Dynamic urban development reshapes water‒food‒ecology nexus priorities: Evidence from 335 Chinese cities

• High performance in water, food, and ecology remain scarce and spatially disparate. • Bidirectional inhibition occurs mainly within the water and ecological sectors. • Bidirectional promotion occurs most among cities with the same or adjacent incomes. • Food production in lower-middle-income cities promotes ecology in high-income. The water‒food‒ecology (WFE) nexus involves complex interdependencies, but existing studies often overlook multi-sectoral bidirectional feedback and cross-border effects. Using geographically and temporally weighted regression (GTWR) and spatial simultaneous equations, we analyse WFE interactions across 335 Chinese cities (2000–2022). Our results reveal persistent spatial disparities. Cities with high-performance in all sectors remain scarce (<5%), with high-performance cities of water clustered in Southwest China, food in Northeast China, and ecology in key ecological protection zones. We find the bidirectional promotion between sectors accounted for 16.6%. The degree of water resource exploration and utilization (W7), serving as a critical leverage point, shows bidirectional promotion with the municipal solid waste harmless treatment rate (E3) in ecology sector. Additionally, sectoral conflicts, particularly resource competition between per capita water consumption (W8) and ecological water use efficiency (W10), and land competition between agriculture and forests, intensify with urban development. Our further cross-border analysis reveals asymmetric interactions: high-income cities’ water overuse constrains ecological protection in lower-middle-income cities, whereas food production in the latter enhances ecosystems in the former. These dynamics highlight the need for differentiated governance that targets leverage points such as W7 optimization and cross-regional compensation mechanisms to address negative spillover effects. Our framework advances WFE nexus management by integrating multi-sector feedback and spatial spillovers, providing a template for global sustainability strategies.