Abstract


CYANOBACTERIA AND ALGAL COMMUNITY COMPOSTION ACROSS NUTRIENT GRADIENTS: A WITHIN AND ACROSS SYSTEM COMPARISON

Cyanobacteria blooms, some producing the liver toxin microcystin, have become an annual occurrence in several areas of the Laurentian Great Lakes. Significant research has been conducted exploring controls on bloom size and intensity. However, many questions remain about bloom species composition and potential for toxin production. We tracked phytoplankton composition across a nutrient gradient in three bays: the western basin of Lake Erie; Saginaw Bay, Lake Huron; and Grand Traverse Bay, Lake Michigan. Overwintering cells were collected from sediment at the start of the growing season and taxonomic trends were tracked from June through October. Cell count, nutrient, and physical conditions are compared for patterns within bays across physical and resource availability gradients and patterns are contrasted across bays. Preliminary results show nitrogen fixing cyanobacteria becoming dominant only during times of low nitrogen availability, but also show significant negative associations between nitrogen availability and Microcystis dominance as well as microcystin concentration

Authors

Evans, M. A., USGS Great Lakes Science Center, USA, maevans@usgs.gov

Duris, J. W., USGS Michigan-Ohio Water Science Center, USA, jwduris@usgs.gov

Givens, C. E., USGS Michigan-Ohio Water Science Center, USA, cgivens@usgs.gov

Stelzer, E. A., USGS Michigan-Ohio Water Science Center, USA, eastelzer@usgs.gov

Ecker, C. D., USGS Michigan-Ohio Water Science Center, USA, cdecker@usgs.gov

Larson, J. H., USGS Upper Midwest Environmental Sciences Center, USA, jhlarson@usgs.gov

Loftin, K., USGS Kansas Water Science Center, USA, kloftin@usgs.gov

Lenaker, P., USGS Wisconsin Water Science Center, USA, plenaker@usgs.gov

Details

Oral presentation

Session #:SS04
Date: 06/06/2016
Time: 15:30
Location: Sweeney Ballroom B

Presentation is given by student: No