Year Established: 2012 Start Date: 2012-03-01 End Date: 2014-02-28
Total Federal Funds: $30,000 Total Non-Federal Funds: $66,482
Principal Investigators: Melody Bernot, Daniel Elias
Abstract: Agricultural pesticides have the potential to affect receiving aquatic ecosystems. However, few studies have provided direct measures of pesticide movement within freshwaters. Atrazine, metolachlor, carbaryl and chlorothalonil have high usage rates throughout the Wabash River watershed and are potentially toxic to algae, aquatic plants, invertebrates, fish, and humans. Thus, a more comprehensive understanding of their transport and fate in freshwaters is needed to effectively manage these compounds. Proposed research will provide novel and direct measures of contaminant transport and retention in central Indiana streams. Specifically, seasonal in situ enrichment experiments of atrazine, metolachlor, carbaryl and chlorothalonil will be conducted to directly quantify dissolved and sediment movement of these agricultural contaminants. Proposed research will be guided by one primary question with related hypotheses: What factors affect transport and retention of agricultural pesticides in lotic ecosystems? Pesticide transport and retention is dependent on dissolved organic matter, discharge and individual pesticide chemical characteristics. It is hypothesized that pesticide transport will be longer during high discharge periods (i.e., spring). Further, pesticide transport will be reduced with greater abundance of organic matter. Chlorothalonil is hypothesized to be higher in sediments (sorption coefficient, Koc=1380), relative to metolachlor, atrazine and carbaryl (Koc: 200, 122, 251, respectively), which will be primarily dissolved in water and foster increased transport of these contaminants. The information gained from this research will increase our understanding of atrazine, metolachlor, carbaryl and chlorothalonil transport and retention in freshwaters and provide data necessary for effective management of these agricultural chemicals and freshwater resources.