Geospatial Assessment and Mapping of Degraded Areas in the Sudan Savannah of Nigeria Using GIS and Remote Sensing Techniques

Abstract

The Sudan Savannah Zone of Nigeria has experienced notable shifts in land productivity due to the combined impacts of anthropogenic activities and climatic factors. Identifying and mapping degraded areas is critical, particularly in this region characterized by rapid population growth and advancing desertification. This study employed MODIS satellite imagery to evaluate land degradation dynamics in Sokoto and Kebbi States within the Sudan Savannah Zone from 2001 to 2021, utilizing Normalized Difference Vegetation Index (NDVI) trend analysis and correlation methodologies. Findings revealed that 31.06% of the study area exhibited land degradation, while 23.41% demonstrated productivity enhancements. Spatial analysis highlighted an escalating trend of degradation in Kebbi State, in contrast to significant improvements observed in Sokoto State. Human activities, including overgrazing and unsustainable agricultural practices, emerged as predominant drivers of degradation, whereas land recovery initiatives and natural regeneration processes contributed to productivity gains. The results underscore the urgency of adopting integrated land-use planning strategies to harmonize food security objectives with environmental sustainability, thereby advancing Nigeria's efforts toward achieving land degradation neutrality.