Coastal marshes attenuate storm surge and waves, protecting life and property. This green infrastructure also improves water quality and provides habitat for economically important fisheries. Similarly, floodplain vegetation reduces flood peaks, enhances bank stability, and reduces nutrient loading to river channels. Because of these benefits, resource managers advocate the replanting and ecological management of vegetated landscapes along river corridors and in coastal zones. The US spends billions of dollars each year to restore these landscapes. The restoration efforts, which include the re-establishment of vegetation and the diversion of sediment into eroded areas, require a fundamental understanding of sediment transport and retention in vegetated regions that this project will help provide. In addition to these desired societal benefits that could stem from this research, the project will also train one doctoral student, support one undergraduate student each summer, and include outreach in Boston-area middle and high schools.
This research project will develop physical predictions of sediment transport as a function of flow and vegetation characteristics. The new models will be developed through a series of laboratory experiments using model vegetation of increasing complexity that will build an understanding of how vegetation geometry and distribution within a channel impact velocity, turbulence, and sediment transport. Experiments will record velocity and channel-scale sediment flux, and will use laser-scans to track bathymetric evolution. The transfer of new models to practical application in the full-scale restoration projects will be facilitated through collaboration with the US Bureau of Reclamation.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
