Deposition of particulate matter of different size fractions on leaf surfaces and in waxes of urban forest species.

Particulate matter (PM) is an air contaminant in urban and industrial areas that often exceeds limit values, creating serious problems due to its harmful effects on health. Planting trees and shrubs as air filters is a way to improve air quality in these areas. However,further knowledge on species effectiveness in air purification is essential This study compared four species of tree (Acer campestre L, Fraxinus excelsior L, Platanus x hispanica Mill. ex Muenchh. 'Acerifolia', Tilia cordata Mill.), three species of shrub (Forsythia x intermedia Zabel, Physocarpus opulifolius (L.) Maxim., Spiraea japonica L.), and one climber species (Hedera helix L) that are commonly cultivated along streets in Poland to capture fine, coarse and larger particles from air. Separate gravimetric analyses were performed to quantify PM deposited on surfaces and trapped in waxes. Significant differences were found between the plant species tested. The distribution of different particle size fractions differed between and within species and also between leaf surfaces and in waxes.