Study Finds Major Acid Rain Damage in Northeast

By Pamela Ferdinand
Monday, March 26, 2001

Although some emissions that cause acid rain have been reduced, the Northeast is still suffering its harmful effects with far greater damage to the environment than previously thought, according to a major new study by the nation's leading acid rain researchers.

Using as illustrations trees deteriorating from malnutrition and fish dying of heart attacks in polluted waters, researchers convened by the Hubbard Brook Research Foundation in New Hampshire concluded that federal emissions limits intended to remedy acid rain are inadequate.

Regulatory controls cut sulfur dioxide emissions, but nitrogen emissions have increased in some parts of the region and dramatically reduced limits are needed, the researchers said.

The environment has been so fundamentally altered by acid rain, researchers said, that even if the most stringent proposal passed Congress today, it could take up to 50 years to restore a healthy chemical and biological balance from the sugar maple groves of Pennsylvania to the lakes and streams of upstate New York.

"When we passed the Clean Air Act Amendments in 1990, people just breathed a collective sigh of relief and said, 'Whew, that problem is gone.' And it's not gone," said Gene E. Likens, director of the Institute of Ecosystem Studies in Millbrook, N.Y. "We have a long way to go to protect sensitive ecosystems."

The acid rain issue faded from public discussion in the 1990s as policy concerns shifted to climate change and the threat of global warming. Federal funding for research dropped sharply, with programs directly benefiting the National Acid Precipitation Assessment Program receiving about $3 million in 1998, from $25.3 million a decade ago.

Environmentalists said they hope the latest data -- to be published in the March issue of the journal BioScience -- will renew concern about acid rain.

"It sends a message loud and clear that the job isn't done yet and the [emissions] cuts are going to have to be deep in order to ensure that forests and ecosystems can recover in the next half-century," said Bruce Hill of the Boston-based Clean Air Task Force.

Many of the latest data were compiled at the 7,800-acre Hubbard Brook Experimental Forest in the White Mountains of New Hampshire. The living laboratory is one of the most influential centers of environmental research and is where Likens became the first scientist to discover acid rain in the United States in 1972.

Acid rain occurs when sulfur dioxide, nitrogen oxides and ammonium combine with water vapor in the atmosphere and create acidic solutions. Sulfur is produced primarily by power plants that burn fossil fuels. Nitrogen oxides are primarily emitted by automobiles, and ammonium comes from livestock waste and fertilized soil.

Calcium and other minerals in the soil can neutralize some acid when it is redeposited on earth, but that ability has diminished over time. In a 1990 report to Congress, the National Acid Precipitation Assessment Program concluded there was insubstantial evidence that acid rain caused the decline of trees other than red spruce growing at high elevations.

But the latest data suggest the impact has been broader and more insidious. Pools of acid have built up in forests, altering soils and depriving tree roots of essential nutrients, and heavily acidified lakes and streams have become toxic to plants, fish and other organisms unable to survive abrupt chemical change, the report found.

Specifically, acid rain has contributed to the decline of red spruce trees throughout the eastern United States by sapping calcium from the foliage and making the trees vulnerable to freezing temperatures, researchers said. Since the 1960s, more than half of large-canopy red spruce in the Adirondack Mountains of New York and the Green Mountains of Vermont and approximately one-quarter of large-canopy red spruce in the White Mountains have died, according to the study.

Acid rain has also led to the decline of sugar maple trees in central and western Pennsylvania, whose thinned crowns evidence reduced growth and high mortality rates.

The water quality of lakes and streams also has been impaired, according to researchers, who said 41 percent of Adirondack region lakes and about 15 percent of lakes in New England exhibit signs of acidification. Elevated concentrations of aluminum have been measured in waters throughout the Northeast, with the potential to disrupt the saltwater balance in fish and cause heart attacks when their red blood cells rupture.

"Not only is it a lingering problem, but it has had far greater impacts than 10 years ago most people thought it would have," said Kathleen Fallon Lambert, executive director of the Hubbard Brook Research Foundation.

An additional 40 percent reduction in sulfur dioxide emissions from power plants beyond the requirements of the 1990 Clean Air Act amendments would help, researchers said. An 80 percent reduction would hasten more significant improvements and could allow some streams in watersheds similar to the Hubbard Brook forest to change from acidic to non-acidic in roughly 20 to 25 years.

But such stringent controls would likely face strong political opposition. In his decision not to impose stricter limits on carbon dioxide emissions, President Bush said they would create more reliance on natural gas to generate electricity and drive up already high energy costs.

More time is needed for current efforts to take full effect, according to Dan Riedinger, spokesman for the Edison Electric Institute, a Washington-based electric company trade association.

"Not to dismiss the findings of the report, but they are not particularly surprising, and we think the report prejudges the outcome and the effectiveness of the acid rain program," Riedinger said.

A bipartisan group of senators led by James M. Jeffords (R-Vt.) and Joseph I. Lieberman (D-Conn.) introduced legislation earlier this month that would restore carbon dioxide emissions to 1990 levels and reduce sulfur dioxide emissions by an additional 75 percent.

Nitrogen emissions would be cut by 75 percent from 1997 levels, and power plants would be required to comply with the most recent pollution control standards. Similar legislation is expected to follow in the House.

"The longer we wait, the more damage is going to be done, and the longer it's going to take for recovery," said Sarah Thorne of the Society for the Protection of New Hampshire Forests.