How do China’s low-carbon pilot policies reshape urban ecological performance across time and space?

Abstract

China’s low-carbon city pilot program seeks to reconcile carbon emission reduction with economic growth and welfare improvement. This study examines whether low-carbon pilot policies (LCPPs) improve urban ecological welfare performance (EWP), the mechanisms through which these effects operate, and whether the policies generate spatial spillovers across cities. We construct a comprehensive EWP index for 273 Chinese cities from 2006 to 2023 using the entropy weight method and estimate the effects of LCPPs using a staggered difference-in-differences framework. Green technological innovation and digitalization are examined as transmission channels, urbanization is considered as a moderating factor, and spatial spillover effects are assessed using a Spatial Durbin Model. LCPPs significantly improve urban EWP, with the effects exhibiting persistence and a lagged pattern. Green technological innovation and digital transformation constitute important channels through which LCPPs enhance EWP, while higher levels of urbanization strengthen the policy effect. Spatial spillovers differ across pilot cohorts: indirect effects are negative for the first batch but become positive for the second and third batches. The policy effects also vary across regions and carbon-peaking target schedules. The findings indicate that the effectiveness of LCPPs depends on policy design, implementation maturity, urban development stages, and intercity economic linkages. Policymakers should calibrate carbon-peaking targets to local development conditions, strengthen science and education investment to facilitate green innovation, and integrate low-carbon pilot initiatives with new-type urbanization strategies to enhance positive spatial spillovers and nationwide ecological welfare gains.