"Assessing Land Use-Land Cover Changes and Their Impacts on Ecosystem Services in Kiltie Watershed, South Achefer District, North Gojjam Zone, Northwestern Ethiopia."

Abstract

"This study aims to assess the extent of land use/land cover changes and their impacts on ecosystem services, as well as the effectiveness of mitigation measures in the Kiltie watershed, North-Western Ethiopia." The detection of land use/land cover changes via remote sensing data, including their impacts and mitigation measure status, is crucial for the study of the environmental sustainability of various decision-making support systems. The information from land use/land cover change detection aids in lulc and socioeconomic conservation and sustainable development, particularly ecosystem resource management. This study focuses on identifying LULC changes, observing impacts, and viewing mitigation measures taken at the selected study site. Primary data from questionnaires and secondary remote sensing data from Landsat satellite images from USGS earth explorer were used. To determine the number of samples, the Yamane-1967 formula was used. Landsat images of thirty years at each ten years interval 1990, 2005 and 2020 images were used. ArcGIS10.8, Google Earth, and Quantum-GIS were used for analysis to identify the LULC changes as well as to cross-check the perceptions of the impacts and mitigate the LULC changes. For the socioeconomic data, qualitative and quantitative analysis methods were applied to evaluate three consecutive time series of five major land cover classes: forest, grazing, settlement farm and bushlands. Image preprocessing, processing, classification, and accuracy assessment were carefully conducted, and the image analysis output was validated via confusion matrices, and the kappa coefficient was used for cross-checking the outputs. Therefore, from the point validation, the 2020th image analysis result shows average user accuracies of 88%, producer accuracies of 79.02% and kappa coefficients of 83%. The output shows that the LULC change analysis is valid. Therefore, the study revealed significant increases in agricultural land and settlement areas of 18.45% and 119.35%, respectively, for the past 30 years, and the perceptions and impacts of LULC changes are significantly observed by the study site society. Additionally, the perceptions and efforts for mitigations are significantly valid, although efforts to achieve sustainability have not yet been made. Therefore, effective land management practices, integrated watershed management, and active community participation are essential to prevent undesirable LULC changes since the watershed is located inside Abay basine and Tana watershed which can bring siltation problem to the Ethiopian Renaissance dam (GERD).