Microbiocenosis of the Permafrost Soils of Transbaikalia under Agriculture Use

Abstract

An understanding of how the involvement of soils in agricultural turnover affects soil microbiocenosis has been attained. The aims of this study were to investigate the number of the main groups of microorganisms in microbial complexes, the carbon of microbial biomass and the enzymatic activity in permafrost soils under the influence of tillage. The presented data can provide an insight into the stability of the microbiome in region’s soils under agricultural influence. The significance of the study lies in obtaining new data on the microbiocenosis of permafrost soils, which will make it possible to reveal the orientation and intensity of microbiological processes during their agricultural use. The study uses the classical methods used in soil science and soil microbiology, which are characterized by accuracy and reliability. The general characteristics of the microbiocenosis of different types of the studied region’s soils have been revealed. The quantity of bacteria, including actinomycetes and fungi, in the studied soils was determined. The variability of indicators in time and space is shown. The number of bacteria was revealed to reach its maximum in the autumn period in grey forest non-podzolised soils, and the indicator decreases in the following manner: forest—10.6 billion cells/g, arable land—5.1 billion cells/g, virgin land—2.6 billion cells/g. The lowest indicator of bacterial abundance—0.5 billion cells/g was found on arable permafrost meadow chernozemic soil. A comparatively low bacterial content is characteristic of chernozem meal-carbonated: 1.9 billion cells/g on virgin land and 2.1 billion cells/g on arable land. The length of actinomycete mycelium is dynamic according to the seasons of the year. The maximum length of actinomycete mycelium was observed in grey forest non-podzolised soil (forest) in the autumn period—830 m/g. The maximum length of fungal mycelium was also observed in grey forest non-podzolised soil (forest) in autumn—1200 m/g. In arable variants, the length of fungal mycelium is high in grey forest non-podzolised soils and meadow permafrost soils. In chernozems and permafrost meadow chernozemic soils (virgin and arable) the index is much lower. Assessment of catalase activity showed that the studied soils are poor or moderately enriched in this enzyme. Relatively high invertase activity was found in all variants.