Integrating ecosystem services into the water-energy-food-environment (WEFE) nexus for informed conservation strategies and planning in the Upper White Nile basin.

This study explores the integration of ecosystem services within the water-energy-food-environment (WEFE) nexus framework to inform conservation and development planning in the Upper White Nile basin in East Africa, an area faced with interconnected socio-ecological and climatic challenges. Employing a multi-method approach combining stakeholder valuations and biophysical mapping, we assess the spatial distribution of WEFE-related ecosystem services across the basin and compare them to current conservation measures. Findings reveal a heterogeneous distribution of ecosystem services across the basin, with environment-related services, such as carbon sequestration and environmental quality, dominating spatially (56 %), particularly in the northeastern part of the basin, while food-related services (27 %) are concentrated in the western and eastern regions. Water-related services (15 %) show highest delivery around major lakes, whilst stakeholder valuations highlight the importance of water provision, artisanal fisheries, and biodiversity across all sectors. Analysis of current protected areas indicates their moderate effectiveness in conserving key ecosystem services, with better representation of environment (17 %) and water-related services (12 %) than food (8 %) and energy services (5 %). We identified critical conservation-development conflict zones along the Uganda-Kenya border and in Rwanda-Burundi, where competing priorities for WEFE resources require integrated management approaches. Our conservation gap assessment shows significant shortfalls in meeting international protected targets, particularly for energy and food-related services, which is most pronounced in Rwanda and Burundi. Our study underscores the value of integrating ecosystem services into the WEFE nexus framework for comprehensive conservation planning, highlighting how combining biophysical mapping with stakeholder engagement can inform targeted interventions that balance ecosystem protection with sustainable development in transboundary basins.