How Does Leaf Surface Micromorphology of Different Trees Impact Their Ability to Capture Particulate Matter?

Abstract

Particulate matter (PM), including PM10 and PM2.5, has a major impact on air quality and public health. It has been shown that trees can capture PM and improve air quality. In this study, we used two-way ANOVA to investigate the significance of micro-morphological leaf surface characteristics of green trees in capturing PM at different parks in Beijing. The results show that leaf structure significantly impacts the ability of plants to capture PM. Pinus tabuliformis Carr. and Pinus bungeana Zucc. were mainly impacted by the density of stomata, waxy cuticle, and epidermis, while the major contributor to PM retention in other test trees, including Acer truncatum Bunge, Salix matsudana Koid., Populus tomentosa Carr. and Ginkgo biloba Linn. was leaf roughness. There were significant variations in leaf-droplet contact angle (representative of leaf wettability) and the ability of trees to capture PM (p < 0.05): the bigger the contact angle, the less able the plant was to capture particulate matter.

Designing vegetation barriers for urban air pollution abatement: a practical review for appropriate plant species selection

“…However, Zhang et al 111 observed a difference in significance of individual features between broadleaved and coniferous species: increased leaf micro-roughness (characterised by grooves and ridges on the leaf surface) was found to correlate with increased deposition to broadleaves, whereas stomatal density and amount of epicuticular wax were found to positively correlate with deposition to coniferous (needle) leaves. These findings were corroborated by a similar, subsequent study 112 .…”

“…for individual pollutant types is currently unclear and an area for further research 118 . However, it may be generalised that rough leaf surfaces (including grooves, ridges and trichomes) are more beneficial than smooth surfaces for particle deposition, that epicuticular wax is beneficial (particularly for deposition to conifers 111,112 ) and that stomatal traits play a significant role that warrants further investigation. These points conform to different processes outlined in Supplementary Section S1, which highlights that different surface features will vary in influence for different target pollutants.…”

“…Similarly, plants with low stomatal conductance can tolerate relatively high levels of gaseous pollution, but are inefficient for gaseous pollutant removal, and may therefore be better suited to locations where PM attenuation is a significant focus 93 . Micromorphological structures around stomata, including waxy rings and cuticular arches, may also help to protect plants against PM pollution, although further research into this is needed 112 .…”

Urban Vegetation in Air Quality Management: A Review and Policy Framework

“…Plant level study [10][11][12][13][31][32][33][35][36][37][38][39][40][41][42][43][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59]65,69,73] Local scale [14][15][16][17]19,[21][22][23][24][26][27][28][29]34,44,63,75,76] Neighbourhood scale [18,…”

Screening potential plant species for arresting particulates in Jharia coalfield, India

“…The capacity of plants to check air pollution is well recognized and cited in the standard literature on numerous occasions [2][3][4][5]. Foliar uptake [5][6][7] of metal and metalloid particulates is reported by many authors [8][9][10][11].…”