测定了北京市11种园林植物叶面颗粒物附着密度,利用环境扫描电镜观察比较了各测试树种叶表面微形态,测量统计了滞留颗粒物的粒径分布.结果表明,植物主要通过叶片上表面滞留大气颗粒物。上表面滞留的大气颗粒物数量约为下表面的5倍;叶片上表面滞留大气颗粒物能力由高到低的微形态结构依次是沟槽〉叶脉+小室〉小室〉条状突起,并且结构越密集、深浅差别越大,越有利于滞留大气颗粒物;测试树种叶片上、下表面PM2.5和PM10平均百分含量分别为66.7%和98.3%与43.4%和92.9%.
With eleven garden plant species in Beijing as test materials, this paper determined the adhesion density of atmospheric particles on leaf surface, observed the micro-configurations of leaf epidermis, and measured the particle size distribution of the particles. The results showed that the particles were mainly adhered on upside leaf surface, and the adsorbed amount was about six times higher than that on underside leaf surface. The particle-retainlng capability of the micro-configurations of leaf epidermis was decreased in the order of groove 〉 vein + cell 〉 cell 〉 strip protuberance. The capability of particle-retaining was higher when the micro-configurations were denser and the fall between them was larger. The mean value and the mean percentages of PM2.5 and PM10 on upside leaf surface were 66.7 % and 98.3 %, while those on underside leaf surfaces were 43.4 % and 92.9 %, respectively.