This research project is based on the notion that habitat alteration and loss of biodiversity due to pesticide contamination is rapidly emerging as a major ecological threat in wetland and estuarine ecosystems. Initial evidence shows that the common herbicide, atrazine, may be having significant effects on South Carolina’s wetlands and saltmarshes. In aquatic ecosystems, phytoplankton are usually the most atrazine-sensitive biotic components.
As such, the investigator will determine the short-term sublethal effects of environmentally-relevant concentrations of atrazine (under high and low nutrient concentrations) on estuarine phytoplankton community structure and function. Short-term phytoplankton bioassays will be used to measure initial phytoplankton responses to different levels of atrazine and nutrient exposure. The purpose of these experiments is to determine the effects of a range of atrazine and nutrient concentrations on phytoplankton primary productivity and biomass of specific algal groups (i.e., diatoms, cyanobacteria, dinoflagellates, cryptophytes, etc.) in natural estuarine phytoplankton assemblages. These data will be used to assess “who” responds to the different levels of atrazine treatments under ambient (light, nutrient, temperature, etc.) conditions. This experimental approach is critical for understanding the mechanisms underlying phytoplankton community responses and dynamics in estuarine ecosystems.