The Spatial-temporal Change of PM2.5 Concentration and Its Relationship with Landscape Pattern in East China
Atmospheric PM2.5 is one of the primary pollutants affecting air quality.Therefore,how to effectively monitor and manage PM2.5 concentrations is of great significance to the sustainable development of ecological quality in China.Based on a series of auxiliary parameters,i.e.,Top-of-Atmospheric reflectance(derived from remote sensing imageries),meteorology,and land use,a Random Forest(RF)model was developed to esti-mate ground-level PM2.5 concentrations in the contiguous Yangtze River Delta-Fujian(YRD-FJ)region locat-ed in East China in 2016,2018 and 2020.The correlation between the spatial distribution of PM2.5 concentra-tions and landscape patterns in YRD-FJ region using 3-period land classification data was carried out.The re-sults show that(1)the R2 between the PM2.5 concentrations estimated by the RF model and the ground-level measured values in YRD-FJ region in 2016,2018,and 2020 are 0.91,0.89,and 0.90,respectively;the RMSE are 9.07、10.19 and 8.03 μg/m3,respectively.(2)The annual average PM2.5 concentrations in YRD-FJ region showed a trend of year-on-year decrease from 2016 to 2020,and its spatial distribution was generally in the pattern of"Jiangsu>Shanghai>Zhejiang>Fujian".(3)Reasonable control of the landscape proportion of cropland,built-up land and water bodies,and reduction of their landscape dominance and edge density are conducive to alleviating the annual average PM2.5 concentrations.Additionally,appropriate increase in forest oc-cupancy,edge density,and shape complexity are beneficial to reducing PM2.5 concentrations.Our results could provide the scientific basis and decision-making reference for the control of regional air pollution and landscape pattern planning.
NETL
NSTL
万方数据
