Sediment delivery to a tidal marsh platform is minimized by source decoupling and flux convergence
Date
2020-06-27Metadata
Show full item recordCitable URI
https://hdl.handle.net/1912/26266As published
https://doi.org/10.1029/2020JF005558DOI
10.1029/2020JF005558Keyword
salt marsh; sediment transport; turbidity; flux convergence; decouplingAbstract
Sediment supply is a primary factor in determining marsh response to sea level rise and is typically approximated through high‐resolution measurements of suspended sediment concentrations (SSCs) from adjacent tidal channels. However, understanding sediment transport across the marsh itself remains limited by discontinuous measurements of SSC over individual tidal cycles. Here, we use an array of optical turbidity sensors to build a long‐term, continuous record of SSC across a marsh platform and adjacent tidal channel. We find that channel and marsh concentrations are correlated (i.e., coupled) within tidal cycles but are largely decoupled over longer time scales. We also find that net sediment fluxes decline to near zero within 10 m of the marsh edge. Together, these results suggest that large sections of the marsh platform receive minimal sediment independent of flooding frequency or channel sediment supply. Marsh‐centric, as opposed to channel‐centric, measures of sediment supply may better characterize marsh platform vulnerability.
Description
Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Earth Surface 125(8),(2020): e2020JF005558, doi:10.1029/2020JF005558.
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Suggested Citation
Coleman, D. J., Ganju, N. K., & Kirwan, M. L. (2020). Sediment delivery to a tidal marsh platform is minimized by source decoupling and flux convergence. Journal of Geophysical Research: Earth Surface, 125(8), e2020JF005558.Related items
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