Data Package Metadata   View Summary

Time series of high-frequency profiles of depth, temperature, dissolved oxygen, conductivity, specific conductivity, chlorophyll a, turbidity, pH, oxidation-reduction potential, photosynthetically active radiation, colored dissolved organic matter, phycocyanin, phycoerythrin, and descent rate for Beaverdam Reservoir, Carvins Cove Reservoir, Falling Creek Reservoir, Gatewood Reservoir, and Spring Hollow Reservoir in southwestern Virginia, USA 2013-2023

General Information
Data Package:
Local Identifier:edi.1113.5
Title:Time series of high-frequency profiles of depth, temperature, dissolved oxygen, conductivity, specific conductivity, chlorophyll a, turbidity, pH, oxidation-reduction potential, photosynthetically active radiation, colored dissolved organic matter, phycocyanin, phycoerythrin, and descent rate for Beaverdam Reservoir, Carvins Cove Reservoir, Falling Creek Reservoir, Gatewood Reservoir, and Spring Hollow Reservoir in southwestern Virginia, USA 2013-2023
Alternate Identifier:DOI PLACE HOLDER
Abstract:

Depth profiles of water biogeochemical properties were collected with SeaBird Electronics (SBE) Conductivity, Temperature, and Depth (CTD) profilers from 2013-2023. Data availability differs across years due to additional sensors that have been added or replaced over time. From 2013-2016, profiles were taken with a CTD equipped with an SBE 43 Dissolved Oxygen sensor and an ECO FLNTU sensor for turbidity and chlorophyll. From 2017-2023, profiles were taken with a CTD equipped with an SBE 43 Dissolved Oxygen sensor, an ECO FLNTU sensor for turbidity and chlorophyll, a PAR-LOG ICSW sensor for photosynthetically active radiation, and a SBE 27 pH and ORP (oxidation-reduction potential) sensor. In 2022 and 2023, profiles were also taken with an additional CTD equipped with an SBE 43 Dissolved Oxygen sensor, an ECO Triplet Scattering Fluorescence sensor for CDOM, phycocyanin, and phycoerythrin, an ECO FLNTU sensor for turbidity and chlorophyll, and PAR-LOG ICSW for photosynthetically active radiation. CTD profiles were collected in five drinking water reservoirs in southwestern Virginia, USA. All variables were measured every 0.25 seconds, resulting in depth profiles at approximately ten centimeter resolution. The five study reservoirs are: Beaverdam Reservoir (Vinton, Virginia), Carvins Cove Reservoir (Roanoke, Virginia), Falling Creek Reservoir (Vinton, Virginia), Gatewood Reservoir (Pulaski, Virginia), and Spring Hollow Reservoir (Salem, Virginia). Beaverdam, Carvins Cove, Falling Creek, and Spring Hollow Reservoirs are owned and operated by the Western Virginia Water Authority as primary or secondary drinking water sources for Roanoke, Virginia, and Gatewood Reservoir is a drinking water source for the town of Pulaski, Virginia. The dataset consists of CTD depth profiles measured at the deepest site of each reservoir adjacent to the dam as well as other upstream reservoir sites. The profiles were collected approximately fortnightly in the spring months, weekly in the summer and early autumn, and monthly in the late autumn and winter. Beaverdam Reservoir, Carvins Cove Reservoir, and Falling Creek Reservoir were sampled every year in the dataset (2013-2023); Spring Hollow Reservoir was only sampled 2013-2017 and 2019; and Gatewood Reservoir was only sampled in 2016.

Publication Date:2024-04-19
For more information:
Visit: DOI PLACE HOLDER

Time Period
Begin:
2013-03-07
End:
2023-12-04

People and Organizations
Contact:Carey, Cayelan C. (Virginia Tech) [  email ]
Creator:Carey, Cayelan C. (Virginia Tech)
Creator:Lewis, Abigail S. L. (Virginia Tech)
Creator:Breef-Pilz, Adrienne (Virginia Tech)

Data Entities
Data Table Name:
CTD dataset 2013-2023
Description:
Reservoir CTD dataset
Data Table Name:
Descriptions of sample sites
Description:
Sample site descriptions
Other Name:
QAQC script
Description:
High-level QAQC script used to process data from 2018-2023 - references scripts in helper_scripts.zip
Other Name:
Helper scripts
Description:
Scripts used to compile casts and apply QAQC, as referenced by CTD_QAQC_2018_2023.R
Detailed Metadata

Data Entities


Data Table

Data:https://pasta-s.lternet.edu/package/data/eml/edi/1113/5/0432a298a90b2b662f26c46071f66b8a
Name:CTD dataset 2013-2023
Description:Reservoir CTD dataset
Number of Records:1282987
Number of Columns:34

Table Structure
Object Name:CTD_2013_2023.csv
Size:194379656 bytes
Authentication:697b47c44f015ef139e2214c4e300220 Calculated By MD5
Text Format:
Number of Header Lines:1
Record Delimiter:\n
Orientation:column
Simple Delimited:
Field Delimiter:,

Table Column Descriptions
 
Column Name:Reservoir  
Site  
DateTime  
Depth_m  
SN  
Temp_C  
DO_mgL  
DOsat_percent  
Cond_uScm  
SpCond_uScm  
Chla_ugL  
Turbidity_NTU  
pH  
ORP_mV  
PAR_umolm2s  
CDOM_ugL  
Phycoerythrin_ugL  
Phycocyanin_ugL  
DescRate_ms  
Flag_DateTime  
Flag_Temp_C  
Flag_DO_mgL  
Flag_DOsat_percent  
Flag_Cond_uScm  
Flag_SpCond_uScm  
Flag_Chla_ugL  
Flag_Turbidity_NTU  
Flag_pH  
Flag_ORP_mV  
Flag_PAR_umolm2s  
Flag_CDOM_ugL  
Flag_Phycoerythrin_ugL  
Flag_Phycocyanin_ugL  
Flag_DescRate_ms  
Definition:Three-letter code corresponding to sampled reservoirSampling site within each reservoir (see site_descriptions.csv file included in this data package)Date and time of sampling. All data were collected in the eastern time zone of the U.S.A., with daylight savings time observedWater depth where the sensor reading was measured; negative values indicate height above the water’s surfaceCTD serial number (see Methods)Water temperatureDissolved oxygen (DO) concentrationDissolved oxygen (DO) percent saturationConductivitySpecific conductance; conductivity normalized to 25 degrees celsiusChlorophyll aTurbidityWater pHReduction potentialPhotosynthetically active radiationColored dissolved organic matterPhycoerythrinPhycocyaninDescent rateData flag for date timeData flag for temperatureData flag for dissolved oxygen (DO) concentrationData flag for dissolved oxygen (DO) saturationData flag for conductivityData flag for specific conductivityData flag for chlorophyll aData flag for turbidityData flag for pHData flag for ORPData flag for photosynthetically active radiation (PAR)Data flag for CDOMData flag for PhycoerythrinData flag for PhycocyaninData flag for descent rate
Storage Type:string  
float  
date  
float  
string  
float  
float  
float  
float  
float  
float  
float  
float  
float  
float  
float  
float  
float  
float  
string  
string  
string  
string  
string  
string  
string  
string  
string  
string  
string  
string  
string  
string  
string  
Measurement Type:nominalratiodateTimerationominalratioratioratioratioratioratioratioratioratioratioratioratioratiorationominalnominalnominalnominalnominalnominalnominalnominalnominalnominalnominalnominalnominalnominalnominal
Measurement Values Domain:
Allowed Values and Definitions
Enumerated Domain 
Code Definition
CodeBVR
DefinitionBeaverdam Reservoir
Source
Code Definition
CodeCCR
DefinitionCarvins Cove Reservoir
Source
Code Definition
CodeFCR
DefinitionFalling Creek Reservoir
Source
Code Definition
CodeGWR
DefinitionGatewood Reservoir
Source
Code Definition
CodeSHR
DefinitionSpring Hollow Reservoir
Source
Unitdimensionless
Typereal
Min
Max50.9 
FormatYYYY-MM-DD hh:mm:ss
Precision
Unitmeter
Typereal
Min-0.222 
Max63.797 
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code4397
DefinitionCTD serial number 4397 (used from 2013 - 2016)
Source
Code Definition
Code7809
DefinitionCTD serial number 4397 (used from 2017 - present)
Source
Code Definition
Code8188
DefinitionCTD serial number 4397 (used from 2022 - present)
Source
Unitcelsius
Typereal
Min3.1253 
Max31.0735 
UnitmilligramsPerLiter
Typereal
Min
Max19.7582 
Unitpercent
Typereal
Min
Max211.892 
UnitmicroSiemenPerCentimeter
Typereal
Min0.071384 
Max466.855174 
UnitmicroSiemenPerCentimeter
Typereal
Min0.064 
Max720.16 
UnitmicrogramsPerLiter
Typereal
Min
Max258.1299 
Unitdimensionless
Typereal
Min
Max962.7232 
Unitdimensionless
Typereal
Min0.012 
Max16.439 
Unitmillivolt
Typereal
Min-1240.7455 
Max1159.2414 
UnitmicromolePerMeterSquaredPerSecond
Typereal
Min
Max4303 
UnitmicrogramsPerLiter
Typereal
Min
Max31.14 
UnitmicrogramsPerLiter
Typereal
Min
Max2.8968 
UnitmicrogramsPerLiter
Typereal
Min
Max43.8651 
UnitmetersPerSecond
Typereal
Min-4.859 
Max4.787 
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code7
DefinitionDatetime missing time (date is meaningful but not time)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to 0
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to 0
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to 0
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to NA
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to NA
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to 0
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to 0
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to 0
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Code Definition
Code8
DefinitionMeasurement outside of expected range but retained in dataset
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to NA
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to 0
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to 0
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code4
DefinitionNegative value set to 0
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Code Definition
Code6
DefinitionAbove water measurement removed (set to NA)
Source
Allowed Values and Definitions
Enumerated Domain 
Code Definition
Code0
DefinitionNot suspect
Source
Code Definition
Code1
DefinitionSample not taken
Source
Code Definition
Code2
DefinitionInstrument malfunction
Source
Code Definition
Code3
DefinitionSample below detection
Source
Code Definition
Code5
DefinitionNo sensor on CTD
Source
Missing Value Code:      
CodeNA
ExplNo data
 
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
CodeNA
ExplNo data
                             
Accuracy Report:                                                                    
Accuracy Assessment:                                                                    
Coverage:                                                                    
Methods:                                                                    

Data Table

Data:https://pasta-s.lternet.edu/package/data/eml/edi/1113/5/61d9898e36d75efb6c6fcdf052e6e284
Name:Descriptions of sample sites
Description:Sample site descriptions
Number of Records:32
Number of Columns:5

Table Structure
Object Name:site_descriptions.csv
Size:4080 bytes
Authentication:1191ec64eb3f390e31ba173c1f43fa83 Calculated By MD5
Text Format:
Number of Header Lines:1
Record Delimiter:\n
Orientation:column
Simple Delimited:
Field Delimiter:,

Table Column Descriptions
 
Column Name:Reservoir  
Site  
Site_description  
Latitude  
Longitude  
Definition:Three-letter code corresponding to sampled reservoirSampling site within each reservoirDescription of sampling siteSite latitudeSite longitude
Storage Type:string  
float  
string  
float  
float  
Measurement Type:nominalrationominalratioratio
Measurement Values Domain:
Allowed Values and Definitions
Enumerated Domain 
Code Definition
CodeBVR
DefinitionBeaverdam Reservoir
Source
Code Definition
CodeCCR
DefinitionCarvins Cove Reservoir
Source
Code Definition
CodeFCR
DefinitionFalling Creek Reservoir
Source
Unitdimensionless
Typereal
Min
Max50.9 
DefinitionDescription of sampling site
Unitdegree
Typereal
Min37.0443528070071 
Max37.4071 
Unitdegree
Typereal
Min-80.8632991493157 
Max-79.8159 
Missing Value Code:
CodeNA
Explvalue is missing
CodeNA
Explvalue is missing
 
CodeNA
Explvalue is missing
CodeNA
Explvalue is missing
Accuracy Report:          
Accuracy Assessment:          
Coverage:          
Methods:          

Non-Categorized Data Resource

Name:QAQC script
Entity Type:unknown
Description:High-level QAQC script used to process data from 2018-2023 - references scripts in helper_scripts.zip
Physical Structure Description:
Object Name:CTD_QAQC_2018_2023.R
Size:2795 bytes
Authentication:3946f12cd9f39831589fdbda2d6c9064 Calculated By MD5
Externally Defined Format:
Format Name:text/plain
Data:https://pasta-s.lternet.edu/package/data/eml/edi/1113/5/a65dba6f6a1fd20378368bdf11b40b6c

Non-Categorized Data Resource

Name:Helper scripts
Entity Type:unknown
Description:Scripts used to compile casts and apply QAQC, as referenced by CTD_QAQC_2018_2023.R
Physical Structure Description:
Object Name:helper_scripts.zip
Size:13059 bytes
Authentication:3deb90f77b78e7f2141ec8d2f99429ac Calculated By MD5
Externally Defined Format:
Format Name:application/zip
Data:https://pasta-s.lternet.edu/package/data/eml/edi/1113/5/aac087d856710a8dc224d49914dd9ae4

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 labCarey Lab, Virginia Tech, Oxidation-reduction potential, phycocyanin, phycoerythrin, Descent rate, Western Virginia Water Authority, Falling Creek Reservoir, Beaverdam Reservoir, Carvins Cove Reservoir, Spring Hollow Reservoir, Gatewood Reservoir, FCR, CCR, BVR, GWR, SHR, Virginia Reservoirs LTREB, LTREB, CTD, Virginia Reservoirs
cuahsiLake, Reservoir, High-frequency Sensors, Colored dissolved organic matter
lterwater temperature, Dissolved Oxygen, Conductivity, Specific conductance, Chlorophyll a, Turbidity, pH, Photosynthetic active radiation

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:

Depth profiles of multiple water quality variables were collected from 2013 through 2023 using two Conductivity, Temperature, and Depth (CTD) profilers from SeaBird Electronics (SBE, Bellevue Washington, USA).

Measurements were taken at multiple sites in five reservoirs. Beaverdam Reservoir, Carvins Cove Reservoir, and Falling Creek Reservoir were sampled every year in the dataset (2013-2023); Spring Hollow Reservoir was only sampled 2013-2017 and 2019; and Gatewood Reservoir was only sampled in 2016. Within their sampling duration, profiles were collected, at minimum, monthly between May to October (usually weekly or subweekly at Beaverdam Reservoir and Falling Creek Reservoir), and bimonthly between November to April. Most CTD casts were collected from 9:00 to 15:00, however, some occasional CTD casts were collected at night. Above-surface (i.e., air) temperature and PAR are included in the dataset for 2018–2023, and are denoted with a negative depth measurement that indicates the distance above the surface of the reservoir.

The CTDs were calibrated by the manufacturer according to the standards and practices of SBE and the companies that manufactured the secondary sensors coupled to the instrument. Calibration was performed yearly (usually in December-February) for our first CTD (serial numbers 4397 and 7809), except for the 2021 and 2022 field seasons, when calibration was delayed until August 2022 due to the ongoing COVID-19 pandemic. A second CTD (serial number 8188) was added in May 2022 and was returned for re-calibration of its turbidity and chl-a sensors in August - October 2022.

Flags indicate known or suspected issues with measured variables. We note that the Depth_m likely also includes marginal error over the course of the dataset, but this error is unquantified and unflagged. Due to the challenges of measuring pH, ORP, and turbidity in situ, we recommend caution in interpreting these data.

All casts from 2018-2022 were re-processed in the revision published in February 2024 to standardize data processing across years (see QAQC_2018_2023.R and referenced data processing scripts).

This data package includes the CTD data file (CTD_2013_2023.csv), QAQC R script (QAQC_2018_2023.R), maintenance log (CTD_Maintenance_Log.txt), visual inspection R script (CTD_visualization.R), sampling sites (site_descriptions.csv), and additional data processing scripts (update_seasonal_csvs.R, ctd_functions_automated.R, flag_seasonal_csvs.R, identify_new_files.R, process_CTD_file.R). The QAQC script processes and compiles raw .cnv files, removes outliers, and applies the maintenance log to clean the data files included in the package, sourcing functions provided in additional data processing scripts. The visual inspection script provides code for plotting the data files.

INSTRUMENTS, MANUAL, AND SERIAL NUMBERS USED BETWEEN 2013 - 2023

From 2013-2016, profiles were taken with our first CTD (serial number 4397) equipped with an SBE 43 Dissolved Oxygen sensor and an ECO FLNTU sensor for turbidity and chlorophyll. In spring 2017, this CTD had a major upgrade and received a new data recorder, pH/ORP sensor, and PAR sensor; all other sensors and pumps remained the same. As the CTD received a new motherboard with the data recorder upgrade, its serial number updated from 4397 to 7809. Thus, from 2017-2023, the serial number 7809 CTD was equipped with an SBE 43 Dissolved Oxygen sensor, an ECOFLNTU sensor for turbidity and chlorophyll, a PAR-LOG ICSW sensor for photosynthetically active radiation, and a SBE 27 pH and oxidation-reduction potential (ORP) sensor.

In May 2022, we added an additional, second CTD (serial number 8188) equipped with an SBE 43 Dissolved Oxygen sensor, an ECO Triplet Scattering Fluorescence Sensor, an ECO FLNTU sensor, and a PAR-LOG ICSW sensor.

During 2022-2023, we took simultaneous profiles with the two CTDs (serial numbers 7809 and 8188) on 42 occasions across three different reservoirs: Falling Creek Reservoir (24 casts), Beaverdam Reservoir (16 casts), and Carvins Cove Reservoir (2 casts). Casts were either collected at the same time ~1 m apart or in succession in the same location. We rounded depth observations to the nearest centimeter, then matched observations from the same day, reservoir, and depth. Using the mcr package in R (Potapov et al. 2023), we used the Passing-Babcock regression (Passing and Bablok 1983) and then used the Pearson correlation to test correspondence between the sensors on the two instruments. We used bootstrapping to quantify the slope and intercept estimates with confidence intervals from the Passing-Bablock regressions (Manuilova and Schuetzenmeister 2014). Good correspondence between CTDs would yield a slope near 1 and an intercept near 0, and a 95% confidence interval that does not include these best-case values indicates a statistically significant difference. If a slope was significantly different from 1, we evaluated both the magnitude of the difference and plots of residuals vs. concentrations. If there was no clear pattern over increasing values, the correspondence was judged acceptable.

Below are the results of the comparison between the two CTDs, with the statistics from the Passing-Babcock regression and the Pearson correlation coefficient for each variable measured by the instruments:

- Temp_C (2022 - 2023; n = 791): The Passing-Babcock regression slope was 1.00 (0.997-1.001), the intercept was 0.06 (-0.04 to 0.16), and the Pearson correlation coefficient was 0.996. Consequently, we judged the CTD overlap to be acceptable for water temperature.

- Turbidity_NTU (2022 - 2023; n = 809): The Passing-Babcock regression slope was 0.96 (0.95 - 0.98), the intercept was -0.37 (-0.59 to -0.25), and the Pearson correlation coefficient was 0.833. While the slope was significantly different from 1, this difference was small. Plots of residuals showed no patterns. Consequently, we judged the CTD overlap to be acceptable for turbidity.

- SpCond_uScm (2022 - 2023; 790): The Passing-Babcock regression slope was 0.98 (0.98 - 0.99), the intercept was 0.71 (0.53 to 0.87), and the Pearson correlation coefficient was 0.958. While the slope was significantly different from 1, this difference was small. Plots of residuals showed no patterns. Consequently, we judged the CTD overlap to be acceptable for specific conductivity.

- Cond_uScm (2022 - 2023; n = 790): The Passing-Babcock regression slope was 0.98 (0.97 - 0.98), the intercept was 0.69 (0.57 to 0.87), and the Pearson correlation coefficient was 0.956. While the slope was significantly different from 1, this difference was small. Plots of residuals showed no patterns. Consequently, we judged the CTD overlap to be acceptable for conductivity.

- PAR_umolsm2s (2022 - 2023; n = 1018): The Passing-Babcock regression slope was 0.98 (0.96 - 1.01), the intercept was -0.01 (-0.01 to -0.00), and the Pearson correlation coefficient was 0.793. Deviation between the two CTDs tended to be highest under high PAR conditions. Consequently, we judged the CTD overlap to be acceptable for PAR.

- DO percent sat (2022 - 2023; n = 426): The Passing-Babcock regression slope was 1.11 (1.05 - 1.16), the intercept was 0.27 (0.07 to 0.39), and the Pearson correlation coefficient was 0.936. The slope significantly above 1 suggests that the new CTD (8188) measures slightly higher dissolved oxygen than the old CTD (7809). This could be due to slight fouling. Plots of residuals over concentration showed no pattern. Given the much higher slope, DO percent saturation should be interpreted with caution when comparing between CTDs.

- DO_mgL (2022 - 2023; n = 426): The Passing-Babcock regression slope was 1.14 (1.08 - 1.18), the intercept was 0.02 (-0.01 to 0.03), and the Pearson correlation coefficient was 0.939. The slope significantly above 1 suggests that the new CTD (8188) measures slightly higher dissolved oxygen than the old CTD (7809). This could be due to slight fouling. Plots of residuals over concentration showed no pattern. Given the much higher slope, DO concentration should be interpreted with caution when comparing between CTDs.

- Chla_ugL (2022 - 2023; n = 809): The Passing-Babcock regression slope was 0.74 (0.73 - 0.75), the intercept was -0.15 (-0.20 to -0.12), and the Pearson correlation coefficient was 0.928. The slope below 1 suggests that the new CTD (8188) measures slightly lower chlorophyll then the old CTD (7809). This could be due to the slight difference in timing and position of the casts. Given the much higher slope, chlorophyll a should be interpreted with caution when comparing between CTDs.

The serial number of the CTD used for each profile is indicated in the column SN in published data.

Below we note changes in the CTD software, sensor versions, and provide links to the accompanying instrument manuals.

### CTD serial number 4397 ###

Seacat 19Plus V 1.6 - SERIAL NO. 4397 (2013 - 2016)

SBE 43 Dissolved Oxygen Sensor - SERIAL NO. 0434 (2013 - 2016, then transferred to CTD serial number 7809)

Wetlab ECO FLNTU sensor for turbidity and chlorophyll - SERIAL NO. 2496 (2013 - 2016, then transferred to CTD serial number 7809)

### CTD serial number 7809 ###

Sea-Bird SBE19Plus V2 - SERIAL NO. 7809 (2017 - current)

SBE 43 Dissolved Oxygen Sensor - SERIAL NO. 0434 (2013 - current)

Wetlab ECO FLNTU sensor for turbidity and chlorophyll - SERIAL NO. 2496 (2013 - current)

pH and Oxidation Reduction Potential Sensor - SERIAL NO. 0363 (2017 - current). Probe replaced in 2022

Photosynthetically Active Radiation (PAR) Sensor - SERIAL NO. 1122 (2017 - current)

### CTD serial number 8188 ###

Sea-Bird SBE19Plus V2 - SERIAL No. 8188

SBE 43 Dissolved Oxygen Sensor - SERIAL NO. 4269 (2022 - current)

Photosynthetically Active Radiation (PAR) Sensor - SERIAL NO. 2209 (2022 - current)

Wetlab ECO FLNTU sensor for turbidity and chlorophyll - SERIAL NO. FLNTU-7096 (2022 - current)

Wetlab ECO Triplet Scattering Fluorescence for CDOM, phycocyanin, and phycoerythrin- SERIAL NO. FL3-7350 (2022 - current)

References:

Potapov S, Model F, Schuetzenmeister A, Manuilova E, Dufey F, Raymaekers J (2023). _mcr: Method Comparison Regression_. R package version 1.3.2, <https://CRAN.R-project.org/package=mcr>.

Passing, H., and Bablok. 1983. A new biometrical procedure for testing the equality of measurements from two different analytical methods. Application of linear regression procedures for method comparison studies in clinical chemistry, Part I. Journal of Clinical Chemistry and Clinical Biochemistry 21:709-720.

Additional Notes

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.

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: Adrienne Breef-Pilz
Organization:Virginia Tech
Email Address:
abreefpilz@vt.edu
Id:https://orcid.org/0000-0002-6759-0063
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:
2013-03-07
End:
2023-12-04
Geographic Region:
Description:Beaverdam Reservoir is located in Vinton, Virginia, USA
Bounding Coordinates:
Northern:  37.322865Southern:  37.311961
Western:  -79.824834Eastern:  -79.813848
Geographic Region:
Description:Carvins Cove Reservoir is located in Roanoke, Virginia, USA
Bounding Coordinates:
Northern:  37.409127Southern:  37.365345
Western:  -79.978642Eastern:  -79.944052
Geographic Region:
Description:Falling Creek Reservoir is located in Vinton, Virginia, USA
Bounding Coordinates:
Northern:  37.309589Southern:  37.30266
Western:  -79.839249Eastern:  -79.836009
Geographic Region:
Description:Gatewood Reservoir is located in Pulaski, Virginia, USA
Bounding Coordinates:
Northern:  37.054358Southern:  37.03819
Western:  -80.89188Eastern:  -80.858492
Geographic Region:
Description:Spring Hollow Reservoir is located in Salem, Virginia, USA
Bounding Coordinates:
Northern:  37.231092Southern:  37.217594
Western:  -80.179076Eastern:  -80.170407

Project

Parent Project Information:

Title:N/A
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 N/A
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 DEB-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 DBI-1933016
Related Project:
Title:Collaborative Research: CIBR: Cyberinfrastructure Enabling End-to-End Workflows for Aquatic Ecosystem Forecasting
Personnel:
Individual: Renato J. Figueiredo
Organization:Virginia Tech
Email Address:
renato@ece.ufl.edu
Id:https://orcid.org/0000-0001-8835-4476
Role:Principal Investigator
Funding: National Science Foundation DBI-1933016
Related Project:
Title:LTREB: Integrating real-time open data pipelines and forecasting to quantify ecosystem predictability at day to decadal scales
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 DEB-2327030
Related Project:
Title:Collaborative Research: URoL:ASC: Applying rules of life to forecast emergent behavior of phytoplankton and advance water quality management
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 DEB-2318861

Maintenance

Maintenance:
Description:ongoing
Frequency:

Additional Info

Additional Information:
 

Contributions to the 2023 revision:

CCC developed and led the reservoir monitoring program 2013-present, and oversaw CTD purchasing, use, and maintenance throughout this time. ASL developed the QAQC script, visual inspection script, and maintenance log, and contributed to fieldwork in 2023. ABP led the field crew, contributed substantially to fieldwork, maintained the instruments, and processed data in 2023.

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 and the Reservoir Group for contributing to fieldwork; Austin Delany for assisting with the development and maintenance of workflows and QAQC; and Kathryn Hoffman for constructive review.

Other Metadata

Additional Metadata

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        |     |     |     |  \___attribute 'parentSI' = 'siemenPerMeter'
        |     |     |     |  \___attribute 'unitType' = 'conductance'
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        |     |     |     |  \___attribute 'unitType' = 'arealMassDensityRate'
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        |     |     |     |     |___text 'Micromole per meter squared per second'
        |     |     |     |___text '\n            '
        |     |     |___text '\n            '
        |     |     |___element 'unit'
        |     |     |     |  \___attribute 'id' = 'nephelometricTurbidityUnit'
        |     |     |     |  \___attribute 'multiplierToSI' = ''
        |     |     |     |  \___attribute 'name' = 'nephelometricTurbidityUnit'
        |     |     |     |  \___attribute 'parentSI' = ''
        |     |     |     |  \___attribute 'unitType' = 'turbidity'
        |     |     |     |___text '\n               '
        |     |     |     |___element 'description'
        |     |     |     |     |___text 'Nephelometric turbidity unit'
        |     |     |     |___text '\n            '
        |     |     |___text '\n         '
        |     |___text '\n      '
        |___text '\n   '

Additional Metadata

additionalMetadata
        |___text '\n      '
        |___element 'metadata'
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        |     |     |___text '\n            '
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        |     |     |     |___text 'EMLassemblyline'
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        |     |     |     |___text '3.5.5'
        |     |     |___text '\n         '
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