title: Accumulation of particles on the surface of leaves during leaf expansion.
abstract: Plants can effectively remove airborne particles from ambient air and consequently improve air quality and human health. The accumulation of particles on the leaf surfaces of three plant species with different epicuticular wax ultrastructures, such as thin films, platelets and tubules, was investigated during leaf expansion in Beijing under extremely high particulate matter (PM) concentration. The accumulation of particles on the leaf surfaces after bud break rapidly reached a high amount within 4-7 days. Rainfall occasionally resulted in a considerable increase in the accumulation of particles on the leaf surfaces at a high PM concentration, which resulted from the wet deposition of PM, and balanced the amount of PM on the leaf surfaces over a longer period. The equilibrium value of the particle cover area on the adaxial leaf surface of the three test species in this study was 10%-50% compared with 3%-35% on the abaxial leaf surface. The epicuticular wax ultrastructures contributed significantly to the PM adsorption of the leaves. The capability of these ultrastructures to capture PM decreased in the following order: thin films, platelets and tubules. The ridges (at a scale of 1-2 μm) on the leaf surfaces were more efficient at accumulating PM, particularly PM2.5, compared with the roughness (P-V distance) at a 5-20-μm scale.
authors.affiliation: State Key Laboratory Incubation Base of Urban Environmental Processes and Digital Simulation, College of Resource Environment and Tourism, Capital Normal University, Beijing 100048, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: State Key Laboratory Incubation Base of Urban Environmental Processes and Digital Simulation, College of Resource Environment and Tourism, Capital Normal University, Beijing 100048, China. Electronic address: gonghl@cnu.edu.cn.
authors.forename: Huili
authors.initials: H
authors.lastname: Gong
authors.affiliation: State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Wenbo
authors.initials: W
authors.lastname: Liao
authors.affiliation: Public Meteorological Service Center, China Meteorological Administration, Beijing 100081, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000068476:Beijing; D004784:Environmental Monitoring / Q000379:methods*; D052638:Particulate Matter / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter
keywords: Epicuticular wax ultrastructures; Leaf surface contamination; Leaf surface roughness; Lotus effect; Particulate matter