Microbiological Characteristics of Soils of the Upper Delta of the Selenga River under Arid Conditions (Baikal Region)

Abstract

The abundance, ratio of ecologo-trophic groups of microorganisms, microbial biomass, and predominant members of the taxonomic composition of microbial complexes are indicators of the different ecological states of soils of the central floodplain and islands of the upper delta of the Selenga River under arid conditions. The highest coefficients of oligotrophy with an increased share of microorganisms growing on the nitrogen-free Ashby medium, as well as predominance of Arthrobacter bacteria, were determined in low-moistened soils of the islands. In general, low microbiological activity (in comparison with the soils of the central floodplain depressions), resulting from a lack of moisture, is observed in these soils despite the uncontrolled cattle grazing in the areas of the latter.