Relationship between Leaf Traits and PM-Capturing Capacity of Major Urban-Greening Species

High concentrations of airborne particulate matter (PM) in urban areas are great concern to human health. Urban greening has been shown be an effective and eco-friendly way alleviate particle pollution, attention its role mitigating pollution increased worldwide. The species-specific PM-capturing capacity ten urban-greening species Seoul was evaluated by leaf functional traits (average area (ALA), specific (SLA), width-to-length ratio (W/L)), microstructures (roughness, stomata, trichomes), physicochemical (contact angle (θw), surface free energy (rs), the work adhesion for water (Wa), epicuticular wax loads (EWL)). relationships between PM adsorption leaves were revealed Pearson’s correlations principal component analysis (PCA). A gravimetric method used quantify, size, adsorbed on surfaces or embedded layers. key factors SLA, mean roughness value (Ra), stomatal size. SLA Ra adaxial negatively correlated with accumulation surfaces, while length width positively load. rs EWL affected in-wax Species-specific deposition result complicated mechanisms various traits. Three evergreen shrub species, Buxus sinica (Rehder & E.H. Wilson) M.Cheng var. insularis (Nakai) M.Cheng, Taxus cuspidata Siebold Zucc., Euonymus japonicus Thunb., efficient capturing both PM. PCA that high efficiency these three might attributable interaction size EWL. Aesculus turbinata Blume, Chionanthus retusus Lindl. Paxton, Rhododendron schlippenbachii Maxim. had intermediate ability, which a interactions among density, Wa ALA. Magnolia denudata Desr., Styphnolobium japonicum (L.) Schott, Liriodendron tulipifera L., Ginkgo biloba L. low efficiency. These four exhibited W/L, negative effects adsorption.