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1. The Effect of Marsh Age on Ecosystem Function in a Rapidly Transgressing Marsh

   https://doi.org/10.1007/s10021-021-00652-6  

   Langston, Amy K.; Coleman, Daniel J.; Jung, Nathalie W.; Shawler, Justin L.; Smith, Alexander J.; Williams, Bethany L.; Wittyngham, Serina S.; Chambers, Randolph M.; Perry, James E.; Kirwan, Matthew L. (October 2021, Ecosystems)

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2. Topographically Induced Dispersion in a Salt Marsh Estuary

   https://doi.org/10.1175/JPO-D-24-0261.1  

   Garcia, Adrian_Mikhail P; Bo, Tong; Geyer, W Rockwell; Ralston, David K (November 2025, Journal of Physical Oceanography)

   Abstract The salt balance in estuaries is maintained by the outflow from the river, which removes salt from the estuary, and dispersive processes, which drive downgradient fluxes bringing salt into the estuary. We analyzed the salt fluxes in a realistic model of the North River, a tidal salt marsh estuary, using a quasi-Lagrangian moving plane reference based on the theory of Dronkers and van de Kreeke. Our study confirms their theoretical finding that in a plane moving with the tides, all landward salt flux results directly from shear dispersion, that is, the spatial correlation between cross-sectional variations in velocity and salinity. We separated cross-sectional variations in velocity and salinity not only based on their lateral and vertical components but also by distinct regions of the cross section: the main channel and the marsh. In this way, we quantified the salt flux contributions from vertical and lateral shear dispersion, as well as from trapping—the salt flux due to the difference between the mean velocity and salinity of the main channel compared to the marsh. Trapping accounted for up to half of the total landward salt flux in the estuary during spring tides but decreased to about one-quarter during neap tides. Within the channel, the primary mode of dispersion shifted from lateral shear dispersion due to flow separation during spring tides to vertical shear dispersion due to tidal straining during neap tides. These results demonstrate the important role of topographically induced dispersion on maintaining the salt balance, particularly in tidally dominated estuaries. 

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3. Processes Influencing Marsh Elevation Change in Low- and High-Elevation Zones of a Temperate Salt Marsh

   https://doi.org/10.1007/s12237-020-00796-z  

   Blum, Linda K.; Christian, Robert R.; Cahoon, Donald R.; Wiberg, Patricia L. (January 2020, Estuaries and Coasts)

   The movement of salt marshes into uplands and marsh submergence as sea level rises is well documented; however, predicting how coastal marshes will respond to rising sea levels is constrained by a lack of process-based understanding of how various marsh zones adjust to changes in sea level. To assess the way in which salt-marsh zones differ in their elevation response to sea-level change, and to evaluate how potential hydrologic drivers influence the response, surface elevation tables, marker horizons, and shallow rod surface elevation tables were installed in a Virginia salt marsh in three zones that differed in elevation and vegetation type. Decadal rates of elevation change, surface accretion, and shallow subsidence or expansion were examined in the context of hydrologic drivers that included local sea-level rise, flooding frequency, hurricane storm-surge, and precipitation. Surface elevation increases were fastest in the low-elevation zone, intermediate in the middle-elevation zone, and slowest in the high-elevation zone. These rates are similar to (low- and middle-marsh) or less than (high-marsh) local rates of sea-level rise. Root-zone expansion, presumably due to root growth and organic matter accumulation, varied among the three salt marsh zones and accounted for 37%, but probably more, of the increase in marsh surface elevation. We infer that, during marsh transgression, soil-forming processes shift from biogenic (high marsh) to minerogenic (low marsh) in response, either directly or indirectly, to changing hydrologic drivers. 

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4. Controls on Sediment Suspension, Flux, and Marsh Deposition near a Bay-Marsh Boundary

   https://doi.org/10.1007/s12237-018-0478-4  

   Duvall, Melissa S.; Wiberg, Patricia L.; Kirwan, Matthew L. (March 2019, Estuaries and Coasts)
5. Lateral Marsh Edge Erosion as a Source of Sediments for Vertical Marsh Accretion

   https://doi.org/10.1029/2017JG004358  

   Hopkinson, Charles S.; Morris, James T.; Fagherazzi, Sergio; Wollheim, Wilfred M.; Raymond, Peter A. (August 2018, Journal of Geophysical Research: Biogeosciences)