Declining Sediments and Rising Seas: an Unfortunate Convergence for Tidal Wetlands

  title={Declining Sediments and Rising Seas: an Unfortunate Convergence for Tidal Wetlands},
  author={Nathaniel B. Weston},
  journal={Estuaries and Coasts},
The availability of suspended sediments will be a dominant factor influencing the stability of tidal wetlands as sea levels rise. Watershed-derived sediments are a critical source of material supporting accretion in many tidal wetlands, and recent declines in wetland extent in several large river delta systems have been attributed in part to declines in sediment delivery. Little attention has been given, however, to changes in sediment supply outside of large river deltas. In this study… Expand
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Coastal sedimentation across North America doubled in the 20th century despite river dams
The proliferation of dams since 1950 promoted sediment deposition in reservoirs, which is thought to be starving the coast of sediment and decreasing the resilience of communities to storms andExpand
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Long-term marsh sustainability is threatened by environmental changes, especially accelerated rates of sea-level rise (SLR) and changing fluvial sediment supplies. Although direct observations ofExpand
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External sediment supply is an important control on wetland morphology and vulnerability to storms, sea-level rise, and land use change. Constraining sediment supply and net budgets is difficult dueExpand
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With sea level rise accelerating and sediment inputs to the coast declining worldwide, there is concern that tidal wetlands will drown. To better understand this concern, sources of sedimentExpand
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Investigating the roles of wildfire and changing agricultural practices in controlling the inter-decadal scale trends of suspended sediment production from semi-arid mountainous rivers finds changes in agricultural operations appear to have decreased sediment supply to the Salinas River over the late 20th to early 21st centuries. Expand
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Increased Terrestrial to Ocean Sediment and Carbon Fluxes in the Northern Chesapeake Bay Associated With Twentieth Century Land Alteration
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The Mississippi River basin was developed for agriculture at an unprecedented scale and intensity within the last 200 yr. These changes favored erosion and sediment transport, which were subsequentlyExpand
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A coupled geomorphic and ecological model of tidal marsh evolution
  • M. Kirwan, A. Murray
  • Environmental Science, Medicine
  • Proceedings of the National Academy of Sciences
  • 2007
A 3D model of tidal marsh accretion and channel network development that couples physical sediment transport processes with vegetation biomass productivity is developed that promotes a metastable equilibrium where the platform maintains elevation relative to a rapidly rising sea level. Expand
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It is shown that nutrient levels commonly associated with coastal eutrophication increased above-ground leaf biomass, decreased the dense, below-ground biomass of bank-stabilizing roots, and increased microbial decomposition of organic matter, demonstrating that nutrient enrichment can be a driver of salt marsh loss. Expand
Inputs of Sediment and Carbon to an Estuarine Ecosystem: Influence of Land Use.
The model provides estimates of water discharge, sediment inputs, and organic carbon inputs that agree reasonably well with independent estimates of these fluxes, and the day-to-day and seasonal patterns of precipitation appear more important than annual mean precipitation in controlling organic carbon fluxes. Expand