Spatiotemporal Assessment of Shoreline Changes in Ilaje Local Government Area, Ondo State, Nigeria

Abstract

The world we live in is dynamic, constantly changing and evolving, and changes, both natural and anthropological, have profound impacts on our environment and ecosystems. The goal of this study is to present a spatiotemporal assessment of shoreline changes in Ilaje Local Government Area (LGA), Ondo State, Nigeria, utilising remote sensing and Geographic Information System (GIS) techniques. The primary objectives were to quantify the extent of shoreline changes and to predict future shoreline dynamics. By analysing Landsat 7, 8 and 9 satellite imagery from 2003 to 2023, significant transformations were observed. QGIS 3.32.1 was utilised in pre-processing the imageries, ArcGIS 10.8.2 was utilised for creating composite images and spatial analysis. Digital Shoreline Analysis System (DSAS) software was used in calculating Linear Regression Rate (LRR), as well as predicting the shoreline changes. The results indicate a substantial shoreline retreat, with erosion impacting over 85% of the transects analysed, leading to an average shoreline retreat of over 160 meters. Predictive models suggest that vulnerable areas could experience up to 400 meters of additional erosion by 2033. These findings provide critical insights into the spatiotemporal dynamics of shoreline changes, supporting the development of adaptive management strategies. Recommendations include shoreline stabilisation efforts and integrated land-use planning to mitigate the adverse impacts of ongoing and future shoreline changes on the local ecosystems and communities.