174 The impactsof climate change
Figure 7.13Simulated environmental realised niches (the realised niche
describes the conditions under which the species is actually found) for three tree
species, Arolla Pine, Norway Spruce and Common Beech. Plots are of biomass
generated per year against annual means of temperature (T) and precipitation
(P). Arolla Pine is a species with a particularly narrow niche. The narrower the
niche, the greater the potential sensitivity to climate change.by the effects of pollution fail to cope with climate stress when it comes.
The assessment of the impact of climate change carried out for the MINK
region of the United States (see box on page 160) concluded that, under
the warmer, drier conditions of the analogue climate they studied, decline
and die-back of the forested part of the region would reduce the mass of
timber in the forest by ten per cent over twenty years.^49 The results of