Exploring Land use and Land cover change in themining areas of Wa East District, Ghana usingSatellite Imagery

Abstract

Abstract Satellite imagery has been widely used to monitorthe extent of environmental change in both mine andpost mine areas. This study uses Remote sensing and GeographicalInformation System techniques for the assessmentof land use/land cover dynamics of mine relatedareas in Wa East District of Ghana. Landsat satellite imageriesof three different time periods, i.e., 1991, 2000 and2014 were used to quantify the land use/cover changes inthe area. Supervised Classification using Maximum LikelihoodTechnique in ERDAS was utilized. The images werecategorized into five different classes: Open Savannah,Closed Savannah, Bare Areas, Settlement and Water. Imagedifferencing method of change detection was used toinvestigate the changes. Normalized Differential VegetativeIndex valueswere used to correlate the state of healthyvegetation. The image differencing showed a positive correlationto the changes in the Land use and Land coverclasses. NDVI values reduced from 0.48 to 0.11. The landuse change matrix also showed conversion of savannahareas into bare ground and settlement. Open and closesavannah reduced from 50.80% to 36.5% and 27.80% to22.67% respectively whiles bare land and settlement increased.Overall accuracy of classified 2014 image andkappa statistics was 83.20% and 0.761 respectively. Thestudy revealed the declining nature of the vegetation andthe significance of using satellite imagery. A higher resolutionsatellite Imagery is however needed to satisfactorilydelineate mine areas from other bare areas in such Savannahzones.