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Acidic deposition along the Appalachian Trail corridor and its effects on acid-sensitive terrestrial and aquatic resources

January 1, 2015

The Appalachian National Scenic Trail (AT), a unit of the National Park Service (NPS), spans nearly 2,200 miles from Georgia to Maine, encompassing a diverse range of ecosystems. Acidic deposition (acid rain) threatens the AT’s natural resources. Acid rain is a result of sulfur (S) and nitrogen (N) compounds produced from fossil fuel combustion, motor vehicles, and agricultural practices. The AT is particularly vulnerable to S and N because it passes along ridgetops that receive higher levels of acid rain than lower valley terrain, and these ridges are often underlain by bedrock with minimal ability to buffer acidic inputs. Further, there are numerous S and N emission sources across the region. In the environment, acidic deposition can lower the pH of streams and soils which can ultimately affect fish, invertebrates, and vegetation that inhabit these areas. To address this concern, the MegaTransect Deposition Effects Study evaluated the condition and sensitivity of the AT corridor with respect to acidic deposition, and defined air pollution thresholds (critical and target loads) and recovery rates. Findings indicate that additional S emission
reductions are needed to restore the AT.

Citation Information

Publication Year 2015
Title Acidic deposition along the Appalachian Trail corridor and its effects on acid-sensitive terrestrial and aquatic resources
DOI
Authors Gregory B. Lawrence, Timothy J. Sullivan, Douglas A. Burns, Scott W. Bailey, Bernard J. Cosby, Martin Dovciak, Holly A. Ewing, Todd C. McDonnell, Rakesh Minocha, Rachel Riemann, Juliana Quant, Karen C. Rice, Jason Siemion, Kathleen C. Weathers
Publication Type Report
Publication Subtype Other Government Series
Series Title
Series Number
Index ID 70158940
Record Source USGS Publications Warehouse
USGS Organization New York Water Science Center