This project assesses the physical controls of sediment and material exchange between wetlands and estuarine environments along the northern Gulf of Mexico (Grand Bay Alabama/Mississippi and Vermilion Bay, Louisiana) and the Atlantic coast (Chincoteague Bay, Virginia/Maryland).
A coastal system is an integrated and complex set of environments inter-related and inter-connected through physical and ecological processes and associated feedbacks. The Sea-level and Storms Impacts on Estuarine Environments and Shorelines (SSIEES) Project investigates the role extreme events (hurricanes, floods, and strong frontal systems) and sea-level change have on material exchange between marshes and adjacent estuarine water bodies along the northern Gulf of Mexico and the Atlantic coast including Grand Bay Alabama/Mississippi, Vermilion Bay, Louisiana, and Chincoteague Bay, Virginia/Maryland.
Project Goals
- Advance the understanding of sediment exchange and transport within the estuary and the adjacent estuarine shoreline environments.
- Address the short-term and long-term implications of storm- and sea level-related processes on the evolution of the estuarine system.
Project Objectives
- Quantify sedimentation rates and sediment source to the estuary proper as well as the adjacent shoreline environments.
- Use sediment texture and bathymetric change to evaluate areas of the estuary that act as sinks (short-term vs long-term) or sources of sediment to the coastal ocean.
- Quantify decadal to centennial scale change in shoreline position and interior vegetative coverage.
Approach
- Extend and analyze spatial and temporal datasets to identify and quantify physical processes affecting all estuarine environments.
- Integrate field measurement of accretion and subsidence with a multi-decadal scale remote sensing analysis to extend discrete physical process interpretations over a broader spatial domain.
The SSIEES Project will evaluate wetland-estuarine material exchange using the following project structure, which can be readily linked back to the prior stated objectives:
Research Tasks
Evaluate the sediment storage and mobility in the estuary/bay/lagoon environment
The focus of this task is to examine the role that marsh and shoreline erosion contribute to the sediment budgets of the adjacent open-water estuarine system. Sediments derived from marsh shoreline erosion generally have higher organic matter content than sediments derived from the erosion of barrier islands or delivered by rivers. Understanding the sediment budget in these estuarine environments provides a comprehensive perspective of what factors drive the estuary health and integrity.
Objectives
- Map bathymetry and sub-bottom characteristics for coastal embayments and compare with historical data to understand bay-scale infilling.
- Quantify sediment characteristics and identify bulk sediment provenance to quantify the contribution of marsh sediments to the estuary proper.
- Quantify sedimentation rates derived from shallow cores distributed throughout the bay.
Methodology
- Conduct single-beam and/or swath bathymetry surveys of the bay.
- Collect grab samples to characterize the modern surficial sediments.
- Collect shallow cores (~50 cm) to determine recent environmental change.
- Assess bay sedimentation rates using a combination of radionuclides and bathymetric data.
Assess and quantify dominant physical depositional and erosive processes in estuarine-shoreline environments
The goal of this task is to quantify physical and biogeochemical controls on sediment accretion and erosion in estuarine marsh-wetlands around the northern Gulf of Mexico and the Atlantic coast. Achievement of this goal will provide ground-truth data to compare with estimates of areal changes assessed through remote sensing techniques as well as establish a model of wetland response to episodic events such as hurricanes or persistent drivers like sea-level. While current statewide coastal monitoring networks provide critical information, especially with respect to recent (last 5 years) marsh accretion in restoration areas, these investigations have not addressed long-term, historical accretion rates for much of the northern Gulf of Mexico.
Objectives
- Identify the dominate modes of sedimentation and erosion within a particular estuarine marsh-wetland type and evaluate significance relative to proximity to sediment source.
- Develop multi-proxy technique (microfossils, geochemical markers, and chronology) to understand how natural and anthropogenic activities in estuarine marsh-wetlands have altered dominate modes of sedimentation, and
- Develop a quantitative model to evaluate how certain estuarine marsh-wetlands respond (deposition or erosion) to episodic events (storms, brown marsh episodes).
Methodology
- Marsh coring proximal to monitoring sites where infrastructure includes meteorological (MET) stations, sediment elevation tables (SETs), and water level gauges.
- Use lead-210 and cesium-137 to quantify historic marsh accretion rates.
- Use basic sediment properties and grain size to sediment provenance.
- Use foraminiferal assemblages and geochemical tracers to evaluate environmental change.
- Link core based chronologic events with remote sensing datasets to aid in scaling point measurements (cores) from local- to regional-scale.
Conduct a chronological geospatial assessment and quantification of episodic impacts in wetland environments
The goal of this task is to map, characterize, and quantify cumulative episodic event-driven loss in northern Gulf of Mexico coastal wetlands over the past century using available remotely sensed data. Achievement of this goal will provide spatially explicit estimates of wetland loss/gain caused by episodic large-scale drivers versus changes from persistent drivers such as sea-level rise and cumulative cold-front passages (Barras, 2003; Barras, 2006; Barras, 2009).
Objectives
- Compile historical imagery and remote sensing datasets to quantify hurricane-induced wetland losses in northern Gulf of Mexico (Grand Bay Alabama/Mississippi; Vermilion Bay, Louisiana) and Atlantic coast (Chincoteague Bay, Virginia/Maryland).
- Relate observed features to storm characteristics, morphological type (Morton and Barras, 2011), and potential cumulative event effects to understand how landscape setting influences feature evolution.
- Evaluate episodic impacts on wetlands with contrasting long-term trajectories (e.g. accreting, stable, and degrading).
- Integrate 2-dimensional episodic wetland change information with core data to assist in the development of a quantitative wetland response model.
Methodology
- Digitize areal extent of wetland losses caused by both historical and recent hurricanes as bracketed by areal imagery.
- Identify episodic wetland loss data using the storm-impact feature classification scheme developed by Morton and Barras (2011).
- Compile and analyze cumulative event history to quantify episodic event driven wetland loss over time within the study area.
Below are data or web applications associated with this project.
Subbottom and Sidescan Sonar Data Acquired in 2015 From Grand Bay, Mississippi and Alabama
Below are publications associated with this project.
Single-beam bathymetry data collected in 2015 from Grand Bay, Alabama-Mississippi
A seasonal comparison of surface sediment characteristics in Chincoteague Bay, Maryland and Virginia, USA
Sedimentological and radiochemical characteristics of marsh deposits from Assateague Island and the adjacent vicinity, Maryland and Virginia, following Hurricane Sandy
Biological and geochemical data along Indian Point, Vermilion Bay, Louisiana
Archive of single-beam bathymetry data collected from select areas in Weeks Bay and Weeks Bayou, southwest Louisiana, January 2013
An evaluation of temporal changes in sediment accumulation and impacts on carbon burial in Mobile Bay, Alabama, USA
Radioisotopic data of sediment collected in Mobile and Bon Secour Bays, Alabama
Benthic foraminiferal census data from Mobile Bay, Alabama--counts of surface samples and box cores
Over 100 years of environmental change recorded by foraminifers and sediments in a large Gulf of Mexico estuary, Mobile Bay, AL, USA
Holocene evolution of Apalachicola Bay, Florida
Natural radium and radon tracers to quantify water exchange and movement in reservoirs
Influence of sea level rise on iron diagenesis in an east Florida subterranean estuary
- Overview
This project assesses the physical controls of sediment and material exchange between wetlands and estuarine environments along the northern Gulf of Mexico (Grand Bay Alabama/Mississippi and Vermilion Bay, Louisiana) and the Atlantic coast (Chincoteague Bay, Virginia/Maryland).
Estuary photos from Vermillion Bay, Louisiana. (Credit: Chris G. Smith, USGS. Public domain.) A coastal system is an integrated and complex set of environments inter-related and inter-connected through physical and ecological processes and associated feedbacks. The Sea-level and Storms Impacts on Estuarine Environments and Shorelines (SSIEES) Project investigates the role extreme events (hurricanes, floods, and strong frontal systems) and sea-level change have on material exchange between marshes and adjacent estuarine water bodies along the northern Gulf of Mexico and the Atlantic coast including Grand Bay Alabama/Mississippi, Vermilion Bay, Louisiana, and Chincoteague Bay, Virginia/Maryland.
Project Goals
- Advance the understanding of sediment exchange and transport within the estuary and the adjacent estuarine shoreline environments.
- Address the short-term and long-term implications of storm- and sea level-related processes on the evolution of the estuarine system.
Project Objectives
- Quantify sedimentation rates and sediment source to the estuary proper as well as the adjacent shoreline environments.
- Use sediment texture and bathymetric change to evaluate areas of the estuary that act as sinks (short-term vs long-term) or sources of sediment to the coastal ocean.
- Quantify decadal to centennial scale change in shoreline position and interior vegetative coverage.
Approach
- Extend and analyze spatial and temporal datasets to identify and quantify physical processes affecting all estuarine environments.
- Integrate field measurement of accretion and subsidence with a multi-decadal scale remote sensing analysis to extend discrete physical process interpretations over a broader spatial domain.
The SSIEES Project will evaluate wetland-estuarine material exchange using the following project structure, which can be readily linked back to the prior stated objectives:
Research Tasks
Evaluate the sediment storage and mobility in the estuary/bay/lagoon environment
Example of the activities utilized to evaluate sediment storage in the open water estuarine system, initially bathymetry and subbottom profiling surveys are conducted to evaluate sediment sinks within the estuary that are then followed by targeted coring and subsequent analyses of core material. (Public domain.) The focus of this task is to examine the role that marsh and shoreline erosion contribute to the sediment budgets of the adjacent open-water estuarine system. Sediments derived from marsh shoreline erosion generally have higher organic matter content than sediments derived from the erosion of barrier islands or delivered by rivers. Understanding the sediment budget in these estuarine environments provides a comprehensive perspective of what factors drive the estuary health and integrity.
Objectives
- Map bathymetry and sub-bottom characteristics for coastal embayments and compare with historical data to understand bay-scale infilling.
- Quantify sediment characteristics and identify bulk sediment provenance to quantify the contribution of marsh sediments to the estuary proper.
- Quantify sedimentation rates derived from shallow cores distributed throughout the bay.
Methodology
- Conduct single-beam and/or swath bathymetry surveys of the bay.
- Collect grab samples to characterize the modern surficial sediments.
- Collect shallow cores (~50 cm) to determine recent environmental change.
- Assess bay sedimentation rates using a combination of radionuclides and bathymetric data.
Assess and quantify dominant physical depositional and erosive processes in estuarine-shoreline environments
The goal of this task is to quantify physical and biogeochemical controls on sediment accretion and erosion in estuarine marsh-wetlands around the northern Gulf of Mexico and the Atlantic coast. Achievement of this goal will provide ground-truth data to compare with estimates of areal changes assessed through remote sensing techniques as well as establish a model of wetland response to episodic events such as hurricanes or persistent drivers like sea-level. While current statewide coastal monitoring networks provide critical information, especially with respect to recent (last 5 years) marsh accretion in restoration areas, these investigations have not addressed long-term, historical accretion rates for much of the northern Gulf of Mexico.
Example of wetland sediment sampling using a peat auger. (Public domain.) Objectives
- Identify the dominate modes of sedimentation and erosion within a particular estuarine marsh-wetland type and evaluate significance relative to proximity to sediment source.
- Develop multi-proxy technique (microfossils, geochemical markers, and chronology) to understand how natural and anthropogenic activities in estuarine marsh-wetlands have altered dominate modes of sedimentation, and
- Develop a quantitative model to evaluate how certain estuarine marsh-wetlands respond (deposition or erosion) to episodic events (storms, brown marsh episodes).
Methodology
- Marsh coring proximal to monitoring sites where infrastructure includes meteorological (MET) stations, sediment elevation tables (SETs), and water level gauges.
- Use lead-210 and cesium-137 to quantify historic marsh accretion rates.
- Use basic sediment properties and grain size to sediment provenance.
- Use foraminiferal assemblages and geochemical tracers to evaluate environmental change.
- Link core based chronologic events with remote sensing datasets to aid in scaling point measurements (cores) from local- to regional-scale.
Conduct a chronological geospatial assessment and quantification of episodic impacts in wetland environments
A simple comparison between the 1848 U.S. Coastal and Geodetic Survey T-Sheet #243 map (left) and the 2006 U.S. Department of Agriculture (USDA) National Agriculture Imagery Product (right) for the Grand Bay region located at the border of Mississippi and Alabama. A digitized surface/shoreline from the 1848 survey is presented in red and overlain onto the National Agriculture Imagery Program (NAIP) image to highlight the extensive estuarine marsh-wetland area loss. (Public domain.) The goal of this task is to map, characterize, and quantify cumulative episodic event-driven loss in northern Gulf of Mexico coastal wetlands over the past century using available remotely sensed data. Achievement of this goal will provide spatially explicit estimates of wetland loss/gain caused by episodic large-scale drivers versus changes from persistent drivers such as sea-level rise and cumulative cold-front passages (Barras, 2003; Barras, 2006; Barras, 2009).
Objectives
- Compile historical imagery and remote sensing datasets to quantify hurricane-induced wetland losses in northern Gulf of Mexico (Grand Bay Alabama/Mississippi; Vermilion Bay, Louisiana) and Atlantic coast (Chincoteague Bay, Virginia/Maryland).
- Relate observed features to storm characteristics, morphological type (Morton and Barras, 2011), and potential cumulative event effects to understand how landscape setting influences feature evolution.
- Evaluate episodic impacts on wetlands with contrasting long-term trajectories (e.g. accreting, stable, and degrading).
- Integrate 2-dimensional episodic wetland change information with core data to assist in the development of a quantitative wetland response model.
Methodology
- Digitize areal extent of wetland losses caused by both historical and recent hurricanes as bracketed by areal imagery.
- Identify episodic wetland loss data using the storm-impact feature classification scheme developed by Morton and Barras (2011).
- Compile and analyze cumulative event history to quantify episodic event driven wetland loss over time within the study area.
- Data
Below are data or web applications associated with this project.
Subbottom and Sidescan Sonar Data Acquired in 2015 From Grand Bay, Mississippi and Alabama
Grand Bay Alabama and Mississippi were surveyed between May and June 2015, using an Edgetech chirp 424 subbottom profiler and a Klein 3900 sidescan sonar. The objective was to characterize the geologic framework of recent estuarine sediment accumulation in the bay. This data release includes the raw chirp subbottom Society of Exploration Geophysicists (SEG Y) data files, sidescan data files in eXt - Publications
Below are publications associated with this project.
Filter Total Items: 13Single-beam bathymetry data collected in 2015 from Grand Bay, Alabama-Mississippi
As part of the Sea-level and Storm Impacts on Estuarine Environments and Shorelines (SSIEES) project, scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted a single-beam bathymetry survey within the estuarine, open-bay, and tidal creek environments of Grand Bay, Alabama-Mississippi, from May to June 2015. The goal of the SSIEES project is to aAuthorsNancy T. DeWitt, Chelsea A. Stalk, Christopher G. Smith, Stanley D. Locker, Jake J. Fredericks, Terrence A. McCloskey, Cathryn J. WheatonA seasonal comparison of surface sediment characteristics in Chincoteague Bay, Maryland and Virginia, USA
Scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of surficial sediments from Chincoteague Bay and Tom's Cove, between Assateague Island and the Delmarva Peninsula in late March/early April 2014 and October 2014. The sampling efforts were part of a larger U.S. Geological Survey study to assess the effects of storm events onAuthorsAlisha M. Ellis, Marci E. Marot, Cathryn J. Wheaton, Julie Bernier, Christopher G. SmithSedimentological and radiochemical characteristics of marsh deposits from Assateague Island and the adjacent vicinity, Maryland and Virginia, following Hurricane Sandy
The effect of tropical and extratropical cyclones on coastal wetlands and marshes is highly variable and depends on a number of climatic, geologic, and physical variables. The impacts of storms can be either positive or negative with respect to the wetland and marsh ecosystems. Small to moderate amounts of inorganic sediment added to the marsh surface during storms or other events help to abate prAuthorsChristopher G. Smith, Marci E. Marot, Alisha M. Ellis, Cathryn J. Wheaton, Julie Bernier, C. Scott AdamsBiological and geochemical data along Indian Point, Vermilion Bay, Louisiana
Scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center collected shallow sediment cores and surface samples from a coastal salt marsh environment next to Vermilion Bay in southwest Louisiana in January 2013. The sampling was part of a larger USGS study to gather data for assessing environmental changes over the past 150 years. The objective of the study was toAuthorsKathryn A. Richwine, Marci E. Marot, Christopher G. Smith, Lisa E. Osterman, C. Scott AdamsArchive of single-beam bathymetry data collected from select areas in Weeks Bay and Weeks Bayou, southwest Louisiana, January 2013
A team of scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, collected 92 line-kilometers of dual-frequency single-beam bathymetry data in the tidal creeks, bayous, and coastal areas near Weeks Bay, southwest Louisiana. Limited bathymetry data exist for these tidally and meteorologically influenced shallow-water estuarine environments. In order to reduceAuthorsNancy T. DeWitt, Christopher D. Reich, Christopher G. Smith, Billy J. ReynoldsAn evaluation of temporal changes in sediment accumulation and impacts on carbon burial in Mobile Bay, Alabama, USA
The estuarine environment can serve as either a source or sink of carbon relative to the coastal ocean carbon budget. A variety of time-dependent processes such as sedimentation, carbon supply, and productivity dictate how estuarine systems operate, and Mobile Bay is a system that has experienced both natural and anthropogenic perturbations that influenced depositional processes and carbon cyclingAuthorsChristopher G. Smith, Lisa E. OstermanRadioisotopic data of sediment collected in Mobile and Bon Secour Bays, Alabama
The focus of this study was to determine the extent of natural and (or) anthropogenic impacts on the sedimentary records of Mobile and Bon Secour Bays, Alabama during the last 150 years. These bays are unique in that anthropogenic activities are generally widespread and span both the eastern and western shorelines. However, there is a clear distinction in the types of human development and infrastAuthorsMarci E. Marot, Christopher G. SmithBenthic foraminiferal census data from Mobile Bay, Alabama--counts of surface samples and box cores
A study was undertaken in order to understand recent environmental change in Mobile Bay, Alabama. For this study a series of surface sediment and box core samples was collected. The surface benthic foraminiferal data provide the modern baseline conditions of the bay and can be used as a reference for changing paleoenvironmental parameters recorded in the box cores. The 14 sampling locations were cAuthorsKathryn A. Richwine, Lisa E. OstermanOver 100 years of environmental change recorded by foraminifers and sediments in a large Gulf of Mexico estuary, Mobile Bay, AL, USA
The marine microfauna of Mobile Bay has been profoundly influenced by the development and expansion of the primary shipping channel over the last ˜100 years. Foraminifers and sediments from seven box cores with excess lead-210 chronology document that channel dredging and spoil disposal have altered circulation, reduced estuarine mixing, changed sedimentation patterns, and caused a faunal turnoverAuthorsLisa E. Osterman, Christopher G. SmithHolocene evolution of Apalachicola Bay, Florida
A program of geophysical mapping and vibracoring was conducted in 2007 to better understand the geologic evolution of Apalachicola Bay and its response to sea-level rise. A detailed geologic history could help better understand how this bay may respond to both short-term (for example, storm surge) and long-term sea-level rise. The results of this study were published (Osterman and others, 2009) asAuthorsLisa E. Osterman, David C. TwichellNatural radium and radon tracers to quantify water exchange and movement in reservoirs
Radon and radium isotopes are routinely used to quantify exchange rates between different hydrologic reservoirs. Since their recognition as oceanic tracers in the 1960s, both radon and radium have been used to examine processes such as air-sea exchange, deep oceanic mixing, benthic inputs, and many others. Recently, the application of radon-222 and the radium-quartet (223,224,226,228Ra) as coastalAuthorsChristopher G. SmithInfluence of sea level rise on iron diagenesis in an east Florida subterranean estuary
Subterranean estuary occupies the transition zone between hypoxic fresh groundwater and oxic seawater, and between terrestrial and marine sediment deposits. Consequently, we hypothesize, in a subterranean estuary, biogeochemical reactions of Fe respond to submarine groundwater discharge (SGD) and sea level rise. Porewater and sediment samples were collected across a 30-m wide freshwater dischargeAuthorsM. Roy, J.B. Martin, J. Cherrier, J.E. Cable, C.G. Smith