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Ecosystems Restoration and Sustainability: Wetland Ecosystems



Krauss, K.W., McKee, K.L., and Hester, M.W., 2012, Water use characteristics of black mangrove (Avicennia germinans) communities along an ecotone with marsh at a northern geographical limit: Ecohydrology,




Snedden, G.A., 2011, Salinity and current velocity structure in the Houma Navigation Canal (HNC) [abs.], p. 65, IN, McKay, M. and Nides, J., eds., 2012, Proceedings: Twenty-sixth Gulf of Mexico information transfer meeting, March 2011, New Orleans, Louisiana, OCS Study BOEM 2012-107, 349 p.,

Saltwater intrusion can occur through a variety of processes, including wind-driven estuary-shelf exchanges, baroclinic exchanges brought about by horizontal density gradients, and dispersive processes such as tidal diffusion. Understanding these processes is important to accurately anticipate the effects that future actions and circumstances such as channel deepening, lock installation, altering freshwater inflows, increasing vessel traffic, and sea level rise may have on salt transport in estuarine settings. One such setting is the Houma Navigation Canal (HNC), which serves as a major conduit for salt to the marshes that surround it.


Snedden, G.A., Cable, J.E., Swarzenski, C., and Swenson, E., 2007, Sediment discharge into a subsiding Louisiana deltaic estuary through a Mississippi River diversion: Estuarine, Coastal and Shelf Science, v. 71, n. 1-2, p. 181-193,

Wetlands of the Mississippi River deltaic plain in southeast Louisiana have been hydrologically isolated from the Mississippi River by containment levees for nearly a century. The ensuing lack of fluvial sediment inputs, combined with natural submergence processes, has contributed to high coastal land loss rates. Controlled river diversions have since been constructed to reconnect the marshes of the deltaic plain with the river. This study examines the impact of a pulsed diversion management plan on sediment discharge into the Breton Sound estuary, in which duplicate diversions lasting two weeks each were conducted in the spring of 2002 and 2003.


Structural and Functional Characteristics of Mangrove Swamps (Doyle, Dr. Ken W. Krauss, Dr. Karen McKee, Dr. Beth Middleton)




Salt marsh-mangrove interactions in Australasia and the Americas (Dr. Ken W. Krauss, Dr. Karen McKee)




Relation Between Plant Community Structure and Function and the Effectiveness of Wetland Restoration Efforts (Dr. Rebecca J. Howard)




Effects of Marsh Impoundment and Management on the Plant Growing Environment of Louisiana's Deltaic Wetlands (Dr. Rebecca J. Howard)




Native Plants for Effective Coastal Wetland Restoration (Dr. Rebecca Howard)




Water Use Efficiency in Coastal Marsh Plants Transitioning to Mangrove in Ten Thousand Islands National Wildlife Refuge (Dr. Rebecca J. Howard, Dr. Ken W. Krauss)




Investigating Seasonal Patterns on Water Use of Vegetation along a Marsh-Marsh Ecotone in the Northern Everglades (Dr. Sharon M.L. Ewe, Dr. Ken W. Krauss)




Influence of Salinity, Tidal Amplitude and Hydroperiod on Herbaceous Marsh Vegetation Composition in Coastal Louisiana (Dr. Gregg Snedden)




Linking Hydrologic Characteristics to Plant Community Structure in the Ten Thousand Islands Region of the Florida Everglades (Dr. Rebecca J. Howard)




Relationships between Relative Marsh Elevation and Primary Productivity (Kari Cretini, Dr. Gregg Snedden, Dr. Gregory D. Steyer)




Flood Pulsing Dynamics and Disturbance in Natural and Restored Wetlands (Dr. Beth A. Middleton)




Coastal Marsh Dieback (Brown Marsh) Bibliography

Sudden marsh dieback events occur periodically in coastal marshes from the Northern Gulf of Mexico to Maine. One of the most severe events occurred in 2000, where over 100,000 ha of salt marsh were impacted throughout Louisiana’s Mississippi River Delta Plain. In 2009, Louisiana experienced another episode of large-scale coastal dieback that rivaled the peak dieback conditions from earlier in the decade. The cause of sudden marsh dieback is still under debate but may be cyclical depending on interactive climate conditions, sea level anomalies, and other biotic factors. NWRC scientists engage in field and laboratory studies to contribute our best understanding of possible causal mechanisms and management implications of sudden marsh dieback on long-term marsh resiliency and vulnerability to climate change.



Physiological Ecology and Ecohydrology (Dr. Ken W. Krauss)

The form, function, and productivity of wetland communities are influenced strongly by the hydrologic regime of an area. Wetland ecosystems persist by depending upon surpluses of rainfall, evapotranspiration, soil moisture, and frequency and amplitude of water level fluctuations. Wetland vegetation can also influence ecosystem water budgeting through conservative water- and carbon-use strategies.

For example, scientists studying the physiological ecology of the Palmyra Atoll, a U.S. territory located in the Pacific Ocean, have found that sea-level rise, rainfall variability, and introduced plants are important factors driving changes on low-lying atolls. The National Wetlands Research Center is investigating whether root-zone competition for fresh water is an important factor allowing non-native coconut palms to expand into native Pisonia grandis forests. Palmyra is critical to researchers because it offers scientists an opportunity to study how undisturbed ecological communities are structured and function. In 2001, Palmyra's tidal lands, submerged lands, and surrounding waters were designated as a National Wildlife Refuge by the Department of the Interior to preserve the natural character of fish, wildlife, plants, coral reef communities, and other resources.

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