An ecological study of Appalachian stream chemistry suggests that the drop in acid rain might be giving a respite to the hardwood forests though it is changing biological activity in the ecosystem and increasing dissolved carbon dioxide in forest streams.
Acid rain as the name itself suggests has some Heavy adverse impacts:
� Destruction of forests, especially high altitude vegetation, if not directly then by weakening trees and leaving them vulnerable to diseases. Or by slowing the growth of forests.
� Soil biology can be seriously damaged by acid rain
� It accelerates weathering in carbonate rocks.
� Acid rain can also cause damage to certain building materials and historical monuments
� It also contributes to acidification of rivers and streams. As lakes become more acidic biodiversity is reduced. Aquatic life is threatened. Insects have been eliminated.
One would assume that by reducing the ammount of sulfur dioxide and nitrogen oxides emissions ( which cause acid rain) which are a off-spin of industrialization, into the atmosophere there would be a drop in the acid rain. This is what was done in the region.
Accordingly water quality in the streams is gradually improving from the reduced sulfur emissions, and researchers are also seeing less nitrogen from the atmosphere and in the streams. But this all is resulting in more CO2. Why?
David DeWalle, professor of forest hydrology at Penn State says:
These are unexpected results, Rising amounts of carbon dioxide in streams and soil could have implications for the forest ecosystem, and the carbon balance in general.
He thinks that by reducing pollutants emitted to the atmosphere, we are creating a different set of conditions for organisms in the soil. The rising dissolved carbon dioxide in the streams can be traced to increased respiration by these organisms.
Increased respiration is resulting in increased soil carbon dioxide and reduced amount of residual organic matter
Unfortunately according to a Penn State researcher:
Higher amounts of carbon dioxide in the soil means more of it ultimately may be emitted back to the atmosphere as a greenhouse gas.
Maybe the long period of acid rain has already polluted the ground water and altered the soil composition. Appalachian forests play a crucial role in maintaining a healthy ecosystem, and support thousands of species as well as jobs. Further research needs to be done to understand the problem. The answer is definitely not in increasing emissions of sulfur and nitrogen oxides to the atmosphere.
Via: Physorg
