The upsurges in population, internal migration, and various development works have caused significant land use and land cover (LULC) changes in the Bagmati Basin of Nepal. The effects of climate change such as increased precipitation and temperature are affecting the provision of ecosystem services (ES). In this regard, this study particularly treated water yield (WY), soil loss, nitrogen export, and carbon fluctuation in the basin. Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) tools were used to carry out a comparative analysis of ES based on LULC data for 2000 and 2010 and corresponding climate data. To analyze the future period (2010–2099), we have used climate data from the multi-model ensemble (MME) of statistically downscaled and bias-corrected 12 best global climate models (GCMs). A raw GCM analysis (based on historical observational data) from 29 GCMs was done first. The results shows with a subsequent degradation of ES providers like forests and an increment in agricultural and urban areas, ES are on a verge of degradation. Furthermore, a projection of future climate patterns depicts increased precipitation and temperature. Thus, urgent measures are required for the sustainable provision of ES. Outcomes of the study are expected to help in the incorporation of ES in development policies promoting low-impact development along with maintaining ecological and economic goals. The study closes by presenting a recommendation for model application and future study needs.

Understanding the interaction between land use and climate variability in regulating the hydrology of tropical watersheds remains a significant scientific and policy challenge, particularly in regions with limited data. This study applied the InVEST Annual Water Yield model to assess hydrological dynamics in the Asa watershed, Nigeria, over the period 1991–2020, using three decades of precipitation and land-use/land-cover (LULC) data, along with uncertainty quantification. The results revealed a non-linear trend in water yield, with total annual yield increasing by 6.89% between 2000 and 2010, despite declining precipitation and rising evaporative demand, primarily driven by land-use modifications. Between 2010 and 2020, yield declined by 5.39% under further precipitation reduction, where precipitation sensitivity increased eightfold, marking a shift from land-use-dominated to precipitation-dominated hydrological controls. Surrogate modeling further confirmed precipitation as the dominant driver after 2010, highlighting that cumulative land degradation weakened the watershed’s natural buffering capacity and amplified climatic responses. These findings establish a threshold at which cumulative land degradation transforms watershed hydrology from land-use-dominated to climate-sensitive regimes, providing a transferable framework for identifying vulnerability thresholds in data-scarce African tropical watersheds.