Biogeochemical cycles and exposure assessment in tundra zones

BIOGEOCHEMICAL CYCLES AND EXPOSURE ASSESSMENT IN TUNDRA ZONES 

The tundra zone and corresponding tundra ecosystems occupy the northernmost strip of the continental area of Eurasia and North America bathed by the seas of the Arctic basin. The climate conditions of the tundra zone provide for a higher productivity of ecosystems and higher activity of biogeochemical cycles of various elements as compared with the Arctic ecosystems. The mosses, lichens, and herbaceous plant species are predominant in the northern part of the Tundra ecosystems and shrubs are prevalent in the southern part. 

The edaphic microflora is diversified, and the microbial community is more numerous than that of the arctic soils. The bacterial population varies from 0.5 x 106 to 3.5 x 106 specimens per gram in topsoil horizon. 

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