RESTORATION OF SOIL MICROBIOLOGICAL ACTIVITY AFTER HERBICIDE STRESS

Abstract

This paper presents the results of a study of carbon sorbent from sewage sludge and sawdust (biochar) effect on the restoration of soil microbiome after herbicide treatment. At the genus level, 28 representatives were found in the original soil, 35.7% of which were aerobes. Of these, Gaiella and Methylotenera predominated. Of the anaerobic - most were Veillonella and Faecalibacterium. The proportion of microorganisms affected by the herbicide was 71.4%. 32% completely disappeared from the soil microbial community, 39.3% recovered after the introduction of biochar. There was a recovery almost to the original value of microorganisms of the genera Veillonella, Faecalibacterium, Gaiella, Ilumatobacter, Gemmatimonas. The number of Azotobacter increased by 7.3 times. In the soil subjected to herbicide treatment, the proportion of microorganisms exhibiting catalase activity decreases or completely disappears. Members of the genus Gaiella, known as catalase-positive bacteria, were absent in herbicide-treated soil. Their population resumed after soil treatment with biochar, . Intrasporangium, also being catalase positive, were reduced by more than 4 times under the action of the herbicide. Cleaning the soil with a biosorbent made it possible to restore their numbers by 56%. The introduction of biochar from sewage sludge and sawdust into the soil activated the soil microbiota. The assessment of α-diversity by the Shannon index showed a 1.5-fold decrease in the species diversity of the microbial community of the soil treated with the herbicide. Cleaning the soil with biochar restored the soil microbiome, with a Shannon index of 2.4.