Land Degradation Risk Assessment of Selected Wetlands in Yewa North Local Government Area of Ogun State, Nigeria Using Geospatial Techniques

Abstract

Wetlands are among the most ecologically significant yet vulnerable ecosystems globally, providing critical services such as flood regulation, water purification, biodiversity support, and carbon sequestration. In Nigeria, rapid population growth, agricultural expansion and urban encroachment have intensified land degradation pressures on wetland ecosystems. This study assessed land degradation risk in selected wetlands of Yewa North Local Government Area of Ogun State, Nigeria using geospatial techniques including Geographic Information Systems (GIS) and Remote Sensing. Land use/land cover maps were produced from multi-temporal satellite imagery and analysed alongside soil physical and chemical data. Results revealed a progressive decline in wetland extent from 2000 to 2020, with conversion primarily to agricultural land and settlements. Geospatial analysis identified areas of high degradation risk characterized by soil compaction, salinization indicators and vegetation loss. The study provides empirical evidence for targeted intervention and conservation strategies to halt and reverse wetland degradation in the study area.