Spatial Distribution, Morphological Characteristics, and Socioeconomic Impacts of Gullies in Gombi Local Government Area, Adamawa State, Nigeria

Abstract

Gully erosion is a significant environmental and developmental challenge in Nigeria, contributing to severe land degradation, loss of agricultural land, and threats to infrastructure and rural livelihoods. This study investigates the spatial distribution, morphological characteristics, and socioeconomic impacts of gullies in Gombi Local Government Area (LGA), Adamawa State. Field survey was conducted across 27 randomly selected gully sites. GPS, leveling staff, and measuring tapes were used to obtain precise coordinates and morphological dimensions, including gully length, mean widths, and mean depths. GIS-based spatial analysis was employed to assess the correlation between gullies, slope, and drainage patterns. Results revealed gully lengths ranging from 26–250 m (mean = 88 m), widths from 2–12.2 m (mean = 4 m), and depths from 0.7–5.1 m (mean = 1.5 m), classifying most gullies as medium in size. Gullies were unevenly distributed, with hotspots in the eastern, north-central, and western parts of the LGA, highlighting areas highly susceptible to erosion. Communities reported increasing gully expansion and recognized the destruction of farmlands, roads, bridges, and river channels. These findings indicate that hydrological connectivity, slope, and human land-use activities are key drivers of gully formation and growth. The study provides baseline data for targeted interventions, including slope stabilization, afforestation, engineering controls, and policy implementation to mitigate erosion and safeguard socioeconomic development.