MICROPLASTIC DISTRIBUTION ABOVE AND BELOW LARGE DAMS IN INDIANA, USA
Microplastics (plastic particles <5 mm in size) pose environmental threats of unknown magnitude to aquatic ecosystems. Microplastics can enter aquatic systems through wastewater effluent, breakdown of plastic debris, precipitation events, and atmospheric deposition. If ingested by aquatic organisms (e.g., filter-feeders), microplastics and sorbed toxins can be transferred through the food web, thereby accumulating in predators. Previous studies have shown that sediment and other contaminants can accumulate behind large dams. Here we investigate whether and how dams affect microplastic distribution in flowing water. Water samples were taken upstream, downstream, and within the reservoirs of three dams in Indiana, USA. Samples were filtered and then microplastics were quantified and classified. We expected to observe a higher concentration of microplastics upstream of dams than downstream due to settlement in the reservoir of less buoyant particles. Preliminary results suggest that microplastics are higher in concentration both in tributaries upstream of a reservoir and within the reservoir than downstream of a dam. Dam removal can be a controversial subject, but knowledge of microplastic transport past dams may contribute to decision-making.
Margaret Hartlage (Primary Presenter/Author), University of Notre Dame, firstname.lastname@example.org;
Whitney Conard (Co-Presenter/Co-Author), Department of Biological Sciences, University of Notre Dame, email@example.com;
Katherine O'Reilly (Co-Presenter/Co-Author), Department of Biological Sciences, University of Notre Dame, firstname.lastname@example.org;
Gary Lamberti (Co-Presenter/Co-Author), University of Notre Dame, email@example.com;