The threat of climate and land use change against biodiversity

Researchers from Aarhus University, Denmark, and the
University of Wisconsin-Madison, USA, have developed a
new approach to measure the combined exposure of
species to both climate and land use change. This new
metric was used to assess the risk to species in the face of
combined rates of climate and land use for the US from
2001 to 2051.
Their results, which have just been published in Nature
Climate Change , highlight areas expected to be most
vulnerable to losses in biodiversity and ecosystem function
due to the individual or combined effects of climate and land
use change predicted by the mid-21st century. Exposure
was highest in the Great Plains and Northeast U.S.,
suggesting that these areas will be particularly at risk to the
combined effects of climate and land use change.
Furthermore, the paper reports that climate is changing at a
greater rate than land use change in most regions of the US
and that the joint rates of climate and land use change are
low across much of the interior west.
Different strategies for conservation and management
"By assessing climate and land use changes
simultaneously, we found a substantially greater estimate of
species exposure to global change threats than either land
use or climate change alone," explains Alejandro Ordonez
from Department of Bioscience, Aarhus University. "For
example, in areas where climate and land use change will
be slower, species may be able to persist in place and adapt
to the changes, or move into new suitable habitats. In
contrast, the areas where climate change and land use
change are accelerating will create the greatest threats to
ecological communities, and ecosystems may not be able to
keep up." Ordonez adds: "It would seem intuitive that such
a combined map would have been done before, but this is
the first time that we have been able to map this combined
risk in to the future thanks to the socio-economic land use
projections generated by two of the authors".
By integrating both future climate change and intensifying
land use threats, the authors indicate that a different set of
conservation priorities emerge than if one considers risk
from climate change alone.
"We know that the impacts of both climate change and land
use change will be highly localized, which means that
management and adaptation-planning strategies must be
flexible to account for the interactions of both. In our study,
we use two regions to highlight how a set of broad-scale
management strategies and interventions that can be useful
for conservation decision-making, and to assess where and
which adaptation efforts are most likely to be successful
under unique combinations of risks due to climate and land
use change," says Ordonez.
For example, within the U.S., regions exposed to both high
rates of climate change and reductions in forest or
rangelands may be priorities for land acquisition and
protection efforts. However, potential reserve areas should
be carefully evaluated in the context of urbanization given
limited conservation resources, as this may require
substantial investments for land acquisition.