Variations of particulate matter retention by foliage after wind and rain disturbance

The effect of different leaf traits on their particulate matter (PM) retention capacity and the dynamics of the PM resuspension after disturbance by rain and wind were examined for eight common plant species in North China. The PM retention quantity and grain-size distributions were evaluated before and after rain and wind disturbance. PM retention quantities and stability differed significantly among the different species. Euonymus japonicus displayed the highest PM retention, while Yulania biondii displayed the lowest PM retention. Leaf size had a greater effect on PM retention than the presence of rough microstructures such as hair and grooves. Small leaves are more conducive to PM retention than large leaves. Leaf hair is a more effective structure for PM retention than grooves. While rain and wind can remove PM of all sizes, PM>100 μm is most easily removed. No correlation was found between leaf size, microscopic leaf structure, and the reduction percentage of different PM sizes. This study provides valuable information regarding the relationships between different leaf traits and PM retention capacity and retention stability, which will be useful for when selecting plants for air pollution mitigation.