I. Data Set Descriptors A. Title: null. 2023. Wrack classification data based on UAV imagery from Dean Creek on Sapelo Island, GA. Georgia Coastal Ecosystems LTER Data Catalog (data set GIS-GCET-2308; /data/GIS-GCET-2308) B. Accession Number: GIS-GCET-2308 C. Description 1. Originator(s): null 2. Abstract: We used a DJI Matrice 210 UAV with a MicaSense Altum to collect a total of 20 images from January 2020 - December 2021 in a the Dean Creek marsh on Sapelo Island, GA. Wrack was classified using a principal component analysis. Wrack patches under 1 m2 were excluded from analyses. Wrack classifications were converted to polygon and point data where each point represents a 5 cm x 5 cm pixel. Those files were then used to analyze wrack characteristics, their relation to environmental drivers, and landscape based patterns. For both polygon and point data, we used the National Elevation Dataset (https://gdg.sc.egov.usda.gov/Catalog/ProductDescription/NED.html) to determine the elevation of each wrack patch. Creeks and shorelines were digitized and used to determine each wrack patches' distance to water. We calculated the frequency of wrack deposition at each point by adding together the number of images where that pixel was classified as wrack over the course of the study. Polygon data were related to tide height from a NOAA tidal station data product (Ft. Pulaski, Station 8670870; https://tidesandcurrents.noaa.gov) and wind speed and wind direction from the Marsh Landing weather station (downloaded data for the SAPMLMET met station from: https://cdmo.baruch.sc.edu/) to evaluate the relationship of wrack to environmental drivers. 3. Study Type: Graduate Thesis Study 4. Study Themes: Geospatial Analysis 5. LTER Core Areas: Disturbance Patterns 6. Georeferences: geographic coordinates as data columns 7. Submission Date: Aug 23, 2023 D. Keywords: disturbance, Disturbance Patterns, GCE, GCE6, Georgia, Georgia Coastal Ecosystems, LTER, mapping, remote sensing, salt marshes, Sapelo Island, 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: DC_drone -- Dean Creek drone imagery area, Sapelo Island, Georgia, USA Coordinates: DC_drone -- NW: 081 17 03.90 W, 31 23 24.03 N NE: 081 16 43.39 W, 31 23 24.03 N SE: 081 16 43.39 W, 31 23 06.61 N SW: 081 17 03.90 W, 31 23 06.61 N b. Physiographic Region: DC_drone -- Barrier island c. Landform Components: DC_drone -- Intertidal salt marsh, sand beach, maritime forest d. Hydrographic Characteristics: DC_drone -- Site is near Dean Creek and is subject to 2-3m semi-diurnal tides e. Topographic Attributes: DC_drone -- Flat, with elevations ranging from 0-3m above mean low tide f. Geology, Lithology and Soils: DC_drone -- unspecified g. Vegetation Communities: DC_drone -- Vegetation is mostly short and tall Spartina alterniflora, with small amounts of Juncus and Borrichia. 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: The Dean Creek marsh one of the GCE study sites with ongoing, monthly UAV surveys. This study site also has ongoing research to track wrack disturbances and recovery in the field. We selected the study area to leverage existing field data and support ongoing research for the larger GCE disturbance project. The images selected were from the following dates (all times in UTC): 1/24/2020 - 20:10, 3/18/2020 - 14:06, 5/15/2020 - 13:40, 6/17/2020 - 14:20, 7/29/2020 - 14:42, 8/27/2020 - 13:55, 9/23/2020 - 13:30, 10/23/2020 - 14:00, 1/25/2021 - 14:05, 2/22/2021 - 14:50, 3/24/2021 - 14:18, 4/21/2021 - 14:15, 5/20/2021 - 14:00, 6/23/2021 - 19:00, 7/19/2021 - 14:10, 8/17/2021 - 13:45, 9/14/2021 - 14:30, 10/13/2021 - 14:15, 11/15/2021 - 14:45, 12/13/2021 - 15:00. b. Permanent Plots: No permanent plots were established for this study. c. Data Collection Duration and Frequency: All wrack over 1 m2 in the study site was surveyed for each UAV image available during the January 2020 - December 2021 time period. Wrack was determined through visual analysis of wrack images. Ground-truthing of classifications was conducted in September 2020 to validate classification accuracy. Beginning of Observations: Jan 01, 2020 End of Observations: Dec 31, 2021 3. Research Methods a. Field and Laboratory Methods: Method 1: Drone Data Acquisition and Pre-processing -- We acquired a total of 20 aerial images of the study site from January 2020 – December 2021. Eight images were acquired over the course of 2020, and 12 (monthly) images in 2021. We used a MicaSense Altum camera (MicaSense, Seattle, WA, USA) mounted on a DJI Matrice 210 UAV (DJI, Shenzhen, China). To minimize the effects of marsh inundation and sunglint, we collected data during morning low tides within 1-2 hours of solar noon. Data were collected at an altitude of 120 m (resulting in a ground sampling distance of ~ 5 cm), with 80% front and side overlap, at a camera angle of 90° (nadir), and with a parallel north and south flight pattern. Pix4D Capture (Pix4D S.A., Switzerland) and DJI Ground Station Pro (DJI, Shenzhen, China) software were both used for planning flight missions. Georectification and radiometric corrections were then conducted for all images using Pix4D Mapper software. Method 2: PCA Classification of Wrack -- We conducted a Principal Component Analysis (PCA) using all bands of the UAV images. Two out of five possible PCA components were selected based on their contrast between wrack and other features. We then set a threshold in the components to separate wrack from non-wrack features in a binary wrack map. A median 5 x 5 filter was used to eliminate salt and pepper noise. This file was then converted to polygons and points where wrack patches under 1 m2 were excluded from the data set. Method 3: Wrack Dynamics and Environmental Drivers -- We used the polygon file and extracted additional environmental information. The mean elevation of each wrack patch was acquired from the National Elevation Dataset (https://gdg.sc.egov.usda.gov/Catalog/ProductDescription/NED.html). We also calculated the distance to water for each wrack patch. Distance to water was determined by digitizing creeks and shorelines in the study area. The Near tool in ArcPro was then used to determine the Euclidean distance between a wrack patch and the nearest creek or shoreline. Tide height, wind speed, and wind direction data were calculated for the 30 days prior to each UAV image using data from a NOAA tidal station data (Ft. Pulaski, Station 8670870; https://tidesandcurrents.noaa.gov) and the Marsh Landing weather station (downloaded data for the SAPMLMET met station from: https://cdmo.baruch.sc.edu/). We calculated the correlation coefficients of each environmental variable and wrack characteristics (mean, median, standard deviation, kurtosis, and skewness of wrack patches’ elevation, distance to water, and patch area ). We then used linear regression for environmental characteristics that were significantly correlated with wrack characteristics to analyze the relationship. Method 4: Landscape Based Analyses -- The point file was used to assess spatial and temporal variation of wrack across the landscape. For each point, we calculated the number of images where that point was classified as wrack based on the PCA wrack classifications. Distance to water was determined by calculating the Euclidean distance of each point to the nearest creek or shoreline using the Near tool in ArcPro. Elevation was calculated from National Elevation Dataset. b. Protocols: Method 1: none Method 2: none Method 3: none Method 4: none c. Instrumentation: Method 1: DJI Matrice 210 Drone Manufacturer: DJI Matrice (Model: 210) MicaSense Altum Sensor Manufacturer: MicaSense (Model: Altum) Parameter: Blue band (Range: 475 nm center, 32 nm bandwidth) Parameter: Green band (Range: 560 nm center, 27 nm bandwidth) Parameter: near-IR band (Range: 842 nm center, 57 nm bandwidth) Parameter: Red band (Range: 668 nm center, 16 nm bandwidth) Parameter: Red edge band (Range: 717 nm center, 12 nm bandwidth) Method 2: DJI Matrice 210 Drone Manufacturer: DJI Matrice (Model: 210) MicaSense Altum Sensor Manufacturer: MicaSense (Model: Altum) Parameter: Blue band (Range: 475 nm center, 32 nm bandwidth) Parameter: Green band (Range: 560 nm center, 27 nm bandwidth) Parameter: near-IR band (Range: 842 nm center, 57 nm bandwidth) Parameter: Red band (Range: 668 nm center, 16 nm bandwidth) Parameter: Red edge band (Range: 717 nm center, 12 nm bandwidth) Method 3: none Method 4: none d. Taxonomy and Systematics: Method 1: not applicable Method 2: not applicable Method 3: not applicable Method 4: not applicable e. Speclies List: f. Permit History: Method 1: not applicable Method 2: not applicable Method 3: not applicable Method 4: not applicable 4. Project Personnel a. Personnel: 1: Tyler Lynn 2: Merryl Alber 3: Jacob Shalack 4: Deepak Mishra b. Affiliations: 1: University of Georgia 2: University of Georgia, Athens, Georgia 3: University of Georgia Marine Institute, Sapelo Island, Georgia 4: University of Georgia, Athens, Georgia III. Data Set Status and Accessibility A. Status 1. Latest Update: 30-Aug-2023 2. Latest Archive Date: 30-Aug-2023 3. Latest Metadata Update: 30-Aug-2023 4. Data Verification Status: Updated 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: Aug 23, 2023, Public: Aug 23, 2025 b. Citation: Data provided by the Georgia Coastal Ecosystems Long Term Ecological Research Project, supported by funds from NSF OCE 1832178 (data set GIS-GCET-2308) 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: GIS-GCET-2308_1_0.CSV 2. Size: 2001730 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 3.9.9b (06-Mar-2019) Data structure version: GCE Data Structure 1.1 (29-Mar-2001) Original data files processed: WrackPoints_pt1.txt (999999 records) WrackPoints_pt2.txt (1001731 records) Data processing history: 29-Aug-2023: new GCE Data Structure 1.1 created ('newstruct') 29-Aug-2023: 999999 rows imported from ASCII data file 'WrackPoints_pt1.txt' ('imp_ascii') 29-Aug-2023: 13 metadata fields in file header parsed ('parse_header') 29-Aug-2023: data structure validated ('gce_valid') 29-Aug-2023: 1001731 rows added at the bottom of the data set from '' ('datamerge') 29-Aug-2023: Q/C flagging criteria applied, 'flags' field updated ('dataflag') 29-Aug-2023: Name of column lon changed to longitude; Name of column lat changed to latitud ('ui_editor') 29-Aug-2023: updated 1 metadata fields in the Dataset section(s) ('addmeta') 29-Aug-2023: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 29-Aug-2023: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement section(s) ('addmeta') 30-Aug-2023: updated 1 metadata fields in the Dataset section(s) ('addmeta') 30-Aug-2023: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 30-Aug-2023: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement section(s) ('addmeta') 30-Aug-2023: manually edited data set metadata ('ui_editmetadata') 30-Aug-2023: updated 1 metadata fields in the Dataset section(s) ('addmeta') 30-Aug-2023: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 30-Aug-2023: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement section(s) ('addmeta') 30-Aug-2023: updated 1 metadata fields in the Dataset section(s) ('addmeta') 30-Aug-2023: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 30-Aug-2023: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement section(s) ('addmeta') 30-Aug-2023: updated 6 metadata fields in the Data section(s) ('addmeta') 30-Aug-2023: updated 15 metadata fields in the Status, Data sections to reflect attribute metadata ('updatecols') 30-Aug-2023: parsed and formatted metadata ('listmeta') B. Variable Information 1. Variable Name: column 1. grid_code column 2. water_dist column 3. elevation column 4. longitude column 5. latitude 2. Variable Definition: column 1. The number of images a pixel was classified as wrack. column 2. The distance of a pixel from the nearest creek or shoreline. column 3. NED elevation of the pixel relative to NAVD88. column 4. UTM easting of pixel in zone 17N. column 5. UTM northing of pixel in zone 17N. 3. Units of Measurement: column 1. count column 2. meters column 3. meters column 4. meters column 5. meters 4. Data Type a. Storage Type: column 1. integer column 2. floating-point column 3. floating-point column 4. floating-point column 5. floating-point b. Variable Codes: c. Numeric Range: column 1. 1 to 11 column 2. 0.00045708 to 167.1969 column 3. 1.1755e-38 to 1.4605 column 4. 473050.2891 to 473403.0891 column 5. 3472342.668 to 3472723.718 d. Missing Value Code: 5. Data Format a. Column Type: column 1. numerical column 2. numerical column 3. numerical column 4. numerical column 5. numerical b. Number of Columns: 5 c. Decimal Places: column 1. 0 column 2. 6 column 3. 6 column 4. 4 column 5. 3 6. Logical Variable Type: column 1. data (discrete) column 2. data (continuous) column 3. data (continuous) column 4. geographic coordinate (continuous) column 5. geographic coordinate (continuous) 7. Flagging Criteria: column 1. none column 2. none column 3. none column 4. none column 5. 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