Urban Vegetation and their Relative Ability in Intercepting Particle Pollution (PM2.5)

Urban landscape vegetation as a component of urban forest ecosystem can provide phyto-mitigation and phyto-remediation for improving urban environment and quality of life. However, information on relative contribution of vegetation are limited. The results of this study provide additional needed information toward understanding and efficient management of our urban forests. Relative ability of common Southeastern landscape shrub and tree species in removing particulate pollution of less than 2.5 micron (PM 2.5) were quantified and compared. A modern plant-air pollution laboratory system (PALS) designed to measure fluxes of pollutants to plants was used. Tree and shrub species of similar age and size were randomly exposed to a predetermined concentration, simulating air in polluted urban areas (40 g /m3) . PM2.5 removal rate (g PM2.5 /hr) for each species was expressed on the basis of leaf area ((g PM2.5 /dm2/hr) and leaf biomass ((g PM2.5 /g/hr). Statistical analysis indicated that shrubs and trees remove significant amount of atmospheric PM2.5 under a controlled environment. Duncan Multiple Range Test provided the relative comparisons of the experimental species in terms of their ability to remove PM2.5.