Everyone is aware that trees provide numerous benefits to the environment and civilization, but removing carbon dioxide and emitting oxygen, providing shade, stabilizing soils and aesthetic beauty are just the beginning. In addition to carbon dioxide, trees are also responsible for clearing the air of other detrimental pollutants, according to a new study from the United States Forest Service.
This study is the first of its kind to directly link removal of air pollution with the improvement of human health. Even with the estimated pollution removal by trees of only 1% positive impacts are substantial. The Journal of Environmental Pollution, in a recent article, put an economic value on trees’ contribution to pollution removal; human health effects from reduced air pollution is valued at nearly $7 billion every year. While the USFS study found that pollution removal is much higher in rural areas, human health benefits are substantially increased in urban areas. With 80% of the American population living in urban areas the significance of urban forests and parks comes clearly to light.
Researchers have tested four specific known air quality offenders; nitrogen dioxide, ozone, sulfur and particulates less than 2.5 microns in diameter. In the United States approximately 130,000 deaths per year can be attributed to particulate matter 2.5 microns in size and in 2005 4,700 deaths were deemed ozone related. Other health effects related to air pollution include deleterious impacts to pulmonary, vascular, cardiac and neurological systems.
Benefits from trees vary across the country according to tree cover, while average national cover is estimated at 34.2%, regional variations range from 2.6% cover in North Dakota to 88.9% in New Hampshire. According to USFS researcher Dave Nowak “… in general, the greater the tree cover, the greater the pollution removal, and the greater the removal and population density, the greater the value of human health benefits.” Saving trees is more than just tree hugging, saving trees saves lives. Carefully consider removal of healthy trees on your property and get involved with your city or town’s garden or conservation group to help improve the air quality in your area.