MOLECULAR BIOLOGICAL AND MICROBIOLOGICAL CHARACTERISATION OF MICROBIAL COMMUNITIES OF SOIL ECOSYSTEMS UNDERGOING OLIGOTROPHICATION FOR THE DEVELOPMENT OF WAYS TO MANAGE MICROBIAL COMMUNITIES BY THEIR TROPHICS

Indicators of the number and activity of the microbial community (MC) of the soil ecosystem (SE), which underwent eutrophication due to the annual application of mineral or organic substances from 2011 y. to 2019 y., and then from 2019 y. to 2024 y. after stopping the additions of substances the oligotrophication of SE have occurring. Comparative analysis of basal respiration (BR) and substrate-induced respiration (SIR) and determination of the number of ribosomal copies of genes of bacteria, archaea and micromycetes (quantitative PCR) in soil samples, and 2024 y. revealed significant differences in these indicators due to of the changes in the trophic status of the soil ecosystem (SE). The eutrophication of soil ecosystem as the result of the introduction of minerals substances led to a decrease in respiratory activity (Table 1.) (Fig. 1) and the number of ribosomal copies genes (Fig. 2), while the introduction of organic substances significantly increased these indicators. In general, the results of the oligotrophication process, the determined parameters as indicators the oligotrophication become close to those in the control soil variant. The methods used to assess the consequences of oligotrophication of SE showed their sensitivity, and the results obtained make it possible to assess the processes that occurred in the microbial community when the trophic status of SE changed. Overall, the approach may prove useful for the development of methods for managing soil microbial communities.