The biomass of microorganisms in soils of the transbaikal region

The population and biomass of the main groups of microorganisms (fungi, bac teria, and actinomycetes) and their distribution in the soil profiles were studied in Buryatia. The largest populations of microorganisms were found i n the upper humus horizons of all soils. All studied soils differ by microb ial biomass, proportions of different groups, and their distribution in the soil profile. The microbial mass in soils of Buryatia rs significantly low er (three times or more) as compared with microbial biomass in analogous Eu ropean soils. However, its structure is relatively stable irrespective of t he geographical position. The biomass of eucaryotic microorganisms exceeds that of the procaryotic ones, and mycelium dominates in the structure of th e eucaryotic complex, Agricultural development of soils results in the incr ease of the share of fungal spores in the structure of eucaryotic organisms . Bacteria (and spores of actinomycetes) dominate in the structure of the p rocaryotic complex. The share of actinomycetes mycelium is small and ranges from a fraction of 1% to 1-2%.