Land Cover Change Dynamics and their Driving Forces in the Western Escarpment of the Rift Valley in the Gamo Zone, Southern Ethiopia: Implications for Biodiversity Conservation and Climate Change Mitigation

Abstract

Land use and land cover (LULC) changes are caused by natural and human alterations of the landscape that could largely affect forest biodiversity and the environment. This study aimed to analyze LULC change dynamics and their driving forces in the western escarpment of the Rift Valley of the Gamo Zone, Southern Ethiopia. Digital satellite images were downloaded from USGS and analyzed using ERDAS Imagine version 14 and Arc GIS 10.2 software. Supervised image classification was used to generate LULC classification, accuracy assessment, and Normalized Difference Vegetation Index (NDVI). Drivers of LULC change were identified and analyzed.  Four land classes were identified: forest, farmland, settlement, and water-wetlands. Settlement and farmlands increased by 8% and 6%, respectively within three successive periods (1999-2019). On the other hand, during the same period, forest and water-wetlands decreased in their aerial coverage by 9% and 5%, respectively. The overall accuracy of the study area was 92.86%, 94.22%, and 94.3%, with a kappa value of 0.902, 0.92, and 0.922, respectively. NDVI values ranged between 0.42 to 0.73. Agricultural expansion (31.4%), expansion of settlement (25.7%), and fuelwood collection and charcoal production (22.9%) were the main driving forces that affected the biodiversity of the vegetation in the study area. Integrated land use and a policy on the current situation are deemed necessary to protect biodiversity loss, forest degradation, and climate change.