The role of changing land use on estuarine quality depends in large part on a clear understanding of the potentially interactive effects of light quality, light quantity, and nutrient availability on phytoplankton community composition and the development of algal blooms.
This work will examine and characterize the phytoplankton community of Winyah Bay, South Carolina, a heavily impacted riverine estuary located about 50 miles north of Charleston. Characterization of phytoplankton community composition is critical because the taxonomic composition and relative abundance of different algal groups in a phytoplankton community are fundamental determinants of aquatic ecosystem structure and function. Significant alterations in phytoplankton community composition could have major negative ecological and economic impacts on the entire estuarine ecosystem. Harmful and nuisance algal blooms, decreases in water quality, alterations of trophic structure, and collapse of fisheries are all potential consequences of major shifts in community structure either at the algal group or species level. Bulk measures of community response (as measured by chlorophyll a) fail to show such shifts.
During the first year of the project, the researchers will (1) Characterize the spatial and temporal variability in underwater light quality and quantity, nutrient form and concentration, and phytoplankton community composition at nine stations along the Winyah Bay estuary, (2) Establish and run a continuous water quality monitoring station that will allow characterization of the fine scale temporal variability in water chemistry and biology, including CDOM concentrations and phytoplankton community composition, at an upstream (blackwater-influenced) site in Winyah Bay and (3) Quantify the degree of interference of high CDOM with estimates of chlorophyll a by fluorescence.