pH and acid anion time trends in different elevation ranges in the Great Smoky Mountains National Park

Robinson, RB; Barnett, TW; Harwell, GR; Moore, SE; Kulp, M; Schwartz, JS

HERO ID

1785428

Reference Type

Journal Article

Year

2008

Language

English

HERO ID 1785428
In Press No
Year 2008
Title pH and acid anion time trends in different elevation ranges in the Great Smoky Mountains National Park
Authors Robinson, RB; Barnett, TW; Harwell, GR; Moore, SE; Kulp, M; Schwartz, JS
Journal Journal of Environmental Engineering
Volume 134
Issue 9
Page Numbers 800-808
Abstract Quarterly base flow water quality data collected from October, 1993 to November, 2002 at 90 stream sites in the Great Smoky Mountains National Park were used in step-wise multiple linear regression models to analyze pH, acid neutralizing capacity (ANC), and sulfate and nitrate long-term time trends. The potential predictor variables included cumulative Julian day, seasonality, elevation, basin slope, stream order, precipitation, surrogate streamflows, geology, and acid depositional fluxes. Modeling revealed statistically significant decreasing trends in pH and sulfate with time at lower elevations, but generally no long-term time trends in stream nitrate or ANC. The best forecasting models were chosen based on maximizing the r(2) of a holdout data set. If conditions remain the same and past trends continue, the forecasting models suggest that 30.0% of the sampling sites will reach pH values less than 6.0 in less than 10 years, 63.3% in less than 25 years, and 96.7% in less than 50 years. The pH forecasting models explain 65% of the variability in the holdout data.
Wosid WOS:000258487800011
Url http://ascelibrary.org/doi/10.1061/%28ASCE%290733-9372%282008%29134%3A9%28800%29
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English