SUG‘ORILADIGAN TIPIK BO‘Z TUPROQLARNING GUMUS TARKIBI VA GUMUSLI HOLATIGA TURLI O‘G‘ITLASH ME’YORLARINI TA’SIRI

Abstract

The article presents the humus status of irrigated typical sierozem soils, its group and fractional composition, and the patterns of changes under long-term stationary experiments. The effects of different farming systems and fertilizer rates on soil humus were comparatively analyzed. In continuous alfalfa cultivation, labile fulvic acids dominated over humic acids, indicating reduced humus quality and accelerated mineralization. In treatments with annual application of 30 t/ha manure and alternating buckwheat–alfalfa cropping, the share of humic acids increased, promoting humus stabilization and soil fertility. The results confirm the importance of organic fertilizers and crop rotation in typical sierozems.