Spatiotemporal Analysis of Vegetation in Ideato North, Imo State (2005-2025) Using Remote Sensing Techniques

Abstract

Vegetation degradation remains one of the most pressing environmental challenges in tropical rural-peri-urban landscapes, where rapid land transformation often occurs without systematic monitoring. This study investigates the spatiotemporal dynamics of vegetation change in Ideato North Local Government Area, Imo State, Nigeria, between 2005 and 2025 using multi-temporal Landsat imagery and the Normalized Difference Vegetation Index (NDVI). Satellite data for 2005 and 2025 were preprocessed through radiometric, atmospheric, and geometric corrections before NDVI computation. The resulting NDVI maps were reclassified into vegetation health categories and subjected to change detection analysis to quantify spatial transitions over the 20-year period. Findings reveal a substantial 29% decline in dense and healthy vegetation, accompanied by a 15% increase in sparse or stressed vegetation and a 14% expansion of open/bare land. Urban land increased modestly by 1%, reflecting gradual peri-urban growth. Spatial analysis further indicates pronounced fragmentation of previously contiguous vegetation blocks, suggesting declining ecological integrity and increased landscape vulnerability. These changes are strongly associated with anthropogenic pressures, particularly agricultural expansion, settlement growth, and land clearing practices. The results underscore a significant shift in ecosystem structure and productivity within Ideato North, with implications for soil stability, biodiversity conservation, carbon sequestration, and local climate regulation. By integrating remote sensing and GIS techniques, this study provides an evidence-based framework for long-term vegetation monitoring and sustainable land-use planning. The findings highlight the urgent need for targeted conservation policies, afforestation initiatives, and community-driven land management strategies to mitigate further environmental degradation and enhance ecological resilience in southeastern Nigeria.