Attributes {
 s {
  EVTNBR {
    Int16 _FillValue 32767;
    Int16 actual_range 19, 235;
    String bcodmo_name "event";
    String description "Event number";
    String long_name "EVTNBR";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/EVTAGFL/";
    String units "unitless";
  }
  DATE {
    String bcodmo_name "date";
    String description "GMT date when rosette cast sampling was started, in format yyyy-mm-dd";
    String long_name "DATE";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/ADATAA01/";
    String time_precision "1970-01-01";
    String units "unitless";
  }
  GMT {
    String bcodmo_name "time";
    String description "GMT time when rosette cast sampling was started, in format HH:MM";
    String long_name "GMT";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/AHMSAA01/";
    String units "unitless";
  }
  time {
    String _CoordinateAxisType "Time";
    Float64 actual_range 1.47363198e+9, 1.47619242e+9;
    String axis "T";
    String bcodmo_name "ISO_DateTime_UTC";
    String description "GMT date and time when rosette cast sampling was started, in ISO8601 format (yyyy-mm-ddTHH:MM:SS)";
    String ioos_category "Time";
    String long_name "ISO Date Time GMT";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/DTUT8601/";
    String source_name "ISO_DateTime_GMT";
    String standard_name "time";
    String time_origin "01-JAN-1970 00:00:00";
    String time_precision "1970-01-01T00:00:00Z";
    String units "seconds since 1970-01-01T00:00:00Z";
  }
  latitude {
    String _CoordinateAxisType "Lat";
    Float64 _FillValue NaN;
    Float64 actual_range -64.921, -60.78;
    String axis "Y";
    String bcodmo_name "latitude";
    Float64 colorBarMaximum 90.0;
    Float64 colorBarMinimum -90.0;
    String description "Position when sampling cast was started in decimal degrees N";
    String ioos_category "Location";
    String long_name "Latitude";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/LATX/";
    String standard_name "latitude";
    String units "degrees_north";
  }
  longitude {
    String _CoordinateAxisType "Lon";
    Float64 _FillValue NaN;
    Float64 actual_range -68.158, -56.659;
    String axis "X";
    String bcodmo_name "longitude";
    Float64 colorBarMaximum 180.0;
    Float64 colorBarMinimum -180.0;
    String description "Position when sampling cast was started in decimal degrees E";
    String ioos_category "Location";
    String long_name "Longitude";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/LONX/";
    String standard_name "longitude";
    String units "degrees_east";
  }
  PLATFORM {
    String bcodmo_name "instrument";
    String description "Rosette system used. TMC_CTD = trace metal CTD rosette";
    String long_name "PLATFORM";
    String units "unitless";
  }
  CASTNBR {
    String bcodmo_name "cast";
    String description "Cast number";
    String long_name "CASTNBR";
    String units "unitless";
  }
  STNNBR {
    Byte _FillValue 127;
    String _Unsigned "false";
    Byte actual_range 1, 24;
    String bcodmo_name "station";
    String description "Station number";
    String long_name "STNNBR";
    String units "unitless";
  }
  BTLNBR {
    Byte _FillValue 127;
    String _Unsigned "false";
    Byte actual_range 1, 15;
    String bcodmo_name "bottle";
    String description "CTD rosette bottle number (NDA = no data available)";
    String long_name "BTLNBR";
    String units "unitless";
  }
  depth {
    String _CoordinateAxisType "Height";
    String _CoordinateZisPositive "down";
    Float64 _FillValue NaN;
    Float64 actual_range 5.0, 3500.0;
    String axis "Z";
    String bcodmo_name "depth";
    Float64 colorBarMaximum 8000.0;
    Float64 colorBarMinimum -8000.0;
    String colorBarPalette "TopographyDepth";
    String description "Sample collection depth below sea surface";
    String ioos_category "Location";
    String long_name "Depth";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/DEPH/";
    String positive "down";
    String standard_name "depth";
    String units "m";
  }
  NO3_NO2 {
    String bcodmo_name "NO3_NO2";
    String description "Concentration of dissolved nitrate+nitrite. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value. Noted as \"bdl\" when result was below detection limit of instrument(s) used.";
    String long_name "NO3 NO2";
    String units "micromoles per liter (uM)";
  }
  NO3_NO2_STDEV {
    String bcodmo_name "NO3_NO2";
    String description "Standard deviation of replicate nitrate+nitrite concentration measurements. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "NO3 NO2 STDEV";
    String units "micromoles per liter (uM)";
  }
  NO3_NO2_pcnt_RSD {
    String bcodmo_name "NO3_NO2";
    String description "Percent relative standard deviation of replicate nitrate+nitrite concentration measurements. Calculated as NO3_NO2_STDEV divided by NO3_NO2 and multiplied by 100. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "NO3 NO2 Pcnt RSD";
    String units "unitless (percent)";
  }
  NO3_NO2_INSTR {
    String bcodmo_name "instrument";
    String description "Notes which instrument was used for nitrate+nitrite measurements. 1 = Lachat 8500 QuickChem, 2 = Technicon AAII, 3 = Both Lachat 8500 QuickChem and Technicon AAII. Noted as \"nda\" when no data available for this sample, no sample analyzed or obviously erroneous data value.";
    String long_name "NO3 NO2 INSTR";
    String units "unitless";
  }
  PO4 {
    String bcodmo_name "PO4";
    String description "Concentration of dissolved reactive phosphate. Noted as \"nda\" when no data available for this sample, no sample analyzed or obviously erroneous data value. Noted as \"bdl\" when result was below detection limit of instrument(s) used.";
    String long_name "PO4";
    String units "micromoles per liter (uM)";
  }
  PO4_STDEV {
    String bcodmo_name "PO4";
    String description "Standard deviation of replicate phosphate concentration measurements. Noted as \"nda\" when no data available for this sample, no sample analyzed or obviously erroneous data value.";
    String long_name "PO4 STDEV";
    String units "micromoles per liter (uM)";
  }
  PO4_pcnt_RSD {
    String bcodmo_name "PO4";
    String description "Percent relative standard deviation of replicate phosphate concentration measurements. Calculated as PO4_STDEV divided by PO4 and multiplied by 100. Noted as \"nda\" when no data available for this sample, no sample analyzed or obviously erroneous data value.";
    String long_name "PO4 Pcnt RSD";
    String units "unitless (percent)";
  }
  PO4_INSTR {
    String bcodmo_name "instrument";
    String description "Notes which instrument was used for phosphate measurements. 1 = Lachat 8500 QuickChem, 2 = Technicon AAII, 3 = Both Lachat 8500 QuickChem and Technicon AAII. Noted as \"nda\" when no data available for this sample, no sample analyzed or obviously erroneous data value.";
    String long_name "PO4 INSTR";
    String units "unitless";
  }
  SiO4 {
    String bcodmo_name "SiO4";
    String description "Concentration of dissolved silicate. Noted as \"nda\" when no data available for this sample, no sample analyzed or obviously erroneous data value. Noted as \"bdl\" when result was below detection limit of instrument(s) used.";
    String long_name "Si O4";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/SLCAAAZX/";
    String units "micromoles per liter (uM)";
  }
  SiO4_STDEV {
    String bcodmo_name "SiO4";
    String description "Standard deviation of replicate silicate concentration measurements. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "Si O4 STDEV";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/SLCAAAZX/";
    String units "micromoles per liter (uM)";
  }
  SiO4_pcnt_RSD {
    String bcodmo_name "SiO4";
    String description "Percent relative standard deviation of replicate silicate concentration measurements. Calculated as SiO4_STDEV divided by SiO4 and multiplied by 100. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "Si O4 Pcnt RSD";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/SLCAAAZX/";
    String units "unitless (percent)";
  }
  SiO4_INSTR {
    String bcodmo_name "instrument";
    String description "Notes which instrument was used for silicate measurements. 1 = Lachat 8500 QuickChem, 2 = Technicon AAII, 3 = Both Lachat 8500 QuickChem and Technicon AAII. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "Si O4 INSTR";
    String units "unitless";
  }
  NO2 {
    String bcodmo_name "NO2";
    String description "Concentration of dissolved nitrite. Noted as \"nda\" when no data available for this sample, no sample analyzed or obviously erroneous data value. Noted as \"bdl\" when result was below detection limit of instrument(s) used.";
    String long_name "NO2";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/NTRIAAZX/";
    String units "micromoles per liter (uM)";
  }
  NO2_STDEV {
    String bcodmo_name "NO2";
    String description "Standard deviation of replicate nitrite concentration measurements. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "NO2 STDEV";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/NTRIAAZX/";
    String units "micromoles per liter (uM)";
  }
  NO2_pcnt_RSD {
    String bcodmo_name "NO2";
    String description "Percent relative standard deviation of replicate nitrite concentration measurements. Calculated as NO2_STDEV divided by NO2 and multiplied by 100. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "NO2 Pcnt RSD";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/NTRIAAZX/";
    String units "unitless (percent)";
  }
  NO2_INSTR {
    String bcodmo_name "instrument";
    String description "Notes which instrument was used for nitrite measurements. 1 = Lachat 8500 QuickChem, 2 = Technicon AAII, 3 = Both Lachat 8500 QuickChem and Technicon AAII. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "NO2 INSTR";
    String units "unitless";
  }
  NH4 {
    String bcodmo_name "Ammonium";
    String description "Concentration of dissolved ammonium. Noted as \"nda\" when no data available for this sample, no sample analyzed or obviously erroneous data value. Noted as \"bdl\" when result was below detection limit of instrument(s) used.";
    String long_name "NH4";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/AMONAAZX/";
    String units "micromoles per liter (uM)";
  }
  NH4_STDEV {
    String bcodmo_name "Ammonium";
    String description "Standard deviation of replicate ammonium concentration measurements. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "NH4 STDEV";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/AMONAAZX/";
    String units "micromoles per liter (uM)";
  }
  NH4_pcnt_RSD {
    String bcodmo_name "Ammonium";
    String description "Percent relative standard deviation of replicate ammonium concentration measurements. Calculated as NH4_STDEV divided by NH4 and multiplied by 100. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "NH4 PCNT RSD";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/AMONAAZX/";
    String units "unitless (percent)";
  }
  NH4_INSTR {
    String bcodmo_name "instrument";
    String description "Notes which instrument was used for ammonium measurements. 1 = Lachat 8500 QuickChem, 2 = Technicon AAII, 3 = Both Lachat 8500 QuickChem and Technicon AAII. Noted as \"nda\" when no data available for this sample, no sample analyzed, or obviously erroneous data value.";
    String long_name "NH4 INSTR";
    String units "unitless";
  }
 }
  NC_GLOBAL {
    String access_formats ".htmlTable,.csv,.json,.mat,.nc,.tsv,.esriCsv,.geoJson,.odvTxt";
    String acquisition_description "Sampling and analytical procedures:  
 Depth profile samples were collected in September and October 2016 aboard
the R/V/I/B Nathanial B. Palmer using a SeaBird GEOTRACES style SBE32 rosette
system deployed on a conducting Kevlar line with OceanTestEquipment, Inc.
X-Niskin samplers modified for trace element sampling. Samples for
macronutrients were filtered through 0.2 um Pall Acropak membrane filter
capsules and collected in 50 mL Falcon tubes that had been rinsed with
distilled water (DIW), soaked overnight in 10% hydrocholoric acid (HCl,
Fisher, Trace Metal Grade), rinsed three times with DIW again, dried and
rinsed three times with sample prior to filling. Samples were analyzed
shipboard, typically within 24 hours, for nitrate+nitrite, phosphate,
silicate, and occasionally nitrite. Until analyzed shipboard, samples were
stored sealed at 4 \\u00baC in the dark and, following analyses, samples were
frozen at -20 \\u00baC and shipped back to the University of South Florida for
laboratory-based analyses of nitrite, ammonium, and in some cases
nitrate+nitrite, phosphate and silicate again.
 
Analytical methodology was based on established methods (Parsons 1984; Gordon
et al. 1993) as described for the Lachat 8500 QuickChem in the Lachat
QuickChem methods manuals and for the Technicon AAII in the CARIACO methods
manual. All labware were either glass or high density polyethylene and were
cleaned by an initial distilled water (DIW) rinse, followed by an overnight
10% hydrochloric acid (Fisher, Trace Metal Grade) soak, then rinsed three
times with DIW and three times with solvent, analyte or sample prior to fill.
Dedicated glassware was used for reagents and standards to avoid cross
contamination issues. All reagents were made in high purity Milli-Q (>18
M\\u03a9 cm) water.
 
An artificial seawater matrix was used as the carrier for the analyses on the
Lachat QuickChem 8500 at sea and on the Technicon AAII in the lab. 4L batches
of artificial seawater were made by dissolving pre-weighed salts (128.50 g
NaCl, 28.50 g MgSO4*7H2O, 0.6714 g NaHCO3) in Milli-Q to match Southern Ocean
seawater salinity and adjusted to match Southern Ocean seawater pH with 10%
hydrochloric acid.
 
Five-point standard curves were analyzed in duplicate at the beginning and end
of each run with duplicate reagent blanks, and quality control checks every
seventh sample. Quality control check consisted of either an international
reference sample or a quality control sample. The certified nutrient reference
samples used, lots CC and CD, were purchased from Kanso Technos in Osaka,
Japan. The quality control sample was made from a 20-L homogenized surface
Southern Ocean filtered and autoclaved seawater sample. The midpoint standard
from the calibration curve was also analyzed every fourteenth sample to check
for drift during the runs.
 
Detection limits for all five parameters on the two instruments used were
determined from three times the standard deviation of replicate artificial
seawater blanks (n>6). On the Lachat QuickChem 8500, limits of detection were
0.01 uM for nitrate+nitrite, 0.02 uM for phosphate, 0.03 uM for silicate, 0.05
uM for nitrite and 0.5 uM for ammonium. On the Technicon AAII, limits of
detection were 0.06 uM for nitrate+nitrite, 0.02 uM for phosphate, 0.2 uM for
silicate, 0.01 uM for nitrite, and 0.05 uM for ammonium.
 
Sample analyses for macronutrients were performed by William Abbott (USF).
 
Gordon, L.I., Jennings, J., J.C., Ross, A.A. and Krest, J.M., 1993. A
suggested protocol for continuous flow automated analysis of seawater
nutrients (phosphate, nitrate, nitrite and silicic acid) in the WOCE
Hydrographic Program and the Joint Global Ocean Fluxes Study, Methods Manual
WHPO 91-1. WOCE Hydrographic Program Office.
 
Parsons, T.R., Maita, Y. and Lalli, C.M., 1984. A manual of chemical and
biological methods for seawater analysis. Pergammon Press, Oxford, 173 pp.";
    String awards_0_award_nid "738581";
    String awards_0_award_number "OPP-1443483";
    String awards_0_data_url "http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=1443483";
    String awards_0_funder_name "NSF Office of Polar Programs (formerly NSF PLR)";
    String awards_0_funding_acronym "NSF OPP";
    String awards_0_funding_source_nid "713360";
    String awards_0_program_manager "Jennifer Burns";
    String awards_0_program_manager_nid "50508";
    String awards_1_award_nid "738586";
    String awards_1_award_number "OPP-1443474";
    String awards_1_data_url "https://www.nsf.gov/awardsearch/showAward?AWD_ID=1443474";
    String awards_1_funder_name "NSF Office of Polar Programs (formerly NSF PLR)";
    String awards_1_funding_acronym "NSF OPP";
    String awards_1_funding_source_nid "713360";
    String awards_1_program_manager "Jennifer Burns";
    String awards_1_program_manager_nid "50508";
    String awards_2_award_nid "738588";
    String awards_2_award_number "OPP-1443646";
    String awards_2_data_url "https://www.nsf.gov/awardsearch/showAward?AWD_ID=1443646";
    String awards_2_funder_name "NSF Office of Polar Programs (formerly NSF PLR)";
    String awards_2_funding_acronym "NSF OPP";
    String awards_2_funding_source_nid "713360";
    String awards_2_program_manager "Jennifer Burns";
    String awards_2_program_manager_nid "50508";
    String cdm_data_type "Other";
    String comment "NBP16-08 Station Nutrients 
  PI: Kristen Buck (USF) 
  Co-PIs: Bethany Jenkins (URI) & P. Dreux Chappell (Old Dominion) 
  Version date: 30 July 2018";
    String Conventions "COARDS, CF-1.6, ACDD-1.3";
    String creator_email "info@bco-dmo.org";
    String creator_name "BCO-DMO";
    String creator_type "institution";
    String creator_url "https://www.bco-dmo.org/";
    String data_source "extract_data_as_tsv version 2.3  19 Dec 2019";
    String date_created "2018-07-30T16:47:11Z";
    String date_modified "2020-01-03T17:17:18Z";
    String defaultDataQuery "&time<now";
    String doi "10.1575/1912/bco-dmo.742819.1";
    Float64 Easternmost_Easting -56.659;
    Float64 geospatial_lat_max -60.78;
    Float64 geospatial_lat_min -64.921;
    String geospatial_lat_units "degrees_north";
    Float64 geospatial_lon_max -56.659;
    Float64 geospatial_lon_min -68.158;
    String geospatial_lon_units "degrees_east";
    Float64 geospatial_vertical_max 3500.0;
    Float64 geospatial_vertical_min 5.0;
    String geospatial_vertical_positive "down";
    String geospatial_vertical_units "m";
    String history "2024-11-05T14:49:14Z (local files)
2024-11-05T14:49:14Z https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_742819.das";
    String infoUrl "https://www.bco-dmo.org/dataset/742819";
    String institution "BCO-DMO";
    String instruments_0_acronym "FIA";
    String instruments_0_dataset_instrument_description "Lachat QuickChem 8500 series 2, 4 channel analyzer";
    String instruments_0_dataset_instrument_nid "743114";
    String instruments_0_description "An instrument that performs flow injection analysis. Flow injection analysis (FIA) is an approach to chemical analysis that is accomplished by injecting a plug of sample into a flowing carrier stream. FIA is an automated method in which a sample is injected into a continuous flow of a carrier solution that mixes with other continuously flowing solutions before reaching a detector. Precision is dramatically increased when FIA is used instead of manual injections and as a result very specific FIA systems have been developed for a wide array of analytical techniques.";
    String instruments_0_instrument_external_identifier "https://vocab.nerc.ac.uk/collection/L05/current/LAB36/";
    String instruments_0_instrument_name "Flow Injection Analyzer";
    String instruments_0_instrument_nid "657";
    String instruments_0_supplied_name "Lachat QuickChem 8500";
    String instruments_1_acronym "Technicon AutoAnalyzerII";
    String instruments_1_dataset_instrument_description "Technicon AAII";
    String instruments_1_dataset_instrument_nid "743115";
    String instruments_1_description "A rapid flow analyzer that may be used to measure nutrient concentrations in seawater. It is a continuous segmented flow instrument consisting of a sampler, peristaltic pump, analytical cartridge, heating bath, and colorimeter. See more information about this instrument from the manufacturer.";
    String instruments_1_instrument_external_identifier "https://vocab.nerc.ac.uk/collection/L22/current/TOOL0291/";
    String instruments_1_instrument_name "Technicon AutoAnalyzerII";
    String instruments_1_instrument_nid "473306";
    String instruments_1_supplied_name "Technicon AAII";
    String keywords "ammonium, bco, bco-dmo, biological, btlnbr, castnbr, chemical, data, dataset, date, depth, deviation, dmo, erddap, evtnbr, GMT, instr, iso, latitude, longitude, management, nh4, NH4_INSTR, NH4_pcnt_RSD, NH4_STDEV, nitrate, nitrite, no2, NO2_INSTR, NO2_pcnt_RSD, NO2_STDEV, no3, NO3_NO2, NO3_NO2_INSTR, NO3_NO2_pcnt_RSD, NO3_NO2_STDEV, oceanography, office, pcnt, phosphate, platform, po4, PO4_INSTR, PO4_pcnt_RSD, PO4_STDEV, preliminary, rsd, SiO4, SiO4_INSTR, SiO4_pcnt_RSD, SiO4_STDEV, standard, standard deviation, stdev, stnnbr, time";
    String license "https://www.bco-dmo.org/dataset/742819/license";
    String metadata_source "https://www.bco-dmo.org/api/dataset/742819";
    Float64 Northernmost_Northing -60.78;
    String param_mapping "{'742819': {'ISO_DateTime_GMT': 'flag - time', 'LATITUDE': 'flag - latitude', 'DEPTH': 'flag - depth', 'LONGITUDE': 'flag - longitude'}}";
    String parameter_source "https://www.bco-dmo.org/mapserver/dataset/742819/parameters";
    String people_0_affiliation "University of South Florida";
    String people_0_affiliation_acronym "USF";
    String people_0_person_name "Kristen N. Buck";
    String people_0_person_nid "51624";
    String people_0_role "Principal Investigator";
    String people_0_role_type "originator";
    String people_1_affiliation "Old Dominion University";
    String people_1_affiliation_acronym "ODU";
    String people_1_person_name "Phoebe Dreux Chappell";
    String people_1_person_nid "636572";
    String people_1_role "Co-Principal Investigator";
    String people_1_role_type "originator";
    String people_2_affiliation "University of Rhode Island";
    String people_2_affiliation_acronym "URI";
    String people_2_person_name "Bethany D. Jenkins";
    String people_2_person_nid "558172";
    String people_2_role "Co-Principal Investigator";
    String people_2_role_type "originator";
    String people_3_affiliation "University of South Florida";
    String people_3_affiliation_acronym "USF";
    String people_3_person_name "Kristen N. Buck";
    String people_3_person_nid "51624";
    String people_3_role "Contact";
    String people_3_role_type "related";
    String people_4_affiliation "Woods Hole Oceanographic Institution";
    String people_4_affiliation_acronym "WHOI BCO-DMO";
    String people_4_person_name "Shannon Rauch";
    String people_4_person_nid "51498";
    String people_4_role "BCO-DMO Data Manager";
    String people_4_role_type "related";
    String project "Diatom_Bacteria_Ligands";
    String projects_0_acronym "Diatom_Bacteria_Ligands";
    String projects_0_description "This project focuses on an important group of photosynthetic algae in the Southern Ocean (SO), diatoms, and the roles associated bacterial communities play in modulating their growth. Diatom growth fuels the SO food web and balances atmospheric carbon dioxide by sequestering the carbon used for growth to the deep ocean on long time scales as cells sink below the surface. The diatom growth is limited by the available iron in the seawater, most of which is not freely available to the diatoms but instead is tightly bound to other compounds. The nature of these compounds and how phytoplankton acquire iron from them is critical to understanding productivity in this region and globally. The investigators will conduct experiments to characterize the relationship between diatoms, their associated bacteria, and iron in open ocean and inshore waters. Experiments will involve supplying nutrients at varying nutrient ratios to natural phytoplankton assemblages to determine how diatoms and their associated bacteria respond to different conditions. This will provide valuable data that can be used by climate and food web modelers and it will help us better understand the relationship between iron, a key nutrient in the ocean, and the organisms at the base of the food web that use iron for photosynthetic growth and carbon uptake. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The project supports early career senior investigators and the training of graduate and undergraduate students as well as outreach activities with middle school Girl Scouts in Rhode Island, inner city middle and high school age girls in Virginia, and middle school girls in Florida.
The project combines trace metal biogeochemistry, phytoplankton cultivation, and molecular biology to address questions regarding the production of iron-binding compounds and the role of diatom-bacterial interactions in this iron-limited region. Iron is an essential micronutrient for marine phytoplankton. Phytoplankton growth in the SO is limited by a lack of sufficient iron, with important consequences for carbon cycling and climate in this high latitude regime. Some of the major outstanding questions in iron biogeochemistry relate to the organic compounds that bind >99.9% of dissolved iron in surface oceans. The investigators' prior research in this region suggests that production of strong iron-binding compounds in the SO is linked to diatom blooms in waters with high nitrate to iron ratios. The sources of these compounds are unknown but the investigators hypothesize that they may be from bacteria, which are known to produce such compounds for their own use. The project will test three hypotheses concerning the production of these iron-binding compounds, limitations on the biological availability of iron even if present in high concentrations, and the roles of diatom-associated bacteria in these processes. Results from this project will provide fundamental information about the biogeochemical trigger, and biological sources and function, of natural strong iron-binding compound production in the SO, where iron plays a critical role in phytoplankton productivity, carbon cycling, and climate regulation.";
    String projects_0_end_date "2019-06";
    String projects_0_geolocation "Southern Ocean, Western Antarctic Peninsula 60-65 S, 63 W";
    String projects_0_name "Collaborative Research: Investigating Iron-binding Ligands in Southern Ocean Diatom Communities: The Role of Diatom-Bacteria Associations";
    String projects_0_project_nid "738582";
    String projects_0_start_date "2015-07";
    String publisher_name "Biological and Chemical Oceanographic Data Management Office (BCO-DMO)";
    String publisher_type "institution";
    String sourceUrl "(local files)";
    Float64 Southernmost_Northing -64.921;
    String standard_name_vocabulary "CF Standard Name Table v55";
    String subsetVariables "PLATFORM,NO2_STDEV,NO2_pcnt_RSD,NH4_STDEV,NH4_pcnt_RSD";
    String summary "Dissolved macronutrient concentrations from depth profiles from RVIB Nathaniel B. Palmer cruise NBP1608 in the Southern Ocean from September to October 2016.";
    String time_coverage_end "2016-10-11T13:27:00Z";
    String time_coverage_start "2016-09-11T22:13:00Z";
    String title "[NBP1608 Station Nutrients] - Dissolved macronutrient concentrations from depth profiles from RVIB Nathaniel B. Palmer cruise NBP1608 in the Southern Ocean from September to October 2016 (Collaborative Research: Investigating Iron-binding Ligands in Southern Ocean Diatom Communities: The Role of Diatom-Bacteria Associations)";
    String version "1";
    Float64 Westernmost_Easting -68.158;
    String xml_source "osprey2erddap.update_xml() v1.3";
  }
}