Simple metrics predict salt-marsh sediment fluxes

Geophysical Research Letters
By:  and 

Links

Abstract

The growth (or decay) of salt marshes depends on suspended-sediment flux into and out of the marsh. Suspended-sediment concentration (SSC) is a key element of the flux, and SSC-based metrics reflect the long-term sediment-flux trajectories of a variety of salt marshes. One metric, the flood–ebb SSC differential, correlates with area-normalized sediment flux and can indicate salt-marsh resilience over months to years. We hypothesize that these metrics may be relevant over shorter time periods. With data from 13 salt-marsh channels, we show that sediment flux direction and magnitude can be inferred from SSC differential over a wide range of timescales. Furthermore, in settings characterized by a standing tidal wave, the water-level gradient can be used instead of velocity to compute the SSC differential, enabling less-intensive measurements that capture fundamental sediment-flux parameters. Distilling the sediment-flux trajectory into simple metrics improves sediment-budget assessment, drives geomorphic model development, and clarifies field observations.
Publication type Article
Publication Subtype Journal Article
Title Simple metrics predict salt-marsh sediment fluxes
Series title Geophysical Research Letters
DOI 10.1029/2019GL083819
Volume 46
Issue 12
Year Published 2019
Language English
Publisher American Geophysical Union
Contributing office(s) Pacific Coastal and Marine Science Center
Description 8 p.
First page 12250
Last page 12257
Google Analytic Metrics Metrics page
Additional publication details