I. Data Set Descriptors A. Title: Fan Li. 2017. Plant Responses to the GCE-LTER Seawater Addition Long Term Experiment (SALTEx) from 2013 to 2017. Georgia Coastal Ecosystems LTER Data Catalog (data set PLT-GCET-1703a; http://gce-lter.marsci.uga.edu/data/PLT-GCET-1703a) B. Accession Number: PLT-GCET-1703a C. Description 1. Originator(s): Name: Fan Li Address: Department of Biology and Biochemistry 369 Science and Research Bldg 2 Houston, Texas 77204-5001 Country: USA Email: lifan.uh@gmail.com 2. Abstract: This study was conducted in a tidal freshwater marsh (31°20’16” N, 81°27’52” W) on the Altamaha River, GA. Each plot was defined by a 2.5 m x 2.5 m polycon frame, inserted 12 cm into the soil. The frames had drain holes in the sides above the soil surface that were plugged when plots were watered but open otherwise to allow tidal exchange. The plots were randomly assigned to five treatments. Plots were monitored without imposing any treatments in 2013. Treatments started on April 14, 2014. Plots receive diluted saltwater (press and pulse of saline water treatments, n=6), freshwater (freshwater addition treatment, n=6), or no water additions (control with frame and control treatments, n=6 and 7, respectively). The press plots received additions of a mixture of seawater and fresh river water four times each week. Pulse plots received the same mixture but only for 8 weeks in September and October. The freshwater treatment plots received additions of fresh river water four times each week. To document treatment effects on the plant community, we measured stem height, photosynthesis, and percent cover of plants, and blocking of light by the vegetation. We used the same 0.75 m x 0.75 m subplot inside each plot for plant measurements, and took the measurements 3 – 6 times during each growing season from 2013 to 2017. We measured height of all stems of Zizaniopsis miliacea and Persicaria hydropiperoides, and all leaves of Pontederia cordata. In each plot, we chose the tallest individual of those three species and measured their photosynthetic rates using LCi photosynthesis System (ADC BioScientific Ltd, Hoddesdon, UK). Around the same dates, we also visually estimated the percent cover of Ludwigia repens, Persicaria hydropiperoides, Pontederia cordata, and Zizaniopsis miliacea in the entire 2.5 m x 2.5 m plot. We summed the stem heights by species as a first approximation of species biomass. We measured the photosynthetically active radiation (PAR) above top and underneath (10 cm above the soil) the plant canopy in each plot using a Sunscan Canopy Analysis System (AT Delta-T Devices Cambridge England) 4-6 times during each growing season from 2014 to 2017. We report the proportion of light penetrating the canopy. 3. Study Type: Graduate Thesis Study 4. Study Themes: Plant Ecology 5. LTER Core Areas: Disturbance Patterns, Primary Production 6. Georeferences: none 7. Submission Date: Mar 01, 2017 D. Keywords: Angiospermae, Caryophyllales, Caryophyllanae, Commelinales, disturbance, Disturbance Patterns, Embryophyta, GCE, Georgia, Georgia Coastal Ecosystems, irradiance, Lilianae, LTER, Ludwigia, Magnoliopsida, percent cover, Persicaria, Persicaria hydropiperoides, Plantae, plants, Poaceae, Poales, Polygonaceae, Pontederia, Pontederia cordata, Pontederiaceae, press, Primary Production, pulse, salinity, SALTEx, Sapelo Island, Scirpus, Spermatophytina, Streptophyta, Tracheophyta, Typha, USA, Viridaeplantae, Viridiplantae, Zizaniopsis, Zizaniopsis miliacea II. Research Origin Descriptors A. Overall Project Description 1. Project Title: Georgia Coastal Ecosystems LTER Project III 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: Nov 01, 2012 to Nov 01, 2018 4. Objectives: The research proposed for GCE-III is designed to address how variations in salinity and inundation, driven by climate change and anthropogenic factors, affect biotic and ecosystem responses at different spatial and temporal scales, and to predict the consequences of these changes for habitat provisioning and carbon (C) sequestration across the coastal landscape. 5. Abstract: The Georgia Coastal Ecosystems (GCE) LTER is located along three adjacent sounds on the Atlantic coast and includes both intertidal marshes and estuaries. Long-term drivers of climate change, sea level rise and human alterations of the landscape will cause transitions in dominant habitat types (state changes) within the GCE domain by changing the amounts and patterns of water delivery across the landscape. These changes in water delivery can be conceptualized as presses and pulses in river inflow, local runoff, groundwater input, and tidal inundation, which will in turn manifest themselves as changes in salinity and inundation patterns in the domain. The research proposed for GCE-III is designed to address how variations in salinity and inundation, driven by climate change and anthropogenic factors, affect biotic and ecosystem responses at different spatial and temporal scales, and to predict the consequences of these changes for habitat provisioning and carbon (C) sequestration across the coastal landscape. The goals are to: 1) Track long-term changes in climate and human actions in the watershed and adjacent uplands, and evaluate the effects of these drivers on domain boundary conditions. 2) Describe temporal and spatial variability in physical, chemical, geological and biological, and to evaluate how they are affected by variations in river inflow and other boundary conditions. 3) Characterize the responses of three dominant habitats in the domain to pulses and presses in salinity and inundation. 4) Describe patterns of habitat provisioning and C sequestration and export in the GCE domain, and to evaluate how these might be affected by changes in salinity and inundation. These efforts will be synthesized into a synoptic understanding of both biotic and ecosystem responses to variations in salinity and inundation driven by climate change and human activities, which will be used to assess thresholds between habitats and the potential for state changes in the domain. 6. Funding Source: NSF OCE 1237140 B. Sub-project Description 1. Site Description a. Geographic Location: SALTEx -- SALTEx Research Site, Champney Island, Georgia, USA Coordinates: SALTEx -- NW: 081 28 01.91 W, 31 20 23.40 N NE: 081 27 58.28 W, 31 20 23.40 N SE: 081 27 58.28 W, 31 20 20.23 N SW: 081 28 01.91 W, 31 20 20.23 N b. Physiographic Region: SALTEx -- unspecified c. Landform Components: SALTEx -- unspecified d. Hydrographic Characteristics: SALTEx -- unspecified e. Topographic Attributes: SALTEx -- unspecified f. Geology, Lithology and Soils: SALTEx -- unspecified g. Vegetation Communities: SALTEx -- Zizaniopsis, Spartina cynosuroides 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: Study 1: Allometry -- A field experiment in tidal freshwater marsh with press and pulse of saline water, freshwater addition, cotrol and control with frame treatments. Study 2: Cover -- A field experiment in tidal freshwater marsh with press and pulse of saline water, freshwater addition, cotrol and control with frame treatments. Study 3: Height -- A field experiment in tidal freshwater marsh with press and pulse of saline water, freshwater addition, cotrol and control with frame treatments. Study 4: Photosynthesis -- A field experiment in tidal freshwater marsh with press and pulse of saline water, freshwater addition, cotrol and control with frame treatments. Study 5: PAR -- A field experiment in tidal freshwater marsh with press and pulse of saline water, freshwater addition, cotrol and control with frame treatments. Study 6: Transplants -- A field experiment in tidal freshwater marsh with press and pulse of saline water, freshwater addition, cotrol and control with frame treatments. b. Permanent Plots: Study 1: Long-term plots were established in a tidal freshwater marsh (31°20’16” N, 81°27’52” W) on the Altamaha River, GA. Study 2: Long-term plots were established in a tidal freshwater marsh (31°20’16” N, 81°27’52” W) on the Altamaha River, GA. Study 3: Long-term plots were established in a tidal freshwater marsh (31°20’16” N, 81°27’52” W) on the Altamaha River, GA. Study 4: Long-term plots were established in a tidal freshwater marsh (31°20’16” N, 81°27’52” W) on the Altamaha River, GA. Study 5: Long-term plots were established in a tidal freshwater marsh (31°20’16” N, 81°27’52” W) on the Altamaha River, GA. Study 6: Long-term plots were established in a tidal freshwater marsh (31°20’16” N, 81°27’52” W) on the Altamaha River, GA. c. Data Collection Duration and Frequency: Study 1: Shoot height of Zizaniopsis miliacea and Persicaria hydropiperoides, and leaf height of Pontederia cordata were measured on the following dates: 6/1/2013, 7/15/2013, 8/11/2013, 3/24/2014, 5/20/2014, 6/5/2014, 7/7/2014, 8/1/2014, 10/18/2014, 3/16/2015, 5/23/2015, 6/29/2015, 7/20/2015, 8/3/2015, 10/19/2015, 3/15/2016, 6/27/2016, 7/13/2016, 8/2/2016, 10/28/2016 Study 2: Percent cover of Ludwigia peploides, Zizaniopsis miliacea, Pontederia cordata and Persicaria hydropiperoides was measured on the following dates: 6/1/2013, 7/15/2013, 8/11/2013, 3/24/2014, 5/29/2014, 6/24/2014, 7/31/2014, 10/14/2014, 3/16/2015, 5/23/2015, 6/25/2015, 7/20/2015, 8/3/2015, 10/19/2015, 3/16/2016, 6/28/2016, 7/13/2016, 8/2/2016, 10/28/2016, 6/15/2017, 7/7/2017, 8/1/2017, 10/17/2017. Percent cover of Scirpus validus (not present before 2016) was measured on 6/28/2016, 7/13/2016, 8/2/2016, 10/28/2016, 6/15/2017, 7/7/2017, 8/1/2017, 10/17/2017. Percent cover of Typha latifolia (not present before 2016) was measured on 6/28/2016, 7/13/2016, 8/2/2016, 6/15/2017, 7/7/2017, 8/1/2017, 10/17/2017. Study 3: Shoot height of Zizaniopsis miliacea and Persicaria hydropiperoides, and leaf height of Pontederia cordata were measured on the following dates: 6/1/2013, 7/15/2013, 8/11/2013, 3/24/2014, 5/20/2014, 6/5/2014, 7/7/2014, 8/1/2014, 10/18/2014, 3/16/2015, 5/23/2015, 6/29/2015, 7/20/2015, 8/3/2015, 10/19/2015, 3/15/2016, 6/27/2016, 7/13/2016, 8/2/2016, 10/28/2016, 6/15/2017, 7/7/2017, 8/1/2017, 10/17/2017 Study 4: A field experiment in tidal freshwater marsh with press and pulse of saline water, freshwater addition, cotrol and control with frame treatments. Study 5: Levels of photosynthetically active radiation (PAR) at each treatment was measured on the following dates: 3/26/2014, 5/20/2014, 6/5/2014, 7/7/2014, 8/1/2014, 10/14/2014, 3/16/2015, 5/22/2015, 6/29/2015, 10/19/2015, 3/15/2016, 6/27/2016, 7/13/2016, 8/2/2016, 11/15/2016, 10/17/2017 Study 6: not specified Beginning of Observations: Study 1: Jun 01, 2013 Study 2: Jun 01, 2013 Study 3: Jun 01, 2013 Study 4: Jun 18, 2013 Study 5: Mar 26, 2014 Study 6: Mar 07, 2017 End of Observations: Study 1: Oct 28, 2018 Study 2: Oct 17, 2017 Study 3: Oct 17, 2017 Study 4: Jul 14, 2016 Study 5: Oct 17, 2017 Study 6: Oct 15, 2017 3. Research Methods a. Field and Laboratory Methods: Method 1: Cover -- Percent cover was estimated visually by the same person. Method 2: Height -- Individual stem height was measured from the soil surface to the top green tip of each plant stem by ruler. Method 3: PAR -- We measured the photosynthetically active radiation (PAR) above top and underneath (10 cm above the soil) the plant canopy in each plot. Two above-canopy measurements were taken on each sampling day, one before the under-canopy measurements, one after. In 2017, we began measuring PAR above the canopy before each replicate measurement in the plots Method 4: Photosynthesis -- In each plot, we chose the tallest individual of Persicaria hydropiperoides, Pontederia cordata, and Zizaniopsis miliacea, and measured their photosynthetic rates Method 5: Transplants -- Because the experimental site was in the middle of an extensive tidal fresh marsh and physically isolated from brackish marshes, which were several km downstream, brackish marsh plants were essentially unable to recruit naturally to the experiment due to distance. We therefore transplanted two species of brackish marsh plants into the plots in 2017 as phytometers, or indicator transplants, to quantify how well they would perform if they had been able to recruit, with the expectation that they would do well in the saline treatments. We collected culms of Juncus roemerianus and Schoenoplectus sp. (likely Schoenoplectus americanus) from a brackish marsh ~5 km downstream of the study site (GCE site 8, Latitude 31.3126, Longitude -81.4209) on March 7, 2017, watered them with freshwater for three days to minimize transplant shock, and planted a single culm of each species into each plot on March 10, 2017. We collected individual culms at least 1 m apart to minimize the likelihood of collecting genetically identical individuals. When transplanted, J. roemerianus culms had ~10 leaves and Schoenoplectus sp. culms had ~2 shoots. Schoenoplectus sp. transplants grew quickly in some treatments, so we harvested them on July 25, 2017 to prevent them from becoming so abundant that they might affect conditions in the plots. J. roemerianus transplants grew slowly, and we waited until October 15, 2017 to harvest them. We excavated the transplants, dried above- and below-ground biomass at 60o for 3 days, and weighed it. Method 6: Allometry -- In July 2016, we collected 50 Z. miliacea individuals (50 cm – 235 cm), 54 P. hydropiperoides individuals (30 cm – 123 cm), and 95 P. cordata leaves (30 cm – 120 cm) from a marsh adjacent to the study site. The heights of the stems or leaves were measured on site, and then the plant material was dried at 60 °C to constant mass. We used these data to create allometric relationships between biomass and height for these species. b. Protocols: Method 1: none Method 2: none Method 3: none Method 4: none Method 5: none Method 6: none c. Instrumentation: Method 1: none Method 2: none Method 3: SunScan Canopy Analysis System Manufacturer: Delta-T Devices (Model: SS1-UM-1.05) Parameter: PAR intensity (Accuracy: 10%, Readability: 0.3 mmol/m^2/s, Range: 0-2500 mmol/m^2/s) SunScan Canopy Analysis System, Delta-T Devices Ltd. Method 4: LCi portable infrared gas analyzer Manufacturer: ADC Bioscientific Ltd. (Model: Lci) Parameter: Leaf-level photosynthetic rate LCi portable infrared gas analyzer, ADC BioScientific Ltd, Hoddesdon, UK Method 5: none Method 6: none d. Taxonomy and Systematics: Method 1: USDA plant classification Method 2: USDA plant classification Method 3: USDA plant classification Method 4: USDA plant classification Method 5: not applicable Method 6: not applicable e. Speclies List: f. Permit History: Method 1: University of Georgia Marine Institute collecting permits Method 2: University of Georgia Marine Institute collecting permits Method 3: University of Georgia Marine Institute collecting permits Method 4: University of Georgia Marine Institute collecting permits Method 5: not applicable Method 6: not applicable 4. Project Personnel a. Personnel: 1: Fan Li 2: Steven C. Pennings b. Affiliations: 1: University of Houston, Houston, Texas 2: University of Houston, Houston, Texas III. Data Set Status and Accessibility A. Status 1. Latest Update: 25-Feb-2022 2. Latest Archive Date: 25-Feb-2022 3. Latest Metadata Update: 25-Feb-2022 4. Data Verification Status: Reviewed by GCE-LTER 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: Wade M. Sheldon, Jr. Address: 130 Marine Sciences Marine Sciences Building Athens, Georgia 30602-3636 Country: USA Email: sheldon@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: Mar 01, 2017, Public: Mar 01, 2017 b. Citation: Data provided by the Georgia Coastal Ecosystems Long Term Ecological Research Project, supported by funds from NSF OCE 1237140 (data set PLT-GCET-1703a) 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-GCET-1703a_Height_3_0.CSV 2. Size: 42892 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: 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 file processed: Fan_Li_SALTEX_Height.txt (42892 records) Data processing history: 25-Feb-2022: new GCE Data Structure 1.1 created ('newstruct') 25-Feb-2022: 42892 rows imported from ASCII data file 'Fan_Li_SALTEX_Height.txt' ('imp_ascii') 25-Feb-2022: 82 metadata fields in file header parsed ('parse_header') 25-Feb-2022: data structure validated ('gce_valid') 25-Feb-2022: Q/C flagging criteria applied, 'flags' field updated ('dataflag') 25-Feb-2022: automatically assigned study date metadata descriptors based on the range of date values in date/time columns (add_studydates) 25-Feb-2022: 2872 values in 'Treatment' were updated with new values ('trim_textcols') 25-Feb-2022: Q/C flagging criteria applied for column(s) Treatment, 'flags' field updated ('dataflag') 25-Feb-2022: updated 1 metadata fields in the Dataset sections ('addmeta') 25-Feb-2022: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 25-Feb-2022: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement sections ('addmeta') 25-Feb-2022: updated 1 metadata fields in the Dataset sections ('addmeta') 25-Feb-2022: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 25-Feb-2022: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement sections ('addmeta') 25-Feb-2022: updated 6 metadata fields in the Data sections ('addmeta') 25-Feb-2022: updated 15 metadata fields in the Status, Data sections to reflect attribute metadata ('updatecols') 25-Feb-2022: parsed and formatted metadata ('listmeta') B. Variable Information 1. Variable Name: column 1. Date column 2. Treatment column 3. Plot_Replicate column 4. Stem_Number column 5. Height column 6. Species 2. Variable Definition: column 1. Date of measurement column 2. Treatment name column 3. Replicate of the treatment plot (additional plot was added for Control with frame in May 2015) column 4. sequential stem number column 5. Plant height measured by ruler column 6. Plant species 3. Units of Measurement: column 1. mm/dd/yyyy column 2. none column 3. none column 4. none column 5. cm column 6. none 4. Data Type a. Storage Type: column 1. string column 2. string column 3. integer column 4. integer column 5. integer column 6. string b. Variable Codes: c. Numeric Range: column 1. (none) column 2. (none) column 3. 1 to 7 column 4. 1 to 88 column 5. 0 to 295 column 6. (none) d. Missing Value Code: 5. Data Format a. Column Type: column 1. text column 2. text column 3. numerical column 4. numerical column 5. numerical column 6. text b. Number of Columns: 6 c. Decimal Places: column 1. 0 column 2. 0 column 3. 0 column 4. 0 column 5. 0 column 6. 0 6. Logical Variable Type: column 1. datetime (none) column 2. free text (none) column 3. nominal (discrete) column 4. ordinal (discrete) column 5. data (discrete) column 6. data (none) 7. Flagging Criteria: column 1. none column 2. none column 3. x<1="I";x>7="I";x<1="Q";x>7="Q" column 4. x<1="I";x>100="I";x<1="Q";x>100="Q" column 5. x<0="I";x>500="I";x<0="Q";x>500="Q" column 6. none C. Data Anomalies: V. Supplemental Descriptors A. Data Acquisition 1. Data Forms: paper log sheets 2. Form Location: Pennings Lab, Dept. of Biology and Biochemistry, University of Houston, Houston, TX 3. Data Entry Validation: B. Quality Assurance/Quality Control Procedures: C. Supplemental Materials: D. Computer Programs: Microsoft Excel 2010 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