| With the rapid industrialization and urbanization of China,severe regional air pollution with PM2.5 as the main pollutant which seriously affected the economic development and public health,has become a serious social issue.In this study,the IER model combined with exposure factors was used to evaluate the temporal and spatial distribution characteristics,driving factors,spatial autocorrelation,health and economic benefits of health burden attributed to PM2.5 pollution in eastern and central China from 2013 to 2017.The regional transport matrix of PM2.5 for 18 cities of Henan Province as an example was built,by using the WRF-CMAQ model to simulate the PM2.5 pollution in January,April,July and October 2017.From the results,the regional transport contribution,transport law and transport path were quantitatively analyzed.From the health risk assessment,results showed that due to the decrease of PM2.5 concentration in the recent years,the cumulative number of avoided deaths was 106.8 thousand,and the prevented economic loss was 558.8 billion RMB.The PM2.5-related early deaths will be further decreased by 60.9 thousand,407.9 thousand and 588.0 thousand in comparion to 2017,if PM2.5 concentration could meet the Chinese Ambient Quality Standard Grade II(35 μg/m3),Grade I(15 μg/m3),the World Health Organization Air Quality Guidelines standards(10 μg/m3),accounting for 8.22%,55.05%and 79.36%of the total early deaths in 2017,respectively.The correspongding prevented economic losses will be 319 billion RMB,2137 billion RMB and 3081 billion RMB,accounting for 0.58%,3.91%and 5.63%of the total GDP of the study area in 2017,respectively.The contribution of total population,population aging,baseline mortality and PM2.5 exposure concentration to health burden was-8.54%,-39.31%,5.88%and 46.27%.Among these factors,population aging was the main reason for the increase of PM2.5-related deaths while the reduction of PM2.5 concentration was the most important factor in reducing the health burden.Strong spatial autocorrelation of PM2.5 and PM2.5-attributable health burden was found among cities.The cities with high-high clusters of PM2.5 concentration,population,deaths and mortality simultaneously,mostly located in Hebei,Shandong and Henan provinces,which should be the top priorities for joint air pollution control.During the study period,the major contributor to PM2.5 pollution was regional transport,and the transport contribution rates from within and outside Henan Province were 9.58%-44.77%and 34.01%-69.22%,respectively.The local emission contributions were found to be 14.26%-37.18%.Within Henan Province,PM2.5 pollution in internal cities was contributed more by intra-provincial transport,while border cities were more affected by extra-provincial transport.Luohe,Hebi,Xinxiang,Xuchang and Zhengzhou were the cities that were greatly contributed by intra-provincial transport.The cities that had been contributed more than 50%of the transport from regions outside Henan Province were Jiyuan,Puyang,Sanmenxia,Xinyang,Nanyang,Shangqiu,Zhoukou,and Zhumadian.The seasonal matrix of PM2.5 showed significant transport between cities and neighboring cities.The central urban cities including Zhengzhou,Xuchang,Luohe,and Pingdingshan,as the necessary cities for the transport path,have the most obvious transport effect.The cities with more net input PM2.5 than from local emissions,such as Hebi,Luohe and Puyang,are less likely to mitigate PM2.5 pollution problem by only reduce their local emissions of pollutants.Therefore actions need to be taken for regional joint prevention and control with the surrounding provinces and cities. |
