Has the Healthy City Pilot Improved Ecological Resilience in China? Evidence from a Quasi-Natural Experiment

Enhancing ecological resilience and human well-being is key to achieving the global Sustainable Development Goals (SDGs). Within the framework of the Healthy China strategy, this paper treated China’s Healthy City pilot (HCP) policy as a quasi-natural experiment and systematically investigated its impact on ecological resilience, the underlying transmission mechanisms, and heterogeneity. Based on panel data from 286 prefecture-level cities spanning 2011–2023 and employing a spatial difference-in-differences (SDID) model, the empirical results showed that: Spatial correlation analysis indicated a significantly positive spatial correlation in urban ecological resilience across Chinese cities. The baseline regression results showed that the HCP policy significantly improved urban ecological resilience, with the resilience index increasing by 18.1% on average compared with non-pilot cities. The SDID results indicated that the policy generated positive spatial spillover effects on urban ecological resilience, and that policy effects were influenced by geographically neighboring cities. Mechanism tests showed that the Healthy City Pilot policy significantly promoted urban technological innovation and facilitated the transformation of the energy consumption structure, both of which played important roles in enhancing urban ecological resilience. Heterogeneity analysis revealed that the policy had stronger effects in eastern and northeastern cities than in central and western cities, and that large cities benefited more than small and medium-sized cities, mainly due to differences in regional location, development foundations, environmental governance capacity and policy implementation conditions.