https://doi.org/10.5061/dryad.kprr4xhf1

Description of the data and file structure

This Readme file was generated on 2024-09-17 by Oshini Fernando and Lawrence Flanagan

GENERAL INFORMATION

1. Title of Dataset: Frank Lake Ecosystem Flux & Met data for 2022 and 2023

2. Author Information:

W. Oshini K. Fernando*, Samuel G. Woodman*, Stewart B. Rood*, Lawrence B. Flanagan*^

*Department of Biological Sciences, University of Lethbridge, 4401 University Drive W., Lethbridge, Alberta T1K 3M4, Canada

 ^Corresponding author (E-mail: larry.flanagan@uleth.ca)

3. Data of Data Collection: Throughout the 2022 growing season (May 16th-September 30th) and 2023 growing season (May 1st- September 30th)

4. Site Description

Location:

The study site was in Basin 3 East of the Frank Lake Wetland Complex, a prairie pothole wetland located 6 km east of the town of High River, Alberta, Canada (Latitude: 50.567. N; Longitude: 113.708. W). Frank Lake was restored in 1989 aimed at enhancing bird habitat with municipal wastewater and agro-industrial wastewater and to date, the wetland continues to receive inputs from these effluent water sources.

Climate Conditions:

The climate of Frank Lake is typical of the semi-arid Canadian prairies, with cold winters and warm summers. The long-term climate data recorded at the Blackie weather station located 4 km from Frank Lake Basin 3 East (Blackie AGCM, Latitude: 50.5458 N, Longitude: 113.6403 W; www.acis.alberta.ca) is available for weather data recorded in 2022-23 in comparison to long-term average patterns (climate normal) for the study area.

Vegetation/Cover:

The wetland vegetation was dominated by the emergent aquatic plant, bulrush (Schoenoplectus acutus L.). Details of the vegetation distribution and abundance are described in the associated publication for this data set.

5. Information about funding sources that supported the collection of the data:

Funds to support this study were provided by the Natural Sciences and Engineering Council of Canada (NSERC) – Alliance and Discovery Grant Programs, and Alberta Environment and Parks.

 SHARING/ACCESS INFORMATION

1. Licenses/restrictions placed on the data: None
2. Links to publications that cite or use the data: TBD
3. Links to other publicly accessible locations of the data: None
4. Links/relationships to ancillary data sets: None
5. Was data derived from another source? No
6. Recommended citation for this dataset:

W. Oshini K. Fernando, Samuel G. Woodman, Stewart B. Rood, Lawrence B. Flanagan. Carbon sequestration capacity of a prairie pothole wetland under warm and dry conditions. Agricultural and Forest Meteorology 

DATA & FILE OVERVIEW

1. File List:

FL_Flux_05_2022.csv
FL_Flux_06_2022.csv
FL_Flux_07_2022.csv
FL_Flux_08_2022.csv
FL_Flux_09_2022.csv
FL_Flux_05_2023.csv
FL_Flux_06_2023.csv
FL_Flux_07_2023.csv
FL_Flux_08_2023.csv
FL_Flux_09_2023.csv
FL_Met_05_2022.csv
FL_Met_06_2022.csv
FL_Met_07_2022.csv
FL_Met_08_2022.csv
FL_Met_09_2022.csv
FL_Met_05_2023.csv
FL_Met_06_2023.csv
FL_Met_07_2023.csv
FL_Met_08_2023.csv
FL_Met_09_2023.csv
FL_CBudget_Daily_2022.csv
FL_CBudget_Daily_2023.csv

2. Relationship between files, if important: NA
3. Additional related data collected that was not included in the current data package: NA
4. Are there multiple versions of the dataset? No

DATA_SPECIFIC METHODOLOGICAL INFORMATION FOR FILES:

FL_Flux_05_2022.csv, FL_Flux_06_2022.csv, FL_Flux_07_2022.csv, FL_Flux_08_2022.csv, FL_Flux_09_2022.csv, FL_Flux_05_2023.csv, FL_Flux_06_2023.csv, FL_Flux_07_2023.csv, FL_Flux_08_2023.csv, FL_Flux_09_2023.csv

1. Description of methods used for collection/generation of data:

System Design

1. Site Description
Described above

2. Instrumentation
Eddy Covariance System Components:

Sonic Anemometer (HS-50, Gill) to measure wind speed and direction in three dimensions and air temperature fluctuations.
Carbon dioxide and water vapour analyzer (LI-7500 RS, Li-COR) to measure the concentration of CO₂ and H₂O.
Methane analyzer (LI-7700 RS, Li-COR) to measure the concentration of CH4
Analyzer Interface Unit (LI-7550-AIU, Li-COR) that functions as a datalogger and stores data on a USB storage drive.

Height and Positioning:

The flux tower was located on an island near the center of the Basin 3 East of Frank Lake where extensive ground coverage of S. acutus occurred, and there was flat, uniform fetch of c. 200 m in all directions surrounding the eddy covariance tower. The midpoint points for the sensor path on the sonic anemometer and open path gas analyzers were all at 4.5 m above ground.

Data Logger and Storage:

High frequency data (10 Hz) were stored as Li-Cor ghg files on a USB storage drive and subsequently processed to 30-minute average flux files using EddyPro software.

System maintenance

Routine maintenance (weekly/biweekly) was performed on the eddy covariance system to ensure the quality and accuracy of flux measurements over time. The major maintenance procedures are mentioned below.

Inspecting the sonic anemometer and infrared gas analyzer (IRGA) for any physical damage, debris, or obstructions (e.g., bird droppings, dirt, or dust) and checking all cables for loose connections.

Ensuring that the tower or tripod holding the sensors was stable.

Ensuring that the solar panels were clean, and batteries were charging adequately to power the system.

Cleaning the optical windows of the open-path Infrared Gas Analyzers (IRGA) with a lint-free cloth and water.

Calibration checks were routinely made at approximately 10-14 day intervals for the gas concentration zero and span settings using calibration gases traceable to international standards.

Checking the data logger and USB storage drive to ensure data was being recorded properly. Also, downloading data and inspected for any irregularities (e.g., data gaps, outliers).

Data Collection

Sampling Frequency:

Signals from the sonic anemometer and gas analyzers were sampled at a frequency of 10 Hz by the associated Analyzer Interface Unit.

Duration of Measurements:

Throughout the 2022 growing season (May 16th-September 30th) and 2023 growing season (May 1st- September 30th)

Calibration:

Gas analyzers were regularly checked for span and zero calibration using working standard calibration gas cylinders that had been calibrated relative to international standards using calibration tanks provided by the Greenhouse gas Lab at Environment Canada in Toronto, Ontario, Canada.

2. Methods for processing the data:
Processing of high-frequency eddy flux was performed with EddyPro software (v7.0.9).

3. Instrument- or software-specific information needed to interpret the data:
·         EddyPro (v7.0.9, LI-COR)

4. Standards and calibration information, if appropriate:
NA

5. Environmental/experimental conditions:
Described above

6. Describe any quality-assurance procedures performed on the data:
Described above

7. People involved with sample collection, processing, analysis and/or submission:
Lawrence B Flanagan, W. Oshini K. Fernando, Samuel G. Woodman, Stewart B. Rood.

8. Column Variable List:

9. Missing data codes:
Missing data are denoted by "-9999".

10. Specialized formats or other abbreviations used:
NA

DATA_SPECIFIC METHODOLOGICAL INFORMATION FOR FILES:

FL_Met_05_2022.csv, FL_Met_06_2022.csv, FL_Met_07_2022.csv, FL_Met_08_2022.csv, FL_Met_09_2022.csv, FL_Met_05_2023.csv, FL_Met_06_2023.csv, FL_Met_07_2023.csv, FL_Met_08_2023.csv, FL_Met_09_2023.csv

1. Description of methods used for collection/generation of data:

System design

Site Description

Described above

Instrumentation

Meteorological Instrumentation Tower Components:

Temperature and relative humidity probe (HMP45C, Campbell Scientific, Logan, UT, USA) to measure air temperature and relative humidity located within a naturally ventilated radiation shield, and Temperature Probe (107, Campbell Scientific) used to measure air temperature, both mounted at a height of 2 m above ground

Net radiometer (NR-LITE2, Campbell Scientific) for net radiation at a height of 3 m

Quantum sensor (LI190SB, LI-COR) to measure incoming photosynthetically active photon flux density (PPFD) at a height of 3 m

HydraProbes (HydraProbe, Stevens) to measure soil temperature, soil volumetric water content and soil electric conductivity were buried in soil at 15 cm depth at three different locations close to the meteorological tower

Soil heat flux plates (HFT3, Campbell Scientific) to measure soil heat flux at 5 cm depth at three locations adjacent to the HydraProbes

ClimaVUE™50 (Campbell Scientific) weather station mounted at a height of 3 m and used to measure total precipitation among other additional variables as noted below.

Height and Positioning:

Meteorological variables were measured simultaneously with the eddy fluxes using sensors mounted on an instrumentation tower located 30 m from the eddy covariance flux tower.

Data Logger and Storage:

All meteorological data were collected by a datalogger (CR1000X, Campbell Scientific, USA) located in a fiberglass enclosure.

System maintenance

Routine maintenance (weekly/biweekly) was performed on the meteorological instrumentation tower to ensure the quality and accuracy of measurements over time. The major maintenance procedures are mentioned below.

Inspecting the sensors for any physical damage, debris, or obstructions (e.g., bird droppings, dirt, or dust) and checking all cables for loose connections.

Ensuring that the tower or tripod holding the sensors was stable.

Ensuring that the solar panels were clean, and batteries were charging adequately to power the system.

Cleaning the radiation sensors attached to the tower with a lint-free cloth and water.

Checking the data logger and storage to ensure data was being recorded properly. Also, downloading data and inspecting it for any irregularities (e.g., data gaps, outliers).

Data Collection

Sampling Frequency:

All meteorological sensors (except for the rain gauge) were scanned at 60-s intervals and recorded as half-hourly means by the data logger. The rain gauge recorded total precipitation in 30-min intervals.

Duration of Measurements:

Throughout the 2022 growing season (May 16th-September 30th) and 2023 growing season (May 1st- September 30th)

Methods for processing the data:

The dataset provided consists of raw, unprocessed data collected directly from the meteorological instrumentation datalogger. No data processing, filtering, or post-collection analysis has been applied.

Instrument- or software-specific information needed to interpret the data:
NA

Standards and calibration information, if appropriate:
NA

Environmental/experimental conditions:
Described above

Describe any quality-assurance procedures performed on the data:
NA

People involved with sample collection, processing, analysis and/or submission:
Lawrence B Flanagan, W. Oshini K. Fernando, Samuel G. Woodman, Stewart B. Rood

Sensors used for measuring meteorological parameters:

9. Column Variable List:

Missing data codes:
Missing data are denoted by "-9999".

Specialized formats or other abbreviations used:
NA

DATA_SPECIFIC METHODOLOGICAL INFORMATION FOR FILES:

FL_CBudget_Daily_2022.csv, FL_CBudget_Daily_2023.csv

1. Description of methods used for collection/generation of data:

The flux data and meteorological data required for the derivation of GPP, TER, NEE and CH4NEE came from the Eddy Covariance System was described above.

2. Methods for processing the data:

GPP, TER and NEE

Mean diel patterns (bin-averages by time of day) of CO2 NEE (net ecosystem CO2 exchange), photosynthetic photon flux density (PPFD) and air temperature (T) were calculated for data from two-week periods during May to September 2022 and 2023, after screening out data when the CO2 quality signal from the LI-7500 analyzer dropped below 90%, removing extreme outliers (defined as observations greater than 3 standard deviations from the mean value) and also removing data from rain periods and periods with friction velocity below the established u* threshold of 0.12 m s−1. Mean diel trends were fitted to a non-linear equation to estimate key ecosystem parameters: maximum gross ecosystem photosynthesis (Amax), initial slope of the light-response curve (α), total ecosystem respiration at 10ºC (R10), and temperature sensitivity coefficient for respiration (Q10). Non-linear, least squares regression was used to estimate these parameters, with bounds set for each. The resulting equation was then applied to gap-fill the NEE data and partition it into gross ecosystem photosynthesis (GEP) and total ecosystem respiration (TER). Seasonal variations in Amax, α, R10, and Q10 were used to compute integrated CO₂ budgets over 15-day intervals, and daily-integrated values of gap-filled CO2 NEE, GEP, and TER were calculated using a sign convention where CO₂ release to the atmosphere is a positive value, and uptake of CO2 by the ecosystem is a negative value.

CH4 NEE

For the CH₄ NEE dataset in 2022, the data were screened out when the Received Signal Strength Indicator (RSSI) of the LI-7700 analyzer dropped below 20% and during rain periods and when friction velocity (u*) was below 0.12 m s⁻¹. In addition, extreme outliers were removed (defined as observations greater than 3 standard deviations from the mean value). Although we observed a distinct difference between daytime and nighttime CH₄ NEE throughout the 2022 growing season, there was no significant seasonal variation in CH₄ flux, so a mean diel pattern from all growing season data was used to gap-fill CH₄ NEE values for 2022. For the 2023 dataset, similar screening procedures were followed as described above, with distinct diel patterns observed from May to July. A fourth-order polynomial was fitted to combined diel data from May and June, and a separate polynomial to July diel data, to gap-fill missing values. In August and September, when no discernible diel trends were found, mean daily values were used for gap-filling missing values for a given day, and monthly averages were applied when all daily data were missing. Methane release to the atmosphere is a positive value and uptake of methane by the ecosystem is a negative value.

3. Instrument- or software-specific information needed to interpret the data:
NA

4. Standards and calibration information, if appropriate:
NA

5. Environmental/experimental conditions:
Described above

6. Describe any quality-assurance procedures performed on the data:
Described above

7. People involved with sample collection, processing, analysis and/or submission:
Lawrence B Flanagan, W. Oshini K. Fernando, Samuel G. Woodman, Stewart B. Rood.

8. Sensors used for measuring meteorological parameters:
NA

9. Missing data codes:
Missing data are denoted by "-9999".

10. Specialized formats or other abbreviations used:
NA

Column variable list: