Automated monitoring and air pollution in border regions

Automated monitoring provides an innovative solution to the persistent challenge of border pollution governance. Leveraging the quasi-natural experiment of China's nationwide deployment of automated air monitoring stations, this study systematically examines the impact of automated monitoring on air pollution in provincial border cities and its underlying mechanisms. Using a triple-difference model incorporating the border variable, we find that PM2.5 concentrations in border cities decreased by 2.43 % more than in non-border cities after the installation of monitoring stations, indicating that automated monitoring effectively mitigates the long-standing border effect of air pollution. The governance effect is achieved through three primary mechanisms: (1) legal-spatial expansion effect, characterized by a significant increase in environmental penalties for border firms; (2) regulatory avoidance effect, evidenced by a simultaneous reduction in the number of surviving industrial enterprises and polluting firms in border regions; (3) rent-seeking suppression effect, manifested as significantly reduced rent-seeking costs for border firms. Further analyses reveal that while automated regulation suppresses industrial activities in border regions, it generates significant fiscal revenue and health benefits, resulting in a net benefit of 50.04 billion yuan for these regions.