Land Use Land Cover Change and its Effects on Ecosystem Service values in Gelana Watershed, West Guji Zone, Oromia, Ethiopia

Abstract

Land use land cover (LULC) transformation and ecosystems service valuation (ESVs) play important roles for vegetation restoration and design restoration options such as payment for ecosystems service programs. The objective of this study was to evaluate the impacts of land-use and land cover changes impacts on ecosystem service values of the Gelana watershed. Satellite Images were taken from Landsat 5 TM for 1992 and 2007, and Landsat 8 OLI_TIRS and classified by supervised classification technique with a Maximum Likelihood Algorithm (MLA) in ERDAS Imagine 2015. The study estimated the effects of LULC changes on ESVs using the modified ecosystem service value coefficients. ESVs for different land use types were assessed using the benefit transfer method. The summarized LULC classes include Bareland, Built Up, Cropland, Grassland, Mixed Forest, Shrubland, Water Body and Wetland. In 1992, mixed forests had the highest coverage (> 172,937 ha or approximately 50.2%), but by 2022, this had decreased to 120,992 ha (around 35.12%). Over 38,000 ha of forests were converted to cultivated land, and more than 13,945 ha underwent other changes. Crop land increased to over 104,277 ha (about 30.27%) in 2022 compared to 53,528 ha (approximately 15.5%) in 1992. The ESVs in the watershed amounted to US$344.06 mill in 1992 but declined to US$250.52mill in 2022, resulting in a loss of approximately US$93.54 mill over the past 30 years (equivalent to an annual loss rate of US$3.12 million). These findings emphasize the need for coordinated efforts to restore and manage landscapes for sustainable socio-ecological and economic purposes. Therefore, it is highly recommended that implementing sustainable watershed management practices to halt the dramatic loss of natural ecosystems must be a high priority