The Nexus between Land Use and Land Cover Change, Vegetation Density, and Land Surface Temperature: A Case Study of Lake Abaya Catchment in the Southern Main Ethiopian Rift

Land use and land cover change (LULCC) significantly alters ecosystem processes by reducing vegetation cover, intensifying land degradation, and modifying local climate conditions. This study examined the interplay between LULC dynamics, vegetation density, and land surface temperature (LST) in the Lake Abaya catchment, Southern Main Ethiopian Rift. Landsat TM (1986), ETM+ (2003), and OLI/TIRS (2019) images were analyzed using supervised maximum likelihood classification in ERDAS IMAGINE 2015 and ArcGIS 10.5, supported by field observations and focus group discussions. Classification accuracy was validated with ground control points, while NDVI–LST relationships were quantified through linear regression in SPSS 21. Results revealed pronounced landscape transformation: forest cover declined from 35.1% in 1986 to 25.7% in 2019, while agricultural land expanded from 15.6% to 26.2%. The transition matrix confirmed large-scale conversion of forest and rangeland to agriculture. Bare areas exhibited the highest LST values, contrasting with cooler forested and water surfaces. Regression analysis demonstrated a strong inverse relationship between NDVI and LST, emphasizing the cooling role of vegetation in regulating surface energy balance. Overall, the findings highlight accelerating land degradation and ecosystem stress, with direct implications for microclimate regulation and food security. Strengthening sustainable land management and ecological restoration is therefore critical to mitigate the adverse impacts of LULCC in the catchment