Evaluation of selected soil physicochemical properties for integrated soil fertility management in agricultural communities in Southern and Northern Nigeria

Soil health and fertility are vital for sustainable agriculture and food security in Nigeria. However, they are increasingly threatened by nutrient depletion, soil degradation, and unsustainable farming practices. This study evaluates soil physicochemical properties from farming communities in Nigeria's southern and northern regions to identify nutrient deficiencies and develop localized management strategies. Soil samples were collected from Ekiti, Ondo, Nasarawa, and Sokoto states, representing diverse climatic zones ranging from the tropical rainforest in the south to the Sahel savanna in the north. One hundred and eight (108) soil samples were analyzed for properties, including pH, organic carbon (OC), total nitrogen (TN), available phosphorus (AP), exchangeable cations, and texture. The results indicated marked spatial variation in soil properties. The southern soils were richer, with 2.44% OC and 0.29% TN, reflecting rich vegetation cover, whereas the northern soils were sandy, with high sand content and lower OC and TN, showing poor fertility. Higher pH and calcium are accompanied by low AP in the north, limiting their productivity. Hierarchical cluster analysis grouped the soil properties into five clusters, which separated fertility-related properties of OC, TN, and cation exchange capacity from textural components. This calls to adopt site-specific soil management practices that include organic amendments in the north and pH adjustments in the south to enhance nutrient availability and soil health. This further justifies the regional approach to solving Nigeria's soil fertility challenges, reducing the gap between technology and practice, and realizing sustainable agricultural productivity.