I. Data Set Descriptors A. Title: Christopher B. Craft. 2023. Comparing vertical accretion, organic carbon (C) sequestration, and nitrogen burial between a natural, never diked tidal salt marsh and a hydrologically restored tidal salt marsh on Sapelo Island, Georgia.. Georgia Coastal Ecosystems LTER Data Catalog (data set HYD-GCED-2310; /data/HYD-GCED-2310) B. Accession Number: HYD-GCED-2310 C. Description 1. Originator(s): Name: Christopher B. Craft Address: Indiana University - School of Public and Environmental Affairs Room 408. MSB II. Bloomington, Indiana 47405 Country: USA Email: ccraft@indiana.edu 2. Abstract: Restoration of tidal marshes throughout the 20th century have attempted to bring back important functions of natural tidal systems. In this study, vertical accretion, organic carbon (C) sequestration, and nitrogen burial were compared between a natural, never diked tidal salt marsh and a hydrologically restored tidal salt marsh on Sapelo Island, Georgia to examine the impacts of restoration years later. On Sapelo Island there are two marshes near the University of Georgia Marine Institute, one of which is a natural marsh, and one of which is a restored marsh. The restored marsh had been diked in 1948, and the dike was breached, allowing for the marsh to be restored, in 1956. Soil cores were collected from both marshes, and the sediments were analysed for Nitrogen and Carbon concentrations and bulk density. This analysis was used to determine accretion rates for the two marshes as well as changes in the restored marsh since the dike was breached. Nitrogen burial, carbon sequestration, and soil accretion in the restored marsh as compared to the natural marsh were the focus of this study. 3. Study Type: Directed Study 4. Study Themes: Hydrography/Hydrology, Marsh Ecology 5. LTER Core Areas: Organic Matter 6. Georeferences: geographic coordinates as data columns 7. Submission Date: Oct 11, 2023 D. Keywords: accretion, carbon, carbon cycling, GCE, Georgia, Georgia Coastal Ecosystems, LTER, nitrogen cycling, Organic Matter, salt marshes, Sapelo Island, UGA, USA II. Research Origin Descriptors A. Overall Project Description 1. Project Title: Georgia Coastal Ecosystems LTER - IV 2. Principal Investigators: Name: Merryl Alber Address: Dept. of Marine Sciences University of Georgia Athens, Georgia 30602-3636 Country: USA Email: malber@uga.edu 3. Funding Period: Feb 01, 2019 to Jan 31, 2025 4. Objectives: The GCE-LTER project has four goals. 1) Track environmental and human drivers that can cause perturbations in our focal ecosystems. This will be accomplished this through continuing long-term measurements of climate, water chemistry, oceanic exchange, and human activities on the landscape. 2) Describe temporal and spatial variability in physical, chemical, geological and biological characteristics of the study system (coastal wetland complexes) and how they respond to external drivers. This will be accomplished through field monitoring in combination with remote sensing and modeling. 3) Characterize the ecological responses of intertidal marshes to disturbance. This will be accomplished by ongoing monitoring and experimental work to evaluate system responses to major perturbations in three key marsh habitats (changes in inundation and predator exclusion in Spartina-dominated salt marshes; increases in salinity in fresh marshes; changes in runoff in high marshes), by implementing standardized experimental disturbances along salinity and elevation gradients, and by tracking responses to natural disturbances. 4) Evaluate ecosystem properties at the landscape level (habitat distribution, net and gross primary production, C budgets) and assess the cumulative effects of disturbance on these properties. The project will also develop relationships between drivers and response variables, which can be used to predict the effects of future changes. This will be accomplished through a combination of data synthesis, remote sensing and modeling. 5. Abstract: The Georgia Coastal Ecosystems (GCE) Long Term Ecological Research (LTER) program, based at the University of Georgia Marine Institute on Sapelo Island, Georgia, was established in 2000 to study long-term change in coastal ecosystems. Estuaries (places where salt water from the ocean mixes with fresh water from the land) and their adjacent marshes provide food and refuge for fish, shellfish and birds; protect the shoreline from storms; help to keep the water clean; and store carbon. The GCE LTER researchers study marshes and estuaries to understand how these ecosystems function, to track how they change over time, and to predict how they might be affected by future changes in climate and human activities. They accomplish this by tracking the major factors that can cause long-term change in coastal areas (e.g. sea level, rainfall, upstream development), and measuring the effects of these factors on the study site. They also conduct focused studies to assess how key marsh habitats will respond to major changes expected in the future, including large-scale experiments to evaluate the effects of a) increases in the salinity of the water that floods freshwater marshes (mimicking drought and/or sea level rise), b) changes in water runoff from land into the upland marsh border (mimicking drought or upland development), and c) exclusion of larger organisms in the salt marsh (mimicking long-term declines in predators). During this award they will initiate additional studies to systematically evaluate how coastal wetlands respond to disturbances. Disturbances, or disruptions in the environment, are particularly important to understand in the context of long-term background changes such as increasing sea level, and GCE researchers are working to assess the cumulative effects of multiple disturbances on the landscape. The GCE education and outreach program works to share an understanding of coastal ecosystems with teachers and students, coastal managers, citizen scientist and the general public. 6. Funding Source: NSF OCE 1832178 B. Sub-project Description 1. Site Description a. Geographic Location: Sapelo -- Sapelo Island, Sapelo Island, Georgia Coordinates: Sapelo -- NW: 081 18 28.72 W, 31 32 10.93 N NE: 081 10 34.26 W, 31 32 10.93 N SE: 081 10 34.26 W, 31 22 48.54 N SW: 081 18 28.72 W, 31 22 48.54 N b. Physiographic Region: Sapelo -- unspecified c. Landform Components: Sapelo -- Barrier island d. Hydrographic Characteristics: Sapelo -- unspecified e. Topographic Attributes: Sapelo -- unspecified f. Geology, Lithology and Soils: Sapelo -- unspecified g. Vegetation Communities: Sapelo -- Salt marsh vegetation on the island exterior (dominated by Spartina alterniflora), transitioning to marsh meadow and maritime forest on the island interior h. History of Land Use and Disturbance: none recorded i. Climate: Climate summary for Sapelo Island, Georgia, based on NWS data from 1980-2010: Daily-aggregated Values: Mean (sample standard deviation) mean air temperature: 20.09°C (7.28°C) minimum air temperature: 15.02°C (7.96°C) maximum air temperature: 24.82°C (6.98°C) total precipitation: 3.26mm (10.3mm) Yearly-aggregated Daily Values: Mean (sample standard deviation) total precipitation (1980-2010): 1124mm (266mm) 2. Experimental or Sampling Design a. Design Characteristics: On Sapelo Island there are two marshes near the University of Georgia Marine Institute, one of which is a natural marsh, and one of which is a restored marsh. The restored marsh had been diked ion 1948, and the dike was breached, allowing for the marsh to be restored, in 1956. Soil cores were collected from both marshes. Nitrogen burial, carbon sequestration, and soil accretion in the restored marsh as compared to the natural marsh were the focus of this study. b. Permanent Plots: The first plot was a natural marsh, and the other was a restored marsh that had been diked in the past and restored once the dike was breached. The restored and never diked natural marsh are part of the Light- house Creek drainage and are 28.9 ha and 40.6 ha in size, respectively. Both are flooded twice daily by astronomical tides of 2.3 m on average and are dominated by a monoculture of Spartina alterniflora Loisel. Flooding of the marshes is almost exclusively by tidal inundation as there are no streams or ditches entering from the uplands. Marsh elevations are similar between sites, ranging from 0.82 to 0.91 m NAVD88 in the restored marsh and 0.79–0.93 m NAVD88 in the natural marsh. Annual measurements in medium height Spartina marshes of adjacent Dean Creek taken by the Georgia Coastal Ecosystems' Long Term Ecological Research program since 2000 were used to estimate above- ground biomass of our marshes. These values ranged from 262 g/m2 to 348 g/m2 c. Data Collection Duration and Frequency: Three soil cores of 8.5 cm in diameter and 60 cm in depth were collected from each central locations in each marsh. The cores were divided into 2 cm increments in the field before being sent to the lab for analysis. In the lab, bulk density, Nitrogen can Carbon were measured. Beginning of Observations: Jan 01, 2020 End of Observations: Nov 16, 2022 3. Research Methods a. Field and Laboratory Methods: Method 1: Soil sampling and lab analysis -- Three soil cores 8.5 cm in diameter by 60 cm deep were collected from each marsh. Cores were collected at mid-marsh locations where medium height Spartina grows. Cores were sectioned into 2 cm increments in the field, then transported to the lab where they were air dried and weighed for bulk density. Once dried, increments were ground, passed through a 2 mm mesh sieve, and analyzed for 137Cs, 210Pb, organic C and total N. Method 2: Bulk Density and CN analysis -- Prior to C analysis, subsamples were tested for the presence of carbonates by adding one drop of 0.1 mol L− 1 HCl and observing whether effervescence occurred. Samples containing carbonates were treated with 0.1 mol L− 1 HCl prior to C and N analysis. Carbon and N were analyzed using a Perkin-Elmer 2400 CHN analyzer (Perkin-Elmer, Waltham MA USA). Recovery of NIST standard 1632b (bituminous coal, 76.9% C, 1.56% N) yielded 92% for C and 94% for N (n = 10). Analysis of in-house soil standard (6.1% C, 0.37% N) recovered 101% for C and 102% for N (n = 10). Bulk density of each depth increment was calculated from the dry weight per unit volume (Blake and Hartje, 1986). All analyses were expressed on a dry weight basis by correcting for the moisture content of the soil, determined by weighing 1 g of subsoil before and after drying at 70 ◦C for 24 h. b. Protocols: Method 1: none Method 2: SALTEx - CHN Anaysis Organization: Georgia Coastal Ecosystems LTER Description: SALTEx protocol for CHN analysis of soils URL: http://gce-lter.marsci.uga.edu/public/app/resource_details.asp?id=769&version=1 Author: Christopher B. Craft (email: ccraft@indiana.edu) c. Instrumentation: Method 1: none Method 2: CHN Analyzer Manufacturer: Perkin Elmer (Model: 2400) Parameter: Organic Carbon Parameter: Total Nitrogen Electronic Balance Manufacturer: Ohaus (Model: ARC120) Parameter: mass (Readability: 0.01g, Range: 0.01g-3.1kg) d. Taxonomy and Systematics: Method 1: not applicable Method 2: not applicable e. Speclies List: f. Permit History: Method 1: not applicable Method 2: not applicable 4. Project Personnel a. Personnel: Christopher B. Craft b. Affiliations: Indiana University at Bloomington, Bloomington, Indiana III. Data Set Status and Accessibility A. Status 1. Latest Update: 22-Nov-2024 2. Latest Archive Date: 13-Nov-2024 3. Latest Metadata Update: 22-Nov-2024 4. Data Verification Status: New Submission B. Accessibility 1. Storage Location and Medium: Stored at GCE-LTER Data Management Office Dept. of Marine Sciences Univ. of Georgia Athens, GA 30602-3636 USA on media: electronic data download (WWW) or compact disk 2. Contact Person: Name: Adam Sapp Address: Department of Marine Sciences University of Georgia Athens, Georgia 30602 Country: USA Email: asapp@uga.edu 3. Copyright Restrictions: not copyrighted 4. Restrictions: This information is licensed under a Creative Commons Attribution 4.0 International License (see: https://creativecommons.org/licenses/by/4.0/). The consumer of these data ("Data User" herein) has an ethical obligation to cite it appropriately in any publication that results from its use. The Data User should realize that these data may be actively used by others for ongoing research and that coordination may be necessary to prevent duplicate publication. The Data User is urged to contact the authors of these data if any questions about methodology or results occur. Where appropriate, the Data User is encouraged to consider collaboration or co-authorship with the authors. The Data User should realize that misinterpretation of data may occur if used out of context of the original study. While substantial efforts are made to ensure the accuracy of data and associated documentation, complete accuracy of data sets cannot be guaranteed. All data are made available "as is." The Data User should be aware, however, that data are updated periodically and it is the responsibility of the Data User to check for new versions of the data. The data authors and the repository where these data were obtained shall not be liable for damages resulting from any use or misinterpretation of the data. a. Release Date: Affiliates: Oct 02, 2023, Public: Oct 02, 2025 b. Citation: Data provided by the Georgia Coastal Ecosystems Long Term Ecological Research Project, supported by funds from NSF OCE 1832178 (data set HYD-GCED-2310) c. Disclaimer: The user assumes all responsibility for errors in judgement based on interpretation of data and analyses presented in this data set. 5. Costs: free electronic data download via WWW, distribution on CD may be subject to nominal processing and handling fee IV. Data Structural Descriptors A. Data Set File 1. File Name: HYD-GCED-2310_2_0.CSV 2. Size: 166 records 3. File Format: ASCII text (comma-separated value format) 3a. Delimiters: single comma 4. Header Information: 5 lines of ASCII text 5. Alphanumeric Attributes: 6. Quality Control Flag Codes: Q = questionable value, I = invalid value, E = estimated value 7. Authentication Procedures: 8. Calculations: 9. Processing History: Software version: GCE Data Toolbox Version 3.9.10 (23-May-2022) Data structure version: GCE Data Structure 1.1 (29-Mar-2001) Original data file processed: Core_template.txt (166 records) Data processing history: 12-Nov-2024: new GCE Data Structure 1.1 created ('newstruct') 12-Nov-2024: 166 rows imported from ASCII data file 'Core_template.txt' ('imp_ascii') 12-Nov-2024: 13 metadata fields in file header parsed ('parse_header') 12-Nov-2024: data structure validated ('gce_valid') 12-Nov-2024: copied/reordered columns Site_ID, Core_ID, Latitude, Longitude, Depth_increment, Bulk_Density, Orcanic_C, Total_N, Depth_Increment, Carbon, Nitrogen, Carbon.Density and Nitrogen.Density ('copycols') 12-Nov-2024: updated 1 metadata fields in the Dataset section(s) ('addmeta') 12-Nov-2024: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 12-Nov-2024: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement section(s) ('addmeta') 12-Nov-2024: Description of column Depth_increment edited; Name of column Depth_increment changed to Depth_rang ('ui_editor') 13-Nov-2024: updated 1 metadata fields in the Dataset section(s) ('addmeta') 13-Nov-2024: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 13-Nov-2024: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement section(s) ('addmeta') 22-Nov-2024: Name of column Orcanic_C changed to Organic_ ('ui_editor') 22-Nov-2024: updated 6 metadata fields in the Data section(s) ('addmeta') 22-Nov-2024: updated 15 metadata fields in the Status, Data sections to reflect attribute metadata ('updatecols') 22-Nov-2024: parsed and formatted metadata ('listmeta') B. Variable Information 1. Variable Name: column 1. Site_ID column 2. Core_ID column 3. Latitude column 4. Longitude column 5. Depth_range column 6. Bulk_Density column 7. Organic_C column 8. Total_N column 9. Depth_Increment column 10. Carbon column 11. Nitrogen column 12. Carbon.Density column 13. Nitrogen.Density 2. Variable Definition: column 1. Natural or restored marsh column 2. Name of Core column 3. Latitude of core sample column 4. Longitude of core sample column 5. Depth range of core section column 6. Density of the soil column 7. Percent of carbon in the soil column 8. Percent of N in the soil column 9. Increment used to separate the soil core for analysis column 10. Carbon measured g/g column 11. Nitrogen measured g/g column 12. Total carbon mass per unit area column 13. Total nitrogen mass per unit area 3. Units of Measurement: column 1. none column 2. none column 3. degrees column 4. degrees column 5. cm column 6. g/cm3 column 7. percent column 8. percent column 9. cm column 10. g/g column 11. g/g column 12. g/m2 column 13. g/m2 4. Data Type a. Storage Type: column 1. string column 2. string column 3. floating-point column 4. floating-point column 5. string column 6. floating-point column 7. floating-point column 8. floating-point column 9. integer column 10. floating-point column 11. floating-point column 12. floating-point column 13. floating-point b. Variable Codes: Site_ID: R = Restored marsh, N = Natural Marsh Core_ID: R1 = restored marsh core 1, R2 = restored marsh core 2, R3 = restored marsh core 3, N1 = natural marsh core 1, N2 = natural marsh core 2, N3 = natural marsh core 3 c. Numeric Range: column 1. (none) column 2. (none) column 3. 31.3933 to 31.3997 column 4. -81.2844 to -81.2748 column 5. (none) column 6. 0.21157 to 2.0746 column 7. 0.46 to 10.171 column 8. 0.037 to 0.722 column 9. 2 to 2 column 10. 0.0046 to 0.10171 column 11. 0.00037 to 0.00722 column 12. 125.3402 to 1114.9921 column 13. 0.2738 to 104.2568 d. Missing Value Code: 5. Data Format a. Column Type: column 1. text column 2. text column 3. numerical column 4. numerical column 5. text column 6. numerical column 7. numerical column 8. numerical column 9. numerical column 10. numerical column 11. numerical column 12. numerical column 13. numerical b. Number of Columns: 13 c. Decimal Places: column 1. 0 column 2. 0 column 3. 6 column 4. 6 column 5. 0 column 6. 9 column 7. 3 column 8. 3 column 9. 0 column 10. 5 column 11. 5 column 12. 7 column 13. 4 6. Logical Variable Type: column 1. nominal (none) column 2. nominal (none) column 3. geographic coordinate (continuous) column 4. geographic coordinate (continuous) column 5. nominal (none) column 6. calculation (continuous) column 7. data (continuous) column 8. data (continuous) column 9. data (discrete) column 10. calculation (continuous) column 11. calculation (continuous) column 12. calculation (continuous) column 13. calculation (continuous) 7. Flagging Criteria: column 1. none column 2. none column 3. none column 4. none column 5. none column 6. none column 7. none column 8. none column 9. none column 10. none column 11. none column 12. none column 13. none C. Data Anomalies: V. Supplemental Descriptors A. Data Acquisition 1. Data Forms: 2. Form Location: 3. Data Entry Validation: B. Quality Assurance/Quality Control Procedures: C. Supplemental Materials: D. Computer Programs: E. Archival Practices: F. Publications: not specified G. History of Data Set Usage 1. Data Request History: not specified 2. Data Set Update History: none 3. Review History: none 4. Questions and Comments from Users: none