Does urban vegetation mitigate air pollution in northern conditions?

• Published in: Environmental pollution (1987) Vol. 183; pp. 104 - 112
• Main Authors: Setälä, Heikki, Viippola, Viljami, Rantalainen, Anna-Lea, Pennanen, Arto, Yli-Pelkonen, Vesa
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Kidlington Elsevier Ltd 01.12.2013; Elsevier
• Subjects: air; Air Pollutants; Air Pollutants - analysis; Air pollution; Air Pollution - statistics & numerical data; air quality; analysis; Applied sciences; Atmospheric pollution; Biodegradation, Environmental; Canopies; canopy; Cities; Climate; Ecosystem services; environmental factors; Environmental Monitoring; Exact sciences and technology; forests; growing season; leaves; nitrogen dioxide; Passive samplers; physiology; Pollutants; Pollution; Pollution abatement; Prevention and purification methods; samplers; Seasons; statistics & numerical data; Summer; Traffic; Trees; Trees - physiology; understory; Urban vegetation; Vegetation; volatile organic compounds; winter; Europe; Finland; Passive samplers; Air pollution; Ecosystem services; Traffic; Urban vegetation; Pollution control; Motor vehicle; Urban area; Vegetation effect; Climatic condition; Passive detection; Seasonal variation; Sampler; Pollution abatement; Road traffic; Environment quality
• ISSN: 0269-7491; 1873-6424; 1873-6424
• DOI: 10.1016/j.envpol.2012.11.010

It is generally accepted that urban vegetation improves air quality and thereby enhances the well-being of citizens. However, empirical evidence on the potential of urban trees to mitigate air pollution is meager, particularly in northern climates with a short growing season. We studied the ability of urban park/forest vegetation to remove air pollutants (NO2, anthropogenic VOCs and particle deposition) using passive samplers in two Finnish cities. Concentrations of each pollutant in August (summer; leaf-period) and March (winter, leaf-free period) were slightly but often insignificantly lower under tree canopies than in adjacent open areas, suggesting that the role of foliage in removing air pollutants is insignificant. Furthermore, vegetation-related environmental variables (canopy closure, number and size of trees, density of understorey vegetation) did not explain the variation in pollution concentrations. Our results suggest that the ability of urban vegetation to remove air pollutants is minor in northern climates. ► The ability of northern urban vegetation to remove air pollutants is minor. ► Vegetation-related environmental variables had no effect on air pollution levels. ► The ability of vegetation to clean air did not differ between summer and winter. ► Dry deposition passive samplers proved applicable in urban air pollution study. The ability of urban vegetation to remove air pollutants seems to be minor in northern climates.