Impacts of urban land use and land cover change on wetland dynamics in Jimma city, southwestern Ethiopia

Abstract

Wetland was substantially decreased by anthropogenic activities worldwide, which needs argent conservation action. The present study aimed to analyze the effects of land use land cover change on wetland dynamics from 1992 to 2022 in Jimma City, Southwestern Ethiopia. Landsat TM of 1992, ETM+ of 2000, ETM+ of 2009 and OLI/TIRS of 2022 were used. ArcGIS 10.3 and ERDAS Imagine 2015 were used in the study. Landsat images were classified by using supervised classification with maximum likelihood algorithm. The results revealed that grassland, wetland and vegetation land cover classes were declined by 2,304.9 ha, 1410.2 ha and 820.5 ha, respectively whereas, farm land, settlement and bare land were increased by 2,199 ha, 2,111 ha and 225.4 ha, respectively from 1992 to 2022. Results show that the normalized difference water index (NDWI) has positive and negative strong relationship with normailized difference vegetation index (NDVI) and normalized difference built up index (NDBI) with the Coefficent determination (R2) of 0.96 and 0.98, respectively. Due to rapid urbanization and declining of vegetation cover in the study area, about 98% of wetland land cover in the study area lost over the past decades. The governmental and non-governmental organization should give special attention to wetland restoration and management in the study area.