中国北方地区大气污染的空间关联网络及其结构特征

Spatial Correlation Network and Its Structural Characteristics of Air Pollution in Northern China

有效改善北方地区空气质量是打赢蓝天保卫战的重要内容,随着冬季供暖季的到来,北方地区大气污染面临着卷土重来的危险,认识北方地区城市大气污染空间关联及其结构特征对于大气污染联防联控的有效实施具有重要意义。本文基于2016年1月1日至2018年12月31日中国北方地区58个城市AQI日报数据,利用非线性Granger因果检验识别大气污染的空间关联关系,并对大气污染空间关联网络的整体网络结构特征和个体网络结构特征进行分析。研究发现:第一,北方地区大气污染呈典型的非线性网络结构形态,没有一个城市能够独善其身;第二,城市大气污染空间关联网络不仅关联关系紧密,而且不具有森严的等级结构,此外,网络效率较低,网络的冗余连线较多;第三,石家庄、天津、唐山、秦皇岛、邯郸、邢台、保定等城市不仅自身大气污染严重,而且对其他城市产生溢出效应,在大气污染空间关联网络中不仅扮演着污染源角色,而且还对其他城市大气污染空间关联起到中介作用。本文建议构建北方地区大气污染空间关联网络监管体系,加强对大气污染空间关联网络的核心城市的监管并形成监督考核体系。

Effectively improving air quality in the northern region is an important part of winning the blue sky defense war.With the coming of winter heating season,air pollution in northern China is facing the risk of comeback.It is of great significance to understand the spatial correlation and structural characteristics of urban air pollution in northern China for the effective implementation of joint prevention and control of air pollution.Based on the AQI daily data of 58 cities in northern China from January 1,2016 to December 31,2018,this paper uses the Nonlinear Granger Causality Test to identify the spatial correlation of air pollution,and analyzes the overall network structure characteristics and individual network structure characteristics of the spatial correlation network of air pollution.The results show that:Firstly,air pollution in the northern region is a typical nonlinear network structure,and no city can survive on its own.Secondly,the spatial correlation network of urban air pollution is not only closely related,but also does not have a strict hierarchical structure.In addition,the network efficiency is low and the network has more redundant connections.Thirdly,Shijiazhuang,Tianjin,Tangshan,Qinhuangdao,Handan,Xingtai,Baoding and other cities not only have serious air pollution themselves,but also have spillover effects on other cities.They not only play a role as a source of pollution in the air pollution spatial association network,but also serve other cities.The spatial correlation of air pollution provides an intermediary role.This paper proposes to build a monitoring system for the air pollution spatial association network in the northern region,strengthen the supervision of core cities in the air pollution spatial association network,and form a supervision and evaluation system.