HUMUS STATUS AND AVAILABILITY OF MOBILE NUTRIENTS (NPK) IN THE SOILS OF SHAHRISABZ CITY
Abstract
The article assesses the humus status and availability of mobile nitrogen, phosphorus, and potassium in irrigated typical sierozems, meadow-sierozems, meadow, and meadow-saz soils of Shahrisabz City, Kashkadarya Region of the Republic of Uzbekistan. The results revealed significant spatial and vertical differentiation in humus and nutrient contents. Humus content ranged from 0.485 to 3.962%, N-NO₃ from 4 to 18 mg/kg, P₂O₅ from 3.12 to 50.28 mg/kg, and K₂O from 70 to 535 mg/kg. The present condition of the soils has been shaped by the combined effects of natural pedogenesis, agropedogenesis, urbanopedogenesis, and biopedogenesis. The findings provide a scientific basis for assessing soil fertility and developing sustainable approaches to the management and conservation of urban soils.References
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