Evaluating the impact of sponge city construction on urban ecosystem resilience: Utility and mechanism analyses

The sponge city pilot policy (SCPP) launched by the Chinese government is a forward-looking measure that takes into account both urban development and environmental protection. This study uses data from 284 Chinese cities spanning the period from 2007 to 2023 and employs the difference-in-differences (DID) method to examine the impact of the SCPP on urban ecological resilience (UER). The research results show that: (1) The SCPP can effectively enhance the UER and improve its resistance and recovery capabilities under extreme weather conditions. (2) From a mechanistic perspective, the policy indirectly improves UER performance through the optimizing ecological infrastructure and the promotion of industrial structure upgrading. At the same time, the environmental awareness of local governments and their emphasis on science and technology have a positive regulatory effect on the policy effect, thereby enhancing the SCPP promotional impact on UER. (3) Heterogeneity analysis indicates that the SCPP effect varies due to differences in the attributes and characteristics: in large cities, non-resource-dependent cities, key environmental protection cities, and non-old industrial base cities (4) Additionally, spatial effect analysis confirms that the SCPP not only improves local UER but also generates positive spillover effects on surrounding cities, forming a regional collaborative improvement pattern. This study addresses the gap in existing research regarding the direct correlation between SCPP and UER, providing both theoretical foundations and empirical evidence, and the enhancement of cities’ sustainable development capacity of cities.