摘要:Mountain regions cover 20% of terrestrial land surfaces
and represent one of the principle source regions for the
world's hydrological Systems. Mountain regions are today under pressure as a result of human interference;
climatic change could lead to an additional stress on
natural and socio-economic Systems.
Paleo-climatic evidence has shown that past climatic
change has lead to substantial shifts in the distribution
of Vegetation. If the present warming trend were to continue into the 21" Century, there would be significant
impacts on ecosystems. In particular. certain species
may become extinct because ot their limited capacity
for migration to regions with favorable climatic and soil
conditions.
In most mountain regions, a warmer climate will lead to
a reduction in the mass of glaciers, as well as snow-pack
and permafrost. Changes in precipitation regimes may
have far-reaching consequences for fresh-water supply
to agriculture, tourism and hydro-power. These shifts
would affect not only mountain populations, but also
those living downstream from the mountains and who
depend on mountain-fed water resources.
The social structure of populations in the mountains of
the developing world may be disrupted by environmental change, because of the impacts this change is likely
to have on the natural resources essential to traditional
lifestyles of mountain communities.