Salt marsh loss affects tides and the sediment budget in shallow bays
Ganju, Neil K.
MetadataShow full item record
The current paradigm is that salt marshes and their important ecosystem services are threatened by global climate change; indeed, large marsh losses have been documented worldwide. Morphological changes associated with salt marsh erosion are expected to influence the hydrodynamics and sediment dynamics of coastal systems. Here the influence of salt marsh erosion on the tidal hydrodynamics and sediment storage capability of shallow bays is investigated. Hydrodynamics, sediment transport, and vegetation dynamics are simulated using the numerical framework Coupled Ocean‐Atmosphere‐Wave‐Sediment Transport in the Barnegat Bay‐Little Egg Harbor system, USA. We show that salt marsh erosion influences the propagation of tides into back‐barrier basins, reducing the periodic inundation and sediment delivery to marsh platforms. As salt marshes erode, the sediment trapping potential of marsh platforms decreases exponentially. In this test case, up to 50% of the sediment mass trapped by vegetation is lost once a quarter of the marsh area is eroded. Similarly, without salt marshes the sediment budget of the entire bay significantly declines. Therefore, a positive feedback might be triggered such that as the salt marsh retreats the sediment storage capacity of the system declines, which could in turn further exacerbate marsh degradation.
Author Posting. © American Geophysical Union, 2018. 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 123 (2018): 2647–2662, doi:10.1029/2018JF004617.
Suggested CitationJournal of Geophysical Research: Earth Surface 123 (2018): 2647–2662
Showing items related by title, author, creator and subject.
Seagrass impact on sediment exchange between tidal flats and salt marsh, and the sediment budget of shallow bays Donatelli, Carmine; Ganju, Neil K.; Fagherazzi, Sergio; Leonardi, Nicoletta (John Wiley & Sons, 2018-05-20)Seagrasses are marine flowering plants that strongly impact their physical and biological surroundings and are therefore frequently referred to as ecological engineers. The effect of seagrasses on coastal bay resilience ...
Salt marsh sediment diversity : a test of the variability of the rare biosphere among environmental replicates Bowen, Jennifer L.; Morrison, Hilary G.; Hobbie, John E.; Sogin, Mitchell L. (2011-12-17)Much of the phylogenetic diversity in microbial systems arises from rare taxa that comprise the long tail of taxon rank distribution curves. This vast diversity presents a challenge to testing hypotheses about the effects ...
Rhizosphere heterogeneity shapes abundance and activity of sulfur-oxidizing bacteria in vegetated salt marsh sediments Thomas, François; Giblin, Anne E.; Cardon, Zoe G.; Sievert, Stefan M. (Frontiers Media, 2014-06-23)Salt marshes are highly productive ecosystems hosting an intense sulfur (S) cycle, yet little is known about S-oxidizing microorganisms in these ecosystems. Here, we studied the diversity and transcriptional activity of ...