Dr. Gregory Steyer is a wetland ecologist who serves as Gulf of Mexico regional science advisor for the USGS Southeast region. Greg received his B.S. from the University of Maryland in 1985, M.S. in 1988 from the University of Louisiana at Lafayette, and Ph.D. at Louisiana State University in the Department of Oceanography and Coastal Studies in 2008.
Greg's primary interest is developing ecological indicators, adaptive management approaches, and ecological and landscape models for use in natural resource decision support. For over 25 years, he has worked for State and Federal governments developing monitoring, modeling and research programs for the evaluation of wetland restoration projects and programs.
Greg has developed a comprehensive wetland monitoring network for the Coastal Wetlands Planning, Protection, and Restoration Act (CWPPRA) called the Coastwide Reference Monitoring System (http://www.lacoast.gov/crms2/Home.aspx), that allows evaluation of the effects of restoration and protection efforts at project, hydrologic basin and coastwide scales. Greg has also developed desktop ecological models for the Louisiana Coastal Area and Louisiana State Master Plan that project over 50 years how wetland vegetation communities and coastal geomorphology will change with and without restoration and protection efforts. His current research investigates the effects of disturbance events, primarily hurricanes, and sea-level rise on coastal landscape change and resilience.
Barrier islands protect mainland areas from storm surge, but can erode over time and require restoration. Ship Island, a barrier island off the coast of Mississippi, provides an example of this: the island was battered by Hurricane Camille in 1969 and split into two separate islands. As part of the Mississippi Coastal Improvements Program, the U.S. Army Corps of Engineers plans to use...
The Floristic Quality Index (FQI) has been used in many areas throughout the United State to assess the integrity of plant communities and restoration projects. Here, we summarize two tools that have been developed for monitoring sites in coastal Louisiana wetlands. The FQI was modified for herbaceous data collected in coastal Louisiana monitoring...
Dorney, John; Savage, Rick; Tiner, R.W.; Adamus, Paul; Cretini, Kari; Wood, William B.; Visser, Jenneke M.; Krauss, Ken W.; Sharp, Leigh Anne; Steyer, Gregory D.; Shaffer, Gary P.; Piazza, Sarai Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH) approach is being used...
Osland, Michael J.; Griffith, Kereen T.; Larriviere, Jack C.; Feher, Laura C.; Cahoon, Donald R.; Enwright, Nicholas M.; Oster, David A.; Tirpak, John M.; Woodrey, Mark S.; Collini, Renee C.; Baustian, Joseph J.; Breithaupt, Joshua L.; Cherry, Julia A; Conrad, Jeremy R.; Cormier, Nicole; Coronado-Molina, Carlos A.; Donoghue, Joseph F.; Graham, Sean A.; Harper, Jennifer W.; Hester, Mark W.; Howard, Rebecca J.; Krauss, Ken W.; Kroes, Daniel; Lane, Robert R.; McKee, Karen L.; Mendelssohn, Irving A.; Middleton, Beth A.; Moon, Jena A.; Piazza, Sarai; Rankin, Nicole M.; Sklar, Fred H.; Steyer, Gregory D.; Swanson, Kathleen M.; Swarzenski, Christopher M.; Vervaeke, William; Willis, Jonathan M; Van Wilson, K. Above- and belowground production in coastal wetlands are important contributors to carbon accumulation and ecosystem sustainability. As sea level rises, we can expect shifts to more salt-tolerant communities, which may alter these ecosystem functions and services. Although the direct influence of salinity on species-level primary production has...
Stagg, Camille L.; Schoolmaster, Donald R.; Piazza, Sarai C.; Snedden, Gregg; Steyer, Gregory D.; Fischenich, Craig J; McComas, Robert W. Soil bulk density (BD), soil organic matter (SOM) content, and a conversion factor between SOM and soil organic carbon (SOC) are often used in estimating SOC sequestration and storage. Spatial variability in BD, SOM, and the SOM–SOC conversion factor affects the ability to accurately estimate SOC sequestration, storage, and the benefits (e.g.,...
Wang, Hongqing; Piazza, Sarai C.; Sharp, Leigh A.; Stagg, Camille L.; Couvillion, Brady R.; Steyer, Gregory D.; McGinnis, Thomas E. Coastal ecosystem management typically relies on subjective interpretation of scientific understanding, with limited methods for explicitly incorporating process knowledge into decisions that must meet multiple, potentially competing stakeholder objectives. Conversely, the scientific community lacks methods for identifying which advancements in...
Dalyander, P. Soupy; Meyers, Michelle B.; Mattsson, Brady; Steyer, Gregory; Godsey, Elizabeth; McDonald, Justin; Byrnes, Mark R.; Ford, Mark Development of a comprehensive and stakeholder-driven Regional Sediment Management plan can provide the basis for long-term sustainable resource use and protection. This paper highlights three operational components that can positively influence sediment management at a regional scale, including (1) integration of an operational sediment budget, (...
Underwood, Steven G.; Khalil, Syed M.; Byrnes, Mark R.; Steyer, Gregory D.; Raynie, Richard C
Wetland sediment data were collected in 2009 and 2010 throughout the southwest Louisiana Chenier Plain as part of a pilot study to develop a diatom-based proxy for past wetland water chemistry and the identification of sediment deposits from tropical storms. The complete dataset includes forty-six surface sediment samples and nine sediment cores....
Smith, Kathryn E. L.; Flocks, James G.; Steyer, Gregory D.; Piazza, Sarai C. Large sediment diversions are proposed and expected to build new wetlands to alleviate the extensive wetland loss (5,000 km2) affecting coastal Louisiana during the last 78 years. Current assessment and prediction of the impacts of sediment diversions have focused on the capture and dispersal of both water and sediment on the adjacent river side...
Wang, Hongqing; Steyer, Gregory D.; Couvillion, Brady R.; John M. Rybczyk; Beck, Holly J.; William J. Sleavin; Ehab A. Meselhe; Mead A. Allison; Boustany, Ronald G.; Craig J. Fischenich; Victor H. Rivera-Monroy Normalized Difference Vegetation Index (NDVI) derived from MODerate-resolution Imaging Spectroradiometer (MODIS) satellite imagery and land/water assessments from Landsat Thematic Mapper (TM) imagery were used to quantify the extent and severity of damage and subsequent recovery after Hurricanes Katrina and Rita of 2005 within the vegetation...
Steyer, Gregory D.; Couvillion, Brady R.; Barras, John A. Coastal Louisiana is a dynamic and ever-changing landscape. From 1956 to 2010, over 3,734 km2 of Louisiana's coastal wetlands have been lost due to a combination of natural and human-induced activities. The resulting landscape constitutes a mosaic of conditions from highly deteriorated to relatively stable with intact landmasses. Understanding how...
Suir, Glenn M.; Evers, D. Elaine; Steyer, Gregory D.; Sasser, Charles E. Coastal eutrophication in the northern Gulf of Mexico (GOM) is the primary anthropogenic contributor to the largest zone of hypoxic bottom waters in North America. Although biologically mediated processes such as denitrification (Dn) are known to act as sinks for inorganic nitrogen, it is unknown what contribution denitrification makes to...
Rivera-Monroy, Victor H.; Branoff, Benjamin; Meselhe, Ehab; McCorquodale, Alex; Dortch, Mark; Steyer, Gregory D.; Visser, Jenneke; Wang, Hongqing Few landscape scale models have assessed the effects of coastal protection and restoration projects on wetland morphology while taking into account important uncertainties in environmental factors such as sea-level rise (SLR) and subsidence. In support of Louisiana's 2012 Coastal Master Plan, we developed a spatially explicit wetland morphology...
Couvillion, Brady R.; Steyer, Gregory D.; Wang, Hongqing; Beck, Holly J.; Rybczyk, John M.