquet & Breitenbeck (2000) Boquet & Breitenbeck (2000)<br />

Sweet sorghum Khaledian et al. (2010) Keskin et al. (2009)<br />

Oil palm Khalid et al. (1999)<br />

(577 kg N/ha in standing biomass considered as N in crop residues,<br />

allocated over 25 years of plantation lifetime)<br />

Sugar cane<br />

No crop residues due to burning of <strong>field</strong>s before harvest.<br />

2.5 Emissions of NO x to the Air<br />

During denitrification processes in soils, nitrous oxide (NO x ) may also be produced. These <strong>emissions</strong><br />

were estimated from the <strong>emissions</strong> of N 2 O 3 :<br />

NO x<br />

= 0.21 * N 2 O<br />

Since this process is not one of conversion from N 2 O to NO x , but a parallel process, no correction of<br />

the N 2 O <strong>emissions</strong> is required.<br />

This equation includes the direct NO x <strong>emissions</strong> from fertilisers and the soil only. Other sources such<br />

as tractor exhaust gases are included in the respective inventories.<br />

3 personal communication from Grub, 1996<br />

18


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

2.6 Nutrient Inputs in Agricultural Soils<br />

The input of nutrients (N, P, K, Ca, etc.) into the agricultural soil was not inventoried as <strong>emissions</strong> to<br />

the soil for the following reason: The inventories of agricultural products in ecoinvent data are based<br />

on the fertilising recommendations (Walther et al. 2001). These recommendations in turn are based on<br />

the assumption that the fertiliser should cover the needs of the plants. In a first step, the export of<br />

nutrients through the products (main- and co-products) was calculated. In a second step, the<br />

recommended fertiliser dose was calculated by accounting for various other aspects. The nutrients<br />

supplied to the soil will therefore either be exported in the products or lost to the air or water. The<br />

quantity of nutrients in the soil should not be changed on average in the long term.<br />

2.7 Release of Fossil CO 2 after Urea Applications<br />

During the urea production process, CO 2 is used, which is chemically bound in the urea molecule.<br />

After application and transformation processes in the soil, this CO 2 is released to the atmosphere. Per<br />

kg of applied urea-N, 1570 g of fossil CO 2 are released that are inventoried as “Carbon dioxide, fossil”<br />

to “air, low population density” in ecoinvent data.<br />

2.8 Emissions of Heavy Metals to Agricultural Soil, Surface Water<br />

and Ground Water<br />

According to an analysis of the heavy metals that are causing problems in Swiss agriculture (Kühnholz<br />

2001), the following seven were selected for the inventories in ecoinvent data:<br />

Cadmium (Cd), Chromium (Cr), Copper (Cu), Lead (Pb), Mercury (Hg), Nickel (Ni) and Zinc (Zn).<br />

Typical heavy-metal content of agricultural and non-agricultural soils is given by Desaules &<br />

Dahinden (2000).<br />

Kühnholz (2001) gives a comparison of different emission factors and methods for calculating heavy<br />

metal balances.<br />

The heavy metal <strong>emissions</strong> were calculated by SALCA-heavy metal (Freiermuth 2006). Inputs into<br />

farm land and outputs to surface water and groundwater are calculated on the basis of heavy metal<br />

input from seed, fertilisers, plant protection products and deposition. Residues left on the <strong>field</strong> are not<br />

considered, because they do not leave the system. For erosion of soil average heavy metal contents for<br />

arable land, pastures, meadows and intensive crops are used. The amount of eroded soil is calculated<br />

as for P-<strong>emissions</strong> with the method described in Oberholzer et al. (2006). An allocation factor is used<br />

to distinguish between diffuse and agriculture-related introduction (Freiermuth 2006). We give only a<br />

summary description of the method here. For a full description, the reader is referred to Freiermuth<br />

(2006).<br />

Three types of <strong>emissions</strong> are considered in ecoinvent data:<br />

<br />

<br />

<br />

Leaching of heavy metals to the ground water (always positive values)<br />

Emissions of heavy metals into surface waters through erosion of soil particles (always<br />

positive values)<br />

Emissions of heavy metals to agricultural soil (positive or negative values according to the<br />

results of the balance).<br />

The following sources were used to calculate heavy-metal contents:<br />

<br />

Mineral fertilisers: Desaules & Studer (1993, p. 153), see Tab. A. 2 in the Appendix,<br />

Farmyard manure: Menzi & Kessler (1998) and Desaules & Studer (1993, p. 152), see Tab. A. 3<br />

in the Appendix,<br />

19


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

pesticides: FAW & BLW (2000),<br />

<br />

biomass (seed and products from plant production): Houba & Uittenbogaard (1994, 1995, 1996 &<br />

1997), von Steiger & Baccini (1990) and Wolfensberger & Dinkel (1997); Bennett et al. (2000) &<br />

for Nickel Teherani (1987) for rice; generic mean of biomass for cotton due to lack of data with<br />

mass allocation to fibre and seed (Freiermuth 2006); see Tab. A. 1 in the Appendix. For grass<br />

seed, the values of wheat grains were used; for clover seed, the values of protein peas.<br />

Heavy metal <strong>emissions</strong> into ground and surface water (in case of drainage) are calculated with<br />

constant leaching rates as:<br />

M leach i = m leach i * A i<br />

M leach i<br />

agricultural related heavy metal i emission<br />

m leach i average amount of heavy metal emission (Tab. 2.18)<br />

A i<br />

allocation factor for the share of agricultural inputs in the total inputs for heavy metal i<br />

Tab. 2.18 Heavy metal leaching to groundwater according to Wolfensberger & Dinkel (1997).<br />

Cd Cu Zn Pb Ni Cr Hg<br />

mg/ha/year 50 3600 33000 600 n.a. 21200 1.3<br />

Heavy metal <strong>emissions</strong> through erosion are calculated as follows:<br />

M erosion i = c tot i * B * a *f erosion * A i<br />

M erosion agricultural related heavy metal <strong>emissions</strong> through erosion [kg ha -1 a -1 ]<br />

c tot i<br />

total heavy metal content in the soil (Keller & Desaules 2001, see Tab. 2.19 [kg/kg])<br />

B amount of soil erosion according to Oberholzer et al. (2006) [kg ha -1 a -1 ]<br />

a accumulation factor 1.86 (according to Prasuhn 2006 for P) [-]<br />

f erosion erosion factor considering the distance to river or lakes with an average value of 0.2<br />

(considers only the fraction of the soil that reaches the water body, the rest is<br />

deposited in the <strong>field</strong>) [-]<br />

A i<br />

allocation factor for the share of agricultural inputs in the total inputs for heavy metal i<br />

[-]<br />

Tab. 2.19 Heavy metal contents in mg per kg soil (from Keller & Desaules 2001).<br />

Land use<br />

Cd<br />

[mg/kg]<br />

Cu<br />

[mg/kg]<br />

Zn<br />

[mg/kg]<br />

Pb<br />

[mg/kg]<br />

Ni<br />

[mg/kg]<br />

Cr<br />

[mg/kg]<br />

Hg<br />

[mg/kg]<br />

Permanent grassland 0.309 18.3 64.6 24.6 22.3 24.0 0.088<br />

Arable land 0.24 20.1 49.6 19.5 23.0 24.1 0.073<br />

Intensive crops 0.307 39.2 70.1 24.9 24.8 27.0 0.077<br />

The balance of all inputs into the soil (fertilisers, pesticides, seed and deposition) and outputs from the<br />

soil (exported biomass, leaching and erosion), multiplied by the allocation factor is calculated as an<br />

emission to agricultural soil.<br />

M soil i = (Σ inputs i - Σ outputs i ) * A i<br />

Some of the values for <strong>emissions</strong> of heavy metals to the soil are negative. This means that more heavy<br />

metals are exported than imported. It must, however, be borne in mind that these heavy metals are<br />

transferred either to the water bodies or to the products harvested from the <strong>field</strong> (food, feed and straw).<br />

20


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - <strong>Direct</strong> Field Emissions<br />

A certain fraction of the heavy metal input into the soil stems from atmospheric deposition. The<br />

deposition would occur even without any agricultural production and is therefore not charged to the<br />

latter. An allocation factor accounts for this. The farmer is therefore responsible for a part of the inputs<br />

only (the rest stems mainly from other economic sectors), therefore only a part of the <strong>emissions</strong> is<br />

calculated in the inventory.<br />

A i = M agro i / (M agro i + M deposition i )<br />

A i<br />

allocation factor for the share of agricultural inputs in the total inputs for heavy metal i<br />

M agro i total input of heavy metal from agricultural production in mg/(ha*year) (fertilisers +<br />

seeds + pesticides)<br />

M deposition i total input of heavy metal from atmospheric deposition in mg/(ha*year) (Tab. 2.20)<br />

In cases, where M agro i = 0, i.e. no agricultural inputs to the soil occur, A i also becomes 0.<br />

Tab. 2.20 Heavy metal deposition (see Freiermuth 2006).<br />

Cd Cu Zn Pb Ni Cr Hg<br />

Deposition<br />

[mg/ha/year] 700 2400 90400 18700 5475 3650 50<br />

2.9 Emissions of Pesticides to Agricultural Soil<br />

All pesticides applied for crop production were assumed to end up as <strong>emissions</strong> to the soil. The<br />

amounts of pesticides used as inputs were thus simultaneously calculated as outputs (<strong>emissions</strong> to<br />

agricultural soil). For many active ingredients there are no own LCIs; in these cases, the amounts of<br />

active ingredients are aggregated and inventoried by their chemical class, for which an LCI exists, as<br />

assigned in Sutter (2010, Tab. 2.25). As <strong>emissions</strong>, though, the active ingredients appear under their<br />

specific name. Only for the inputs “pesticides, unspecified”, “fungicides, unspecified” and<br />

“insecticides, unspecified”, no corresponding emission flow could be assigned. Field <strong>emissions</strong><br />

resulting from these admittedly small quantities of substances were thus not considered.<br />

21


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Natural Ressources<br />

3 Natural Ressources<br />

3.1 CO 2 from the Atmosphere<br />

The CO 2 bound from atmosphere is considered a <strong>natural</strong> resource and is represented in the datasets as<br />

the exchange with the environment “carbon dioxide, in air”. Only harvested biomass is accounted for<br />

in this quantity, i.e. products and by-products. Moreover, the CO 2 content of the planted seeds was<br />

subtracted from the CO 2 content of the products in order to avoid double counting. Crop residues<br />

remaining in the <strong>field</strong> are not considered, since these usually decompose within a few years. The<br />

change in soil organic-matter content was not considered either, i.e. the organic C-content of the soil<br />

was assumed to be constant. Exceptions are cases, where a land use change occurred and the C-content<br />

of the soil is decreasing.<br />

The binding of CO 2 from the atmosphere was estimated from the C-content in dry matter multiplied by<br />

the stoichiometric factor 44/12, based on the assumption that the carbon in the biomass is completely<br />

sourced from the air. The references of C-content of products and seeds are given in the respective<br />

datasets („exchange properties‟). Basically, if no direct reference of a C-content could be found, it was<br />

estimated from the composition of the respective biomass assuming the following C-contents of the<br />

components (in dry mass): 44% in carbohydrates (including fibres), 75% in fats and 0% in ash 4 ; 53%<br />

in proteins (Rouwenhorst et al. 1991).<br />

The basic form of the formula for the calculation of “carbon dioxide, in air” is:<br />

44/12 * (RP.C_content * RP.amount * RP.DM<br />

+ (BP_1.C_content * BP _1.amount * BP_1.DM + … + BP_X.C_content * BP_X.amount * BP_X.DM)<br />

- (SD_1.C_content * SD_1.amount * SD_1.DM +… + SD_X.C_content * SD_2.amount * SD_X.DM) )<br />

where RP represents the reference product, BP_X the by-products, and SD_X the seed inputs; C_content is<br />

the non-fossil C-content [kg C/kg dry mass], amount is the absolute amount of the flow of product or<br />

seed [kg DM; kg FM; unit; ...], and DM is the dry matter in one unit of the respective flow [kg/unit].<br />

Attention must be paid when applying these datasets in life cycle studies (e.g. if straw is combusted to<br />

produce heat or food products are consumed): the CO 2 released from the agricultural products and byproducts<br />

must be considered as an emission of biogenic CO 2 , CO, CH 4 or other C-compounds.<br />

3.2 Land Use<br />

Land occupation was calculated from the duration of land use (taking account of the time from soil<br />

cultivation until harvest), and from the yield per area unit, if the reference function was kg of product<br />

instead of ha. Different categories of land occupation were used depending on crop and country<br />

specific characteristics (see Tab. 3.1; for details on irrigation refer to documentation of inputs from<br />

technosphere of the respective crop dataset); extensive and organic production was classiefied as<br />

„extensive‟ land use, intensive integrated and conventional production as „intensive‟ land use. The<br />

duration of land use considered for annual crops varies (either from sowing to harvest or 12 months)<br />

and can be obtained through the ratio land occupation/land transformation. For permanent crops a<br />

duration of 12 months is used per crop year.<br />

Land transformation was calculated on the basis of the area required to produce 1 kg of product. In the<br />

case of 1 ha as a reference unit, areas of preceding and current land use sum up to 10‟000 m 2 , each.<br />

For permanent crops the amounts of transformed land are divided by the lifetime of the crop, e.g. 28<br />

years for oil palm plantations. The current land use form corresponds to the categories listed for land<br />

4 Personal communication from Jens Leifeld, ART, 23 April 2002.<br />

22


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Natural Ressources<br />

occupation in Tab. 3.1. The preceding land use form depends on crop and country specific<br />

characteristics:<br />

<br />

<br />

<br />

For Swiss arable crops and temporary grassland (CH) the preceding land use form was<br />

assumed to be 71% arable land (“transformation, from annual crop, non-irrigated”) and 29%<br />

meadow (sown on arable land; “transformation, from pasture, man made”) for all winter<br />

crops. These percentages correspond to the proportions of arable crops and leys out of the total<br />

arable surface in Switzerland (293,000 ha arable crops (71%), 118,000 ha leys (29%), 411,000<br />

ha total (100%) arable surface in 2000), taken from BLW (2001, p. A4). The type of use<br />

before establishment of the crop Green manure is not established after meadow or pasture (as<br />

this would cause the meadow to assume the function of a green manure), but is always<br />

established between two arable crops. Land transformation to green manure was therefore<br />

calculated 100% as “transformation, from annual crop, non-irrigated”. The spring-sown crops<br />

were assumed to follow a green manure. In these cases too, land transformation was calculated<br />

as 100% “transformation, from arable, non-irrigated”. Specifications of extensive and<br />

intensive land use follow the same pattern as for land occupation (see Tab. 3.1).<br />

For Swiss permanent grassland (CH) it was assumed that land use is contstant and<br />

grasslands are not being transformed from other land uses. In fact this corresponds to the<br />

current situation in Switzerland. Specifications of extensive and intensive land use follow the<br />

same pattern as for land occupation (see Tab. 3.1).<br />

For arable crops in Europe (DE, FR, ES) crop rotations were assumed that did not include<br />

grassland and where all crops were produced in conventional, non-irrigated systems. Hence<br />

the preceding land use was always classified as “transformation, from annual crop, nonirrigated,<br />

intensive”.<br />

For rye in Europe (RER) it was assumed that transformed land originally consisted of 71%<br />

annual crops and 29 % temporary grassland (grown on arable land). The percentages are based<br />

on German agricultural statistics (Statistitisches Bundesamt 2003).<br />

<br />

<br />

<br />

<br />

For energy crops in Germany (DE) (mischanthus, willow in short rotation coppice, as well<br />

as mischanthus rhizome for propagation) it was assumed that land use was originally arable<br />

production, but not further specified. For willow stem cuttings (DE) it was assumed that land<br />

use was originally an annual crop (non-irrigated, intensive).<br />

For arable crops in USA and China (US & CN) crop rotations were assumed that did not<br />

include grassland. Hence, the preceding land use was always classified as “transformation,<br />

from annual crop”. No specifications were made with respect to irrigation, as non-irrigated<br />

crops may precede irrigated crops and vice versa.<br />

For soybean in Brazil (BR) the original land use and respective fractions of transformed land<br />

were calculated as shown in Tab. 3.2. The fractions of land transformed from non-arable areas<br />

(land use change) are summarised in the exchange „transformation, from cropland fallow<br />

(non-use)‟ and listed in detail as inputs from technosphere („land, recently transformed from<br />

forest, year 1‟, etc.). For details of accounting for land use change and related <strong>emissions</strong> see<br />

“Guidlines_LUC_Calcs" - <strong>pdf</strong>-document on the dedicated talk page of ecoinvent<br />

(www.ecoinvent.org/documentation).<br />

For sugarcane in Brazil (BR) the original land use was assumed to be sclerophyllous<br />

shrubland for 0.97% of the sugarcane area, the remainder area was assigned to annual crop,<br />

non-irrigated. The 0.97% correspond to the annual expansion rate of the sugarcane area in<br />

Brazil (Mathias 2005a & 2005b). This expansion is assumed to occur on shrubland because an<br />

expansion into tropical rainforest areas is unlikely due to the wet climate and weak<br />

infrastructure, unsuitable soils and high production costs (J. Granelli (José Granelli & Filhos<br />

Ltds), personal communication, 2005; D. Aronson (Petrobras), personal communication,<br />

2005; R.B. Ortolan (agronomist at Copercana), personal communication, 2005). The fractions<br />

of land transformed from non-arable areas (land use change) are summarised in the exchange<br />

„transformation, from cropland fallow (non-use)‟ and listed in detail as inputs from<br />

technosphere („land, recently transformed from forest, year 1‟, etc.). For details of accounting<br />

23


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Natural Ressources<br />

<br />

for land use change and related <strong>emissions</strong> see “Guidlines_LUC_Calcs" - <strong>pdf</strong>-document on the<br />

dedicated talk page of ecoinvent (www.ecoinvent.org/documentation).<br />

For oil palm plantations in Malaysia (MY) it was assumed that 100% of the area were being<br />

transformed from tropical rainforest. This assumption is based on the rapid expansion of palm<br />

oil plantations in the recent years in Malaysia (150,000 ha in 10 years, USDA 2004c). The<br />

fractions of land transformed from non-arable areas (land use change) are summarised in the<br />

exchange „transformation, from cropland fallow (non-use)‟ and listed in detail as inputs from<br />

technosphere („land, recently transformed from forest, year 1‟, etc.). For details of accounting<br />

for land use change and related <strong>emissions</strong> see “Guidlines_LUC_Calcs" - <strong>pdf</strong>-document on the<br />

dedicated talk page of ecoinvent (www.ecoinvent.org/documentation).<br />

Tab. 3.1<br />

Categories of land occupation as applied by country and crop. SIP = Swiss Integrated Production.<br />

Country Crop Category Comment<br />

CH<br />

CH<br />

CH<br />

CH<br />

Europe<br />

(RER, DE,<br />

FR, ES)<br />

DE<br />

DE<br />

arable crops (SIP<br />

extensive & organic)<br />

arable crops (SIP<br />

intensive)<br />

grassland production<br />

(SIP/organic,<br />

extensive)<br />

grassland production<br />

(SIP/organic,<br />

intensive)<br />

arable crops<br />

(conventional), incl.<br />

willow stem cutting<br />

production<br />

perenniel energy crops<br />

(willow in short rotation<br />

coppice, miscanthus &<br />

miscanthus rhizome)<br />

willow stem cutting<br />

production<br />

occupation, annual crop, nonirrigated,<br />

extensive<br />

occupation, annual crop, nonirrigated,<br />

intensive<br />

occupation, pasture, man<br />

made, extensive<br />

occupation, pasture, man<br />

made, intensive<br />

occupation, annual crop, nonirrigated,<br />

intensive<br />

occupation, permanent crop,<br />

non-irrigated, intensive<br />

occupation, annual crop, nonirrigated,<br />

intensive<br />

US cotton, potato, wheat occupation, annual crop Partly irrigated.<br />

US rice occupation, annual crop,<br />

irrigated, intensive<br />

US rape seed, soybean occupation, annual crop, nonirrigated,<br />

intensive<br />

All Swiss crops are assumed not to be<br />

irrigated.<br />

All Swiss crops are assumed not to be<br />

irrigated.<br />

All Swiss grasslands are assumed not<br />

to be irrigated. Persistence of extensive<br />

permanent grassland: 50 years.<br />

All Swiss grasslands are assumed not<br />

to be irrigated. Persistence of intensive<br />

permanent grassland: 20 years;<br />

temporary grassland: 3 years. Note that<br />

temporary grassland is always<br />

considered intensive, also in organic<br />

farming.<br />

All European arable crops are assumed<br />

not to be irrigated.<br />

All German arable crops are assumed<br />

not to be irrigated.<br />

An annual production system is<br />

assumed; non irrigated.<br />

100% of rice in US is assumed to be<br />

irrigated.<br />

No irrigation.<br />

MY palm fruit bunches occupation, forest, intensive 100% of oil palm plantations in MY are<br />

assumed to be irrigated.<br />

BR soybean, sugarcane occupation, annual crop, nonirrigated,<br />

intensive<br />

CN<br />

cotton<br />

sweet sorghum<br />

occupation, annual crop,<br />

irrigated, intensive<br />

Non-irrigated production is assumed for<br />

sugarcane and soybean for the whole<br />

of BR.<br />

100% of cotton and sweet sorghum in<br />

CN is assumed to be irrigated.<br />

24


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Natural Ressources<br />

Tab. 3.2<br />

Calculation of transformed land use categories for soybean cultivation in Brazil, taken from Jungbluth et al.<br />

2007 (calculation based on USDA 2004b, Bickel & Dros 2003)<br />

Land use Brazil total South Brazil North Brazil<br />

total area in 2004 [Million ha] 23.5 11.0 12.5<br />

total area in 2003 [Million ha]<br />

(Total are in 2004 – rise per year)<br />

21.8 10.6 11.2<br />

Rise of the total area [Million ha]<br />

In the last 5 years:<br />

6.1. Million ha in North Brazil<br />

1.7 0.5 1.2<br />

2.3 Million ha in South Brazil<br />

% of total cultivated area in Brazil 47 53<br />

Transformation from arable area [Million ha] 21.5 10.6 10.9<br />

Transformation to pasture [Million ha]<br />

(rise per year * 49% / 2 years)<br />

0.299 0 0.299<br />

New area [% of the total cultivated area]<br />

(rise of the total area + transformation to pasture)<br />

8.4 4.2 12.2<br />

From rainforest [% of the new cultivated area] 0 49<br />

From Cerrado Ecosystems [% of the new cultivated area] 100 51<br />

Transformation from tropical rainforest [Million ha] 0.74 0 0.74<br />

Transformation from shrub land [Million ha] 1.23 0.46 0.77<br />

Transformation from arable area [Million ha] 21.52 10.58 10.94<br />

Transformation from tropical rainforest<br />

[% of the total cultivated area]<br />

3.2 0 5.98<br />

Transformation from shrub land<br />

[% of the total cultivated area]<br />

5.2 4.2 6.2<br />

Transformation from arable area<br />

[% of the total cultivated area]<br />

91.6 95.8 87.8<br />

25


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Appendix A<br />

Appendix A<br />

Tab. A. 1 Heavy-metal contents of plant material (mg/kg dry matter, from Freiermuth 2006).<br />

Cd Cu Zn Pb Ni Cr Hg<br />

[mg/kg DM] [mg/kg DM] [mg/kg DM] [mg/kg DM] [mg/kg DM] [mg/kg DM] [mg/kg DM]<br />

Generic mean 0.10 6.6 32.0 0.54 1.04 0.55 0.04<br />

Grass / Hay 0.13 8.6 40 1.2 1.68 1.09 0.15<br />

Maize grains 0.03 2.5 21.5 0.3 1.16 0.32 0<br />

Maize silage 0.1 5 34.5 1.61 0.48 0.7 0.01<br />

Wheat grains 0.1 3.3 21.1 0.2 0.2 0.2 0.01<br />

Wheat straw 0.2 2.5 9.6 0.6 0.6 0.7<br />

Barley grains 0.03 4.3 26.6 0.2 0.1 0.1<br />

Barley straw 0.1 4.8 11.1 0.6 0.8 1.2<br />

Rye straw 0.1 3.2 13 0.4 0.7 0.5<br />

Potatoes 0.04 6.45 15 0.55 0.33 0.57 0.09<br />

Rape seed 1.6 3.3 48 5.25 2.6 0.5 0.1<br />

Faba beans 0.04 6 30.1 0.87 1.3 0.69 0<br />

Soya beans 0.06 15.1 47.7 0.08 5.32 0.52 0<br />

Protein peas 0.09 10 73 0.16 0.83 0.32 0.01<br />

Sugar beets 0.4 12 36.4 1.16 1.08 1.775 0.095<br />

Rice grains 0.02 5.27 43.9 0.96 0.97 0.49<br />

26


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Appendix A<br />

Tab. A. 2 Heavy-metal contents of mineral fertilisers (mg/kg nutrient) according to Desaules & Studer (1993). No data available on Hg. Source: Freiermuth (2006).<br />

Cd Cu Zn Pb Ni Cr<br />

mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg<br />

Mineral fertilisers (%N/%P2O5/%K2O/%Mg) nutrient nutrient nutrient nutrient nutrient nutrient<br />

Urea (46/0/0) kg N 0.11 13.04 95.65 2.39 4.35 4.35<br />

Calcium ammonium nitrate (20/0/0) kg N 0.25 60.00 155.00 5.50 90.00 10.00<br />

Ammonium nitrate (27.5/0/0) kg N 0.18 25.45 181.82 6.91 47.27 14.55<br />

Ammonium sulphate (21/0/0) kg N 0.24 19.05 142.86 5.24 8.57 9.52<br />

Calcium ammonium nitrate (27/0/0) kg N 0.19 8.52 100.00 5.93 12.59 2.96<br />

Magnesium ammonium nitrate (23/0/0/5) kg N 0.43 56.52 4.35 4.35 21.74 6.09<br />

Generic mean N 0.21 22.25 121.43 5.37 17.17 7.81<br />

Triple superphosphate (0/46/0) kg P2O5 113.04 97.83 650.00 7.61 95.65 567.39<br />

Superphosphate (0/19/0) kg P2O5 52.63 121.05 852.63 578.95 105.26 342.11<br />

Thomas meal (0/16/0) kg P2O5 1.56 250.00 425.00 75.00 125.00 12212.50<br />

Hyperphosphate/raw phosphate (0/26/0) kg P2O5 50.00 115.38 915.38 23.85 76.92 611.54<br />

Generic mean P 51.32 118.22 751.32 49.42 100.46 589.46<br />

Potassium chloride (KCl) (0/0/60) kg K2O 0.10 8.33 76.67 9.17 3.50 3.33<br />

Potassium sulphate (0/0/50) kg K2O 0.10 4.00 64.00 6.60 1.60 4.00<br />

Raw potassium (0/0/26/5) kg K2O 0.19 173.08 153.85 11.54 11.54 173.08<br />

Lime kg CaO 0.12 4.00 8.00 3.60 12.20 314.00<br />

Generic mean K 0.11 6.17 70.33 7.88 7.52 88.54<br />

27


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Appendix A<br />

Tab. A. 3 Heavy-metal contents of farmyard manure and organic fertilisers (g/unit, compiled by Freiermuth 2006 from from Menzi & Kessler (1998) and Desaules & Studer (1993, p.<br />

152)). Dry matter (DM) contents from Walther et al. (2001, Tab. 44).<br />

Cd Cu Zn Pb Ni Cr Hg<br />

Farmyard manure<br />

[mg/kg DM] [mg/kg DM] [mg/kg DM] [mg/kg DM] [mg/kg DM] [mg/kg DM] [mg/kg DM] DM-content<br />

Cattle liquid manure 0.178 37.1 162.2 3.77 4.3 3.9 0.4 9.0%<br />

Cattle slurry 0.16 19.1 123.3 2.92 3.1 2.1 0.6 7.5%<br />

Cattle staple manure 0.172 23.9 117.7 3.77 4.3 3.9 0.4 19.0%<br />

Cattle manure form loose housing 0.151 22.0 91.1 2.81 4.3 3.9 0.4 21.0%<br />

Pig liquid manure 0.21 115.3 746.5 1.76 8.6 6.7 0.8 5.0%<br />

Pig solid manure 0.21 115.3 746.5 1.76 8.6 6.7 0.8 27.0%<br />

Litter from broilers 0.292 43.8 349.2 2.92 40 10 0.2 65.0%<br />

Litter from belts from laying hens 0.2525 39.6 468.4 2.235 7.9 5.5 0.2 30.0%<br />

Litter from deep pits from laying hens 0.2525 39.6 468.4 2.235 7.9 5.5 0.2 45.0%<br />

28


Literature<br />

<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Literature<br />

Agrammon Group 2009a<br />

Agrammon Group 2009b<br />

Asman 1992<br />

Audsley et al. 1997<br />

Agrammon Group (2009) Technical process description AGRAMMON – Draft.<br />

Online at: www.agrammon.ch.<br />

Agrammon Group (2009) Technische Parameter Modell Agrammon.<br />

Schweizerische Hochschule für Landwirtschaft SHL. Online at:<br />

www.agrammon.ch.<br />

Asman W.A.H. (1992) Ammonia emission in Europe: updated emission and<br />

emission variations, Rep. 228471008, National Inst. of Public Health and<br />

Environmental Protection, Bilthoven.<br />

Audsley E., Alber S., Clift R., Cowell S., Crettaz P., Gaillard G., Hausheer J.,<br />

Jolliet O., Kleijn R., Mortensen B., Pearce D., Roger E., Teulon H., Weidema B.<br />

and van Zeijts H. (1997) Harmonisation of environmental life cycle assessment<br />

for agriculture. Final Report Concerted Action AIR3-CT94-2028. Silsoe<br />

Research Insitute, Silsoe, UK.<br />

Batjes 2008 Batjes N.H. (2008) ISRIC-WISE Harmonized Global Soil Profile Dataset (Ver. 3.1).<br />

Report 2008/02, ISRIC – World Soil Information, Wageningen (with dataset).<br />

Available at:<br />

http://www.isric.org/isric/webdocs/docs//ISRIC_Report_2008_02.<strong>pdf</strong>?q=isric/webdo<br />

cs/Docs/ISRIC_Report_2008_02.<strong>pdf</strong>.<br />

Bennett et al. 2000<br />

Bickel & Dros 2003<br />

BLW 2003<br />

Boquet & Breitenbeck 2000<br />

Brisson et al. 2003<br />

de Willigen 2000<br />

Bennett J.P., Chiriboga, E., Colemann, J. & Waller, D.M (2000) Heavy metals in<br />

wild rice from northern Wisconsin, The Science of the Total Environment 246,<br />

261-269.<br />

Bickel U. & Dros J.M. (2003) The impacts of soybean cultivation on Brazilian<br />

ecosystems. Three case studies. World Wildlife Fund. Forest Conversion Initiative.<br />

Bundesamt für Landwirtschaft (2003) Agrarbericht 2003. Bundesamt für<br />

Landwirtschaft BLW, Bern, Schweiz. Retrieved March 8, 2011 from<br />

http://www.blw.admin.ch/dokumentation/00018/00498/index.html?lang=de.<br />

Boquet D.J. & Breitenbeck G.A. (2000) Nitrogen rate effect on partitioning of<br />

nitrogen and dry matter by cotton. Crop Science 140, 1685-1693.<br />

Brisson N., Gary C., Justes E., Roche R., Mary B., Ripoche D., Zimmer D.,<br />

Sierra J., Bertuzzi P., Burger P., Bussière F., Cabidoche Y.M., Cellier P.,<br />

Debaeke P., Gaudillère J.P., Hénault C., Maraux F., Seguin B & Sinoquet H.,<br />

2003. An overview of the crop model STICS. European Journal of Agronomy<br />

18, 309–332.<br />

de Willigen P. (2000) An analysis of the calculation of leaching and<br />

denitrification losses as practised in the NUTMON approach. Plant Research<br />

International, Report 18, Wageningen, Netherlands.<br />

Desaules & Dahinden 2000 Desaules A. & Dahinden R. (2000) Nationales Bodenbeobachtungsnetz –<br />

Veränderungen von Schadstoffgehalten nach 5 und 10 Jahren. BUWAL,<br />

Schriftenreihe Umwelt Nr. 320, 129 p.<br />

Desaules & Studer 1993<br />

Diepenbrock et al. 1995<br />

Desaules A. & Studer K. (1993) NABO: Nationales Beobachtungsnetz,<br />

Messresultate 1985-1991, Schriftenreihe Umwelt Nr. 200, BUWAL (Bundesamt<br />

für Umwelt, Wald und Landschaft), Bern.<br />

Diepenbrock W., Pelzer B. & Radtke J. (1995) Energiebilanz im<br />

Ackerbaubetrieb. Arbeitspapier 211. Kuratorium für Technik und Bauwesen in<br />

der Landwirtschaft (KTBL). Darmstadt, Deutschland.<br />

29


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Literature<br />

Dong et al. 2010<br />

Dong H., Kong X., Li W., Tang W. & Zhang D. (2010) Effects of plant density<br />

and nitrogen and potassium fertilization on cotton yield and uptake of major<br />

nutrients in two <strong>field</strong>s with varying fertility. Field Crops Research 119, 106-113.<br />

Eggleston et al. 2006 Eggleston H.S., Buendia, L., Miwa K., Ngara T. & Tanabe K. (Eds.) (2006)<br />

2006 IPCC Guidelines for National Greenhouse Gas Inventories. IPCC National<br />

Greenhouse Gas Inventories Programme, Hayama, Japan.<br />

Faist Emmenegger et al. 2009 Faist Emmenegger M., Reinhard J. & Zah R. (2009) Sustainability Quick Check<br />

for Biofuels – intermediate background report. With contributions from T. Ziep,<br />

R. Weichbrodt, Prof. Dr. V. Wohlgemuth, FHTW Berlin and A. Roches, R.<br />

Freiermuth Knuchel, Dr. G. Gaillard, Agroscope Reckenholz-Tänikon.<br />

Dübendorf, Switzerland.<br />

FAO 2001<br />

FAO 2011<br />

FAO (2001) Global Ecological Zoning for the Global Forest Resources<br />

Assessment 2000. Forestry Department, Food and Agriculture Organization of<br />

the United Nations. Rome, Italy.<br />

FAO (2011) Crop water information. Natural Resources and Environment<br />

Department, Food and Agriculture Organization of the United Nations. Online,<br />

accessed February 2011. Available at:<br />

http://www.fao.org/nr/water/cropinfo.html.<br />

FAT 2000a<br />

FAW & BLW 2000<br />

FAT (2000a) Bericht über biologisch bewirtschaftete Betriebe 1999 – Ergebnisse<br />

der Zentralen Auswertung von Buchhaltungsdaten, Nr. 10, Oktober 2000. FAT<br />

Taenikon, 28p.<br />

Forschungsanstalt für Obst-, Wein- und Gartenbau Wädenswil and Bundesamt<br />

für Landwirtschaft (eds.) (2000) Pflanzenschutzmittel. Verzeichnis 2000.<br />

Bundesamt für Landwirtschaft BLW, Bern, Schweiz.<br />

Flisch et al. 2009 Flisch, R., Sinaj, S., Charles, R. & Richner, W., 2009. GRUDAF 2009 -<br />

Grundlagen für die Düngung im Acker und Futterbau. Agrarforschung 16 (2), 1-<br />

97.<br />

Freiermuth 2006<br />

Freiermuth R. (2006) Modell zur Berechnung der Schwermetallflüsse in der<br />

Landwirtschaftlichen Ökobilanz - SALCA-Schwermetall, Forschungsanstalt<br />

Agroscope Reckenholz-Tänikon (ART), 28p. Online at<br />

http://www.agroscope.admin.ch/oekobilanzen/01197.<br />

Greber et al. 2002 Greber E., Baumann A., Cornaz S., Herold T., Kozel R., Muralt, R. & Zobrist, J.<br />

(2002) Grundwasserqualität in der Schweiz. NAQUA-Trend - das nationale<br />

Beobachtungsprogramm. Sonderdruck Nr. 1472 aus gwa 3/2002 des<br />

Schweizerischen Vereins des Gas- und Wasserfaches (SVGW), Zürich, 12p.<br />

Retrieved on January 6, 2003 from<br />

http://guf.unibe.ch/dokugs8/SD_1472_2_bis_12.<strong>pdf</strong>?_Publications_from_www.<br />

WATERandFISHERIES.ch.<br />

Goldemberg 2008<br />

Goldemberg J. (2008) The Brazilian biofuels industry. Biotechnology for<br />

Biofuels, 1 (6), online. Available at:<br />

http://www.biotechnologyforbiofuels.com/content/1/1/6.<br />

Houba & Uittenbogaard 1994 Houba V.J.G. & Uittenbogaard J. (1994) Chemical composition of various plant<br />

species. International Plant-Analytical Exchange (IPE). Department of Soil<br />

Science and Plant Nutrition, Wageningen Agricultural University, The<br />

Netherlands.<br />

Houba & Uittenbogaard 1995 Houba V.J.G. & Uittenbogaard J. (1995) International Plant-Analytical<br />

Exchange, Report 1995. International Plant-Analytical Exchange (IPE).<br />

Department of Soil Science and Plant Nutrition, Wageningen Agricultural<br />

University The Netherlands.<br />

30


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Literature<br />

Houba & Uittenbogaard 1996 Houba V.J.G. & Uittenbogaard J. (1996) International Plant-Analytical<br />

Exchange, Report 1996. International Plant-Analytical Exchange (IPE).<br />

Department of Soil Science and Plant Nutrition, Wageningen Agricultural<br />

University The Netherlands.<br />

Houba & Uittenbogaard 1997 Houba V.J.G. & Uittenbogaard J. (1997) International Plant-Analytical<br />

Exchange, Report 1997. International Plant-Analytical Exchange (IPE).<br />

Department of Soil Science and Plant Nutrition,Wageningen Agricultural<br />

University The Netherlands.<br />

Hsu & Gale 2001<br />

Jungbluth et al. 2007<br />

Keller & Desaules 2001<br />

Keskin et al. 2009<br />

Hsu H. & Gale F. (2001) Regional shifts in China‟s cotton production and use.<br />

In: King L.(ed.), Cotton and wool situation and outlook yearbook. Market and<br />

Trade Economics Devision, United States Department of Agriculture –<br />

Economic Research Service, CWS 2001.<br />

Jungbluth N., Chudacoff M., Dauriat A., Dinkel F., Doka G., Faist Emmenegger<br />

M., Gnansounou E., Kljun N., Schleiss K., Spielmann M., Stettler C. & Sutter J.<br />

(2007) Life cycle inventories of bioenergy. ecoinvent report no. 17, Swiss Centre<br />

for Life Cycle Inventories, Dübendorf, Switzerland.<br />

Keller T. & Desaules A. (2001) Böden der Schweiz: Schadstoffgehalte und<br />

Orientierungs-werte (1990 – 1996). Umwelt-Materialien Nr. 139. Bern:<br />

Bundesamt für Umwelt, Wald und Landschaft BUWAL.<br />

Keskin B., Yilmaz I.H., Bozkurt M.A. & Akdeniz H. (2009) Sewage sludge as<br />

nitrogen source for irrigated silage sorghum. Journal of Animal and Veterinary<br />

Advances 8 (3), 573-578.<br />

Khaledian et al. 2010 Khaledian M.R., Maihol J.C., Ruelle P., Mubarak I. & Maraux F. (2010)<br />

Nitrogen balance and irrigation water productivity for corn, sorghum and durum<br />

wheat under direct seeding into mulch when compared with conventional tillage<br />

in the southeastern France. Irrigation Science, online.<br />

Khalid et al. 1999<br />

Kühnholz 2001<br />

Kupper et al. 2010<br />

Khalid H., Zin Z.Z. & Anderson J.M. (1999) Quantification of oil palm biomass<br />

and nutrient value in a mature plantation. I, Above ground biomass. Journal of<br />

Oil Palm Research 2 (1), 23-32.<br />

Kühnholz O. (2001) Schwermetalle in der Ökobilanz von landwirtschaftlichen<br />

Produktionssystemen. Internal Report, FAL, 58p.<br />

Kupper T., Bonjour C., Achermann B., Zaucker F., Rihm B., Nyfeler-Brunner<br />

A., Leuenberger C. & Menzi H. (2010) Ammoniakemissionen in der Schweiz:<br />

Neuberechnung 1990-2007 – Prognose bis 2020. Bundesamt für Umwelt –<br />

Abteilung Luftreinhaltung und NIS, Bern, Switzerland. Available at:<br />

http://www.agrammon.ch/dokumente-zum-download/.<br />

LBL et al. 2000 LBL, SRVA & FiBL (2000) Deckungsbeiträge - Ausgabe 2000.<br />

Maier et al. 1998<br />

Mathias 2005a<br />

Maier J., Vetter R., Siegle V. & Spliethoff H. (1988) Anbau von Energiepflanzen<br />

– Ganzpflanzengewinnung mit verschiedenen Beerntungsmethoden (ein- und<br />

mehrjährige Pflanzenarten); Schwachholzverwertung, Abschlussbericht.<br />

Ministerium Ländlicher Raum Baden-Würtenberg. Stuttgart, Deutschland.<br />

Retrieved on August 23, 2002 from<br />

http://www.inaro.de/download/AB_energiepfloA.<strong>pdf</strong>.<br />

Mathias J. (2005) Anos dourados para a industria de cana. Globo Rural, Ediçao<br />

Especial, 10.<br />

Mathias 2005b Mathias, J. (2005). A refinaria do futuro. Globo Rural, Ediçao Especial, 46.<br />

Menzi & Kessler 1998<br />

Menzi H. & Kessler J. (1998) Heavy metal content of manures in Switzerland.<br />

In: Martinez J. and Maudet M.N. (eds): Proc. 8th International Conference on the<br />

FAO ESCORENA.<br />

31


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Literature<br />

Menzi et al. 1997<br />

Mishra et al. 1997<br />

Möhlmann 2002<br />

Nemecek & Huguenin 2002<br />

Menzi H., Frick R. & Kaufmann R. (1997) Ammoniak-Emissionen in der<br />

Schweiz: Ausmass und technische Beurteilung des Reduktionspotentials.<br />

Schriftenreihe der FAL 26, Zürich-Reckenholz.<br />

Mishra H.S., Rathore T.R. & Pant R.C. (1997) Root growth, water potential, and<br />

yield of irrigated rice. Irrigation Science 17, 69-75.<br />

Möhlmann O. (2002) Baumwolle. GRIN Verlag.<br />

Nemecek T. & Huguenin O. (2002) Beurteilung von Graslandsystemen. In:<br />

Ökobilanzen: Beitrag zu einer nachhaltigen Landwirtschaft, FAL-Schriftenreihe<br />

38, 16-18.<br />

Nemecek et al. 2005 Nemecek T., Huguenin-Elie O., Dubois D. & Gaillard G., 2005.<br />

Ökobilanzierung von Anbausystemen im schweizerischen Acker- und Futterbau.<br />

Agroscope FAL Reckenholz, Zürich; Schriftenreihe der FAL 58, 155 p.<br />

Nemecek et al. 2007<br />

Oberholzer et al. 2001<br />

Nemecek T., Kägi T. & Blaser S. (2007) Life cycle intentories of agricultural<br />

production systems. Final report ecoinvent v2.0 No. 15. Swiss Centre for Life<br />

Cycle Inventories, Dübendorf, Switzerland.<br />

Oberholzer B., Poser K., Dill A. & Herzog F. (2001) Kann die<br />

Nitratauswaschung zuverlässig simuliert werden? In: Neue Erkenntnisse zu<br />

Stickstoffflüssen im Ackerbau, FAL-Tagung 6.4.2001, 8p.<br />

Oberholzer et al. 2006 Oberholzer H.R., Weisskopf P., Gaillard G., Weiss F. & Freiermuth, R. (2006)<br />

Methode zur Beurteilung der Wirkungen landwirtschaftlicher Bewirtschaftung<br />

auf die Bodenqualität in Ökobilanzen – SALCA-SQ. Agroscope FAL<br />

Reckenholz, online at<br />

http://www.art.admin.ch/themen/00617/00744/index.html?lang=en.<br />

Prasuhn 2006<br />

Prasuhn & Grünig 2001<br />

Qiuxia et al. 2005<br />

RAP 1999<br />

Richner et al. in prep.<br />

Prasuhn V. (2006) Erfassung der PO 4 -Austräge für die Ökobilanzierung SALCA<br />

Phosphor. Agroscope Reckenholz - Tänikon ART, 20p. Online at<br />

http://www.art.admin.ch/themen/00617/00744/index.html?lang=en.<br />

Prasuhn V. & Grünig K. (2001) Evaluation der Ökomassnahmen<br />

Phosphorbelastung der Oberflächengewässer durch Bodenerosion. Schriftenreihe<br />

der FAL 37, 151p.<br />

Qiuxia H., Qifa Z., Xuemei S. (2005) Strikingly high content of grain protein in<br />

solution-cultured rice, Journal of the Science of food and Agriculture, 85 (7),<br />

1197-1202.<br />

RAP (1999) Fütterungsempfehlungen und Nährwerttabellen für Wiederkäuer.<br />

4th ed., LmZ, Zollikofen. Command at:<br />

http://combi.agri.ch/lmz/lehrbuch/tier.htm.<br />

Richner W., Oberholzer H.R., Freiermuth Knuchel R., Huguenin O., Ott S. &<br />

Walther U. (in prep.) Modell zur Beurteilung der Nitratauswaschung in<br />

Ökobilanzen – SLACA-NO3, Agroscope Reckenholz - Tänikon ART, 27p. To<br />

be published at: www.agroscope.ch.<br />

Rouwenhorst et al. 1991 Rouwenhorst R.J., Jzn J.F., Scheffers W.A. & Vandijken J.P. (1991)<br />

Determination of protein-concentration by total organic-carbon analysis. Journal<br />

of Biochemical and Biophysical Methods 22 (2), 119-128.<br />

Roy et al. 2003<br />

Scheffer 2002<br />

Roy R. N., Misra R.V., Lesschen J.P. & Smaling E.M. (2003). Assessment of<br />

soil nutrient balance: approaches and methodologies. Food and Agriculture<br />

Organization of the United Nations. Rome, Italy.<br />

Scheffer F. (2002) Lehrbuch der Bodenkunde / Scheffer/Schachtschabel. 15th<br />

ed, Spektrum Akademischer Verlag, Heidelberg, Germany.<br />

32


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Literature<br />

Schmid & Prasuhn 2000<br />

Schmid et al. 2000<br />

SHL 2010<br />

Stauffer et al. 2001<br />

Surbeck & Leu 1998<br />

Schmid C. & Prasuhn V. (2000) GIS-gestützte Abschätzung der Phosphor- und<br />

Stickstoffeinträge aus diffusen Quellen in die Gewässer des Kantons Zürich.<br />

Schriftenreihe der FAL 35, 114p.<br />

Schmid M., Neftel A. & Fuhrer J. (2000) Lachgasemissionen aus der Schweizer<br />

Landwirtschaft. Schriftenreihe der FAL 33, 131 p.<br />

SHL (2010) Eingabeparameter der Hochrechnungen 1990, 1995, 2002, 2007 (rev<br />

2010-06-21). Schweizerische Hochschule für Landwirtschaft. Online, available<br />

at: http://www.agrammon.ch/dokumente-zum-download/.<br />

Stauffer W., Prasuhn V. & Spiess E. (2001) Einfluss unterschiedlicher<br />

Fruchtfolgen auf die Nitratauswaschung. In: Neue Erkenntnisse zu<br />

Stickstoffflüssen im Ackerbau, FAL-Tagung 6.4.2001, 8p.<br />

Surbeck A. & Leu D. (1998) Toxikologische Beurteilung von Nitrat im<br />

Trinkwasser. In: Scholz R.W., Bösch S., Mieg H.A. und Stünzi J. (eds.): Region<br />

Klettgau - Verantwortungsvoller Umgang mit Boden. ETH-UNS-Fallstudie '97,<br />

Verlag Rüegger, Zürich. 203-205.<br />

Statistisches Bundesamt 2003 Statistisches Bundesamt (Ed) (2003) Statistisches Jahrbuch 2003. Wiesbaden<br />

(Germany).<br />

Sutter 2010<br />

Swain et al. 2006<br />

Teherani 1987<br />

Thöni et al. 2007<br />

USDA 1999<br />

USDA 2004a<br />

Sutter J. (2010) Life Cycle Inventories of Pesticides. Swiss Centre for Life Cycle<br />

Inventories, St. Gallen, Switzerland.<br />

Swain D.K., Bhaskar B.C., Krishnan P., Rao K.S., Nayak S.K. & Dash R.N.<br />

(2006) Variation in yield, N uptake and N use efficiency of medium and late<br />

duration rice varieties. Journal of Agricultural Science 144, 69-83.<br />

Teherani, D.K. (1987). Trace elements analysis in rice. Journal of<br />

Radioanalytical and Nuclear Chemistry 117 (3).<br />

Thöni L,. Seitler E. & Matthaei D. (2007) Ammoniak-Immissionsmessungen in<br />

der Schweiz 2000 bis 2006, im Auftrag des Bundesamtes für Umwelt BAFU, der<br />

OSTLUFT un der Kantone Luzern und Freiburg, available at:<br />

http://www.bafu.admin.ch/luft/00649/01960/index.html?lang=de.<br />

USDA (1999) Soil Taxonomy. A Basic System of Soil Classification for Making<br />

and Interpreting Soil Surveys. Agriculture Handbook. Number 436, United<br />

States Department of Agriculture – Natural Resources Conservation Service.<br />

USDA (2004) Brazil soybean area map. United States Department of Agriculture<br />

– Foreign Agricultural Service, online. Availble at:<br />

http://www.fas.usda.gov/pecad2/highlights/2004/03/crop_watch/w040326/.<br />

USDA 2004b USDA (2004) Brazil: Soybean expansion expected to continue in 2004/05.<br />

Production Estimates and Crop Assessment Division. August 2004.<br />

USDA 2004c<br />

USDA 2009<br />

von Steiger & Baccini 1990<br />

Walther et al. 2001<br />

USDA (2004): Malaysia: Below-Normal Rainfall May Limit Palm Oil Yields<br />

Late 2004-Early 2005. United States Department of Agriculture - Production<br />

Estimates and Crop Assessment Division. Foreign Agricultural Service.<br />

USDA (2009) Census of Agriculture 2007. United States Department of<br />

Agriculture – National Agricultural Statistical Service, online. Available at:<br />

http://www.agcensus.usda.gov/Publications/2007/index.asp.<br />

von Steiger B. & Baccini P. (1990) Regionale Stoffbilanzierung von<br />

landwirtschaftlichen Böden mit messbarem Ein- und Austrag. Nationales<br />

Forschungsprogramm 22, Boden.<br />

Walther U., Ryser J.-P. & Flisch R, 2001. Grundlagen für die Düngung im<br />

Acker- und Futterbau 2001. Agrarforschung, 8 (6): 1-80. Command at<br />

http://www.art.admin.ch/dokumentation/.<br />

33


<strong>Direct</strong> <strong>field</strong> <strong>emissions</strong> and elementary flows in LCIs of agricultural production systems - Literature<br />

Wilke & Schaub 1996<br />

Wilke B. & Schaub D. (1996) Phosphatanreicherung bei Bodenerosion. Mitt.<br />

Deutsche Bodenkundl. Gesellsch. 79, 435-438.<br />

Wolfensberger & Dinkel 1997 Wolfensberger U. & Dinkel F. (1997) Beurteilung nachwachsender Rohstoffe in<br />

der Schweiz in den Jahren 1993-1996, FAT und Carbotech, im Auftrag des<br />

Bundesamtes für Landwirtschaft, Bern.<br />

Zhao 2008<br />

Zhao L. (2008) Life cycle assessment on biofuel derived from sweet sorghum<br />

(presentation). International Conference on Sorghum for Biofuel, August 20,<br />

2008, Houston, TX, USA. Available at:<br />

http://www.ars.usda.gov/meetings/Sorghum/presentations/Zhao.<strong>pdf</strong>.<br />

34

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