Assessment of Soil Fertility and Nutrient Status in Agricultural Fields

Soil fertility is one of the major factors controlling agricultural productivity, crop quality, and the long-term sustainability of farming systems. Continuous cultivation, imbalanced fertilizer application, removal of crop residues, erosion, and inadequate organic matter management can result in depletion or accumulation of essential plant nutrients. The present study was designed to assess the fertility status and available nutrient levels of agricultural soils using selected physicochemical and chemical parameters. Representative surface soil samples were collected from agricultural fields at a depth of 0–15 cm and analyzed for soil pH, electrical conductivity (EC), organic carbon (OC), available nitrogen (N), phosphorus (P), and potassium (K). The illustrative results showed that soil pH ranged from 6.7 to 7.8, indicating predominantly neutral to slightly alkaline conditions. Electrical conductivity remained within a range generally suitable for agricultural production. Organic carbon varied from 0.42 to 0.71%, indicating low to medium organic matter status. Available nitrogen was comparatively low in several fields, while available phosphorus showed low to medium levels and available potassium ranged from medium to high. The overall nutrient status indicated that nitrogen was the most commonly limiting nutrient, whereas potassium was comparatively better maintained. The results emphasize the importance of regular soil testing, balanced fertilization, organic matter management, crop-residue incorporation, and site-specific nutrient application. Soil testing commonly uses organic carbon, alkaline KMnO₄-extractable nitrogen, Olsen phosphorus, and neutral ammonium acetate-extractable potassium as important indicators of soil fertility in Indian agricultural soils.