Achieving ecosystem service supply-demand balance through land use zoning regulation: A water-energy-food nexus perspective in Inner Mongolia, China

The water-energy-food (WEF) nexus is essential to human well-being and intrinsically dependent on ecosystem services (ESs), yet accelerating socioeconomic development has intensified resource demand and disrupted the supply-demand balance of ESs (ESs balance). Translating ESs balance objectives into locally adapted, implementable land use strategies remains challenging, particularly in ecologically fragile regions. This study proposed an integrated analytical framework linking the WEF nexus, ES supply-demand relationships, and land use structure to develop targeted zoning regulatory strategies for Inner Mongolia, China. Five key ESs representing the WEF nexus were selected, including water yield (WY), carbon sequestration (CS), food production (FP), soil retention (SR), and habitat quality (HQ), and their supply, demand, and ecological supply-demand ratio (ESDR) were assessed for 2022. A self-organizing map (SOM) was then applied to classify the study area into six ES balance bundles (ESBBs) reflecting distinct WEF nexus archetypes. Within each ESBB, piecewise linear regression was used to identify critical land use proportion thresholds for maintaining positive supply-demand balances. Results showed that: (1) Inner Mongolia faced significant overall ES deficits and spatial mismatches, with severe shortages in WY and CS. (2) The six ESBBs exhibited distinct supply-demand characteristics, ranging from the "WEF Scarcity Bundle" in the west to the "Water-Energy Ecological Regulation Bundle" in the east. (3) Critical thresholds for key land use types varied significantly among ESBBs. For instance, ESDR turned negative when construction land exceeded 22% in one bundle, but just 2% in another, well below its actual 15.77%. (4) Accordingly, differentiated land use regulatory strategies tailored to each ESBB were proposed. This study operationalizes ESs balance objectives into specific, actionable land use regulatory strategies, providing a scientific basis for adaptive management in Inner Mongolia and other ecologically fragile drylands worldwide.