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LIMNO_CHEMISTRY
Ion concentrations in discrete water column samples collected from lakes in the McMurdo Dry Valleys, Antarctica (1991-2019, ongoing)
John
Priscu
jpriscu@montana.edu
https://orcid.org/0000-0001-5807-6364
Kathleen
Welch
kathleen.welch@colorado.edu
https://orcid.org/0000-0003-1028-3086
W. Berry
Lyons
275 Mendenhall Lab
Columbus
OH
43210
US
(614) 688-3241
lyons.142@osu.edu
http://research.bpcrc.osu.edu/EnvironmentalGeochemistry/
https://orcid.org/0000-0002-3143-7251
McMurdo Dry Valleys LTER
http://mcmlter.org/
Renée
Brown
rfbrown@unm.edu
https://orcid.org/0000-0002-4986-7663
data manager
Amy
Chiuchiolo
LRES, 334 Leon Johnson Hall
Bozeman
MT
59717
US
(406) 994-2360
(406) 994-5863
achiuchiolo@montana.edu
former field crew
Inigo
San Gil
Department of Biology, MSC03 2020 University of New Mexico
Albuquerque
NM
87131
US
(505) 277-2625
(505) 277-2541
isangil@lternet.edu
former data manager
2022-02-07
English
As part of the Long Term Ecological Research (LTER) project in the McMurdo Dry Valleys of Antarctica, a systematic aqueous geochemical sampling program has been undertaken. A series of terrestrial water samples have been collected and analyzed for major ion chemistry by ion chromatography. The concentrations of ions cover a wide range of total dissolved solids from fresh to hypersaline lake waters. This dataset shows concentrations of lithium, sodium, potassium, magnesium, calcium, chloride, bromide, silicon, fluoride, SO4, found in various depths of Taylor Valley lakes.
inorganic nutrients
LTER Core Areas
Data Policies
This data package is released under the Creative Commons Attribution 4.0 International License (CC BY 4.0; http://creativecommons.org/licenses/by/4.0/), which allows consumers (hereinafter referred to as “Data Users”) to freely reuse, redistribute, transform, or build on this work (even commercially) so long as appropriate credit is provided. Accordingly, Data Users are required to properly cite this data package in any publications or in the metadata of any derived products that result from its use (in whole or in part). A recommended citation is provided on the summary metadata page associated with this data package in the McMurdo Dry Valleys LTER Data Catalog (https://mcmlter.org/data), and a generic citation may be found on the summary metadata page in the repository where this data package was obtained. When these data contribute significantly to the contents of a publication, Data Users must also acknowledge that data were provided by the NSF-supported McMurdo Dry Valleys Long Term Ecological Research program (OPP-1637708). This data package has been released in the spirit of open scientific collaboration. Hence, Data Users are strongly encouraged to consider consultation, collaboration, and/or co-authorship (as appropriate) with the data package creator(s). Data Users should be aware these data may be actively used by others for ongoing research; thus, coordination may be necessary to prevent duplicate publication. Data Users should also recognize that misinterpretation of data may occur if they are used outside the context of the original study. Hence, Data Users are urged to contact the data package creator(s) if they have any questions regarding methodology or results. While substantial efforts are made to ensure the accuracy of this data package (with all its components), complete accuracy cannot be guaranteed. Periodic updates to this data package may occur, and it is the responsibility of Data Users to check for new versions. This data package is made available “as is” and comes with no warranty of accuracy or fitness for use. The creator(s) of this data package and the repository where these data were obtained shall not be liable for any damages resulting from misinterpretation, use, or misuse of these data. Finally, as a professional courtesy, we kindly request Data Users notify the primary contact referenced in the metadata when these data are used in the production of any derivative work or publication. Notification should include an explanation of how the data were used, along with a digital copy of the derived product(s). Thank you.
https://mcm.lternet.edu/content/ion-concentrations-discrete-water-column-samples-collected-lakes-mcmurdo-dry-valleys
1991-11-21
2019-12-17
Recent Changes On 2014, Inigo San Gil migrated the metadata into the Drupal Ecological Information System to modernize and improve the McMurdo Dry Valleys LTER services. Older Changes As part of a major database clean-up effort, Kathy Welch and Chris Gardner (database manager) decided to remake this entire table in July of 2007. It was found that there were numerous errors in the old table, including numbers in the wrong columns and errors with Si data. Kathy went through the data year-by-year and verified values against her original Excel files. The database table was remade with only mass values (mg/L) for each ion. The database then calculates molar values dynamically when the table is accessed. This table is now accurate a represents the most updated chemistry record for the dry valley lakes. The original iterations of the 'limnchem' file (limnological chemistry data) were created by Kathy Welch, and submitted to the Institute of Arctic and Alpine Research (INSTAAR) in a July 10, 1997 email message. Following discussions between Kathy Welch (who submitted data) and Denise Steigerwald (data manager), it was decided to remove some fields (eg., dilution factor, sample name), and add others (eg. collection site, collection date, comments for each type of measurement) to these files in order to make them more consistent and relational for future references. The resulting files contain the same name, but have 'xls' extensions. (They were altered using Microsoft Excel). Following these revisions, they were imported into Microsoft Access and saved in a table named "Limnological Chemistry 1991-95 (Welch / Lyons)" Because location name, collection date, and depth are all variables for this table, it was possible to combine each of these files in one table. This table was exported as an ascii, text, comma delimited file named "limnchem.dat" and saved in the appropriate directory to make it accessible on the web page. Data for 1998-2000 was submitted to the Data Manager (Kevin Wheeler) as files Limno_IC_9899.xls and Limno_IC_9900.xls.
McMurdo Dry Valleys LTER
Information Manager
im@mcmlter.org
McMurdo Dry Valleys LTER
http://mcmlter.org/
McMurdo Dry Valleys LTER
Lake sampling was carried out by lowering a Niskin bottle through a hole in the ice cover of the lake to specified depths. Samples were then collected in precleaned plastic bottles. Separate aliquots were collected in serum vials for pH and dissolved inorganic carbon (DIC) measurements. Samples were returned to field laboratories for processing and for time-sensitive analyses such as pH. Dedicated sampling equipment for each lake has been important for maintaining the integrity of the samples. For example, the range of Cl- concentration in the investigated lakes varies by more than three orders of magnitude. This carryover between samples becomes a potential problem. Carryover can also be a potential problem during analysis, and therefore analytical blanks are run to monitor this. The initial sample processing was carried out in field laboratories. A 100-ml sample aliquot was filtered for each anion and cation sample. All samples were filtered through 0.4-microm Nucleopore filters, usually within 12h of collection. The cation samples were filtered into acid-washed polyethylene bottles which had been rinsed with DI water, while the anion samples were filtered into DI-washed bottles. The cation samples were acidified by adding 0.5% (v/v) of concentrated HCl. Quality control was maintained by carefully rinsing all filtration apparatus with DI between samples and by processing filtration blanks which were later run as samples. The majority of water chemistry samples were returned to the Crary Laboratory, McMurdo Station, Antarctica, for analysis. Some of the samples were returned to the laboratory at the University of Alabama (pre 2000) or the Ohio State University (post 2000) for analysis owing to time constraints during the field season. DX-300 ion chromatographic system was used for the major ion analyses. The system included a gradient pump module, high-pressure injection valve with a 25-microm sample loop, a Dionex conductivity detector (CDM-3) advanced computer interface and automated sampler. The timed events and data collection were controlled by the Dionex AI-450 chromatography software for Windows. The same ion chromatographic system was used but was switched back and forth between anion and cation configurations. Appropriate dilutions of the stock standards were used to prepare a range of standards for calibration. Owing to the high salt concentrations in many of the samples, dilutions were made before the samples were run. Dilutions ranged from 1:2 for Lake Hoare surface water up to 1:6000 for the Lake Bonney deep water. The samples were diluted by serial dilution, using plastic microbeakers and adjustable pipettors. Replicate and duplicate samples were run daily. Usually, each sample was injected twice and samples from each batch were run in duplicates to check the precision of the dilutions. In almost every case, the relative standard deviation of the duplicates was less than 1%, even with dilutions of 1:6000. In addition, analytical blanks and filtration blanks were analyzed to check the quality control. Dissolved Silica analyses were done with the molybdate blue method. After the 2007-2008 season silica analysis were done on a Skalar nutrient analyzer at the OSU Lake water samples were analyzed in the field laboratories for DIC with an infrared gas analyzer. The DIC data was used with the other major ion data to calculate ionic balances as a further check on the data
About Molar Units The Limnology chemistry table only contains mass units (mg/L) - molar units are calculated on the fly by the Oracle database. Therefore the number of significant figures may not be accurate. Please see the mass units for the appropriate number of significant figures
LIMNO_CHEMISTRY
Limno chemistry
mcmlter-lake-chemistry-20220207.csv
853390
1
1
\n
column
,
"
https://mcm.lternet.edu/sites/default/files/data/mcmlter-lake-chemistry-20220207.csv
DATASET_CODE
DATASET_CODE
Code to designate the table name
string
Code to designate the table name
LIMNO_RUN
Limno Run
Code for lake's sampling location and date
string
Code for lake's sampling location and date
LOCATION NAME
Location Name
Name of lake where measurement was made
string
Name of lake where measurement was made
LOCATION CODE
Location Code
Code for site where measurement was made
string
Code for site where measurement was made
DATE_TIME
Date/time
Date sample was collected
date
mm/dd/yyyy
Required entry
None given
Depth (m)
Depth (m)
Distance below the piezometric water level from which sample was drawn
meter
real
Null
None given
Sample Comments
Sample Comments
General comments about the sample
string
General comments about the sample
Li (mg/L)
Li (mg/L)
mass concentrations
milligramsPerLiter
real
NULLr
None given
Li (mM)
Li (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
Li COMMENTS
Li comments
Comments
string
Comments
Na (mg/L)
Na (mg/L)
mass concentrations
milligramsPerLiter
real
NULL
None given
Na (mM)
Na (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
Na COMMENTS
Na comments
Comments on the Sodium concentration measurement
string
Comments on the Sodium concentration measurement
K (mg/L)
K (mg/L)
mass concentrations
milligramsPerLiter
real
NULL
None given
K (mM)
K (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
K COMMENTS
K comments
Comments on the potassium concentration measurement
string
Comments on the potassium concentration measurement
Mg (mg/L)
Mg (mg/L)
mass concentrations
milligramsPerLiter
real
NULL
None given
Mg (mM)
Mg (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
Mg COMMENTS
Mg comments
Comments on the Magnessium concentration measurement
string
Comments on the Magnessium concentration measurement
Ca (mg/L)
Ca (mg/L)
mass concentrations
milligramsPerLiter
real
NULL
None given
Ca (mM)
Ca (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
Ca COMMENTS
Ca comments
Comments on the Calcium concentration measurements
string
Comments on the Calcium concentration measurements
F (mg/L)
F (mg/L)
mass concentrations
milligramsPerLiter
real
NULLr
None given
F (mM)
F (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
F COMMENTS
F comments
Comments on the concentration of Iron measurement
string
Comments on the concentration of Iron measurement
Cl (mg/L)
Cl (mg/L)
mass concentrations
milligramsPerLiter
real
NULL
None given
Cl (mM)
Cl (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
Cl COMMENTS
Cl comments
Comments on the Chlorine concentration measurements
string
Comments on the Chlorine concentration measurements
Br (mg/L)
Br (mg/L)
mass concentrations
milligramsPerLiter
real
NULL
None given
Br (mM)
Br (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
Br COMMENTS
Br comments
Comments on the concentration of Bromide measurement
string
Comments on the concentration of Bromide measurement
SO4 (mg/L)
SO4 (mg/L)
mass concentrations
milligramsPerLiter
real
NULL
None given
SO4 (mM)
SO4 (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
SO4 COMMENTS
SO4 comments
Comments
string
Comments
Si (mg/L)
Si (mg/L)
mass concentrations
milligramsPerLiter
real
NULL
None given
Si (mM)
Si (mM)
millimolar concentration
millimoles/liter
real
NULL
None given
Si COMMENTS
Si comments
Comments
string
Comments
File Name
File Name
Original file name before entered into database
string
Original file name before entered into database
DEPTH MASL
DEPTH MASL
Depth referred to the Sea level. Distance below Mean Average Sea water level reference from which sample was drawn
meter
1
real