HR: 0800h
AN: B11B-0393    [Abstracts]
TI: Mercury Transport Following Storm Events from a Northern Forest Landscape
AU: * Bushey, J T
EM: jtbushey@syr.edu
AF: Syracuse University, Department of Civil & Environmental Engineering Link 151, Syracuse, NY 13244, United States
AU: Driscoll, C T
EM: ctdrisco@syr.edu
AF: Syracuse University, Department of Civil & Environmental Engineering Link 151, Syracuse, NY 13244, United States
AU: Mitchell, M J
EM: mitchell@syr.edu
AF: SUNY College of Environmental Science & Forestry, Departmental of Environmental & Forest Biology, Syracuse, NY 13210, United States
AU: Selvendiran, P
EM: pselvend@syr.edu
AF: Syracuse University, Department of Civil & Environmental Engineering Link 151, Syracuse, NY 13244, United States
AU: Montesdeoca, M R
EM: mmontesd@syr.edu
AF: Syracuse University, Department of Civil & Environmental Engineering Link 151, Syracuse, NY 13244, United States
AB: Concentrations and fluxes of mercury (Hg) species in surface waters of forested watersheds are affected by hydrological events. The mechanisms of Hg transport during events are poorly understood and yet may influence Hg bioavailability and exposure to aquatic biota. Three storm events were investigated (June, September, and November 2005) at a forested watershed in the Adirondack region of New York State, USA, with varying magnitude and intensity. Concentrations of Hg species increased during events both above and below wetlands in the watershed. While Hg flux was higher from wetland drainage, the Hg flux from the upland site exhibited a greater relative response to elevated watershed saturation. Hg species concentrations were not correlated with discharge, DOC, or TSS, with particulate Hg flux during events <20%. A counter-clockwise hysteretic response of DOC with increasing runoff contrasted with the clockwise response for Hg suggests different contributions from potential source areas for these solutes. Correspondence with elevated potassium and nitrate (p<0.05) suggests a contribution of Hg during the rising limb of the hydrograph associated with rapid delivery of throughfall Hg, potentially enhanced by hillslope hollows, to the stream channel. Wetland areas demonstrated a higher throughfall response, likely due to increased connectivity relative to the upland portion of the watershed. As the watershed saturates, Hg in discharge appears to shift to the flushing of the Hg soil pool. Our results emphasize how watershed attributes and storm characteristics affect Hg transport and bioavailability.
DE: 0414 Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)
DE: 0432 Contaminant and organic biogeochemistry (0792)
DE: 0497 Wetlands (1890)
DE: 1879 Watershed
SC: Biogeosciences [B]
MN: 2007 Fall Meeting