Acid Rain StudyBy Cynthia Kirk
This is the VOA Special English ENVIRONMENT REPORT.
Researchers say lakes, soil and trees in the northeastern United States continue to suffer from the effects of acid rain. Acid rain is caused by nitrogen oxide and sulfur dioxide gases in the environment.
Energy companies were required to make more cuts in nitrogen and sulfur pollution in Nineteen-Ninety under amendments to the Clean Air Act. But researchers say acid rain still threatens fish and trees. They say much larger cuts in the gases that cause acid rain are needed.
The Hubbard Brook Research Foundation in the state of New Hampshire prepared the new study about acid rain damage. Many of the findings are similar to those of earlier studies. But the new study gives more evidence about the harm being done to plant and animal life.
Scientists blame coal-burning factories in the Ohio River valley of the middle west for most of the nitrogen and sulfur pollution in the northeast. Winds carry the pollution toward the east. It mixes with moisture and then falls as rain, snow or fog. This is called acid rain. Compounds like sulfur dioxide and nitrogen oxide in acid rain change the chemical balance of soil and bodies of water. The soil and water change from being chemically neutral to acidic.
Researchers say acid rain has led to a sharp reduction of red spruce and maple trees across the northeastern United States. Scientists had thought the trees were dying because of insects, lack of water or a warming climate. But the study suggests that acid rain weakens plant life and prevents trees from getting important nutrients.
High levels of acid rain are also affecting waterways in the northeastern states. This makes it difficult for fish, plants and other organisms to survive.
For years, lawmakers from the northeastern United States have proposed legislation in Congress to reduce nitrogen and sulfur gases in the environment. But the bills have gained little support outside the northeastern area of the country. Lawmakers from middle western states strongly oppose such laws.
Last month, a group of senators proposed legislation that would reduce the amount of acid rain gases that energy companies and other industries can release.
This VOA Special English ENVIRONMENT REPORT was written by Cynthia Kirk.