Spatio-temporal Modelling of Land-use/Landcover Dynamics in Owerri West, Imo State Using Geospatial Technique

Abstract

In recent times, the pressures from uncontrolled land use has resulted to several environmental problems including flooding, pollution, erosion etc. thereby posing a trait to environmental sustainability in Owerri west.  Therefore, this research evaluated Land-use and Landcover changes in Owerri west local LGA in Imo state using multi-dated satellite Imagery. The major aim of the study was to carry out analysis of land-use/land cover development trends, thereby detecting the changes that have taken place between the year 2000 to 2020. Software used include ERDAS Imagine, ArcGIS10.5 and Microsoft excel. Three Landsat images, 5(TM), 7 (ETM+) and 8 (OLI) images of 2000, 2010 and 2020were acquired, pre-processed and classified using supervised classification algorithm. Progressively, accuracy of the classified result and change detection analysis was performed to investigate the changes that has taken placebetween this period. The spatial and temporal analyses indicate that, all LULC classes altered from their initial state within these epochs. The result of the study shows that the built-up areas have been on a significant constant positive expansion covering 22.57% ,36.11% and50.30% of the study area in 2000, 2010 and 2020respectively. Forest decreased from 31.32% to 20.54% and finally to 13.03%.Sparse vegetation decreased from 23.86% to 23.35% and to 15.28%. Exposed surface decreased from 12.24% to 10.04% and increased to11.08%.Water body decreased gradually from9.99%, to 9.97% and 9,89%%. The study further predicted that beyond the year 2050 thick vegetation may vanish and replaced by urban expansion and this is of grave consequences to the eco-environment. Therefore, this study suggests the establishment of forest reserves and planting of trees within the study area.