The Fall of the Water

Cumulative impacts of land use and climate change on biodiversity

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their original abundance when ecosystems were hardly impacted by people. The abundance of a species means the population size of number of individuals of spe- cies. This indicator is in accordance with the indicators agreed upon under the Convention of Biological Diver- sity (UNEP, 2004).

For wildlife and ecosystems, however, it is the cumu- lative impacts of numerous pressures that determine actual effect on the abundance of species, including, but not limited to, infrastructure development and associ- ated land use, forestry, agricultural practices, nitrogen pollution and climate change.

Ecosystem function most generally is closely related to its original species and their abundance. Given dose-

In this section biodiversity has been defined as the aver- age abundance of the original species compared with

Figure 16: Current and projected reduction in abundance of biodiversity, expressed as percent of original abundance of biodiversity given no human disturbance. The four scenarios depict the cumulative impacts of climate change, infrastructure development, land use, forestry and N-pollution. Notice that the projections are model outputs on very general datasets and should be used with caution for other than depicting trends.

2000

Abundances of species (% original)

0 - 20 % 20 - 40 40 - 60 60 - 80 80 - 100

SRES A1 2030

SRES A2 2030

SRES B1 2030

SRES B2 2030