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The search for active cellulolytic consortia among soil microorganisms is of significant applied interest, but the dynamics of the formation of such communities remain insufficiently studied. To gain insight into the formation of an active cellulolytic community, the experiment was designed to examine the colonization of a sterile substrate (cellulose) by microorganisms from two soil types: sod-podzolic and chernozem. To achieve this, the substrate was placed in the soil and incubated for six months. To assess microbiome dynamics, the experiment employed sequencing of 16S rRNA gene fragment and ITS2 amplicon libraries at four time points. It was demonstrated that, from the second month of the experiment, the prokaryotic component of the communities reached a state of stability, with a community composition specific to each soil type. The results demonstrated no relationship between changes in community diversity and soil respiration. There also was no significant shift in the community diversity throughout the chronosequence. Furthermore, the taxonomic composition of the community shifted towards a decrease in the proportion of Pseudomonadota and an increase in representatives of the Bacteroidota, Bacillota, and Verrucomicrobiota phyla. The network analysis of the community demonstrated that, in contrast to sod-podzolic soil, chernozem is distinguished by a higher modularity, with the formation of taxon-specific groups of microorganisms at each stage of the chronoseries. These differences are attributed to the alterations in the eukaryotic component of the community, particularly in the prevalence of nematodes and predatory fungi, which in turn influenced the cellulolytic community. [ABSTRACT FROM AUTHOR]

Localization of agriculture with the aim of local food support has become a very urgent topic for Yamal region. The most fertile soils of this region are sandy textured anthropogenically affected soils. Microbiomes from disturbed soils of the Nadym region were studied using analysis of 16S rRNA metagenomic libraries. It was shown that plant cover is a driving force of microbiome composition. Forest soils covered with aeolian transfers from the quarry retaids a typical forest microbiome with the following dominant bacterial phyla: Proteobateria, Acidobacteria, Verrucomicrobia, Planctomycetes and Bacteroidetes. However, it contains significantly less Planctomycetes, which indicates greater aridity of the soil. The microbiomes of the overgrown quarries were strikingly differ from the soil microbiome and resemble those of arctic soils being dominated by Proteobacteria, Chloroflexi, Acidobacteria and Cyanobacteria. Absence of dense vegetation cover and availability of nutrients facilitated the formation of autotrophic microbial mats. The microbiome of the lower horizons of the quarry is characterised by Proteobacteria, Actinobacteria and Firmicutes. Presumably, most of the time these bacteria reside in a dormant state with short periods of activity due to nutrient uptake from the upper horizons.

Microbial activity plays a crucial role in the development and formation of soil properties. The active and abandoned agricultural soils in the Arctic zone represent a valuable resource that can play a crucial role in providing food security in the northern regions. The reuse of abandoned land for agriculture will reduce environmental risks in the context of a changing climate. Therefore, there is a need for monitoring studies to assess changes in soil parameters after long-term abandonment (taxonomic diversity, agrochemical and physico-chemical qualities). In the study, we evaluated the taxonomic diversity of the microbiome in abandoned (postagrogenic) and pristine soils of the Central part of the Yamal region. In the process of taxonomic analysis, more than 30 different bacterial and archaeal phyla were identified. The formation of a specific microbiome associated with anthropogenic influence in post-agrogenic sites has been shown. Most common types of soil microorganisms in samples collected from pristine and postagrogenic soils were Firmicutes (average 26.86%), Proteobacteria (average 23.41%), and Actinobacteria (average 15.45%). Firmicutes phylum was found mainly in the agrocenoses soils, Proteobacteria were mainly described in the mature tundra soils, Actinobacteria in humid conditions. An increase in diversity indices in postagrogenic soils was shown. [ABSTRACT FROM AUTHOR]

Fires have a strong effect on soil microbiome, and the mechanisms of soil restoration after fires are currently not well understood. This study describes the characteristics of microbial communities in the gray-humus soils of pine forests in the city of Togliatti after forest crown and surface fires. Geochemistry, soil respiration and microbial community structure via 16S rRNA gene sequencing were studied in different soil horizons. Both crown and surface fires resulted in the decrease in microbial diversity and shifts in taxonomic composition. For samples recovering from fires, there is a tendency to an increase in the proportion of representatives from phylum Actinobacteria and Firmicutes and a decrease in Verrumicrobia. An increase in the proportion of bacteria (Micrococcaceae) associated with the degradation of substances formed after combustion also has been shown. From our work it follows that the crown fire has a smaller effect on the soil microbiome than the surface fire, the largest changes in the microbiome structure were found in the intermediate horizon. At the same time, differences in the structure of the soil microbiome between horizons are intensified after exposure to the soil of a surface fire.Work is supported by RSF grant 17-16-01030 «Dynamics of soil biota in chronoseries of post-technogenic landscapes: analysis of soil-ecological efficiency of ecosystem restoration processes» [ABSTRACT FROM AUTHOR]