THE INFLUENCE OF OIL POLLUTION ON THE DIVERSITY OF MICROBIAL COMMUNITIES IN THE SOILS OF DOSSOR FIELD

Abstract

The study of changes in the microbial community structure is essential for understanding ecological processes and the bioremediation of oil-contaminated soils. The research revealed significant differences in the number and taxonomic diversity of cultured microorganisms in soil collected from the Dossor deposit. Soil with a low level of contamination exhibited a higher count and diversity of cultivated microorganisms. The abundance of microorganisms in soils containing 3,990-4,158 mg oil kg⁻¹ was two orders of magnitude higher than in soils with 58,770-61,589 mg oil kg⁻¹. The investigation identified the predominant bacterial phyla as Proteobacteria (47.5%), Firmicutes (18.0%), Actinobacteria (18.9%), Bacteroidetes (12.5%), and other phyla (3.31%). Microorganisms from the genera Micrococcus, Arthrobacter, Mycobacterium, Achromobacter, Gordonia, Ochrobactrum, Microbacterium, Nocardia, Streptomyces, Rhodotorula, Trichosporon, Candida, and Aureobasidium were detected. The microbial diversity of cultivated forms is diminished in soil with elevated levels of contamination. The findings demonstrate that long-term oil contamination significantly impacts the soil, acting as a stressor that alters the structure of the microbial community.