Researchers Start Major Study of Acid Rain Effects on Forests

Researchers have begun a massive study of the effects of acid rain and snow on forests.

The four-year, $8-million project is the largest privately funded study of its kind in the United States, officials of the Electric Power Research Institute of Palo Alto said.

“The health of forests and the impact of acidic deposition is one of the most active aspects of the environmental pollution debate,” said John Huckabee, the institute’s ecological studies program manager.

“In this study,” he said, “we seek the necessary scientific understanding of the factors and the interactions behind forest decline.”

Several Hypotheses

Scientists have proposed several hypotheses to explain the death of trees in some areas and the decline of some forests: acid rain, the effects of aluminum, ozone and nitrogen as well as a number of natural causes.

Some environmentalists say growing industrial emissions of sulfur dioxide, along with oxides of nitrogen from motor vehicles and industrial smokestacks, pose a major threat to forests, lakes and rivers.

Acid deposition forms when oxides of sulfur or nitrogen mix with atmospheric water to make sulfuric or nitric acid.

“This will be the first time that researchers have attempted to mathematically document how atmospheric deposition, the canopy--or tops of trees--and soil processes are linked to a forest’s nutrient status, which in turn affects the forest’s productivity,” Huckabee said.

Scientists will analyze what effects of wet and dry deposition processes have on the canopy and forest floor; whether high elevation forests have a higher level of deposition than those at lower altitudes, and what biological and chemical factors govern the levels and rates of saturation of sulfur, nitrogen and hydrogen ions.