Dynamics of microbial population in the soil during bioremediation

Abstract

In the presence of pesticides in the soil, there is a tendency for the predominance of only a few functional groups of microorganisms, thereby affecting not only the general structure of the community, but also different biological processes in the soil. The research presented in this article aims to monitor groups of microorganisms during the bioremediation of soil long-term and complex contaminated with persistent organic pollutants (POPs). The experimental scheme for bioremediation of soil polluted with POPs involves the alternation of anoxic-oxic conditions and the addition of a fertilizer in different concentrations. The microbiological analysis of the polluted soil before bioremediation revealed the predominance of three functional groups of microorganisms: bacteria that assimilate mineral nitrogen, oligonitrophilic bacteria and ammonifying bacteria. Small amounts of micromycetes and Azotobacter and total lack of actinomycetes in the polluted soil were determined. In the experimental variants with added fertilizer, after five cycles of bioremediation, the microbial biomass increased significantly (by 15 and 155 times), and the degradation of pesticides was more intense.