Soil nutrient availability and interrelationships in paddy-cultivated alfisols of Northern Telangana

The Northern Telangana (NT) Zone is a major rice-growing region experiencing imbalanced fertilizer use, declining soil organic carbon, and emerging micronutrient deficiencies; however, comprehensive information on nutrient availability and interrelationships in paddy-cultivated alfisols remains limited. To address this gap, the present study evaluated the physico-chemical properties, nutrient status, and interrelationships among soil parameters in paddy-cultivated alfisols of the region. A total of 45 surface soil samples (0–15 cm) were collected from representative mandals using a stratified random sampling design based on soil type and land use. The samples were analyzed for pH, electrical conductivity (EC), organic carbon (OC), available nitrogen (N), phosphorus (P₂O₅), potassium (K₂O), iron (Fe), and zinc (Zn). The soils were neutral to slightly alkaline (mean pH 7.26) and non-saline in nature. Organic carbon content was low to medium, while available nitrogen was generally low to medium. Phosphorus and potassium ranged from medium to high. Iron was adequate in most samples, whereas zinc showed high spatial variability, indicating potential deficiency in certain locations. Correlation analysis revealed mostly weak-to-moderate relationships among soil properties, with a positive association between available nitrogen and phosphorus and a negative relationship between zinc and soil pH and potassium. The results emphasize that it is necessary to implement site-specific nutrient management, particularly for organic carbon improvement and zinc supplementation, to sustain rice productivity in the region.