Exploring ecological compensation standards in the urbanization process: An ecosystem service value-based perspective

Understanding the spatiotemporal changes in ecosystem service value (ESV) under urbanization, as well as the supply–demand relationship between different regions, can provide a consultation for ecological compensation (EC) standards. Taking Suzhou, a typical city experiencing rapid urbanization in the Yangtze River Delta, as a case study, this paper analyzes the spatiotemporal changes in land use and ESV from 2000 to 2020. To quantify the ecosystem service flow (ESF), we apply the breakpoint formula and field strength model. Additionally, an EC standard is established, taking population, area and GDP into account while specifying compensation. The findings reveal that urbanization has led to a substantial increase in built-up land in Suzhou, accompanied by continuous reductions in farmland and water bodies. As a result, ESV decreased from 153.07 billion CNY to 138.81 billion CNY. Furthermore, the research identifies a spatial pattern where ESV increases with distance from the city center but decreases with distance from the lake center. This pattern suggests a directional flow of ESV from lakes to cities. Notably, ESF mainly occurs in the southwestern and central areas of Suzhou, with areas closer to Taihu Lake experiencing greater ESV transfer. The transfer value ranges from 5.11 and 32.57 billion CNY. There is an imbalance between the supply and demand of ecosystem services. Therefore, specific county-level cities in Suzhou, namely, the Kunshan District and Industrial Park, emerge as contributors of EC and should contribute 71.94 and 80.74 billion CNY, respectively, to other cities. By formulating a novel EC policy for Suzhou, this paper provides a scientifically informed reference for promoting sustainable development.