Assessment of Soil Quality in Soils of Contrasting Geological Formations in Anambra State, Nigeria

Soil quality deterioration is one of the major limitations of agricultural production in Anambra State. This study assessed soil characteristics and quality across four geological formations: Ameki (AM), Alluvial Plain (AP), Ogwashi-Asaba (OA), and Imo Shale (IS). Soil samples were collected in triplicate from each geology at three depths (0-30, 30-60 and 60-90 cm), giving a total of 72 samples (36 core and 36 bulk). Standard laboratory methods were used for soil analyses, while data were subjected to analysis of variance. Soil texture varied from Sandy loam (AP) to loamy sand (AM and OA) and clay loam (IS). The trend in soil quality indicators was AP>IS>AM >OA, whereas the soil quality index ranged from 28 to 39%, with AP falling into moderate class while others qualified as low class. The major limitations to soil quality in most of the geological formations were low C, N, av. P, K+, soil respiration, and high bulk density. Hence, this study show that geological formation influenced soil characteristics, and is one of the major determinants of soil quality.