Molecular Biological Characteristics of Soil Microbiome in the Northern Part of the Novaya Zemlya Archipelago

Microbiomes of strongly skeletal residual calcareous pelozems (Skeletal Leptosols (Loamic)), carbopetrozems (Calcaric Leptosols (Protic)), petrozems (Skeletal Leptosols (Protic)), and cryozems (Oxyaquic Cryosols (Loamic)) in the north of Novaya Zemlya were studied by the methods of molecular biology. The number of copies of 16S rRNA genes was small and ranged from 2.30 × 107 to 1.63 × 109 gene copies/g soil for archaea and from 3.47 × 108 to 2.26 × 1011 gene copies/g soil for bacteria; the number of copies of ribosomal genes ITS rRNA of fungi varied from 8.87 × 106 to 7.56 × 109 gene copies/g soil. The content of copies of ribosomal genes of all groups of microorganisms sharply decreased down the soil profiles. Bacteria predominated among prokaryotes (up to 90%). The greatest abundance (20%) was manifested by the phyla Proteobacteria, Actinobacteria, and Acidobacteria; the abundances of Bacteroidetes, Firmicutes, Verrucomicrobia, Gemmatimonadetes, and Chloroflexi were about 1–10%. The Archaea domain represented mainly by the Ferroplasma genus (phylum Euryarchaeota), accounted for ≤4% of prokaryotes. The taxonomic diversity of prokaryotes increased down the soil profiles and reached maximum values in the suprapermafrost horizons, where the number of candidate phyla typical of marine ecosystems—Latescibacteria, Tectomicrobia, Parcubacteria, Saccaribacteria, Hydrogenedentes, Peregrinibacteria, Ignavibacteria, and Gracilibacteria—was high.