吉林市6种街道绿化树种叶片滞尘特性研究

目的]研究树种叶片滞尘特性,为滞尘型绿地树种的选择提供参考。方法]通过水浸法和图像法,测定吉林市6种常见街道绿化树种的单位叶面积滞尘量、叶片固着颗粒物粒径组成,分析微结构与叶片滞尘的关系。结果]1能够较长时间稳定地固着于叶片表面的粉尘以小粒径颗粒物为主,6种树木叶片固着PM_(10)的数量比例均超过97.76%;叶片累计固着PM_(2.5)的数量比例均超过65.33%。2在各树种滞尘量比较中,大粒径颗粒物发挥了重要作用。6种树木叶片固着PM_(10)的体积比例为47.87%~78.22%,体积最大的是金焰绣线菊(Spiraea×bumalda cv.Cold flame),最小的是杏(Prunus armeniaca L.);叶片固着PM_(2.5)的体积比例为4.41%~14.66%,比例最大的是紫丁香(Syringa oblata Lindl.),最小的是杏。36种街道绿化树种叶片滞留颗粒物、PM_(2.5)、PM_(10)总量差异显著,树种滞尘存在特异性,表现在滞尘量及粒径组成两方面。4叶片微结构对较小颗粒物(粒径20μm)滞留具有重要影响。通常,叶片的皱褶、凹凸程度越大,固着颗粒物量越多。结论]能够较长时间稳定地固着于树种叶片表面的粉尘以小颗粒物为主,固着量和粒径组成与叶片表面微结构有关。

Blade Detaining Dust Feature of Six Kind s of Street Greening Tree Species in Jilin City

Objective] To research the blade detaining dust feature, and to provide references for the selection of detaining dust green tree spe-cies.Method] water immersion method and image method were used to detect the dust detention quantity in unit leaf area , and leaf adsorbed particle size composition of six kinds of common street greening tree species in Jilin City.The relationship between microstructure and leaf dust were analyzed.Result] ① Small diameter particles could stably fix dusts on blade surface for a long time; the percentages of six kinds of tree leaves adsorbed PM10 ratio all reached more than 97.76%; blade fixation of PM2.5 cumulative quantity proportion reached 65.33% and above.②When comparing the dust detention quantity of each species, big diameter particles played a major role.The volume ratios of six kinds of tree leaves adsorbed PM10 were between47.87% and 78.22% , among which the biggest was Sp iraea × bumalda cv.Cold flame and the smallest was Prunus arm eniaca L.Volume ratios of some leaves adsorbed PM2.5 were between 4.41% and 14.66%, among which the largest proportion was the Syringa oblata Lindl, and the smallest was the Prunus armeniaca L.③ There were significant differences in leaf retention particles, PM2.5 and PM 10 in six kinds of street greening tree species .Specificity existed in the detaining dust of tree species, which was shown in two as-pects of dust amount and particle size composition .④Blade microstructure had great influence on the retention of smaller particles (particle di-ameter <20 microns).Usually, greater blade folds and concave and convex content led to larger amount of particulates .Conclusion]Small diameter particles can stably fix dusts on blade surface for a long time .Fixed amount and particle size composition are related to the surface mi-cro-structure of leaves.