基于多源卫星遥感的中国城市绿地大气污染削减作用研究:Ⅰ.大气污染颗粒物

Air Pollution Reduction Effect of Urban Green Spaces in China Based on Multi-source Satellite Remote Sensing:Ⅰ.Particulate Matter of Air Pollution

颗粒物是城市大气污染的重要来源,对生态环境和人类健康构成严重威胁。文章利用数学模型和多源卫星遥感数据,量化了2000—2020年中国城市绿地对PM_(2.5)和PM 10的削减量,并分析了其时空变化及环境因素的影响。实验结果表明:植被对PM的干沉降作用呈现先波动上升再下降趋势,这种变化是因为地方政策驱动下的大气污染物颗粒物浓度骤降导致的;干沉降作用优势树种依次为:常绿阔叶>落叶阔叶>常绿针叶>落叶针叶,其中阔叶林总体占干沉降总量的89.22%;PM_(2.5)削减量与环境影响因子在时域空间上的相干性要比PM 10更加复杂,解释PM变化的最佳变量为降水。关于城市绿地干沉降作用的结论对城市大气污染防治和城市可持续发展有重要意义。

Particulate matter(PM)is a major source of urban air pollution that poses a serious threat to the environment and human health.This study utilizes mathematical models and multi-source satellite remote sensing data to quantify the reduction of PM_(2.5)and PM 10 in urban green spaces in China from 2000 to 2020,and analyzes its spatiotemporal variations and the impact of environmental factors.The experimental results show that:from 2000 to 2020,the dry deposition effect of PM_(2.5)and PM 10 on vegetation shows an initial increasing and then decreasing trend caused by the sudden drop in atmospheric pollutant particle concentration driven by local policies;the dominant tree species of dry subsidence are evergreen broad-leaved>deciduous broad-leaved>evergreen coniferous>deciduous coniferous,and the broad-leaved forest accounts for 89.22%of the total dry subsidence;the coherence between PM_(2.5)reduction and these factors is more complex than that of PM 10,with precipitation being the best variable to explain the change in PM_(2.5)and PM 10.These findings are important for the prevention and control of urban air pollution and sustainable development of cities.