In a recent Restoration Ecology paper, Institute of Ecosystem Studies President and Director Dr. Gene E. Likens, with colleagues, explores a new approach to restoring acidified streams, the addition of calcium silicate. The paper is the first to document the neutralizing effects of Wollastonite, a calcium silicate, on an acidic stream.
The research was performed at the Hubbard Brook Experimental Forest, located in the White Mountains of New Hampshire. Likens, who discovered acid rain at Hubbard Brook in the 1960s, has been investigating human-accelerated environmental change there for over four decades. A network of researchers and agencies, including over 70 scientists, has made the 3,160-hectare forest one of the most intensively studied watersheds in the world.
"Years of monitoring have documented that Hubbard Brook receives high levels of acid precipitation from emissions largely originating at Midwestern utility plants, as a result many streams on the site are acidic." Likens comments. Adding that, "The only way to successfully combat stream acidity is through improved air quality. Until that happens, we are exploring short-term methods of restoring water quality to sensitive sites."
Symptoms of acidified streams include a drop in pH, calcium, and dissolved inorganic carbon and an increase in metals like aluminum. When pH-levels decline, a stream is said to have lost its acid neutralizing capacity (ANC). Aquatic and semi-aquatic animals, such as fish and salamanders, are more prone to stress and disease when exposed to acidity and heavy metals.
Contact: Lori Quillen
Institute of Ecosystem Studies