Evaluation of Soil Erosion Hazard in Hillside Farmlands of Imo State, South East Nigeria

This study evaluates the soil erosion hazard on hillside farmlands in Imo State, located in Nigeria's South East geopolitical zone, where gully and sheet erosion are severe constraints on agricultural productivity and land degradation is accelerating due to population pressure and forest clearing. Using a descriptive field assessment design, ten representative hillside farm plots were selected across three local government areas with varying slope gradients and land use histories. Morphological soil profile descriptions, bulk density measurements, texture analysis, and organic matter determination were conducted on each plot. Erosion indicators including rill density, gully presence, exposed subsoil, and surface crusting were scored using a standardised field rating scale. Runoff potential was estimated using the curve number method based on observed land cover and soil texture. Findings revealed that slopes exceeding 8 percent showed severe sheet erosion risk, with soils displaying low organic matter below 0.8 percent, high silt and fine sand content, and reduced aggregate stability. Bare soil exposure following vegetation clearing was identified as the most critical immediate erosion driver. The study found that traditional mound tillage on slopes without contour alignment significantly increases erosion risk. Recommendations include the adoption of contour ridging, grass-strip intercropping, and live mulching techniques as cost-effective erosion management measures for Imo State hillside farmers, alongside community-based gully rehabilitation. Keywords: soil erosion, hillside farmlands, Imo State, gully erosion, land degradation.