植物叶片滞尘规律研究——以北京市为例

为研究不同植物叶片的滞尘规律，该文选择北京市具有代表性的绿化植物种类作为研究对象，应用直接采样和统计分析的方法，在封闭式和开敞式两种不同环境条件下，对单位叶面积的滞尘量进行了系统分析.结果表明:①植物叶片单位面积滞尘量的变异系数普遍较大，这是由于叶片滞尘受外界环境干扰较大造成的；②同种类植物种在封闭式环境条件下叶片滞尘量明显低于开敞式环境条件下的滞尘量，说明同种类植物叶片滞尘量随着环境中粉尘颗粒物含量的增多而增大；③在开敞式环境条件下，对同株植物叶片纵向不同高度滞尘量的比较发现，“低”位的滞尘量明显高于 “高”和“中”位，这是由于北京市在开敞式环境条件下车辆行人繁多，造成路面较大程度的二次扬尘；④一天内植物叶片累计滞尘过程与时间不呈线性相关关系，这说明植物叶片的滞尘过程是一个复杂的动态过程，植物叶面的滞尘与粉尘脱落同时存在 

Airborne dust detainment by different plant leaves: Taking Beijing as an example

In order to research the dust detaining capability and its rules of different plant leaves,some representative greenery species in Beijing were chosen to systematically study the dust accumulation on the leaves of different plants in open and close surroundings by direct sampling and measurement,and statistical analysis as well.The results showed that: 1) the dust detaining amount per square meter of leaves varied significantly at large caused by the strong disturbance of external environment;2) for the same species,dust detained on the leaves in the close surroundings was obviously less than that in the open ones,illustrating that the dust detaining amount of leaves increased with the increment of particles in the environment;3) in the open surroundings,the dust detaining amount of leaves at the lower parts of plants was evidently larger than that of the 'middle' and 'higher' parts of the same plant according to the comparison of dust detaining of different leaves vertically in the same plant,because,the dust that had landed down to the road was churned up by cars and people,and dropped down to the leaves at the lower part of plants again;4) the cumulative dust detained on different plant leaves within one day period showed no linear relation with time,implying that the dust detaining process was complicated and dynamic.The leaves detain the dust and shake-out of it simultaneously.Understanding the dust detaining capability and its rules of different plant leaves systematically can be of guidance to urban landscaping.