Closing the loop on land: Zero-Waste City pilots and urban land green use efficiency in China

Strategies for solid waste management have been widely implemented to alleviate resource limitations and mitigate environmental harm; nevertheless, research on their efficacy and the mechanisms by which they influence urban land green-use efficiency is still limited. Utilizing China’s Zero-Waste City pilot program as a quasi-natural experiment, we assemble panel data for 284 prefecture-level and higher cities from 2010 to 2024 and assess policy impacts via a staggered difference-in-differences methodology. The pilots markedly improve the efficiency of green land use in urban areas, with estimates robust to placebo tests, various outcome measures, exclusion of the four centrally governed municipalities, propensity score-matched difference-in-differences, instrumental-variable specifications, and double machine learning techniques. Mechanism testing indicates three channels: increased green technological innovation, reduced per-capita municipal solid waste collection, and enhanced environmental regulatory intensity. The heterogeneity analysis reveals that the effects are more pronounced in cities with lower industrial development; regionally, the impact is most substantial and statistically significant in western China, positive yet weaker in the central region, and minimal and statistically insignificant in eastern cities. This research connects solid-waste governance to land-performance outcomes, enhancing the body of literature on environmental policy and land-focused green transformation.