A gradient-based analysis of ecosystem service trade-offs and synergies bundles in Wuyi Mountain National Park Region, China

Understanding interactions among multiple ecosystem services (ESs) is critical for maintaining ecosystem integrity and guiding sustainable landscape management. However, most existing studies focus on pairwise trade-offs or synergies, often combined with spatial clustering, leading to fragmented understanding and limited system-level insight. To address this, we developed a Trade-off/Synergy Gradient (TSG) framework that integrated multiple pairwise ES relationships into a continuous, gradient-based representation, emphasizing relationships among services and providing decision-oriented outputs for spatial governance. We applied this framework to the Wuyi Mountain National Park region in China. Using the InVEST, Moran’s I, and LightGBM SHAP, we quantified ES trade off synergy bundles (ES-TSBs) and identified their dominant drivers. The results indicated that: (1) the TSG framework classified ES-TSBs into five types including extreme, high conflict, neutral/mixed, high win-win, and ideal states. High win-win and neutral /mixed bundles dominated the regional landscape (68.5% to 73.7%), reflecting overall stability associated with low conflict and basic synergies. (2) ES-TSB dynamics were primarily shaped by ecosystem services themselves, while topography and climate exerted secondary regulatory influences, and socio economic factors played relatively minor roles. (3) Threshold behaviours may trigger transitions along ES-TSB stability gradients, driven by natural or economic forces that shift systems between synergy oriented and trade off oriented states. The TSG framework provides a transferable tool that translates complex multi-service interactions into actionable insights, support land-use planning, policy formulation, ecosystem conservation, and facilitating evidence based balancing of ecosystem integrity and socio economic development.