COMPOSITION AND QUANTITATIVE INDICATORS OF MICROFLORA IN IRRIGATED MEADOW-ALLUVIAL SOILS OF BUKHARA DISTRICT

Abstract

This article analyzes the composition, distribution patterns, and quantitative indicators of microflora in irrigated meadow-alluvial soils of Bukhara district. Soil samples were collected from the 0–5, 5–15, 15–30, 30–50, and 50–70 cm layers and studied using classical microbiological methods on meat-peptone agar, Ashby, Hutchinson, Czapek, and starch-ammonia agar nutrient media. The results showed that total microflora, including rod-shaped bacteria and actinomycetes, was more abundant on meat-peptone agar, whereas nitrogen-fixing microorganisms similar to Azotobacter were detected on Ashby medium. In general, the upper soil horizons were characterized by higher microbial abundance and greater morphological diversity of colonies. However, a local maximum recorded in the 30–50 cm layer of profile R-3 indicates the heterogeneity of microbial activity within the soil profile. During the summer period, the activity of cellulose-decomposing microorganisms and filamentous fungi increased, confirming the existence of seasonal microbiological dynamics. The obtained data can be used to assess the biological activity, fertility level, and reclamation status of irrigated soils.