uid=MCM,o=EDI,dc=edirepository,dc=org all public read GLACIER_SUPRA_TRACER Anna Bergstrom annabergstrom@boisestate.edu https://orcid.org/0000-0002-9684-4018 Michael Gooseff michael.gooseff@colorado.edu http://goosefflab.weebly.com https://orcid.org/0000-0003-4322-8315 McMurdo Dry Valleys LTER http://mcmlter.org/ Joel Singley

Institute of Arctic and Alpine Research Boulder CO 80303 US

joel.singley@colorado.edu https://orcid.org/0000-0002-7906-8491 field technician Matthew Cohen mjc@ufl.edu http://sfrc.ifas.ufl.edu/ecohydrology/index.html https://orcid.org/0000-0001-5674-1850 associated researcher 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 2020-02-11 English

This dataset contains a series of grab samples collected from nutrient tracer injection experiments conducted in supraglacial streams on Canada Glacier in Taylor Valley, Antarctica. The purpose of these experiments was to measure potential nutrient uptake in supraglacial stream networks. We chose three reaches and co-injected nutrient tracer(s) and a conservative tracer (NaCl). Tracers were injected at the top of each reach, allowed to mix with the stream water, and move downstream. Grab samples in this dataset were collected at the base of the reach over the course of these tracer experiments, which ran from 14-19 January 2019.

biogeochemistry ice nitrate nutrient cycling streams tracers LTER Controlled Vocabulary Antarctica glacier ice LTER McMurdo Dry Valleys nitrate nutrient phosphorus stream Taylor Valley tracer injection Station Keywords inorganic nutrients LTER Core Areas

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/nutrient-tracer-injection-experiments-supraglacial-streams-canada-glacier-antarctica-january The Canada Glacier a small glacier flowing south-east into the northern side of Taylor Valley.  The glacier receives less than 10 cm of snowfall annually. Its seasonal melting feeds Lake Hoare to the west and Lake Fryxell to the east. 162.894287109375 163.057708740234 -77.598403930664 -77.632133483887 2019-01-14 2019-01-19 McMurdo Dry Valleys LTER Information Manager im@mcmlter.org McMurdo Dry Valleys LTER http://mcmlter.org/ McMurdo Dry Valleys LTER

We performed a series of nutrient tracer experiments in each of the three study reaches over the week of 14-19 January 2019, starting farthest downstream at Reach 2. Three stream reaches were located in the lower Canada Glacier ablation zone of Taylor Valley, Antarctica (Reach 1: -77.62767, 163.96059; Reach 2: -77.6281, 163.957583; Reach 3: -77.629258, 163.964103). Prior to each addition, we collected at least two background samples from both the bottom and top of the study reach. For each experiment, we released known masses of nutrients (N as NaNO3, P as KH2PO43-, and C as glucose) and conservative tracer (NaCl) pre-dissolved in 1 L of stream water as an instantaneous slug at the head of the reach. At the base of the reach, we took grab samples at regular intervals of salt concentration change as measured by a handheld electrical conductivity probe. We analyzed grab samples for NO3-, PO43-, and major ions using an IC located at McMurdo Station. We released only one tracer per day in any given reach to assure all concentrations were fully at background levels before the next tracer experiment. We did a series of tracer injections combining different nutrients: N as NaNO3, N+P (NaNO3 and KH2PO43-), N+P+C (NaNO3, KH2PO43-, and glucose). We had deteriorating weather over the course of the six days in which we conducted tracer experiments. A 24 hour period of clouds and low temperatures caused the smaller upper reaches to freeze such that we were not able to conduct the N+P+C tracer on reaches 1 and 3. We instead moved back down to reach 2, which had low, but adequate, discharge to conduct an N+C tracer experiment. Data were analyzed using methods outlined in Covino et al., 2010 to calculate N and P uptake rates. 

GLACIER_SUPRA_TRACER Supraglacial Stream Tracer Experiment GLACIER_SUPRA_TRACER.csv 17194 1 column , " https://mcm.lternet.edu/sites/default/files/data/GLACIER_SUPRA_TRACER.csv 2019-01-14 2019-01-19 DATASET_CODE Dataset code Internal dataset code. string Internal dataset code. INDEX_CODE Index code Internal lab code / unique identifier. string Internal lab code / unique identifier. REACH Reach Reach in which the experiment was conducted. string Reach in which the experiment was conducted. SAMPLE Sample Sample number/name within the experiment, where BG is a background sample, "Bottom" is the end of the reach, "Top" is the start of the reach. Numeric samples are collected during the tracer experiment. string Sample number/name within the experiment, where BG is a background sample, "Bottom" is the end of the reach, "Top" is the start of the reach. Numeric samples are collected during the tracer experiment. INJECTION Injection Nutrient(s) used in the specific experiment, where N is nitrogen, P is phosphorus, C is carbon. E.g., N+P indicates both nitrogen and phosphorous were injected. string Nutrient(s) used in the specific experiment, where N is nitrogen, P is phosphorus, C is carbon. E.g., N+P indicates both nitrogen and phosphorous were injected. DATE_TIME Date and time Date and time when sample was collected (GMT+13). date DD/MM/YYYY HH:MM:SS CL_MG_L Chloride concentration Chloride (Cl) concentration in the sample. milligramsPerLiter real BLANK missing N-NO3_MG_L Nitrogen (as nitrate) concentration Nitrogen (N-NO3) concentration in the sample. Any value of 0 is below the detection limit of the instrument. milligramsPerLiter real BLANK missing P-PO4_MG_L Phosphorus concentration Phosphorus (P-PO4) concentration in the sample. Any value of 0 is below the detection limit of the instrument. milligramsPerLiter real BLANK missing SO4_MG_L Sulfate concentration Sulfate (SO4) concentration in the sample. milligramsPerLiter real BLANK missing NA_MG_L Sodium concentration Sodium (Na) concentration in the sample. milligramsPerLiter real BLANK missing K_MG_L Potassium concentration Potassium (K) concentration in the sample. milligramsPerLiter real BLANK missing MG_MG_L Magnesium concentration Magnesium (Mg) concentration in the sample. milligramsPerLiter real BLANK missing CA_MG_L Calcium concentration Calcium (Ca) concentration in the sample. milligramsPerLiter real