I. Data Set Descriptors A. Title: Steven C. Pennings. 2020. Long-term monitoring of seven high marsh plant mixtures on Sapelo Island GA. Georgia Coastal Ecosystems LTER Data Catalog (data set PLT-GCEM-2012; /data/PLT-GCEM-2012) B. Accession Number: PLT-GCEM-2012 C. Description 1. Originator(s): Name: Steven C. Pennings Address: Department of Biology and Biochemistry University of Houston Houston, Texas 77204-5513 Country: USA Email: scpennin@central.uh.edu 2. Abstract: We set up plots (1x2m) in 1996 in mixtures or on vegetation borders at three sites. We set up 16 plots for each of seven mixtures - Marsh Landing (Juncus-Meadow, Spartina-Meadow, and Spartina-Batis mixtures), Teal Boardwalk (Juncus-Spartina mixture) and Shell Hammock (Juncus-Spartina, Juncus-Meadow, and Spartina-Meadow mixtures). Half were watered with fresh water 3 times per week (W) and half were controls (C). Watering stopped in April 2000. Plots were monitored to document changes in plant community composition (percent cover) over time. 3. Study Type: Monitoring 4. Study Themes: Plant Ecology, Marsh Ecology 5. LTER Core Areas: Population Studies 6. Georeferences: none 7. Submission Date: Dec 07, 2020 D. Keywords: Amaranthaceae, Angiospermae, Asteraceae, Asterales, Asteranae, Bataceae, Batis maritima, Borrichia frutescens, Brassicales, Caryophyllales, Caryophyllanae, community composition, Distichlis spicata, Embryophyta, GCE, Georgia, Georgia Coastal Ecosystems, Juncaceae, Juncus effusus, Lilianae, LTER, Magnoliopsida, marine, marshes, plant community, plant cover, Plant Monitoring, Plantae, Poaceae, Poales, Population Studies, Rosanae, Salicornia bigelovii, Salicornia depressa, Sapelo Island, Spartina alterniflora, Spermatophytina, Sporobolus virginicus, Streptophyta, Tracheophyta, USA, Viridaeplantae, Viridiplantae 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: GCE6 -- Dean Creek, Sapelo Island, Georgia, USA ML -- Marsh Landing, Sapelo Island, Georgia, USA Shell_Hammock -- Shell_Hammock Coordinates: GCE6 -- NW: 081 17 58.28 W, 31 23 38.66 N NE: 081 15 51.76 W, 31 23 38.66 N SE: 081 15 51.76 W, 31 22 15.61 N SW: 081 17 58.28 W, 31 22 15.61 N ML -- NW: 081 17 50.80 W, 31 25 08.03 N NE: 081 17 40.58 W, 31 25 08.03 N SE: 081 17 40.58 W, 31 24 59.03 N SW: 081 17 50.80 W, 31 24 59.03 N Shell_Hammock -- 81 17 21.0 W, 31 24 03.0 N b. Physiographic Region: GCE6 -- Barrier island ML -- Barrier island Shell_Hammock -- unspecified c. Landform Components: GCE6 -- Intertidal salt marsh, sand beach, maritime forest ML -- Intertidal salt marsh Shell_Hammock -- unspecified d. Hydrographic Characteristics: GCE6 -- Site contains Dean Creek and borders Doboy Sound, and is subject to 2-3m semi-diurnal tides ML -- Site borders the Duplin River and is subject to 2-3m semi-diurnal tides Shell_Hammock -- unspecified e. Topographic Attributes: GCE6 -- Flat, with elevations ranging from 0-3m above mean low tide ML -- Flat, with elevations ranging from 0-3m above mean low tide Shell_Hammock -- unspecified f. Geology, Lithology and Soils: GCE6 -- unspecified ML -- unspecified Shell_Hammock -- unspecified g. Vegetation Communities: GCE6 -- Vegetation is mostly short and tall Spartina alterniflora, with small amounts of Juncus and Borrichia. ML -- Spartina alterniflora in low marsh, salt pan and salt-tolerant vegetation mixture in high marsh Shell_Hammock -- unspecified h. History of Land Use and Disturbance: GCE6 -- Oct 01, 2000: Permanent plots were established in two nominal marsh zones based on marsh structure -- creek zone and high marsh -- and eight plots were randomly located in each zone and marked with stakes Oct 01, 2001: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to catastrophic disturbance and replaced with new plots as indicated: zone 1, plot 3 (not replaced). Oct 19, 2002: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C1. The following plots were disturbed by wildlife (some have no shoots): M6, M7, M8 (snails). The following creekbank plots are on creekbank areas that are collapsing: C4, C5. No plots were replaced. Oct 17, 2003: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wildlife (some have no shoots): M8. The following creekbank plots are on creekbank areas that are collapsing: C5. The following plots were lost due to creekbank erosion or catastrophic wrack inundation and were replaced: C2, C4 (replaced with C12, C14). Oct 22, 2004: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C12, C23, C5, C6, C8. The following plots were disturbed by wildlife (some have no shoots): M8. No plots were lost due to creekbank erosion, and none were replaced. Oct 21, 2005: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C5, C12. The following plots were disturbed by wildlife: M8. No plots were lost due to creekbank erosion, and none were replaced. Oct 15, 2006: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C23, C6, C7 (C1, C23 have no plants). The following plots were disturbed by wildlife (some have no shoots): M8. The following creekbank plots are on creekbank areas that are collapsing: C12, C14, C5. No plots were lost and none were replaced. Oct 23, 2007: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C5, C14, C22. The following plots were disturbed by wrack or wildlife activity: C15, C16, C23, M8. No plots were replaced. Oct 26, 2008: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C24. The following plots were disturbed by wrack: C23. The following plots were distrurbed by wildlife (some may have no shoots): M8 (no shoots). The following plots are on creekbank areas that are collapsing: C22, C23. No plots were replaced. Oct 16, 2009: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C22, C23. No other plots were disturbed by wildlife or wrack, and none were replaced. Oct 20, 2010: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C6. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C32 (replaced with C42). No plots were disturbed by wildlife or are on creekbank areas that are collapsing. Oct 25, 2011: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots are located on sections of creek bank that are collapsing: C6, C33. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity and were replaced: C15 (now C25). Oct 15, 2012: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C6, C8, C33, C34. No plots were disturbed by creekbank erosion or wildlife, but no living plants were observed in C34 and M5 is now in an apparent die-back zone. Oct 16, 2013: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife: C15 (replaced with C25), C16 (replaced with C26), C8 (replaced with 18). Oct 18, 2014: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No disturbance was noted, and no plots were lost; however, plots C33, C34 and C26 were relabeled as C43, C44 and C36, resp. for unspecified reasons. Oct 15, 2015: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: M2. The following plots are on creekbank areas that are collapsing (slumping): C42, C36. The following plots were lost due to terminal slumping of the creekbank: C43, C44, C25 (replaced with C53, C54, C35). No plots were disturbed by wildlife. 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: Plots were set up at Marsh Landing (Juncus-Meadow, Spartina-Meadow, and Spartina-Batis mixtures), Teal Boardwalk (Juncus-Spartina mixture) and Shell Hammock (Juncus-Spartina, Juncus-Meadow, and Spartina-Meadow mixtures). Plots were 1x2 m. We set up 16 plots for each of seven mixtures. Half were watered with fresh water 3 times per week (W) and half were controls (C). Watering stopped in April 2000. We do not have GPS coordinates for plots yet, but I will obtain them in a coming year. b. Permanent Plots: Plots were 1x2 m, centered on vegetation borders (if present in 1996) or located in mixtures. c. Data Collection Duration and Frequency: Plots were monitored to document changes in plant community composition (percent cover) over time using a 0.5 x 0.5 m quadrat divided into 100 cells that was centered in the plot. Plants were recorded as present if present in each cell; thus, total cover could add up to > 100 percent. Cells were recorded as bare only if no plants occurred in them. Beginning of Observations: May 01, 1996 End of Observations: Jul 31, 2024 3. Research Methods a. Field and Laboratory Methods: Plot Monitoring -- Plots were monitored to document changes in plant community composition (percent cover) over time using a 0.5 x 0.5 m quadrat divided into 100 cells that was centered in the plot. Plants were recorded as present if present in each cell; thus, total cover could add up to > 100 percent. Cells were recorded as bare only if no plants occurred in them. b. Protocols: none c. Instrumentation: none d. Taxonomy and Systematics: not applicable e. Speclies List: f. Permit History: not applicable 4. Project Personnel a. Personnel: Steven C. Pennings b. Affiliations: University of Houston, Houston, Texas III. Data Set Status and Accessibility A. Status 1. Latest Update: 21-Aug-2024 2. Latest Archive Date: 15-Aug-2024 3. Latest Metadata Update: 21-Aug-2024 4. Data Verification Status: Reviewed by IM 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: Dec 07, 2020, Public: Dec 07, 2022 b. Citation: Data provided by the Georgia Coastal Ecosystems Long Term Ecological Research Project, supported by funds from NSF OCE 1832178 (data set PLT-GCEM-2012) 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: PLT-GCEM-2012_SB_ML_5_0.CSV 2. Size: 368 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: PLT-GCEM-2012_SB_ML.txt (368 records) Data processing history: 15-Aug-2024: new GCE Data Structure 1.1 created ('newstruct') 15-Aug-2024: 368 rows imported from ASCII data file 'PLT-GCEM-2012_SB_ML.txt' ('imp_ascii') 15-Aug-2024: 13 metadata fields in file header parsed ('parse_header') 15-Aug-2024: data structure validated ('gce_valid') 15-Aug-2024: Q/C flagging criteria applied, 'flags' field updated ('dataflag') 15-Aug-2024: automatically assigned study date metadata descriptors based on the range of date values in date/time columns (add_studydates) 15-Aug-2024: updated 1 metadata fields in the Dataset section(s) ('addmeta') 15-Aug-2024: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 15-Aug-2024: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement section(s) ('addmeta') 21-Aug-2024: Units of column Year changed from 'Year' to 'YYYY'; Units of column Month changed from 'Month' to 'MM ('ui_editor') 21-Aug-2024: updated 6 metadata fields in the Data section(s) ('addmeta') 21-Aug-2024: updated 15 metadata fields in the Status, Data sections to reflect attribute metadata ('updatecols') 21-Aug-2024: parsed and formatted metadata ('listmeta') B. Variable Information 1. Variable Name: column 1. Year column 2. Month column 3. Mixture column 4. Site column 5. Treatment column 6. Replicate column 7. Batis_Percent_Cover column 8. Distichlis_Percent_Cover column 9. Juncus_Percent_Cover column 10. Salicornia_Percent_Cover column 11. Spartina_Percent_Cover column 12. Bare_Percent_Cover 2. Variable Definition: column 1. Year sampled column 2. Month sampled column 3. Plant species mixture column 4. Site sampled column 5. Treatment column 6. Replicate column 7. Percent cover of Batis column 8. Percent cover of Distichlis column 9. Percent cover of Juncus column 10. Percent cover of Salicornia virginica=Sarcocornia sp. column 11. Percent cover of Spartina column 12. Percent cover bare ground 3. Units of Measurement: column 1. YYYY column 2. MM column 3. none column 4. none column 5. none column 6. none column 7. percent column 8. percent column 9. percent column 10. percent column 11. percent column 12. percent 4. Data Type a. Storage Type: column 1. integer column 2. integer column 3. string column 4. string column 5. string column 6. integer column 7. integer column 8. integer column 9. integer column 10. integer column 11. integer column 12. integer b. Variable Codes: Treatment: W=watered, C=control c. Numeric Range: column 1. 1996 to 2024 column 2. 1 to 9 column 3. (none) column 4. (none) column 5. (none) column 6. 1 to 8 column 7. 0 to 100 column 8. 0 to 36 column 9. 0 to 45 column 10. 0 to 100 column 11. 0 to 88 column 12. 0 to 96 d. Missing Value Code: 5. Data Format a. Column Type: column 1. numerical column 2. numerical column 3. text column 4. text column 5. text column 6. numerical column 7. numerical column 8. numerical column 9. numerical column 10. numerical column 11. numerical column 12. numerical b. Number of Columns: 12 c. Decimal Places: column 1. 0 column 2. 0 column 3. 0 column 4. 0 column 5. 0 column 6. 0 column 7. 0 column 8. 0 column 9. 0 column 10. 0 column 11. 0 column 12. 0 6. Logical Variable Type: column 1. datetime (discrete) column 2. datetime (discrete) column 3. free text (none) column 4. free text (none) column 5. coded value (none) column 6. ordinal (discrete) column 7. data (discrete) column 8. data (discrete) column 9. data (discrete) column 10. data (discrete) column 11. data (discrete) column 12. data (discrete) 7. Flagging Criteria: column 1. x<1996="I";x<1996="Q" column 2. x<1="I";x>12="I";x<1="Q";x>12="Q" column 3. none column 4. none column 5. none column 6. x<1="I";x>8="I";x<1="Q";x>8="Q" column 7. x<0="I";x>100="I";x<0="Q";x>100="Q" column 8. x<0="I";x>100="I";x<0="Q";x>100="Q" column 9. x<0="I";x>100="I";x<0="Q";x>100="Q" column 10. x<0="I";x>100="I";x<0="Q";x>100="Q" column 11. x<0="I";x>100="I";x<0="Q";x>100="Q" column 12. x<0="I";x>100="I";x<0="Q";x>100="Q" 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