Integrating ecosystem service flows into zoning for the management of ecological risks: A case study of the Pinglu...

Effective management of ecological risks in canal watersheds, crucial for sustaining ecosystem services and maintaining ecological integrity, is facing significant challenges due to complex human-environment interactions. Traditional zoning approaches rely primarily on static indicators, potentially overlooking the spatial dynamics of ecosystem services (ESs). To address this, this study integrates ecosystem service flows (ESFs), which are dynamic, spatially explicit representations of ES delivery, into ecological risk zoning within the Pinglu Canal Watershed in China. First, we quantified and mapped the spatial patterns of four key ESFs: water yield (WY), habitat quality (HQ), crop production (CP), and tourism & recreation (TR). Next, we evaluated ecological risks by building causal networks linking risk sources, exposure processes, and ES responses. Using these integrated risk-flow results, we delineated management zones through k-means clustering. The main conclusions are as follows: (1) Six ecological management zones were identified (33.93%, 7.48%, 2.62%, 32.63%, 22.28%, and 1.06% of the watershed), each characterized by distinct ecological functions and dominant risk attributes. Specifically, Cluster 6 requires integrated cross-sectoral management due to overlapping agricultural, biodiversity, and tourism pressures, while Cluster 3 highlights the need for land-use control and ecological corridor restoration. Other zones serve regulatory (Clusters 1 and 4), buffering (Cluster 5), or monitoring (Cluster 2) functions, forming a gradient governance framework. (2) While previous studies often assessed ecological risks based on static ES, this study integrates dynamic ESFs to account for spatial continuity and flow direction. This enables the identification of not only areas where ESs are under pressure but also the manners in which ecological risks spatially disrupt ES flow paths. (3) This integration provides a basis for targeted ecological risk coordinated management, applicable not only to the Pinglu Canal but also to similar watersheds globally.