The Impact Of Industrial Agglomeration On Haze Pollution Of Key Urban Agglomerations In China

Since haze pollution broke out in China in 2013,it has become a focus of environmental concerns.Based on satellite cloud images,it was found that urban agglomerations with high industrial densities are regions with a high frequency of haze in China,such as the BeijingTianjin-Hebei,Yangtze River Delta,and Pearl River Delta regions.Intuitively,high industrial agglomeration levels will aggravate haze pollution in urban agglomerations through scale effects and congestion effects,but industrial agglomeration will also mitigate haze pollution through economies of scale and technology spillover effects,which may present nonlinear relationships and regional heterogeneity.Therefore,this paper explores the relationship between industrial agglomeration and haze pollution based on key urban agglomerations,which is of great significance for the new economic growth to win the battle against pollution and achieve high-quality development.This paper firstly combines the theories of urban agglomeration coordination,EKC hypothesis,collective governance dilemma,and bottom-to-bottom competition to propose a framework for the impact of industrial agglomeration on smog pollution in urban agglomeration.The key urban agglomerations are considered to be the Yangtze River Delta,the Pearl River Delta,Beijing-Tianjin-Hebei,the middle reaches of the Yangtze River and Chengdu-Chongqing.Then this paper comprehensively analyzes the overall characteristics and spatial distribution evolution of industrial agglomeration and haze pollution in key urban agglomerations using methods such as trend analysis,cluster analysis,kernel density estimation,and exploratory spatial data analysis.Based on the STIRPAT model,this paper selects panel data from 92 cities in five key urban agglomerations from 2000 to 2016,constructs the SDM under the spatial random time fixed effect,and decomposes the spatial spillover effect.Finally,from a holistic and individual perspective,this article compares and analyzes the common and heterogeneous characteristics of the relationship between industrial agglomeration and haze pollution in key urban agglomerations,and proposes policy recommendations.The main conclusions of this paper are as follows:(1)Overall,the haze concentration of key urban agglomerations in China showed a trend of rising first and then decreasing,but overall rising.The level of industrial agglomeration is on the rise.The internal differences in haze concentrations and industrial agglomerations have been reduced,and no obvious differentiation trend has appeared.(2)The five major urban agglomerations can be divided into 4 categories,namely middle reaches of the Yangtze River and Chengdu-Chongqing with low levels of industrial agglomeration and relatively low haze concentrations,Beijing-TianjinHebei with relatively low level of industrial agglomeration and high haze concentrations,Yangtze River Delta with relatively high level of industrial agglomeration and high haze concentrations,Pearl River Delta with high industrial concentration level and low haze concentration.(3)Haze pollution in all key urban agglomerations has significant positive spatial correlation and spatial spillover,but there are differences in the extent of spatial spillover.(4)The industrial agglomeration of the Yangtze River Delta and the Pearl River Delta has an "N" curve relationship with haze pollution,which is in the third and second stages respectively.Industrial agglomeration in the Beijing-Tianjin-Hebei and the middle reaches of the Yangtze River has a positive linear effect on haze pollution.The industrial agglomeration of ChengduChongqing has an inverted "N" curve relationship with haze pollution,and is currently in the second stage.