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Rising sea levels and the increased frequency of extreme events put coastal communities at serious risk. In response, shoreline armoring for stabilization has been widespread. However, this solution does not take the ecological aspects of the coasts into account. The “living shoreline” technique includes coastal ecology by incorporating natural habitat features, such as saltmarshes, into shoreline stabilization. However, the impacts of living shorelines on adjacent benthic communities, such as submersed aquatic vegetation (SAV), are not yet clear. In particular, while both marshes and SAV trap the sediment necessary for their resilience to environmental change, the synergies between the communities are not well-understood. To help quantify the ecological and protective (shoreline stabilization) aspects of living shorelines, we presented modeling results using the Delft3D-SWAN system on sediment transport between the created saltmarshes of the living shorelines and adjacent SAV in a subestuary of Chesapeake Bay. We used a double numerical approach to primarily validate deposition measurements made in the field and to further quantify the sediment balance between the two vegetation communities using an idealized model. This model used the same numerical domain with different wave heights, periods, and basin slopes and includes the presence of rip-rap, which is often used together with marsh plantings in living shorelines, to look at the influences of artificial structures on the sediment exchange between the plant communities. The results of this study indicated lower shear stress, lower erosion rates, and higher deposition rates within the SAV bed compared with the scenario with the marsh only, which helped stabilize bottom sediments by making the sediment balance positive in case of moderate wave climate (deposition within the two vegetations higher than the sediment loss). The presence of rip-rap resulted in a positive sediment balance, especially in the case of extreme events, where sediment balance was magnified. Overall, this study concluded that SAV helps stabilize bed level and shoreline, and rip-rap works better with extreme conditions, demonstrating how the right combination of natural and built solutions can work well in terms of ecology and coastal protection.
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An atlas for physical and biogeochemical conditions in the Chesapeake Bay
Estuarine environments are characterized by strong spatial gradients and high temporal variability that are difficult to fully capture with discrete field measurements. This is particularly the case in the Chesapeake Bay, the largest estuary in the continental United States. This archive provides a climatological atlas of physical and biogeochemical conditions for the Chesapeake Bay based on numerical model results of 1985-2023. The atlas includes surface and bottom conditions on a fine longitude/latitude grid with a monthly frequency. The environmental variables are stored in a NetCDF file with abundant metadata that can be used in software such as QGIS, Python, R, Matlab or GNU Octave. A 50+ page documentation in PDF format provides additional information on the environmental variables, the numerical model used to generate the climatology, and an evaluation of the model skill over the period of the atlas. The documentation also includes ready-made visualizations for each environmental variable.
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- Award ID(s):
- 2148952
- PAR ID:
- 10599061
- Publisher / Repository:
- SEANOE
- Date Published:
- Edition / Version:
- 1
- Subject(s) / Keyword(s):
- Estuaries Biogeochemistry Chesapeake Bay Water quality Eutrophication Hypoxia Modeling Hydrodynamics Marine Science Acidification Carbon cycle
- Format(s):
- Medium: X Size: 150 Other: nc
- Size(s):
- 150
- Location:
- (East Bound Longitude:-75.02796; North Bound Latitude:39.609; South Bound Latitude:36.5526; West Bound Longitude:-77.40144)
- Right(s):
- Creative Commons Attribution 4.0 International
- Institution:
- Virginia Institute of Marine Science
- Sponsoring Org:
- National Science Foundation
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