ANALYSIS OF MORPHOMETRIC PROPERTIES FOR PRIORITIZATION OF SUBWATERSHEDS FOR EROSION CONTROL IN MAGARYA CATCHMENT, GOMBE METROPOLIS, GOMBE STATE, NIGERIA.

Abstract

This study focuses on the prioritization of erosion-prone sub-watersheds within the Magarya
Catchment, Gombe Metropolis, Nigeria, utilizing morphometric analysis. Advanced remote
sensing data, specifically the 30m resolution DEM from the Shuttle Radar Topography Mission
(SRTM), was employed to create drainage networks and delineate sub-watersheds using ArcGIS
software. Six distinct sub-watersheds (SW1–SW6) were identified and assessed based on various
morphometric parameters, including linear, relief, and areal characteristics. Twelve
morphometric parameters were selected to rank and prioritize these sub-watersheds. The study
reveals notable findings, such as: The dominance of dendritic drainage patterns in the basin,
indicative of homogeneous texture and impermeable geological features. SW-4 and SW-5
identified as fifth-order streams, suggesting higher volume stream flow compared to others. The
total number of streams ranging from 12 (SW-6) to 89 (SW-5), indicating lithological diversity
among sub-watersheds. The longest total stream length of 62.5 km observed in SW-2. SW-6
exhibits the lowest drainage density at 2.63 km/km2, suggesting permeable materials and high
infiltration rates. SW3 categorized as having a high susceptibility to soil erosion, covering 28.91%
of the total study area. This study did not assess the Cross-profile of the river, it recommends
further investigations in this regard. Additionally, the study suggests implementing soil
conservation practices such as bunds, check dams, micro-basins, and planting past growing plants
species in strategic locations based on suitable design parameters.