|Wednesday What's New: Air Pollution and Eastern Ecosystems|
|Written by Heleigh Bostwick Wednesday, 23 May 2012|
We’ve all heard about the damage to forests and lakes caused by acid rain, but there’s a lot more to the story than that. Dry depositions of air pollutants are equally damaging to ecosystems, particularly those in the Eastern US. Why the east coast? Simply put, wind blows from west to east. Air-borne pollutants generated from smog, coal-fired power plants, and other industrial sources are carried eastward. A new report from The Nature Conservancy looks at the effects that four air pollutants have on different habitats.
Air pollution in the form of sulfur, nitrogen, mercury, and ground-level ozone is derived from smokestacks and pipes from industrial sources in addition to agricultural. The study found that these pollutants are present in rivers, streams, and other water bodies. Dr. Timothy H. Tear of The Nature Conservancy, and one of the co-authors of the study reported states that, "Deposited pollutants have tangible human impacts. Mercury contamination results in fish that are unsafe to eat. Acidification kills fish and strips nutrients from soils. Excess nitrogen pollutes estuaries, to the detriment of coastal fisheries. And ground-level ozone reduces plant growth, a threat to forestry and agriculture."
EPA regulates air quality in terms of impacts to human health but not wildlife or plant life. For example, Environmental Impact Statements, which are required for any project funded by the US government--industrial or otherwise--are required to examine impacts to vegetation and wildlife from air quality emissions; however, there are no regulations per se, for plants, wildlife, their habitats, or ecosystems as a whole. The report stresses the importance of establishing air quality standards based on critical loads, defined as the “maximum level of deposited pollution that ecosystems can tolerate before harmful effects occur.”