Study On Spatio-temporal Evolution Of Urban Haze In China And Socio-economic Influencing Factors

Since the reform and opening up,with the rapid development of China’s economy,the problem of environmental pollution has become increasingly prominent,especially in recent years,the frequent occurrence of haze weather has seriously restricted the sustainable development of China.Haze pollution is an environmental issue,but ultimately it is an economic issue.Human social and economic activities are the main causes of haze.Since the"Tenth Five-Year Plan",China has continued to increase the protection of ecological environment,and has issued a series of laws and regulations and long-term measures on air pollution prevention and control.However,due to the fact that China is still in the stage of industrialization as a whole,and the great differences in geographical and regional space in China,there are still problems of inadequate governance and regional imbalance in haze pollution,so haze governance still has a long way to go.In order to deal with the frequent occurrence of haze events,this dissertation makes quantitative calculation and dynamic analysis on the differences of haze pollution in different regions of China,and identifies and studies the socio-economic factors of haze from the root,and further puts forward targeted governance measures,which is of great theoretical and practical significance,not only providing scientific basis for joint prevention and control of regional haze and policy-making,but also it is helpful to promote the reflection of economic growth mode and provide effective reference for promoting green sustainable development and ecological civilization construction in China.This dissertation takes 225 prefecture-level cities and above in Chinese mainland as the research object,based on the four regional perspectives of eastern,central,western,and northeast China,using remote sensing to retrieve PM_2.5 from 1998 to 2016 and PM_2.5 data from site monitoring in 2014.The classification statistics method,linear trend method,Kernel density estimation method,exploratory spatial data analysis,Dagum Gini coefficient decomposition method,and standard deviation ellipse method are used to analyze the spatial and temporal differences and dynamic evolution of haze pollution in China from the time and space dimensions.The study found that the haze pollution in China’s cities showed significant spatial and temporal imbalance characteristics.In terms of time,the urban haze in China shows a change law of"high in winter,low in summer,and middle in spring and Autumn".The concentration of PM_2.5 showed a trend of fluctuation in the whole study period,and the fluctuation degree showed that it increased first and then decreased.Although the pollution has improved in recent years,it still exceeds the standard level,the haze control is not sufficient,and there is still a certain gap between haze control and the public’s expectations.From the perspective of space,urban haze in China presents a spatial pattern of"high in the southeast,low in the northwest",with significant regional differences and spatial aggregation characteristics,and the pollution scope is shrinking.Therefore,according to the research paradigm of"pattern-process-mechanism-regulation",this dissertation constructs a DPSR theoretical model framework of"Driving force-Pressure-State-Response".Under this framework,the dissertation analyzes the influence mechanism of socio-economic factors on haze pollution,and concludes that economic development,population density,advanced industrial structure,energy consumption,scientific and technological innovation and opening-up are the main factors affecting urban haze pollution.It is also proposed that these factors have spatial spillover effects and non-linear effects on haze pollution.In order to explore the spatial relationship between social and economic development and urban haze,this dissertation establishes a spatial panel Dubin model based on environmental stress model and Environmental Kuznets Curve hypothesis,and empirically tests the key factors of haze.The results show that there is obvious space spillover of urban haze pollution in China.Local haze pollution is significantly affected by haze in neighboring areas.In terms of direct effects,economic growth has significantly exacerbated local haze pollution.Population density,energy consumption,and opening up have significant positive effects on haze pollution.Advanced industrial structures and technological innovation can significantly suppress haze emissions.From the perspective of indirect effects,China’s urban economic growth has an inverted“U”shaped space spillover effect on haze pollution in neighboring areas,obeying the EKC hypothesis.In addition,economic growth in neighboring areas also has significant spatial spillover effects on local smog,and the spillover effects between regions are greater than the spillover effects within regions.In order to further analyze the non-linear impact of socio-economic factors on haze,this dissertation constructs a spatial panel smooth transition regression model,and depicts the non-linear threshold effects between urban socio-economic development and haze in China under the role of space.Studies have again proved that there is a"local club group"effect in haze pollution.Every 1%increase in PM_2.5 in neighboring areas will result in a 0.971%increase in local PM_2.5.That is to say,the haze pollution in China manifests as the spatial correlation of"one glory and one glory,one loss and one loss".In addition,there is a complex spatial non-linear relationship between economic growth and haze pollution.Under the function of space,the emission reduction effects of economic development,advanced industrial structure,energy consumption,scientific and technological innovation and opening-up on haze will be smoothly transformed between high and low regional systems with economic growth,showing complex heterogeneity.Finally,on the basis of the previous research and analysis,combined with the successful haze management experience of developed countries,this dissertation proposes coordinated countermeasures suitable for urban haze management and social economy in China,including multi-regional joint governance,making differentiated emission reduction policies;at the same time,accelerating the development of green economy,accelerating the optimization and upgrading of industrial structure;optimizing the energy structure,and vigorously promoting technological innovation;strengthening supervision of foreign investment,actively introducing foreign advanced technology;giving full play to multiple co governance,and establishing a long-term mechanism.In short,only by adhering to green and sustainable development,can we achieve the coordinated development and"win-win"of China’s environmental quality and economic growth.Compared with the existing literature,this dissertation has some innovation in the research content,research method and research perspective:in terms of research content,a"Driving force-Pressure-State-Response"DPSR theoretical model framework is constructed.Under this framework,the impact mechanism of socio-economic factors on haze pollution is analyzed.In terms of research method,three kinds of space panel nonlinear models with individual effects are explored:SAR-STAR model,SEM-STAR model and ARAR-STAR model with both spatial autoregression and spatial error,which are further used to investigate the nonlinear effects of socio-economic factors on haze under the influence of space.From the perspective of research,based on the perspective of regional differences,this dissertation makes quantitative measurement of urban haze in China,analyzes its spatial-temporal differences and dynamic evolution,and puts forward differentiated haze emission reduction policies,providing scientific basis for joint prevention and control of regional haze.