Impact of farmland protection policy on urban land use efficiency: perspectives from the transformation of local government land supply strategy

Against the backdrop of food security strategies and rapid urbanization, farmland protection policy (FPP) has become crucial for curbing the disordered expansion of construction land and ensuring national food security. However, systematic empirical evidence on how these policies affect urban land use efficiency (ULUE) remains limited. Using panel data from 284 prefecture-level cities in China from 2006 to 2016, this study examines the impact of FPP on ULUE from the perspective of local government land supply strategy transformation. We employ an intensity-based difference-in-differences model and mediation analysis to estimate the policy effect and potential transmission mechanisms. The results show that FPP significantly improves ULUE, a finding robust to endogeneity tests and multiple robustness tests. The effects vary across cities with different dependence on land finance, administrative levels, and city sizes. Cities with low land finance dependence, non-key cities, and large cities respond more strongly to the policy. The land market incentive effects, resource allocation optimization effects, and land use structure optimization effects are key mediating pathways through which FPP affects ULUE. To strengthen the role of FPP in promoting ULUE, policies should include further land market reforms, optimized land supply structures, and region-specific guidance to balance farmland protection with high-quality urban development.