Coupling dynamics and feedback mechanisms between ecosystem service flows and socio-economic systems in the loess plateau

Ecosystem service flows (ESFs) describe the spatial transfer of ecosystem services (ESs) and offer a valuable framework for understanding the interactions between ecological systems and socio-economic systems. However, the dynamic coupling mechanisms linking ESFs with socio-economic processes remain insufficiently understood. To address this gap, this study quantitatively analyzes the spatial flow characteristics of four key ESs in China's Loess Plateau (LP) — water yield, food supply, carbon sequestration, and soil conservation — and systematically investigated their dynamic coupling with regional socio-economic systems. The results are: (1) Although the overall supply capacity of ESs in the LP has increased markedly, the rapid growth in regional demand has led to persistent supply-demand imbalances. These imbalances have driven an ongoing intensification of cross-regional ESF transmission and the expansion of the ecosystem service flow network. (2) As the intensity of ESFs increases, the structural complexity and spatial connectivity of the ecosystem service flow network improve substantially. The interdependence of ESFs among sub-basins becomes more pronounced. (3) With the accelerated development of the regional economy, sub-basins become increasingly dependent on both locally generated and externally inflow ESs. A stable, bidirectional feedback mechanism emerges between ESFs and socio-economic systems, further facilitating the evolution of the socio-ecological network toward a more integrated and coordinated structure. This study demonstrates the pivotal role of ESFs in promoting the coordination between ecological restoration and socio-economic development. The findings offer a theoretical foundation for regional ES management and the implementation of cross-regional ecological compensation mechanisms.