Spatio-temporal characteristics and influencing factors of the coupling coordination of the water-energy-food nexus in Northeast China

As critical components for sustainable development, water, energy, and food resources form an interdependent system that supports regional socioeconomic progress. To alleviate resource constraints and advance sustainability in Northeast China, this study constructs a multidimensional assessment framework for the water-energy-food (WEF) nexus by integrating methodologies including composite index evaluation, coupled coordination modeling (CCDM), spatial autocorrelation analysis (ESDA), and spatiotemporal regression (GTWR). Our analytical framework systematically investigates the evolutionary patterns and driving mechanisms of inter-resource coordination. Key findings reveal a phase-fluctuating yet progressive enhancement in the composite development index, ascending from 0.41 (2003) to 0.49 (2021), with energy subsystems demonstrating predominant influence. Coupling coordination levels (0.62-0.69) currently reside in the elementary harmonization phase but are projected to attain intermediate coordination by 2028. Spatial analysis uncovers heterogeneous regulatory effects across urban centers, particularly noting population density's dual-directional impacts on system coordination among the studied 40 cities. These empirical insights culminate in evidence-based policy recommendations for optimizing WEF synergistic governance, presenting a replicable analytical paradigm for regional resource management studies.