Anna J. BergstromMichael N. Gooseff 2020-02-11 tabular digitial data McMurdo Dry Valleys LTER McMurdo Dry Valleys LTER 10.6073/pasta/293caa4b1b4c24b7b5b5713500cb5e37 https://mcm.lternet.edu/content/nutrient-tracer-injection-experiments-supraglacial-streams-canada-glacier-antarctica-january 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. 2019-01-14 2019-01-19 ground condition As needed 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. 163.057708740234 162.894287109375 -77.598403930664 -77.632133483887 LTER Core Areas inorganic nutrients None <cntperp> <cntper>McMurdo Dry Valleys LTER Information Manager</cntper> </cntperp> <cntemail>im@mcmlter.org</cntemail> Name: Joel G. Singley Role: field technician Name: Matthew J. Cohen Role: associated researcher Name: Kathleen A. Welch Role: lab technician Name: Renée F. Brown Role: data manager Not Applicable Not Applicable Field and/or Lab Methods 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.  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.  unknown GLACIER_SUPRA_TRACER Supraglacial Stream Tracer Experiment Dataset code Internal dataset code. The data provider Internal dataset code. Index code Internal lab code / unique identifier. The data provider Internal lab code / unique identifier. Reach Reach in which the experiment was conducted. The data provider Reach in which the experiment was conducted. 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. The data provider 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 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. The data provider 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 and time Date and time when sample was collected (GMT+13). The data provider calendar date/time DD/MM/YYYY HH:MM:SS gregorian calendar Chloride concentration Chloride (Cl) concentration in the sample. The data provider milligramsPerLiter Nitrogen (as nitrate) concentration Nitrogen (N-NO3) concentration in the sample. Any value of 0 is below the detection limit of the instrument. The data provider milligramsPerLiter Phosphorus concentration Phosphorus (P-PO4) concentration in the sample. Any value of 0 is below the detection limit of the instrument. The data provider milligramsPerLiter Sulfate concentration Sulfate (SO4) concentration in the sample. The data provider milligramsPerLiter Sodium concentration Sodium (Na) concentration in the sample. The data provider milligramsPerLiter Potassium concentration Potassium (K) concentration in the sample. The data provider milligramsPerLiter Magnesium concentration Magnesium (Mg) concentration in the sample. The data provider milligramsPerLiter Calcium concentration Calcium (Ca) concentration in the sample. The data provider milligramsPerLiter McMurdo Dry Valleys LTER The data distributor shall not be liable for innacuracies in the content http 1 0 1 column , https://mcm.lternet.edu/sites/default/files/data/GLACIER_SUPRA_TRACER.csv None 2020-02-11 2020-02-11 McMurdo Dry Valleys LTER http://mcmlter.org/ Biological Data Profile of the Content Standards for Digital Geospatial Metadata devised by the Federal Geographic Data Committee. Drupal Ecological information Management Systems, version D7, Biological Data Profile module