PARENT SESSION
Organized Oral Session 5: Mercury cycles: Sources, mass balances, bioaccumulation, and options to manage affected systems
Organizer(s): EPH Best, JG Wiener, and D Planas
Monday, August 8, 8:00 AM - 11:30 AM, Meeting Room 511 C, Level 5, Palais des congrès de Montréal
Relationship between metal concentrations in Corbicula fluminea tissue and land use in a large river system.
Peltier, Gretchen*,1, Meyer, Judy1, Hopkins, William2, 1 Institute of Ecology, University of Georgia, Athens, GA2 Savannah River Ecology Laboratory, Aiken, SC
ABSTRACT- Rivers and streams in urban landscapes receive a multitude of anthropogenic inputs including urban/stormwater runoff, wastewater effluent, agricultural runoff, and effluent from coal-fired power plants. Previous studies in the Chattahoochee River, a large river system in Georgia, found elevated metal concentrations in macroinvertebrates and fishes at sites representing a gradient of urbanization. However, no spatial trend was evident. In this study we investigated the contributions of arsenic, selenium, cadmium, and mercury associated with different land uses in the Chattahoochee River with the indicator species Corbicula fluminea. Metal analyses were conducted for nine individual clams collected from fifteen tributary streams draining five different land use types: agriculture, forest, urban, coal-fired power plant (CFPP), and wastewater. Mean concentrations of arsenic and selenium were significantly higher (3.89 and 10.89 ppm dry mass) at the CFPP sites. Cadmium concentrations were the significantly higher at the urban and CFPP sites (2.84 and 3.36 ppm dry mass). Forested sites had the highest concentrations of mercury (0.36 ppm dry mass). CFPP and urban land use types were associated with elevated concentrations of arsenic, selenium, and cadmium in the Chattahoochee River. The elevated tissue concentrations of metals in Corbicula fluminea demonstrate the potential for elevation of metals in upper trophic levels of an urban aquatic food web.
Key words: Corbicula fluminea, selenium, cadmium, watershed