Spatial And Temporal Distribution Characteristics Of PM_2.5 And Impact Mechanism Of Land Use Spatial Distribution

As the problem of air pollution becomes more and more serious,tracking the temporal and spatial distribution characteristics of PM_2.5,identifying and revealing the influence mechanism of complex elements is of great significance for targeted environmental governance.To this end,utilizing EOF,ESDA,CA,MLR,BRT and other methods to explore the temporal and spatial distribution characteristics of PM_2.5 and quantitatively measure the spatial distribution of land use in different seasons in Weifang’s contribution to PM_2.5 and its dynamic difference.The main conclusions of the study are as follows:1)In terms of the temporal and spatial distribution characteristics of PM_2.5,there are three main distribution patterns of PM_2.5concentration.Specifically,the four seasons are high in the west and low in the east,the PM_2.5 concentration in autumn and winter is radiating from high to low,and inward convergent type in spring and summer.There is significant spatial autocorrelation in the PM_2.5 concentration of all administrative divisions in Weifang,with the strongest autocorrelation in summer.The PM_2.5concentration of the administrative divisions of Weifang shows different degrees of spatial dependence and spatial heterogeneity.The agglomeration changes in Weicheng,Gaomi and Zhucheng affect the global autocorrelation of the four seasons.The spatial aggregation situation is basically the same in the four seasons,that is,hot spots are mainly distributed in the west,with Qingzhou as the core;Cold spots are mainly distributed in the east,with Fangzi as the core.Summer shows the highest agglomeration and spring agglomeration is the lowest.2)In terms of land use impact mechanism,When the area distribution of grassland and woodland is around 8%and 20%,respectively,PM_2.5 pollution in Weifang can be significantly suppressed.When the water area and branch road density distribution are less than 8%and 0.7,respectively,and the construction land area distribution is greater than 11%,PM_2.5pollution will be significantly increased;the impact of garden land and cultivated land on PM_2.5 has seasonal characteristics.the spatial distribution of the other four land use types has no significant impact on regional PM_2.5.With the cold weather,the inhibitory effect of urban vegetation distribution on PM_2.5 gradually decreases,while the promotion of PM_2.5 by the distribution of artificial facilities such as construction land and roads is gradually increasing,which is closely related to the decline of urban green vegetation in autumn and winter.Based on this,Weifang should strengthen the prevention and control of winter pollution,expand the distribution pattern of evergreen vegetation,and quantify the optimal land use spatial layout plan according to the development of regional urbanization,so as to utilize the limited green space and maximize the mitigation of PM_2.5 Pollution.Figure 16;Table 10;Reference 98...