Microbiological research of the soddy-podzolic soils located in black taiga of the Salair Ridge

The authors of this study conducted research regarding the qualitative and quantitative composition of microorganisms in two soil profiles, pledged under different types of vegetation in the aspen-fir forest (section P1-C10) and in the forestless area under the tall grass (section P2-C10). Location included: Basin Mungai (Kemerovo Region, Industrial area). From the deeply bleached soddy-podzolic soils located under the black taiga of the Salair ridge and formed under different types of vegetation, there were extracted ammonifiers, utilizers of nitrogen-free organic compounds and oligonitrophilics. In sod-podzolic soil of aspen-fir forest there is a high number of microorganisms that destroy nitrogen-free organic matter, a slightly lower number of ammonificators and an even lower number of oligonitrophilics. The maximum number of organisms is observed in the forest litter and humus-accumulative horizon enriched with organic residues, with increase of depth the number of microorganisms reduces. The numbers of microorganisms in soil samples from the aspen-fir forest is much higher than from the non-forested land. Here are the most numerous destroyers of nitrogen-free organic compounds and processes of mineralization run more intensely, as it is evidenced by the coefficients of mineralization. The number of oligonitrophilic and aerobic nitrogen fixers in soils of two plots was not significantly different. In the soil located under tall vegetation, the number of the studied physiological groups of microorganisms is almost 10 times lower, the richest is the upper soil horizon, with the increase of depth the number microorganisms decreases and further remains at about the same level. The most numerous are ammonifiers. From the composition of microorganisms that destroy the nitrogen-free organic compounds there were extracted actinomycetes, among the microscopic fungi the most frequently are met representatives of the genera Penicillium, Mucor. In soil of aspen-fir forests there were also found fungi of the genera Trichoderma, Alternaria. Among ammonificators there were discovered microorganisms belonging to the genera: Bacillus, Sarcina, Pseudomonas, Flavobacterium, Micrococcus, Achromobacter. Most numerous among them were bacilli. There were different types of this kind, also form the soils of both plots there were extracted colonies of Bacillus mycoides, forming specific colonies resembling the shape of a snowflake on the beef-extract agar. Composition ammonificators in the studied two sections of soil differ significantly in number and distribution over the profile of the yellow-pigment bacteria. On the basis of information on the colony and cell morphology, types of cell clusters and its tinctorial properties among the yellow pigment-forming bacteria there were extracted the members of the genus Sarcina. Number of sarcins is higher in the soil of treeless area, and their distribution in the profile is relatively equal.

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