Promoting the optimization of ecosystem services supply-flow-demand by integrating urban-rural metacoupling interactions

Clarifying how to systematically manage ecosystem services is crucial for addressing urban-rural conflicts and promoting urban-rural sustainable development, while ecosystem service optimization offers an effective approach. The optimization of ecosystem services encompasses not only the traditional supply and demand but also the entire process, including supply, flow, and demand, especially for the complex urban-rural socio-ecological systems. The metacoupling framework can offer a feasible theoretical approach for advancing the spatial optimization of ecosystem service supply-flow-demand and adaptively explain the interaction relationships between urban and rural regions. This study first explored urban-rural patterns and the complex characteristics of socio-ecological systems to understand the metacoupling mechanisms, including intracoupling, pericoupling, and telecoupling, between urban areas, urban-rural fringes, and rural areas. Furthermore, by integrating the spatial relationships of ecosystem services supply-flow-demand with the entire process assessment approaches, we interpreted varied urban-rural metacoupling interactions of ecosystem services nexus. Finally, a metacoupling-based ecosystem services supply-flow-demand optimization framework was developed, which considers reducing supply-demand trade-offs, balancing supply-demand deficits, and improving flow efficiency. The metacoupling framework for urban-rural ecosystem services optimization constructed in this study provides a new research perspective and adaptive theoretical approach for the comprehensive and sustainable management of urban, urban-rural fringe, rural ecosystem services.