Assessment of Soil Fertility Constraints by Developing Thematic Soil Fertility Maps in Kuppambadur RBK of Ramachandrapuram Mandal in Tirupati District, Andhra Pradesh, India

Abstract

Soil fertility assessment plays a crucial role in sustainable agricultural planning and resource management. The present study was conducted to evaluate the soil fertility status of Kuppambadur RBK located in Ramachandrapuram mandal of Tirupati district, Andhra Pradesh, India. A total of three hundred soil samples were collected and analysed for physicochemical and nutrient properties to determine the fertility constraints of the region. The results indicated that the soils ranged from slightly acidic to strongly alkaline (pH 6.1–8.8) and were nonsaline (<4 dS m⁻¹). Organic carbon content was found to be low to medium (0.03–0.56%). Among macronutrients, the soils were low in available nitrogen (63.00–208.00 kg ha⁻¹), low to high in available phosphorus (11.00–72.00 kg ha⁻¹) and medium to high in available potassium (181–354 kg ha⁻¹). With respect to micronutrients, manganese (0.09–26.30 mg kg⁻¹), iron (0.30–36.00 mg kg⁻¹), copper (0.05–3.68 mg kg⁻¹) and zinc (0.08–6.82 mg kg⁻¹) levels varied from deficient to sufficient across the samples. Based on the fertility indicators, soil fertility constraints were identified and used to develop thematic soil fertility maps for the study area. The findings provide a scientific basis for site-specific nutrient management strategies aimed at improving soil health and enhancing agricultural productivity.