The effect of biochar on the structure of the prokaryotic complex of microcosms of soils contaminated with oil products (podzol, sod-podzoic and gray forest) was studied using molecular biological methods (RT-PCR, metabarcoding) and fluorescent microscopy. The introduction of biochar to soil samples with oil products led to a significant increase (by an order of magnitude for podzol) in the biomass of prokaryotes compared to variants without it. Against the background of an increase in biomass, the diversity of the prokaryotic component when adding biochar to soils with OP (a month after application) remains lower than in the control uncontaminated samples due to the emergence of certain representatives of hydrocarbon-oxidizing bacteria as dominants. For each of the studied soils, the most resistant to oil pollution genera of bacteria were determined: in the podzoic, these were representatives of the Pseudomonadota Massilia and Paraburkholderia, for sod-podzoic soil – Ramilbacter solistiva and Masillia, for samples of gray forest – Streptomyces occupied 14% of all bacteria, Nocardioides, Galella, Bacillus. In contaminated samples (both with and without the addition of biochar) compared to the control, an increase in the content of functional genes responsible for the synthesis of catechol-2,3-dioxygenase (xyIE) is observed, marking the initial stage of hydrocarbon degradation. It was found that when biochar is added to OP-contaminated soils, by the 30th day of the experiment, the highest number of copies of the xyIE gene and the lowest content of residual OP are noted. The obtained results on the abundance, biomass, taxonomic diversity and biotechnological potential of the prokaryotic community of soils can be useful for developing effective strategies for bioremediation of oil-contaminated areas.
G. V. Uvarov (Wed,) studied this question.