Abstracts available here - Society for Conservation Biology

25th International Congress for Conservation Biology • Auckland, New Zealand • 5-9 December 2011
2011-12-08 10:30 Climate change, Variability and conservation
impacts in Australia
Prowse, TAA, University of Adelaide; Brook, BW*, University of
Adelaide;
Australian conservation scientists, managers and decision makers must
come to grips with anthropogenic climate change, imposed upon an already
variable regional climate system. Pre- and post-instrumental records and
climate proxies indicate that Australia has experienced wet and dry cycles
over intra-decadal to millennial time scales. Precipitation variation across
Australia is correlated with different climate features but reliable tools for
seasonal rainfall prediction are still some years away. Atmosphere-Ocean
General Circulation Models predict a widening of the Hadley circulation
and strengthening of the Southern Annular Mode, which should result in
reduced cool season rainfall over southern Australia. Shifts in the Australian
climate over the Holocene epoch, most notably increased ENSO variability
after 5 000 years ago, are associated with substantial vegetation change and
indicate the speed at which ecosystems may be altered. The CO2 fertilization
of plant biomes may mitigate increasing aridity to some extent but, in
general, climate change is expected to negatively affect native vegetation
and agricultural productivity. Sea-level rise is predicted to be substantial
over this century and, when coupled with increased storm intensity, poses
threats in the form of erosion, salinization and flooding. The best chance
of building adaptable ecosystems and preserving ecosystem services requires
the extension, integration and possibly optimization of reserve systems, in
concert with improved management of other threatening processes (habitat
loss, invasive species, overexploitation, pollution and disease). In addition,
a price on carbon dioxide emissions would provide incentives for privately
funded reforestation schemes, but additional incentives promoting mixed
species over monoculture plantings would be required to assure maximum
biodiversity benefits.
2011-12-09 11:00 Conservation Management of Complex Edge Effects
Pryke, J. S.*, Stellenbosch University; Samways, M.J., Stellenbosch
University;
Understanding edge effects between transformed landscapes and
conservation areas is critical to conservation planning. As conservation
areas in landscape mosaics are often composed of linear corridors, there
are more edges than would occur naturally. To determine minimum
width of corridors, we would first need to determine the extent of edge
effects. Plantation forestry has transformed much of the South African
grasslands, with ecological networks (ENs) currently being used to mitigate
this biodiversity loss and to maintain ecosystem processes. We compare
arthropod biodiversity along transects that ran from within plantation
blocks or indigenous forest patches (as a natural reference) into indigenous
grassland corridors. Two types of exotic commercial trees and various tree
age classes were studied. We found a 32 m edge zone from plantation blocks
into grassland corridors. Few significant edge effects from plantation blocks
occurred at greater distances than this, suggesting that grassland corridors
with a width