HA4 Metals and Bioaccumulation
Room 16A/B, Level 4
8:00 AM - 12:00 PM, Thursday, 13 November 2003
Chair: Paquin, Paul ,
Co-chair: Schlekat, Chris ,
(507) Selenium bioaccumulation in aquatic insects occupying lotic and lentic wetlands.
Hillwalker, W1, Jepson, P1, Wallschlager, D1, 2, Anderson, K1, 1 Oregon State University, Corvallis, OR, USA2 Trent University, Peterborough, ON, Canada
ABSTRACT- The current project investigates the biogeochemical compartmentalization of selenium (Se), and aspects of ecological niche occupancy, influencing Se bioaccumulation by benthic and pelagic aquatic insects within contrasting fishless aquatic sites. A three-year seasonal sampling effort was undertaken within a lentic and a lotic fresh water system exposed to Se-contaminated water discharged from a copper smelter site, Utah, USA. Total Se concentrations were comparable between the systems for the water and sediment compartments. In contrast, both the benthic and pelagic aquatic insects collected within the lentic system contained a significantly greater body burden than the lotic system. Differences in Se chemical form in the surface water as well as distribution in the sediment compartment were apparent between the aquatic systems, though a trophic relationship in Se accumulation was not observed for either site. Our results suggest that lotic and lentic site-specific geochemical parameters and aquatic insect ecology have a mediating effect on Se bioaccumulation pattern.
Key words: bioaccumulation, selenium, site-specific, aquatic insects