ИСТИНА

For the first time, the method next generation sequencing (NGS) was used to study the taxonomic diversity and the structure of bacterial communities in soils of the oasis Larsemann Hills. Three samples differing in C, N, and H20 content and in the presence of moss algal growth were investigated. The irst sample was selected from a mineral subsurface horizon with a low organic matter content ( 0.14 % C and 0.03 % N ) and a field moisture content of 6 % . In this sample , bacteria of the phylums Actinobacteria ( 37 % ) , Proteobacteria ( 22 % ) , and Chlorofleri ( 10 % ) dominated . The second sample was selected lipper horizon and was characterized by the presence of algal biofilms and low content of organic matter ( 0.12 % C and 0.02 % N ) and moisture content of 7.5 % Here , the phyla of Proteobacteria ( 36 % ) , Actinobacteri ( 24 % ) , and Bacteroidetes ( 15 % ) dominated. The third sample was selected from the moss cover of Ceratodon purpure and by higher matter ( 0.41 % C and 0.05 % N ) and a moisture content of 7.2 % . Here , the majority of operational taxonomic units belonged to the phylums Bacteroidetes ( 44 % ) , Acidobacteria ( 25 % , and Proteobaeteria ( 12 % ) As was shown earlier, communities of Antarctic soils are surprisingly diverse Analysis of our results and previously published data allows concluding that the dominance of certain bacterial phyla depends both on the physicochemical factors (moisture and organie matter contents) and on biotope that has been developed (the presence of algae growth, formation of cyanobacterial mats). The work was supported by the grant of the Rusian Foundation for Basic Research No. 18-34-00658.