Can Urban Agglomeration Policy Enhance Comprehensive Urban Resilience? Evidence from China

Recently, researchers have become increasingly interested in urban resilience, which can be used to comprehensively evaluate the quality of urban development. Although some studies have addressed the effects of China's national urban agglomeration (NUA) policy on the economic and environmental resilience of Chinese cities, scholars have not yet adequately addressed the impact of NUA on comprehensive urban resilience. Accordingly, this study introduced a theoretical framework to explore the effects of NUA on comprehensive urban resilience in China. Specifically, this study conducted a quasi-natural experiment with NUA and adopted a difference-in-differences (DID) method to evaluate its effect on China's comprehensive urban resilience. As no widely acknowledged urban resilience evaluation method yet exists, we employed an entropy-weighted "technique for order preference by similarity to an ideal solution" (TOPSIS) to assign comprehensive urban resilience values to Chinese cities at the prefecture level or above based on the multiple economic resilience index, the social resilience index, the environmental resilience index, and the technological resilience index. The results indicate that NUA not only directly improves comprehensive urban resilience but also enhances it through the mediating effects of trade openness and industrial structure upgrading. In addition, the study revealed that city heterogeneity can impact NUA's effect on comprehensive urban resilience. These results not only expand current theoretical understanding of the effects of urban agglomeration on urban resilience but also offer insights useful for improving comprehensive urban resilience to facilitate the high-quality and sustainable development of cities.