Tidal wetlands are an important geomorphic and ecological feature of the coastal zone. Our projects deal with the physical forcings that affect wetland stability over event-to-annual timescales, including wave attack, sediment supply, and sea-level rise.
Tidal wetland complexes are geomorphic features composed of vegetated marsh plain, intertidal flats, and tidal channels. The stability of a tidal wetland complex is a function of interconnected biogeomorphic and physical processes. We are primarily studying the influence of sediment supply through tidal channels, wave attack on marsh faces, and feedbacks between vegetation and hydrodynamics.
Tidal channels deliver sediment to the vegetated subaerial marsh plain on high tides, which tends to increase the elevation of the marsh plain through time. Prior work suggests that marsh plains and channel networks develop simultaneously, moving toward an equilibrium condition where the net sediment flux through the channel network channels equals zero, and the transfer of sediment from channel to marsh platform balances sea level rise. Therefore, measurements of the concentration and flux of sediments through tidal channels represent a spatially integrated measure of marsh stability.
Recent work has highlighted the ephemeral nature of salt marshes, pointing out the balance between erosive forces and sediment supply. Wave attack on marsh faces is a primary erosive force, and causes marsh banks to slump, thereby liberating sediment from the marsh plain. Under low external sediment supply conditions, this leads to an overall landward migration of the marsh plain. We are exploring the connections between wave attack, marsh erosion, sediment supply, and ecosystem services through site-specific studies and larger scale syntheses of existing data.
Below are multimedia items associated with this project.
Below are publications associated with this project.
Dynamic interactions between coastal storms and salt marshes: A review
Spatially integrative metrics reveal hidden vulnerability of microtidal salt marshes
Balanced sediment fluxes in southern California’s Mediterranean-climate zone salt marshes
Inferring tidal wetland stability from channel sediment fluxes: observations and a conceptual model
Suspended sediment fluxes in a tidal wetland: Measurement, controlling factors, and error analysis
- Overview
Tidal wetlands are an important geomorphic and ecological feature of the coastal zone. Our projects deal with the physical forcings that affect wetland stability over event-to-annual timescales, including wave attack, sediment supply, and sea-level rise.
Tidal wetland complexes are geomorphic features composed of vegetated marsh plain, intertidal flats, and tidal channels. The stability of a tidal wetland complex is a function of interconnected biogeomorphic and physical processes. We are primarily studying the influence of sediment supply through tidal channels, wave attack on marsh faces, and feedbacks between vegetation and hydrodynamics.
Tidal channels deliver sediment to the vegetated subaerial marsh plain on high tides, which tends to increase the elevation of the marsh plain through time. Prior work suggests that marsh plains and channel networks develop simultaneously, moving toward an equilibrium condition where the net sediment flux through the channel network channels equals zero, and the transfer of sediment from channel to marsh platform balances sea level rise. Therefore, measurements of the concentration and flux of sediments through tidal channels represent a spatially integrated measure of marsh stability.
Recent work has highlighted the ephemeral nature of salt marshes, pointing out the balance between erosive forces and sediment supply. Wave attack on marsh faces is a primary erosive force, and causes marsh banks to slump, thereby liberating sediment from the marsh plain. Under low external sediment supply conditions, this leads to an overall landward migration of the marsh plain. We are exploring the connections between wave attack, marsh erosion, sediment supply, and ecosystem services through site-specific studies and larger scale syntheses of existing data.
- Multimedia
Below are multimedia items associated with this project.
- Publications
Below are publications associated with this project.
Dynamic interactions between coastal storms and salt marshes: A review
This manuscript reviews the progresses made in the understanding of the dynamic interactions between coastal storms and salt marshes, including the dissipation of extreme water levels and wind waves across marsh surfaces, the geomorphic impact of storms on salt marshes, the preservation of hurricanes signals and deposits into the sedimentary records, and the importance of storms for the long termSpatially integrative metrics reveal hidden vulnerability of microtidal salt marshes
Salt marshes are valued for their ecosystem services, and their vulnerability is typically assessed through biotic and abiotic measurements at individual points on the landscape. However, lateral erosion can lead to rapid marsh loss as marshes build vertically. Marsh sediment budgets represent a spatially integrated measure of competing constructive and destructive forces: a sediment surplus may rBalanced sediment fluxes in southern California’s Mediterranean-climate zone salt marshes
Salt marsh elevation and geomorphic stability depends on mineral sedimentation. Many Mediterranean-climate salt marshes along southern California, USA coast import sediment during El Niño storm events, but sediment fluxes and mechanisms during dry weather are potentially important for marsh stability. We calculated tidal creek sediment fluxes within a highly modified, sediment-starved, 1.5-km2 salInferring tidal wetland stability from channel sediment fluxes: observations and a conceptual model
Anthropogenic and climatic forces have modified the geomorphology of tidal wetlands over a range of timescales. Changes in land use, sediment supply, river flow, storminess, and sea level alter the layout of tidal channels, intertidal flats, and marsh plains; these elements define wetland complexes. Diagnostically, measurements of net sediment fluxes through tidal channels are high-temporal resoluSuspended sediment fluxes in a tidal wetland: Measurement, controlling factors, and error analysis
Suspended sediment fluxes to and from tidal wetlands are of increasing concern because of habitat restoration efforts, wetland sustainability as sea level rises, and potential contaminant accumulation. We measured water and sediment fluxes through two channels on Browns Island, at the landward end of San Francisco Bay, United States, to determine the factors that control sediment fluxes on and off