Hierarchical Intervention or Horizontal Collaboration? Evidence from Environmental Governance Effectiveness in China

Air pollution stands as one of the most critical environmental challenges confronting nations worldwide, and investigating the differential impacts of diverse environmental governance modes holds pivotal implications for global sustainability. Based on panel data of 284 cities in China from 2012 to 2024, this research takes the Central Environmental Protection Inspection and the Air Pollution Comprehensive Control Action Plan in Autumn and Winter as quasi-natural experiments representing hierarchical intervention and horizontal collaboration, respectively, and employs a difference-in-differences model to evaluate their impacts on atmospheric pollution. Results show that (1) while both modes significantly curb atmospheric pollution, hierarchical intervention presents a weaker effect than horizontal collaboration; (2) hierarchical intervention exhibits greater effectiveness in low-pollution and high-development areas, whereas horizontal collaboration yields more pronounced effects in low-pollution and low-development areas; (3) hierarchical intervention suppresses pollution by intensifying promotional pressure, while horizontal collaboration exerts effects by advancing environmental decentralization; (4) the former exacerbates border pollution, whereas the latter does not. These findings provide substantial implications for policymakers seeking to scientifically utilize environmental policy tools to promote green and sustainable development.