ANTHROPOGENIC LITTER IN URBAN STREAMS: SPATIAL DISTRIBUTION OF PLASTIC AND ITS ROLE IN LEAF LITTER BREAKDOWN
Anthropogenic litter (i.e., trash; AL) is an emerging ecological concern worldwide. Marine research implicates rivers as a major source of AL to oceans, but little is known about its distribution and effects on ecological processes within urban streams. Previous studies suggest that plastic AL in rivers (i.e. bags, wrappers) becomes trapped in debris dams and overhanging vegetation that also accumulate leaf litter and coarse particulate organic matter. In forested streams, debris dams are critical sites of leaf breakdown and habitat for stream biota. We measured spatial distribution of AL within 3 debris dams and 3 non-debris dam pairs, spaced ~2-3 km apart in 3 urban streams in Northeastern IL, USA. We then measured leaf breakdown, bacterial and macroinvertebrate communities in 3 litter bag treatments: leaves alone, plastic alone, and mixed. We expect the greatest plastic AL density occurs in debris dams, and that plastic reduces leaf breakdown by reducing oxygen levels, thereby lowering abundance of microbial decomposers and macroinvertebrate consumers. Results will show how the spatial distribution of AL drives its capacity to alter fundamental processes in urban streams.
Lisa Kim (Primary Presenter/Author), Loyola University Chicago, firstname.lastname@example.org;
Samuel Dunn ( Co-Presenter/Co-Author), Loyola University Chicago , email@example.com;
Timothy Hoellein ( Co-Presenter/Co-Author), Loyola University Chicago, firstname.lastname@example.org;