THE CHANGE IN COMPOSITION OF MICROBIAL BIOMASS IN CULTIVATED SOILS

The character and intensity of anthropogenic impact considerably affec t the abundance, biomass, and distribution of microbes along the soil profile. Soil cultivation results in the overall reduction of microbia l biomass, initially of the fungal mycelium, which is evident from the data on the reduction of fungal species diversity in cultivated soil, By a number of microbiological parameters, garden soil differs greatl y from the arable soil and is similar to the forest one. Liming exerts the strongest depressing effect both on the total microbial and the f ungal mycelium content, The percentage of spore biomass and fungal myc elium biomass in the main components of the microbial community is muc h the same, Drastic shifts in the abundance and composition of soil mi crobes in cultivated soil attest to the disturbance of natural process es of productivity maintenance. The obtained data allow us to quantify the consequences of anthropogenic pressure on the soil microbial comm unity.