Document Type
Article
Publication Date
1-1-2022
Publication Title
Science Advances
Volume
8
Issue
2
Pages
1-8
Publisher Name
American Association for the Advancement of Science
Abstract
In rivers, small and lightweight microplastics are transported downstream, but they are also found frequently in riverbed sediment, demonstrating long-term retention. To better understand microplastic dynamics in global rivers from headwaters to mainstems, we developed a model that includes hyporheic exchange processes, i.e., transport between surface water and riverbed sediment, where microplastic retention is facilitated. Our simulations indicate that the longest microplastic residence times occur in headwaters, the most abundant stream classification. In headwaters, residence times averaged 5 hours/km but increased to 7 years/km during low-flow conditions. Long-term accumulation for all stream classifications averaged ~5% of microplastic inputs per river kilometer. Our estimates isolated the impact of hyporheic exchange processes, which are known to influence dynamics of naturally occurring particles in streams, but rarely applied to microplastics. The identified mechanisms and time scales for small and lightweight microplastic accumulation in riverbed sediment reveal that these often-unaccounted components are likely a pollution legacy that is crucial to include in global assessments.
Identifier
85122859905 (Scopus)
Recommended Citation
Drummond, Jennifer D.; Schneidewind, Uwe; Li, Angang; Hoellein, Timothy J.; Krause, Stefan; and Packman, Aaron I.. Microplastic accumulation in riverbed sediment via hyporheic exchange from headwaters to mainstems. Science Advances, 8, 2: 1-8, 2022. Retrieved from Loyola eCommons, Biology: Faculty Publications and Other Works, http://dx.doi.org/10.1126/sciadv.abi9305
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
