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Focus on Estuaries and Coastal Wetlands
Estuaries and wetlands provide a critical defense against storms and sea-level rise while providing economically valuable services. How well they protect coastal communities and host diverse ecosystems is largely a function of their shape (morphology), which is controlled by factors such as sediment movement and biological feedbacks.
Measuring parameters such as water velocity, salinity, sediment concentration, dissolved oxygen and other constituents in watersheds, tidal wetlands, estuaries, and coasts is critical for evaluating the socioeconomic and ecological function of those regions. Technological advances have made it possible to autonomously measure these parameters over timescales of weeks to months. These measurements are necessary to evaluate three-dimensional numerical models that can represent the spatial and temporal complexity of these parameters. Once the models adequately represent relevant aspects of the physical system, they can be used to evaluate possible future scenarios including sea-level rise, streamflow changes, land-use modifications, and geomorphic evolution.
Estuarine processes, hazards, and ecosystems describes several interdisciplinary projects that aim to quantify and understand estuarine processes through observations and numerical modeling. Both the spatial and temporal scales of these mechanisms are important, and therefore require modern instrumentation and state-of-the-art hydrodynamic models. These projects are led from the U.S....
Increased loadings of nutrients to estuaries have altered ecosystem function by encouraging growth of phytoplankton and macroalgae while inducing large swings in dissolved oxygen and threatening the sustainability of seagrass meadows. We are measuring and modeling these processes to understand the future trajectory of estuarine ecosystems.
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.
Extreme tides and coastal storms transfer high water levels to estuaries through natural and managed entrances. The size of the transfer depends on the duration of the event and the geomorphology of the estuary. We use observational data and modeling scenarios to understand and spatially map this transfer at our study sites.
Changes to the geomorphic structure of estuaries impact hydrodynamics, ecosystem function, and navigation. We are implementing new methods of observing and modeling these changes using innovative field and computational approaches.
We are developing new routines within the COAWST model framework to represent coupled bio-physical processes in estuarine and coastal regions. These include routines for marsh vulnerability to waves, estuarine biogeochemistry, and feedbacks between aquatic vegetation and hydrodynamics.