uid=MCM,o=EDI,dc=edirepository,dc=org all public read limncn.dat Cristina Takacs-Vesbach cvesbach@unm.edu http://www.vesbachlab.org https://orcid.org/0000-0002-5535-2201 John Priscu jpriscu@montana.edu https://orcid.org/0000-0001-5807-6364 McMurdo Dry Valleys LTER http://mcmlter.org/ Jade Lawrence jlawrence1@unm.edu https://orcid.org/0009-0005-2603-342X field technician 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 Kathleen Welch kathleen.welch@colorado.edu https://orcid.org/0000-0003-1028-3086 former lab crew Denise Steigerwald former data manager Chris Gardner gardner.177@osu.edu https://orcid.org/0000-0003-0400-3754 former data manager 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 2025-09-28 English

An important part of the McMurdo Long Term Ecological Research (LTER) is evaluating carbon and nitrogen budgets in perennial ice-covered lakes. This dataset addresses this core area of research and quantifies the particulate organic carbon (POC) and nitrogen (PON) found at specific depths in lakes across the McMurdo Dry Valleys of Antarctica.

lakes organic nitrogen particulate organic carbon particulates LTER Controlled Vocabulary Antarctica carbon lake limnology nitrogen organic particulate organic carbon particulate organic nitrogen Station Keywords organic matter LTER Core Areas Funding for this work has been provided by several grants from the US National Science Foundation for Long Term Ecological Research, most recently under award #OPP-2224760.

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-2224760). 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/particulate-organic-carbon-poc-and-nitrogen-pon-concentrations-discrete-water-column-samples Lake Bonney is a saline lake with permanent ice cover at the western end of Taylor Valley in the McMurdo Dry Valleys of Victoria Land, Antarctica. It is 7 kilometres or 4.3 mi long and up to 900 metres or 3,000 ft wide. A narrow channel only 50 metres or 160 ft wide. Lake Bonney at Narrows separates the lake into East Lake Bonney 3.32 square kilometres or 1.28 sq mi and West Lake Bonney, 0.99 square kilometres or 0.38 sq mi. The west lobe is flanked by Taylor glacier. Valley: Taylor Distance to Sea : 25 Maximum Length (km): 4.8 Maximum Width (km): 0.9 Maximum Depth (m): 37 Surface Area (km^2): 3.32 Ice Thickness Average Surface (m): 3 - 4.5 Volume (m^3 * 10^6): 54.7 162.353210449219 162.536209106445 -77.697700500488 -77.724441528320 57 57 meter The Lake Fryxell basin is formed by a moraine depression in a wider portion of the Taylor Valley. It has a number of moraine islands and shallower areas, as well as several relatively well developed deltas. The lake is fed by at least 10 meltwater streams with a total drainage catchment of 230 km2. The lake is dammed to the southwest by the Canada Glacier and is topographically closed. It is perennially ice covered; during summer months, an ice-free moat generally forms around much of the lake margin. Lake levels have risen ~2 m between 1971 and 1996. There are no surface outflows; the only known water loss is through ice ablation (evaporation, sublimation and physical scouring). Valley: Taylor Distance to Sea : 9 Maximum Length (km): 5.8 Maximum Width (km): 2.1 Maximum Depth (m): 20 Surface Area (km^2): 7.08 Ice Thickness Average Surface (m): 3.3 - 4.5 Volume (m^3 * 10^6): 25.2 163.048782348633 163.259582519531 -77.597076416016 -77.622711181641 18 18 meter Lake Hoare occupies a narrower portion of the Taylor Valley, dammed by the Canada Glacier. It would drain almost completely without this dam. There are a number of islands which may be related to an old terminal of Canada Glacier. The lake is fed primarily from direct runoff from the glacier, as well as meltwater streams. (Lake level rose ~1.5 m between 1972 and 1996). There are no surface outflows; the only known water loss is through ice ablation (evaporation, sublimation and physical scouring). Valley: Taylor Distance to Sea : 15 Maximum Length (km): 4.2 Maximum Width (km): 1 Maximum Depth (m): 34 Surface Area (km^2): 1.94 Ice Thickness Average Surface (m): 3.1 - 5.5 Volume (m^3 * 10^6): 17.5 162.784423828125 162.935836791992 -77.623085021973 -77.639259338379 73 73 meter Lake Joyce lies in the Pearse Valley against the Taylor Glacier. Valley: Pearse Distance to Sea : 44 Maximum Length (km): 1 Maximum Width (km): 1 Maximum Depth (m): 35 Surface Area (km^2): 0.83 Ice Thickness Average Surface (m): 3.9 - 5.6 Volume (m^3 * 10^6): 4.9 161.608886718750 161.662445068359 -77.715972900391 -77.726486206055 301 301 meter A lake with an area of 1 square mile which occupies the north portion of Pyramid Trough, Scott Coast. Named by New Zealand Geographic Board (NZGB) (1994) in association with Pyramid Trough. 162.718856811523 162.823226928711 -77.417655944824 -77.442016601563 Lake Miers lies in the Miers Valley. Valley: Miers Distance to Sea : 20 Maximum Length (km): 1.5 Maximum Width (km): 0.7 Maximum Depth (m): 21 Surface Area (km^2): 1.3 Ice Thickness Average Surface (m): 3.4 - 6 Volume (m^3 * 10^6): 2.9 163.812332153320 163.886840820313 -78.094047546387 -78.101478576660 240 240 meter Lake Vanda is located in the Wright Valley, adjacent to the Taylor Valley. It is fed primarily by the Onyx River, which has its origin at Lake Brownworth, and ultimately at the Lower Wright Glacier located ~27 km east of the lake. The lake has no outflow. Valley: Wright Distance to Sea : 47 Maximum Length (km): 8 Maximum Width (km): 2 Maximum Depth (m): 75 Surface Area (km^2): 5.2 Ice Thickness Average Surface (m): 2.8 - 4.2 Volume (m^3 * 10^6): 160 161.391906738281 161.691970825195 -77.518882751465 -77.542304992676 143 143 meter Lake Bonney is a saline lake with permanent ice cover at the western end of Taylor Valley in the McMurdo Dry Valleys of Victoria Land, Antarctica. It is 7 kilometres or 4.3 mi long and up to 900 metres or 3,000 ft wide. A narrow channel only 50 metres or 160 ft wide. Lake Bonney at Narrows separates the lake into East Lake Bonney 3.32 square kilometres or 1.28 sq mi and West Lake Bonney, 0.99 square kilometres or 0.38 sq mi. Valley: Taylor Distance to Sea : 28 Maximum Length (km): 2.6 Maximum Width (km): 0.9 Maximum Depth (m): 40 Surface Area (km^2): 0.99 Ice Thickness Average Surface (m): 2.8-4.5 Volume (m^3 * 10^6): 10.1 162.269104003906 162.354934692383 -77.714805603027 -77.727287292480 57 57 meter 1993-10-27 2024-12-23 Data from this table was submitted to INSTAAR by John Priscu's team at Montana State University. The raw data files listed under 'file name' are the names of the original files submitted. The 1993/94 and 1994/95 datasets are Microsoft Excel version 6.0 files, and the 1995/96, 1996/97 and 1997/98 datasets are ascii text files. Upon arrival at INSTAAR, the data manager fine-tuned the location codes and limno runs to match those provided in the "locations, dates, codes for lake chemistry, biology samples" file. The file was imported into Microsoft Access on INSTAAR's Unix system, and can currently be found there. The file  was then exported in ascii, comma delimited text and MS-DOS text (table layout) to present on the MCM LTER web site. Both of these files are linked to this web page above. Information for the metadata was obtained from the Metachn9697.rtf file. The file was called up using  Microsoft Word version 6.0. Text from this file was used to create this page in html format.   Data for the 2005-6 and 2006-7 season was updated in Oct 2009   Metadata was standardized to EML in 2006, and enhanced in 2014 using the Drupal Ecological Information Management System   In 2020, issues regarding how filter blank corrections were applied to the particulate organic carbon data were identified. The errors applied to the carbon data from the 2003-04 through the 2009-10 austral summer field seasons. All data from this period were re-processed according to the equations in the MCM LTER limno methods manual, and these corrections were applied to this data package in April 2021.   McMurdo Dry Valleys LTER Information Manager im@mcmlter.org McMurdo Dry Valleys LTER http://mcmlter.org/ McMurdo Dry Valleys LTER

Lake water samples were collected at specific depths with a five-liter Niskin bottle during normal LTER limnological sampling. Sub-samples were decanted into three 1 L Nalgene bottles (two light and one amber), two 500 mL amber Nalgene bottles, three 150 mL borosilicate glass bottles, two 20 mL scintillation vials, and one 30 mL serum vial. A 500 mL sample from the one liter amber Nalgene bottle was decanted and filtered through a combusted Whatman 25 mm GF/F filter (475 °C for 4 hours). The filter was placed onto an aluminum weighing pan and air dried. Once the filters were dry, the pans were stacked together and frozen for later analysis.  Filters were acidified with HCL fumes, and analyzed using an Elemental Analyzer (currently a CE Elantech Flash EA 1112 Elemental Analyzer). Total particulate organic carbon (POC) and particulate organic nitrogen (PON) was obtained by comparison with an acetanilide standard curve. Prior to the 0304 season, analysis was done on a 10 mm diameter sub-sample punch of the GF/F filter; from 0304 to present, the entire GF/F filter was analyzed. See the maintenance section for further details regarding data from 2003-04 thru the 2019-20 field seasons. Instrument detection limits for POC and PON are 10 μg punch-1 and 5 μg punch-1 respectively.

LIMNO_POC_PON mcmlter-lake-poc_pon-20250928.csv 516866 1 1 \n column , " https://mcm.lternet.edu/sites/default/files/data/mcmlter-lake-poc_pon-20250928.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 on which sample was gathered date mm/dd/yyyy Depth (m) Depth (m) Distance below the piezometric water level from which sample was drawn. meter 1 real 1 45 Required entry None given POC (ug/L) POC (microg L-1) Particulate organic carbon concentration found at lake depth ug/L 0.1 real 0 3000 Null None given POC (microM) POC (microM) Particulate organic carbon concentration found at lake depth microM 0.1 real 0 200 Null None given POC Comments POC Comments Helpful hints about the POC sample string Helpful hints about the POC sample PON (ug/L) PON (microg L-1) Particulate organic nitrogen concentration found at lake depth ug/L 0.1 real 0 500 Null None given PON (microM) PON (microM) Particulate organic nitrogen concentration found at lake depth microM 0.1 real 0 20 Null None given PON Comments PON Comments Helpful hints about the PON sample string Helpful hints about the PON sample C:N C:N Carbon to Nitrogen Ratio dimensionless 0.1 real Null None given Sample Comments Sample Comments Helpful hints about the overall sample string Helpful hints about the overall sample File Name File Name Name of file in which data was submitted string Name of file in which data was submitted 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