Structural Characteristics and Evolution Trend of Collaborative Governance of Air Pollution in "2+26" Cities from the Perspective of Social Network Analysis

The regional and complex air pollution problem has become a major bottleneck restricting the sustainable development of regional economies and societies. Constructing a regional collaborative governance network has become a key solution to solving the cross-regional air pollution problem. By performing a social network analysis, this paper analyzes the overall structure, internal characteristics, and evolution trend of the collaborative governance network of regional air pollution by selecting the data samples of the "2 + 26" cities from 2017 to 2021. The study found that the excellent results of air pollution control in Beijing-Tianjin-Hebei and its surrounding areas are due to precise and efficient collaboration among the "2 + 26" cities. The collaborative network formed by "2 + 26" cities based on the joint initiation of severe weather emergency responses is an important measure that can help to effectively control regional air pollution problems. There is a distinct difference in the collaborative pattern in the "2 + 26" cities air pollution collaborative governance model, showing a nested-difference network structure.