How do city local government land finance spatial interaction strategies affect urban carbon productivity? Evidence from China’s Yangtze River Basin

This study builds on the fiscal decentralization and promotion tournament theories. Utilizing 12 years of panel data from 108 cities in the Yangtze River Economic Belt, we measure the urban carbon productivity index through a super-efficient SBM model that incorporates undesired outputs. We then analyze the effect of local land finance strategy interaction on urban carbon productivity and its mechanism using a spatial self-lagging model. Our key findings reveal: (1) Local governments exhibit mimetic spatial strategy interactions in land finance behavior, both from a geographical distance perspective and when combining economic development levels with geographical distance factors; (2) the interactive behavior of local land finance strategy has a significant inhibitory effect on urban carbon productivity, thereby leading to a loss of urban carbon productivity; (3) the local land finance strategy interaction causes a reduction in urban carbon productivity by changing the cross-city foreign direct investment strategy interaction, environmental regulation strategy interaction, and industrial structure strategy interaction. To achieve these goals, China should foster healthy competition among cities regarding land finance and promote “three-way synergy” between opening up, environmental protection, and industrial upgrading. These coordinated efforts aim to boost urban carbon productivity in the Yangtze Basin while offering developing countries a fresh approach to watershed governance focused on carbon reduction goals.