Geographical peculiarities of biogeochemical cycling and pollutant exposure

GEOGRAPHICAL PECULIARITIES OF BIOGEOCHEMICAL CYCLING AND POLLUTANT EXPOSURE 

In the Northern Hemisphere the area of arctic and tundra landscapes with plant species ecosystems is 3,756,000 km2. In the Southern Hemisphere similar landscapes are completely absent. Most of these landscapes occur in northern Eurasia (Russia, Fennoscandia), Greenland, Alaska, and Canada. 

The low precipitation and freezing water stage during 10-11 months per annum have led to the development of arid polar and tundra landscapes. The characteristic features of these landscapes are the alkaline soil reaction (pH 7.5-8.0) and even the occurrence of modern carbonate formations. 

In accordance with the local maximum of precipitation and the relative low winter temperatures, the most favorable climate conditions for biogeochemical processes and pollutant exposure are in the western part of Spitzbergen Island. Three types of landscapes with corresponding ecosystems are widespread (Dobrovolsky, 1994). 

On the wide shore terraces of fjords and on the slopes of hills and low mountains, the Arctic Tundra ecosystems occur. The mosses and lichens are predominant with 

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