When released into the atmosphere, these chemical compounds constitute two of the primary causes of acid rain. The GAO report found that progress had been made in reducing sulfur dioxide emissions, but emissions from nitrogen oxides remain essentially unchanged. The Adirondack Park is dying faster than the EPA predicted and is actually losing its ability to buffer acid rain. EPA's worst-case scenario now appears to be the likely outcome. Acid rain pollutes watersheds, creating highly acidified and nitrate-laden lakes where fish are unable to survive.
Acidified soil is stripped of necessary nutrients that help plants survive cold temperatures.
Vermont's maple trees are particularly susceptible to the effects of acid rain A recent environmental conference at the University of Vermont revealed how vulnerable the state's syrup-producing maple trees are to acid rain. And Leahy cited another recent report detailing the declining air quality of America's national parks as evidence of acid rain's destructive effect. In the eastern states, total deposition of sulfur decreased 26 percent from 1989 though 1998, while total deposition of nitrogen increased 2 percent, according to the report. Nitrates also increased in 48 percent of the lakes sampled in the Adirondacks, a sensitive ecosystem that is protected under the Clean Air Act. Leahy believes the GAO report will provide the impetus for more stringent national regulation of all nitrogen oxide sources.