Biological Activity of Soils in the North of the Novaya Zemlya Archipelago: Effect of the Largest Glacial Sheet in Russia

The vegetation cover and the chemical and physical properties of strongly skeletal residual-calcareous pelozems (Skeletic Leptosols (Loamic)), carbopetrozems (Calcaric Leptosols (Protic)), petrozems (Skeletic Leptosols (Protic)), and cryozems (Oxyaquic Cryosols (Loamic)) in the northern part of the Novaya Zemlya archipelago are described. The reserves and structure of microbial biomass, the intensity of CO2 (basal and substrate-induced respiration), CH4 (methanogenesis), and N2O (denitrification) emissions in the soil samples have been determined. The biomass of microorganisms (prokaryotes and fungi in total) varies from 22.50 to 390.18 mu g/g soil. The share of mycobiota in the microbial biomass reaches 80-98%. Most of the microbial biomass (up to 50%) is concentrated in the surface horizons. The number of prokaryotes ranges from 1.5 x 10(7) to 9.66 x 10(8) cells/g soil, and the biomass of fungi varies from 22 to 372 mu g/g soil. The length of the actinomycete mycelium is small: from 0.6 to 23.5 m/g soil, and the length of fungal hyphae is an order of magnitude higher (up to 166 m/g soil). All parameters of the biological activity of the studied soils sharply decrease down the soil profiles being positively correlated with the contents of organic matter, carbon, and nitrogen. In general, the values of the studied indicators of the biological activity of soils in the north of Novaya Zemlya are lower than those in soils located 3 degrees-5 degrees to the north, on Franz Josef Land. This phenomenon is explained by the influence of the largest glacier in Russia on the soil and vegetation cover on the adjacent territory in the north of Novaya Zemlya.