Understanding the linkage between ecosystem service values and ecological risk in the Yongding River basin, China

Evaluations of ecosystem services values (ESV) and ecological risk (ER) are crucially important for sustainable ecosystem management and ecological security. While numerous studies have been conducted for ecosystem service values and ecological risk assessment, respectively, few studies have investigated their linkage and correlation, especially from a social-ecological perspective. Additionally, the correlation is inconsistent, varying among studies conducted at different spatial scales, which makes it difficult to apply to a building regional ecological security pattern. Here, taking the Yongding River basin, China as an example, we first quantified the spatiotemporal variation of ecosystem service values and ecological risk from 2000 to 2020 using the evaluation models of ecosystem service and ecological risk. We then explored the spatiotemporal correlation between ecosystem service values and ecological risk by using bivariate spatial autocorrelation model to identify areas where prioritized ecosystem management is required in the process of urbanization and ecological restoration. We found: (1) the total ecosystem service value in the basin decreased first, but then continued to increase. The ecosystem service value in 2020 was 679.27 million yuan lower than that in 2000. The ecosystem service values had large spatial variations, with higher ecosystem service values in mountainous areas along the distribution of the river systems. (2) Ecological risk also varied in space, with most areas having low and medium risk levels in 2020, resulting from an overall continued decrease of the ecological risk, and a shift from medium, high, and extremely high ecological risk to low and extremely low in general. (3) There was a negative spatial correlation between ecosystem service value and ecological risk, showing widely distributed “Low ecological risk vs High ecosystem service value” in non-urbanized areas, and “High ecological risk vs Low ecosystem service value” located in newly constructed land in the southeast corner of the watershed dominated. This is a result of combined effects of urban expansion and ecological restoration. Our findings can provide insights on regulation of ecological risk in the Yongding River basin, help build a regional ecological security pattern, and achieve sustainable development.