uid=MCM,o=EDI,dc=edirepository,dc=org all public read Nutrients (NH4 - NO3 - NO2 - PO4) John Priscu jpriscu@montana.edu https://orcid.org/0000-0001-5807-6364 McMurdo Dry Valleys LTER http://mcmlter.org/ Kathleen Welch kathleen.welch@colorado.edu https://orcid.org/0000-0003-1028-3086 lab 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 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 2022-03-18 English

An important part of the McMurdo Long Term Ecological Research (LTER) project is identifying patterns and movements of nutrients in perennial ice-covered lakes. This dataset addresses this core area of research and quantifies macronutrient concentrations (NH4+, NO3-, NO2, SRP) found at specific depths in McMurdo Dry Valley lakes.

ammonia lake limnology nitrate nitrite nutrient phosphorus Station Keywords inorganic nutrients LTER Core Areas Data contained in these files has been subjected to quality control standards imposed by the investigator. The user of this data should be aware that, while efforts have been taken to ensure that these data are of the highest quality, there is no guarantee of perfection for the data contained herein and the possibility of errors exists. If you encounter questionable data, please contact the MCM LTER data manager corrected or qualified. Thus, these data may be modified and future data will be appended.

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/macronutrient-concentrations-nh4-no3-no2-po4-lakes 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 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 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 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 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 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 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 1993-10-27 2020-01-11 Data and metadata were improved for compliance with mandates and standards for LTER during 2014.     Data and metadata were offered through the DEIMS system since 2015 (San Gil)    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 Metanut9697.rtf and Metanut9798.rtf files. The files were called up using Microsoft Word version 6.0. Text from these files was used to create this page in html format. McMurdo Dry Valleys LTER Information Manager im@mcmlter.org McMurdo Dry Valleys LTER http://mcmlter.org/ McMurdo Dry Valleys LTER

Lake water samples are collected at specific depths with a five-liter Niskin bottle during normal LTER limnological sampling.  Sub-samples for nutrient analysis are decanted into a 1 L amber Nalgene bottle.  One 100 mL sub-sample is taken from the one-liter amber Nalgene bottle.  The sample is filtered through a combusted (475 degree centigrades for 4 hours) and acidified (the acidification step began with the 2008-2009 season) Whatman 25 mm GF/F using a bell jar apparatus. The filter is used for chlorophyll-a analysis.  The filtrate is collected in a 125 mL acid washed Nalgene bottle and stored at -20 degrees centigrades until analysis  at the Crary Analytical Lab.  Nutrient assays are performed with a Lachat Quickchem AE Autoanalyzer using standard methods.  Ammonia is analyzed using the phenol hypochlorite method.  Nitrite is determined by diazotization with sulfanilamide  and NED. Nitrate is determined by reducing nitrate to nitrite by passing a sample through a copperized cadmium column and analyzing for nitrite, which yields nitrate + nitrite (N+N) concentration. The nitrate concentration is determined by subtracting the nitrite concentration from the N+N concentration.  Soluble  Reactive Phosphorus is determined using ammonium molybdate methods.  Lakes Fryxell, Miers and Hoare are analyzed with a Lachat Quickchem Autoanalyzer.  East and West Lobes of Lake Bonney are analyzed manually (spectrophotometrically) using a 5cm cuvette.   Methods and Notes for 2011-2012 season samples: Samples from the 2011-2012 season were analyzed by Skalar San++ CFA at The Ohio State University. Ammonia was analyzed using a salicylate method. Nitrite was determined by diazotization with sulfanilamide and NED. Nitrate was determined by reducing nitrate to nitrite by passing a sample through a copperized cadmium column and analyzing for nitrite, which yields nitrate + nitrite (N+N) concentration. The nitrate concentration was determined by subtracting the nitrite concentration from the N+N concentration. Soluble Reactive Phosphorus was determined using ammonium molybdate methods. Lakes Miers, Fryxell and Hoare were analyzed with a Skalar CFA instrument. East and West Lobes of Lake Bonney were analyzed manually (spectrophotometrically) using a 10cm cuvette. Method Detection Limit (MDL) and dilutions are listed in the data file for each sample. All values were reported with 2 decimal places for informational purposes; 1 decimal place is significant for N analytes, except for values over 100, for which no decimal places are significant; 2 decimal places are significant for P, except for values over 10, for which 1 decimal place is significant.  

LIMNO_NUTRIENTS Details about the nutrients lake data container: column definitions, units and codes used, etc. mcmlter-lake-nutrients-20220317.csv 1075118 1 1 \n column , " https://mcm.lternet.edu/sites/default/files/data/mcmlter-lake-nutrients-20220317.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 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 NH4 (uM) NH4 (microM) Ammonia concentration found using Lachat microM 0.1 real 0 2000 Null None given NH4(MCM)(uM) NH4(MCM) (microM) Ammonia concentration found using manual methods microM 0.1 real 0 500 Null None given NH4 Comments NH4 Comments Helpful hints about the NH4 sample string Helpful hints about the NH4 sample SRP (uM) SRP (microM) Soluble reactive phosphorus found using Lachat microM 0.01 real 0 100 Null None given SRP(MCM)(uM) SRP(MCM) (microM) Soluble reactive phosphorus found using manual methods microM 0.01 real 0 2 Null None given SRP Comments SRP Comments Helpful hints about the SRP sample string Helpful hints about the SRP sample NO2 (uM) NO2 (microM) Nitrite concentration found using Lachat microM 0.01 real 0 100 Null None given NO2(MCM)(uM) NO2(MCM) (microM) Nitrite concentration found using manual methods microM 0.01 real 0 100 Null None given NO2 Comments NO2 Comments Helpful hints about the NO2 sample string Helpful hints about the NO2 sample NO3 (uM) NO3 (microM) Nitrate concentration found using Lachat microM 0.01 real 0 500 Null None given NO3(MCM)(uM) NO3(MCM) (microM) Nitrate concentration found using manual methods microM 0.01 real 0 300 Null None given NO3 Comments NO3 Comments Helpful hints about the NO3 sample string Helpful hints about the NO3 sample File Name File Name Name of file in which data was submitted string Name of file in which data was submitted Sample Comments Sample Comments notes about the sample string notes about the sample 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