Biogeochemical cycling of elements and pollutants exposure in Forest ecosystems

BIOGEOCHEMICAL CYCLING OF ELEMENTS AND POLLUTANTS EXPOSURE IN FOREST ECOSYSTEMS 

The plant species biomass of Boreal and Sub-Boreal Forest ecosystems accumulates a significant part of living matter of the whole planet. This value is about 700 x 106 tons of dry weight. The biomass per unit area of different Forest ecosystems varies from 100 to 300 ton/ha and even 400 ton/ha in the Eastern European Oak Forest ecosystems. The annual net primary productivity, NPP, varies from 4.5 to 9.0 ton/ha (Table 1). 

The microbial activity in forest soils is much more intense in comparison with Tundra ecosystems. Fungi, bacteria and actinomycetes play a significant role in degradation of carbohydrates of forest litterfall (Box 1). 

I MICROBIAL ACTIVITY N FIXATION NITRIF1CAYION DENITRIFICATION S INCORPORATION 

Microbial regulation in Forest ecosystems (after Nihlgard et al, 1994 Fenchel et al., 1998) 

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