Location and elevation data for five sites in the coastal marsh at Grand Bay National Estuarine Research Reserve, Mississippi, from October 2020 to January 2023
To better understand sediment deposition in marsh environments, scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center (USGS-SPCMSC) selected five marsh study sites (Sites 5, 6, 7, 8, and 9) and four nearshore estuarine study sites (Sites 8S, 8D, 9S, 9D) along the Point Aux Chenes Bay shoreline of the Grand Bay National Estuarine Research Reserve (GNDNERR), Mississippi. This study builds on Smith and others (2020b) and includes datasets collected after the installation of a living shoreline (a subtidal sill [artificial reef]) that was completed in May 2021. Each marsh site consisted of five plots located along a transect perpendicular to the marsh-estuary shoreline at 5-meter (m) increments (5, 10, 15, 20, and 25 m from the shoreline). Each plot contained three to six net sedimentation tiles (NST) that were secured flush to the marsh surface using polyvinyl chloride (PVC) pipe. NST are an inexpensive and simple tool to assess short- and long-term deposition that can be deployed in highly dynamic environments without the compaction associated with traditional coring methods. The NST were deployed for three-month sampling periods, measuring sediment deposition from August 2021 to January 2023. Sediment deposited on the NST were processed to determine physical characteristics, such as deposition thickness, volume, wet weight/dry weight, grain size, and organic content (via loss-on-ignition [LOI]). For select sampling periods, ancillary data (water level, elevation, and vegetation) are also provided in this data release. The estuarine sites consisted of Site 8S (shallow; landward of the subtidal sill), 8D (deep; seaward side of the subtidal sill), as well as 9S and 9D (both sites established adjacent to 8S/8D and the subtidal sill). During select trips water parameters (e.g., waves, water level, and turbidity) were collected at each estuarine site to collect turbidity and wave data. Data presented in this data release were collected under three USGS Field Activities Numbers (FAN; one FAN per year) during thirteen sampling trips (alternate FAN; each sampling trip was assigned a unique alt FAN under the main FAN): 2021-320-FA (21CCT01, 21CCT03, 21CCT04, 21CCT05), 2022-302-FA (22CCT01, 22CCT02, 22CCT03, 22CCT04, 22CCT05, 22CCT06, 22CCT07, 22CCT08) and 2023-301-FA (23CCT01), however, every trip does not contain all data types. This data release also contains data for 2020-323-FA (20CCT02) that was collected as a special collection trip for Hurricane Delta. This data was collected before the subtidal sill was installed and is being published with this data release since pre-subtidal sill data was already published. Additional survey and data details are available from the U.S. Geological Survey Coastal and Marine Geoscience Data System (CMGDS) at,
https://cmgds.marine.usgs.gov/. Users can look up USGS FANs in the CMGDS by replacing the FAN in the following url:
https://cmgds.marine.usgs.gov/services/activity.php?fan=2022-302-FA. Data from a related NST study in the GNDNERR (Middle Bay and North Rigolets) can be found in Smith and others (2020a). Data collected from before the living shoreline (subtidal sill) installation can be found in Smith and others (2020b). For additional information on data processing and analysis, refer to the accompanying journal publication Smith and others (2025). Please read the full metadata for details on data collection, dataset variables, and data quality.
Data was collected through quarterly field visits. Each field visit was assigned a field activity number (FAN) and alternate FAN (alt-FAN) by the U.S Geological Survey (USGS). This publication contains data for field activities from: 1) 2020-323-FA (20CCT02; October 6-15 2020; pre- and post-Hurricane Delta), 2) 2021-320-FA (August 2021; 21CCT01, August 2021-September 2021; 21CCT03, September 2021-December 2021; 21CCT05), 3) 2022-302-FA (December 2021-February 2022; 22CCT01, February 2022-May 2022; 22CCT03, May 2022-August 2022; 22CCT05, August 2022-November 2022; 22CCT07), 4) 2023-301-FA (November 2022-January 2023; 23CCT01). NSTs were deployed on the start date and collected on the end date. Elevation data were collected and processed by the Grand Bay National Estuarine Research Reserve staff. This dataset, Grand_Bay_Elevation_Data.csv, was acquired in the North American Datum of 1983 State Plane Mississippi East Federal Information Processing Standard 2301 (NAD_1983_StatePlane_Mississippi_East_FIPS_2301) and transformed into the North American Datum of 1983 Universal Transverse Mercator Zone 16 North (NAD_1983_UTM_Zone_16N) for analysis and publishing.
