Seeking Spatiotemporal Pattern And Driving Mechanism Of Air Pollutant Emission From Key Industries In China

China witnessed rapid economic development since the implementation of the reform and opening-up policy,meanwhile,huge energy consumption and pollutant emissions were followed.Thermal power generation and transportation sector play an important role in the national economy.Thermal power generation,which accounts for the largest proportion in the power supply structure,is the main mode of power generation,and road transportation is one of the most basic forms of transportation in China.Both are the main causes of air pollutant emission,aggravating the production of air pollutants such as SO₂,NO_x,PM_2.5and CO.In addition,vehicle exhaust emissions also emit a large number of CO.Different geographical location and socio-economic conditions exacerbate the regional differences of air pollutant emissions.Therefore,it is significant to understand the spatiotemporal characteristics and driving factors of air pollutants in thermal power generation and road transportation sector.In this study,a complete method system is established to identify the temporal and spatial characteristics of air pollutant emissions from thermal power generation and road transportation sector,and applied to 30 provincial regions in China to explore the driving mechanism and regional differences of pollutant emissions.Firstly,we extract regional air pollutant emission data from the Gaines-China model to analyze the time variation.Secondly,the distribution of eigenvalues and the change of spatial autocorrelation degree of emission in different regions are discussed by kernel density estimation and spatial autocorrelation analysis.Then,the temporal LMDI decomposition analysis method is used to identify the driving factors and quantify their contribution to the temporal variation of air pollutant emissions.Finally,two spatial analysis methods,principal component analysis and cluster analysis,and spatial LMDI decomposition analysis,are used to explore the regional spatial differences of driving factors in a specific year.The efforts made by each region in emission reduction are clarified,and the direction for further improvement is pointed out.The results show that:（1）North China and East China emit more air pollutants.Regional differences in the numerical distribution of air pollutant emissions are gradually narrowing.（2）There is a positive spatial agglomeration effect on air pollutant emissions,with a high-high agglomeration in East China and a low-low agglomeration in Northwest China.（3）The treatment technology,generation technology and power structure of the thermal power sector are the main restraining factors of pollutant emission,while the power demand and population are the promoting factors.The economic development level and population of the road transportation sector are the driving factors to promote emissions,and the contribution of the transportation sector to regional economic development is the driving factor to restrain emissions.The influence of vehicle use intensity and road transportation development level changes from a promoting role to a restraining role.（4）For the thermal power sector,the emission of pollutants in underdeveloped and surplus areas is mainly driven by the energy structure,energy efficiency and power input/output demand.In developed regions,GDP,population and degree of industrialization have a greater impact on emissions.（5）For the road transportation sector,the emissions of pollutant in developed regions is greatly affected by vehicle use intensity,road transport development level and economic development level.While in North China,the contribution of the transport sector to regional economic development is greatly affected.This study provides a reference for exploring the spatiotemporal characteristics and driving mechanisms of pollution emissions in other economic sectors or socio-economic activities.The comprehensive research framework can also be applied to explore the spatiotemporal characteristics and driving mechanisms of other sectors and pollutants,such as carbon and water pollutant emissions from agricultural sector and construction sector.The methods and results of this study can provide better decision support for the country and region to formulate more targeted pollution control strategies the air pollution in thermal power generation and transportation sectors.