Impact of Land Degradation on Physical Properties of Soils in Mokwa Local Government Area, Niger State, Nigeria

Knowledge of soil physical properties is often employed for assessment and monitoring soil degradation. For effective and sustainable land conservation management, inventory and mapping of the soil physical properties, such as texture, bulk density, total porosity and saturated hydraulic conductivity (Ksat) are very important. This study therefore, assessed and mapped the levels of soil degradation across four land-use types (LUTs) designated as built-up (BA), forest cover (FC), cultivated land (CL) and fallow lands (FL) in 11 districts under Mokwa Local Government Area (LGA) of Niger State, Nigeria. In each LUT, surface soil samples were collected at 0-15 cm depth along diagonal transects. Particle size distribution, bulk density, total porosity and Ksat were determined using standard laboratory procedures. Results revealed predominantly sandy loam texture, high soil bulk density in BA, 1.60 g kg-1, FC, 1.57 g kg-1, CL, 1.61 g kg-1 and FL, 1.46 g kg-1. Total porosity was low to moderate: 33-48%, 31-43%, 31-41% and 31-48% in BA, FC, CL and FL and mean Ksat values were 0.54, 0.50, 0.59and 0.57 cm hr-1 for BA, FC, CL and FL respectively, and were classified as slow to moderate. Aggregate scores for soil degradation were 64% for BA and FC, 57% and 53% for CL and FL respectively which inferred moderate degradation across all LUTs. These findings underscore the role of land use in soil degradation and highlight the importance of conservation practices. Long-term monitoring, conservation agriculture, agroforestry, and integrated nutrient management are recommended to restore soil quality.