Data Package Metadata View Summary

Time series of dissolved methane and carbon dioxide concentrations for Falling Creek Reservoir and Beaverdam Reservoir in southwestern Virginia, USA during 2015-2022

General Information

Data Package:

Local Identifier:

edi.997.4

Title:

Time series of dissolved methane and carbon dioxide concentrations for Falling Creek Reservoir and Beaverdam Reservoir in southwestern Virginia, USA during 2015-2022

Alternate Identifier:

DOI PLACE HOLDER

Abstract:

Surface samples and depth profiles of carbon dioxide and methane concentrations were sampled from 2015 to 2022 in two drinking water reservoirs in southwestern Virginia, USA: Beaverdam Reservoir (Vinton, Virginia) and Falling Creek Reservoir (Vinton, Virginia). Both reservoirs are owned and operated by the Western Virginia Water Authority as primary or secondary drinking water sources for Roanoke, Virginia. The dataset consists of depth profiles of dissolved greenhouse gas (carbon dioxide, methane) samples measured at the deepest site of each reservoir adjacent to the dam. Additional surface samples were collected at a gauged weir on Falling Creek Reservoir's primary inflow tributary, from a wetland adjacent to Falling Creek Reservoir, and from the reservoir outflow. At Beaverdam Reservoir, additional samples were collected at three outflow points below the dam and at the mid-reservoir outflow. Samples were collected approximately fortnightly from March-April, weekly from May-October, and monthly in November-February at Falling Creek Reservoir and Beaverdam Reservoir. In 2019, surface samples along the stream and reservoir continuum from both Falling Creek Reservoir and Beaverdam Reservoir were collected monthly during the summer stratified period.

Publication Date:

2023-01-13

For more information:
Visit:	DOI PLACE HOLDER

Time Period

Begin:

2015-03-31

End:

2022-05-23

People and Organizations
Contact:	Carey, Cayelan C. (Virginia Tech) [ email ]
Creator:	Carey, Cayelan C. (Virginia Tech)
Creator:	Lewis, Abigail S.L. (Virginia Tech)
Creator:	Niederlehner, B. R. (Virginia Tech)
Creator:	Breef-Pilz, Adrienne (Virginia Tech)
Creator:	Das, Arpita (Virginia Tech)
Creator:	Geisler, Beckett (Virginia Tech)
Creator:	Haynie, George (Virginia Tech)

Data Entities
Data Table Name:	GHG Dataset
Description:	GHG Dataset
Data Table Name:	Site Descriptions
Description:	Descriptions of sites in this dataset with lat/long coordinates
Other Name:	QA/QC Code
Description:	R script for GHG QA/QC

Detailed Metadata

Data Entities

Data Table


Data:	https://pasta-s.lternet.edu/package/data/eml/edi/997/4/38d72673295864956cccd6bbba99a1a3
Name:	GHG Dataset
Description:	GHG Dataset
Number of Records:	6047
Number of Columns:	10

Table Structure

Object Name:

Dissolved_GHG_2015_2022.csv

Size:

407094 bytes

Authentication:

fa7fab1a78c1c624e85606672cce88e2 Calculated By MD5

Text Format:

Number of Header Lines:

Record Delimiter:

Orientation:

column

Simple Delimited:

Field Delimiter:

Table Column Descriptions

Column Name:

Reservoir

Site

DateTime

Depth_m

Rep

CH4_umolL

CO2_umolL

Flag_DateTime

Flag_CH4_umolL

Flag_CO2_umolL

Definition:

Three-letter code corresponding to sampled reservoir; FCR = Falling Creek Reservoir; BVR = Beaverdam Reservoir

Sampling site (see site_descriptions.csv for more information)

Date and time of sampling. All data were collected in the eastern time zone of the U.S.A., with daylight savings time observed

Water depth where the sample was collected

Field replicates collected at the same site, date, and depth

Dissolved methane concentration

Dissolved carbon dioxide concentration

Flag value for DateTime; 0 = Time recorded; 1 = Time not recorded and set to 12:00

Flag value for methane concentration; 0 = the samples and replicates are good; 1 = Sample was either not collected or was not retained due to issues with the GC; 2 = Sample was below the method detection limit; 3 = Sample value was negative and changed to zero; 4 = The difference between the reps are above the limit of quantification and >30% and <50% different from each other. Both replicates were retained but flagged; 5 = The difference between the reps are above the limit of quantification and >50% different from each other. Both replicates were retained but flagged.

Flag value for carbon dioxide concentration; 0 = the samples and replicates are good; 1 = Sample was either not collected or was not retained due to issues with the GC; 2 = Sample was below the method detection limit; 3 = Sample value was negative and changed to zero; 4 = The difference between the reps are above the limit of quantification and >30% and <50% different from each other. Both replicates were retained but flagged; 5 = The difference between the reps are above the limit of quantification and >50% different from each other. Both replicates were retained but flagged.

Storage Type:

string

float

date

float

Measurement Type:

nominal

ratio

dateTime

ratio

Measurement Values Domain:

Definition

Three-letter code corresponding to sampled reservoir; FCR = Falling Creek Reservoir; BVR = Beaverdam Reservoir

Unit	dimensionless
Type	real
Min	1
Max	200

Format	YYYY-MM-DD hh:mm:ss
Precision

Unit	meter
Type	real
Min	0
Max	200

Unit	dimensionless
Type	natural
Min	1
Max	4

Unit	micromolePerLiter
Type	real
Min	0
Max	790.2280281

Unit	micromolePerLiter
Type	real
Min	0
Max	1258.93220898998

Unit	dimensionless
Type	whole
Min	0
Max	1

Unit	dimensionless
Type	whole
Min	0
Max	4

Unit	dimensionless
Type	whole
Min	0
Max	4

Missing Value Code:

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Accuracy Report:

Accuracy Assessment:

Coverage:

Methods:

Data Table


Data:	https://pasta-s.lternet.edu/package/data/eml/edi/997/4/245886d5a324d63c7877574ba377263a
Name:	Site Descriptions
Description:	Descriptions of sites in this dataset with lat/long coordinates
Number of Records:	22
Number of Columns:	5

Table Structure

Object Name:

site_descriptions.csv

Size:

2496 bytes

Authentication:

3a60f8df6e982969420c0c707d50d9a9 Calculated By MD5

Text Format:

Number of Header Lines:

Record Delimiter:

Orientation:

column

Simple Delimited:

Field Delimiter:

Table Column Descriptions

Column Name:

Reservoir

Site

Site_description

Latitude

Longitude

Definition:

Three-letter code corresponding to sampled reservoir

Sampling site within each reservoir

Description of sampling site

Site latitude

Site longitude

Storage Type:

string

float

string

float

Measurement Type:

nominal

ratio

nominal

ratio

Measurement Values Domain:

Definition

Three-letter code corresponding to sampled reservoir

Unit	dimensionless
Type	real
Min	1
Max	200

Definition

Description of sampling site

Unit	degree
Type	real
Min	37.3021056538632
Max	37.322851

Unit	degree
Type	real
Min	-79.8383
Max	79.8360878

Missing Value Code:

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Code	NA
Expl	value is missing

Accuracy Report:

Accuracy Assessment:

Coverage:

Methods:

Non-Categorized Data Resource

Name:

QA/QC Code

Entity Type:

unknown

Description:

R script for GHG QA/QC

Physical Structure Description:

Object Name:

QAQC_GHG_2022.R

Size:

34628 bytes

Authentication:

e6d7a9ea8b4811dc3309aa89d47a348c Calculated By MD5

Externally Defined Format:

Format Name:

text/plain

Data:

https://pasta-s.lternet.edu/package/data/eml/edi/997/4/445413282a3e212bf270053c7ea88786

Data Package Usage Rights

This information is released under the Creative Commons license - Attribution - CC BY (https://creativecommons.org/licenses/by/4.0/). The consumer of these data ("Data User" herein) is required 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. Thank you.

Keywords

By Thesaurus:
carey lab controlled vocabulary	greenhouse gas, Virginia Tech, Stream Team, Western Virginia Water Authority, Falling Creek Reservoir, Beaverdam Reservoir, Carey Lab
cuahsi controlled vocabulary	reservoir, lake
lter controlled vocabulary	depth, methane, carbon dioxide, lakes

Methods and Protocols

These methods, instrumentation and/or protocols apply to all data in this dataset:

Methods and protocols used in the collection of this data package

Description:

SAMPLE COLLECTION AND EQUIPMENT

Samples for greenhouse gas (methane, carbon dioxide) analysis were collected from Falling Creek Reservoir and Beaverdam Reservoir between 2015 - 2022. Most sampling occurred between the hours of 9:00 and 15:00; however, some sampling occurred outside of these hours, including some overnight sampling. For more information about nighttime sampling, see Doubek et. al. 2018. Exact sampling times were included in the DateTime column starting in 2018. After 2018, exact times, when recorded during sample collection, are indicated in the DateTime column with a Flag_DateTime value of 0. If exact times were not recorded during sample collection, time was standardized to 12:00 and Flag_DateTime was set to 1. Prior to 2018, sample timestamps for samples collected between approximately 9:00 and 15:00 were standardized to noon and Flag_DateTime was set to 1.

Samples were collected from several routine depths at the deepest holes of both reservoirs (Site = 50 in both reservoirs) including: 0.1, 1.6, 3.8, 5.0, 6.2, 8.0, and 9.0 m in Falling Creek Reservoir and 0.1, 3.0, 6.0, 9.0, and 11.0 m for Beaverdam Reservoir. These sampling depths were chosen to approximately match outtake valves in Falling Creek Reservoir and Beaverdam Reservoir. Samples were collected with a 4-L Van Dorn sampler (Wildlife Supply, Yulee, FL, USA) and transferred to into two replicate 20 mL glass vials without exposure to air and crimp sealed. These routine depth samples were collected approximately fortnightly from March-April, weekly from May-October, and monthly in November-February.

Surface samples from Falling Creek Reservoir were also collected at a gauged weir on the primary inflow (Tunnel Branch) to Falling Creek Reservoir (Site = 100), at the wetland stream (Falling Creek) adjacent to the reservoir (Site = 200), and at the reservoir outflow at the dam (Site = 1.1). In Beaverdam Reservoir, additional surface samples were collected from the several sites at the outflow below the dam (Site = 1.1, 1.2, 1.3, 1.4) and at the Mid-Reservoir Outflow Pipe (Site = 40). These samples were collected approximately fortnightly from May-October and monthly in November-April.

In summer 2019, additional surface samples were collected approximately monthly along the stream and reservoir continuum for both Falling Creek Reservoir and Beaverdam Reservoir as part of the Reservoir Continuum project (Falling Creek Reservoir: Creek Sites = 99, 100, 101, 102, 200; Reservoir Sites = 20, 30, 45, 50; Reservoir Outflow = 1 and Beaverdam Reservoir: Creek Sites = 100, 200; Reservoir Sites = 20, 30, 45, 50; Mid-Reservoir Outflow Pipe = 40). Surface samples were collected via grab samples for all stream and up-stream reservoir locations. All samples were stored on ice and analyzed within 24 hours of collection following McClure et al. (2018).

All sites are described with geographic coordinates in the site_descriptions.csv data file.

SAMPLE ANALYSIS AND EQUIPMENT

Dissolved methane and carbon dioxide concentrations were measured in each water sample on a Gas Chromatograph (GC) with a Flame Ionization Detector (FID) and Thermal Conductivity Detector (TCD) following McClure et al. (2018). Briefly, immediately prior to analysis, a 2-mL headspace was created with Helium (He) by displacing 2-mL of sample water. The headspace was equilibrated by shaking each 20-mL vial at 300 rpm for 15 minutes. The 2-mL headspace was then injected into the GC. The oven temperature was set to 35 degrees C with a carrier gas (He) flow rate of 15 mL/min. CH4 had a retention time of 1.3 min on the FID and CO2 had a retention time of 2.8 min on the TCD. Dissolved concentrations of CH4 and CO2 in water were calculated using the observed head-space concentrations and Henry's Law (McClure et al. 2018). From 2015-2018, samples were analyzed on a GC SRI, Model 8010. From 2019-onwards, samples were analyzed on a Shimadzu Nexis GC-2030.

DATA FLAGS

Replicate samples (Rep 1 and 2) were often collected for each Date, Site, and Depth. If a second rep was not collected, the data was flagged as '1' (sample was not collected). If the analyzed sample had a value below the minimum detection limit (MDL) the sample was flagged as '2' (sample below MDL). A running MDL was calculated for each GC separately (2015-2018, GC SRI, Model 8010; 2019-onwards, Shimadzu Nexis GC-2030) from routinely measured air concentrations throughout the year and calculated using a consistent temperature (2015-2018 20 deg C; 2019-2022 40 deg C) and pressure (30 psi). MDL for each year is presented; 2015 CH4 = 0.001 umol/L, CO2 = 2.13 umol/L; 2016 CH4 = 0.006 umol/L, CO2 = 4.45 umol/L; 2017 CH4 = 0.005 umol/L, CO2 = 12.70 umol/L; 2018 CH4 = 0.005 umol/L, CO2 = 21.84 umol/L; 2019 CH4 = 0.011 umol/L, CO2 = 5.08 umol/L; 2020 CH4 = 0.013 umol/L, CO2 = 6.17 umol/L; 2021 CH4 = 0.021 umol/L, CO2 = 5.74 umol/L; 2022 CH4 = 0.0107 umol/L, CO2 = 3.848 umol/L. If the sample had a negative value, the sample value was set to 0 and flagged as '3'. Replicates of each sample were assessed after sample analysis using calculated percent difference between replicate samples as well as the limit of quantification (LOQ = 3*MDL). If the difference between replicate samples was < LOQ, then the samples were not flagged ('0', samples are good). If the difference between samples was >LOQ and the percent difference between replicates samples was <30%, then the samples were not flagged ('0', samples are good). If the difference between samples was >LOQ and the percent difference between replicates was >30% but <50%, then the samples were flagged as '4' (difference between reps is above LOQ and above 30% difference and below 50% difference). If the difference between samples was >LOQ and the percent difference between replicates was >50%, then the samples were flagged '5' (difference between reps is above the LOQ and above 50% different). For all flags, replicates were retained in the dataset.

DATA PACKAGE UPDATES

We note several updates to the current data package following multiple revisions of earlier versions of this dataset. First, we now set any negative greenhouse gas values (methane or carbon dioxide) to zero, following best practices. Any samples that had a negative value have been flagged "3". In addition, we standardized the calculation of MDLs for both methane and carbon dioxide to include a running MDL for all air samples analyzed during each respective year. Importantly, all MDLs are now calculated using a standard temperature (2015-2018 = 20 deg C; 2019-2022 = 40 deg C) and pressure (30 PSI).

WHOLE-ECOSYSTEM EXPERIMENTS

Multiple whole-ecosystem experiments have been conducted at Falling Creek Reservoir, including intermittent operation of hypolimnetic oxygenation (HOx) and pulsed epilimnetic mixing (EM) engineering systems. We encourage you to contact the lead author of the data package for more information.

REFERENCES

Doubek J.P., Campbell K.L., Doubek K.M., Hamre K.D., Lofton M.E., McClure R.P., Ward N.K., Carey C.C. (2018). The effects of hypolimnetic anoxia on the diel vertical migration of freshwater crustacean zooplankton. Ecosphere, 9(7):02332. https://doi.org/10.1002/ecs2.2332

Hounshell A.G., McClure R.P., Lofton M.E., Carey C.C. (2020). Whole-ecosystem oxygenation experiments reveal substantially greater hypolimnetic methane concentrations in reservoirs during anoxia. Limnology and Oceaography - Letters, 6: 33-42. https://doi.org/10.1002/lol2.10173

McClure R.P., Hamre K.D., Niederlehner B.R., Munger Z.W., Chen S., Lofton M.E., Schreiber M.E., Carey C.C. (2018). Metalimnetic oxygen minima alter the vertical profiles of carbon dioxide and methane in a managed freshwater reservoir. Science of the Total Environment, 636. pp. 610-620. https://doi.org/10.1016/j.scitotenv.2018.04.255

People and Organizations

Publishers:

Organization:

Environmental Data Initiative

Email Address:

info@edirepository.org

Web Address:

https://edirepository.org

Id:

https://ror.org/0330j0z60

Creators:

Individual:

Cayelan C. Carey

Organization:

Virginia Tech

Email Address:

Cayelan@vt.edu

Id:

https://orcid.org/0000-0001-8835-4476

Individual:

Abigail S.L. Lewis

Organization:

Virginia Tech

Email Address:

aslewis@vt.edu

Id:

https://orcid.org/0000-0001-9933-4542

Individual:

B. R. Niederlehner

Organization:

Virginia Tech

Email Address:

bniederl@vt.edu

Id:

https://orcid.org/0000-0002-6933-336X

Individual:

Adrienne Breef-Pilz

Organization:

Virginia Tech

Email Address:

abreefpilz@vt.edu

Id:

https://orcid.org/0000-0002-6759-0063

Individual:

Arpita Das

Organization:

Virginia Tech

Email Address:

arpitadas@vt.edu

Id:

https://orcid.org/0000-0002-9679-0873

Individual:	Beckett Geisler
Organization:	Virginia Tech

Individual:	George Haynie
Organization:	Virginia Tech

Contacts:

Individual:

Cayelan C. Carey

Organization:

Virginia Tech

Email Address:

Cayelan@vt.edu

Id:

https://orcid.org/0000-0001-8835-4476

Temporal, Geographic and Taxonomic Coverage

Temporal, Geographic and/or Taxonomic information that applies to all data in this dataset:

Time Period

Begin:

2015-03-31

End:

2022-05-23

Geographic Region:

Description:

Beaverdam Reservoir is located in Vinton, Virginia, USA

Bounding Coordinates:

Northern:	37.322865	Southern:	37.311961
Western:	-79.824834	Eastern:	-79.813848

Geographic Region:

Description:

Falling Creek Reservoir is located in Vinton, Virginia, USA

Bounding Coordinates:

Northern:	37.309589	Southern:	37.30266
Western:	-79.839249	Eastern:	-79.836009

Project

Parent Project Information:

Title:

No project title to report

Personnel:

Individual:

Cayelan C. Carey

Organization:

Virginia Tech

Email Address:

Cayelan@vt.edu

Id:

https://orcid.org/0000-0001-8835-4476

Role:

Principal Investigator

Funding:

Western Virginia Water Authority

Related Project:

Title:

Collaborative Research: Consequences of changing oxygen availability for carbon cycling in freshwater ecosystems

Personnel:

Individual:

Cayelan C. Carey

Organization:

Virginia Tech

Email Address:

Cayelan@vt.edu

Id:

https://orcid.org/0000-0001-8835-4476

Role:

Principal Investigator

Funding:

National Science Foundation 1753639

Related Project:

Title:

Collaborative Research: CIBR: Cyberinfrastructure Enabling End-to-End Workflows for Aquatic Ecosystem Forecasting

Personnel:

Individual:

Cayelan C. Carey

Organization:

Virginia Tech

Email Address:

Cayelan@vt.edu

Id:

https://orcid.org/0000-0001-8835-4476

Role:

Principal Investigator

Funding:

National Science Foundation 1933016

Related Project:

Title:

Collaborative Research: CIBR: Cyberinfrastructure Enabling End-to-End Workflows for Aquatic Ecosystem Forecasting

Personnel:

Individual:

Renato J. Figueiredo

Organization:

University of Florida

Email Address:

reanto@acis.ufl.edu

Id:

https://orcid.org/0000-0001-9841-6060

Role:

Principal Investigator

Funding:

National Science Foundation 1933102

Maintenance

Maintenance:

Description:	ongoing
Frequency:

Additional Info

Additional Information:

Contributions to the 2022 revision:

CCC developed and led the reservoir monitoring program. ASL led data collation, QAQC, and publishing for the 2022 revision. BRN performed sample analyses. ABP led the 2022 field crew and contributed substantially to fieldwork. AD collated data and assisted with field monitoring preparations; BG and GH contributed to fieldwork and field monitoring preparations in 2022.

Acknowledgments and historical contributions:

This data package has been iteratively updated over time and builds on the many historical contributions of co-authors listed in previous revisions. We thank the Western Virginia Water Authority for providing access to these sites, the Reservoir Group for contributing to fieldwork, and Alexandria Hounshell for contributing to QAQC and data collation in 2022.

Other Metadata

Additional Metadata

additionalMetadata
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        |     |___element 'unitList'
        |     |     |___text '\n        '
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        |     |     |     |  \___attribute 'id' = 'micromolePerLiter'
        |     |     |     |  \___attribute 'multiplierToSI' = '1.00E-06'
        |     |     |     |  \___attribute 'name' = 'micromolePerLiter'
        |     |     |     |  \___attribute 'parentSI' = 'molarity'
        |     |     |     |  \___attribute 'unitType' = 'amountOfSubstanceConcentration'
        |     |     |     |___text '\n          '
        |     |     |     |___element 'description'
        |     |     |     |     |___text 'micromole per liter'
        |     |     |     |___text '\n        '
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Additional Metadata

additionalMetadata
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Copyright 2024 Environmental Data Initiative. This material is based upon work supported by the National Science Foundation under grants #2223103 and #2223104. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. Please contact us with questions, comments, or for technical assistance regarding this web site or the Environmental Data Initiative. Please read our privacy policy to know what information we collect about you and to understand your privacy rights.

EDI is a collaboration between the University of New Mexico and the University of Wisconsin – Madison, Center for Limnology:

Data Package Metadata View Summary

Time series of dissolved methane and carbon dioxide concentrations for Falling Creek Reservoir and Beaverdam Reservoir in southwestern Virginia, USA during 2015-2022

Data Entities

Data Table

Data Table

Non-Categorized Data Resource

Data Package Usage Rights

Keywords

Methods and Protocols

These methods, instrumentation and/or protocols apply to all data in this dataset:

People and Organizations

Temporal, Geographic and Taxonomic Coverage

Project

Parent Project Information:

Maintenance

Additional Info

Additional Metadata

Additional Metadata

Recently Added

Recently Updated

Data Package Metadata View Summary

Time series of dissolved methane and carbon dioxide concentrations for Falling Creek Reservoir and Beaverdam Reservoir in southwestern Virginia, USA during 2015-2022

+/- Data Entities

Data Table

Data Table

Non-Categorized Data Resource

+/- Data Package Usage Rights

+/- Keywords

+/- Methods and Protocols

These methods, instrumentation and/or protocols apply to all data in this dataset:

+/- People and Organizations

+/- Temporal, Geographic and Taxonomic Coverage

+/- Project

Parent Project Information:

+/- Maintenance

+/- Additional Info

+/- Additional Metadata

+/- Additional Metadata

Data Entities

Data Package Usage Rights

Keywords

Methods and Protocols

People and Organizations

Temporal, Geographic and Taxonomic Coverage

Project

Maintenance

Additional Info

Additional Metadata

Additional Metadata