Spatial Temporal Dynamics of Hydrological Systems in Part of River Benue Makurdi, Benue State: A GIS Analysis of Critical Environmental Resource Management in Makurdi, Nigeria

Abstract

This study explores the complex dynamics of land use and land cover (LULC) transformations along and within the River Benue in Makurdi, Nigeria, with particular focus on seasonal variations of water resources and alluvial deposits. Using advanced remote sensing and Geographic Information System (GIS) technologies, multi-temporal Landsat satellite imagery from 1976 to 2024 was analyzed to assess environmental changes and their implications for sustainable resource management. The research employed a 6 km buffer zone along the River Benue, utilizing QGIS, ArcGIS, ERDAS Imagine, and Terrset 2020 for supervised classification and change detection analyses. Five distinct land cover classes were identified: Built-Up, Farmland, Water Body, Vegetation, and Alluvial Deposits. Key findings revealed significant transformations over the 48-year period. Water bodies declined drastically during dry seasons, shrinking from 79.19 km² in 1976 to 42.43 km² in 2024. Conversely, alluvial deposits exhibited consistent growth from 18.03 km² to 54.98 km², reflecting changes in sedimentation patterns. Urbanization was a pronounced driver of LULC changes, with built-up areas expanding dramatically from 13.23 km² to 94.03 km², coinciding with vegetation decline from 412.28 km² to 262.90 km². Seasonal variations highlighted the basin's dynamic nature, with wet seasons showing significant water body expansions (304.85 km² in 2012 and 236.61 km² in 2022) attributed to dam releases and precipitation. Predictive modelling projected continuing reductions in vegetation and water bodies coupled with increases in built-up and agricultural areas unless targeted conservation efforts are implemented.