Long-Term Annual and Seasonal Patterns of Acidic Deposition and Stream Water Quality in a Great Smoky Mountains High-Elevation Watershed

摘要: The recovery potential of stream acidification from years acidic deposition is dependent on biogeochemical processes and varies among different acid-sensitive regions. Studies that investigate long-term trends seasonal variability chemistry in the context atmospheric watershed setting provide crucial assessments governing processes. In this study, water chemistries were investigated Noland Divide (NDW), a high-elevation Great Smoky Mountains National Park (GRSM) southern Appalachian region. Monitoring data 1991 to 2007 for statistically analyzed patterns by using Seasonal Kendall Tau tests. Precipitation declined over study period, where throughfall (TF) significantly 5.76 cm year−1. play key role fate transport acid pollutants. On monthly volume-weighted basis, pH TF wet deposition, did not change time remaining around 4.3, 4.7, 5.8, respectively. Per NDW area, SO42- flux 356.16 eq year−1 concentrations time. Stream remained about 30 μeq L−1 exhibiting no or patterns. retention was generally greater during drier months. NH4+ NO3- increased 0.80 1.24 year−1, fluxes 95.76 Most retained watershed, much lower than NH4+. 0.56 139.56 Overall, NDW, inorganic nitrogen exported before 1999 since then, presumably forest regrowth after Frazer fir die-off 1970s balsam wooly adelgid infestation. export winter summer During period 2007, base cations exhibit significant changes, apparently regulated soil supply. Statistical models predicting pH, ANC, SO42-, largely correlated with discharge number dry days between precipitation events deposition. Dependent precipitation, appear be adsorption, nitrification, uptake. This provided essential information aid GRSM management developing predictive future quality impacts climate change.