A nonlinear relationship between marsh size and sediment trapping capacity compromises salt marshes' stability
Ganju, Neil K.
Aretxabaleta, Alfredo L.
MetadataShow full item record
Global assessments predict the impact of sea-level rise on salt marshes with present-day levels of sediment supply from rivers and the coastal ocean. However, these assessments do not consider that variations in marsh extent and the related reconfiguration of intertidal area affect local sediment dynamics, ultimately controlling the fate of the marshes themselves. We conducted a meta-analysis of six bays along the United States East Coast to show that a reduction in the current salt marsh area decreases the sediment availability in estuarine systems through changes in regional-scale hydrodynamics. This positive feedback between marsh disappearance and the ability of coastal bays to retain sediments reduces the trapping capacity of the whole tidal system and jeopardizes the survival of the remaining marshes. We show that on marsh platforms, the sediment deposition per unit area decreases exponentially with marsh loss. Marsh erosion enlarges tidal prism values and enhances the tendency toward ebb dominance, thus decreasing the overall sediment availability of the system. Our findings highlight that marsh deterioration reduces the sediment stock in back-barrier basins and therefore compromises the resilience of salt marshes.
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Donatelli, C., Zhang, X., Ganju, N. K., Aretxabaleta, A. L., Fagherazzi, S., & Leonardi, N. A nonlinear relationship between marsh size and sediment trapping capacity compromises salt marshes' stability. Geology, 48(10), (2020): 966-970, doi:10.1130/G47131.1.
Suggested CitationDonatelli, C., Zhang, X., Ganju, N. K., Aretxabaleta, A. L., Fagherazzi, S., & Leonardi, N. (2020). A nonlinear relationship between marsh size and sediment trapping capacity compromises salt marshes' stability. Geology, 48(10), 966-970.
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
Effects of regular salt marsh haying on marsh plants, algae, invertebrates and birds at Plum Island Sound, Massachusetts Buchsbaum, Robert N.; Deegan, Linda A.; Horowitz, Julie; Garritt, Robert H.; Giblin, Anne E.; Ludlam, John P.; Shull, David H. (2008-10)The haying of salt marshes, a traditional activity since colonial times in New England, still occurs in about 400 ha of marsh in the Plum Island Sound estuary in northeastern Massachusetts. We took advantage of this haying ...
Forbrich, Inke; Giblin, Anne E. (John Wiley & Sons, 2015-09-29)We studied marsh-atmosphere exchange of carbon dioxide in a high marsh dominated salt marsh during the months of May to October in 2012–2014. Tidal inundation at the site occurred only during biweekly spring tides, during ...