Attributes {
 s {
  Extract {
    String bcodmo_name "sample_descrip";
    String description "Extraction solution";
    String long_name "Extract";
    String units "unitless";
  }
  Step {
    String bcodmo_name "sample_descrip";
    String description "Step in the sequential extraction scheme (1?4)";
    String long_name "Step";
    String units "unitless";
  }
  Dilution {
    String bcodmo_name "treatment";
    String description "Sample dilution or \"None\"";
    String long_name "Dilution";
    String units "unitless";
  }
  Date {
    String bcodmo_name "date";
    String description "Date the samples were analyzed in ISO 8601 format yyyy-mm-dd";
    String long_name "Date";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/ADATAA01/";
    String source_name "Date";
    String time_precision "1970-01-01";
    String units "unitless";
  }
  Sample_ID {
    String bcodmo_name "sample";
    String description "Unique sample identifier";
    String long_name "Sample ID";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P02/current/ACYC/";
    String units "unitless";
  }
  Analyte_Name {
    String bcodmo_name "sample_descrip";
    String description "Element analyzed";
    String long_name "Analyte Name";
    String units "unitless";
  }
  Peak_Concentration {
    Float32 _FillValue NaN;
    Float32 actual_range 0.0184, 73.9;
    String bcodmo_name "PO4";
    String description "Phosphate concentration (uncorrected)";
    String long_name "Peak Concentration";
    String units "micromolar (uM)";
  }
  blank_corrected {
    Float32 _FillValue NaN;
    Float32 actual_range 1.17, 73.85;
    String bcodmo_name "sample_descrip";
    String description "Concentration adjusted after blank";
    String long_name "Blank Corrected";
    String units "unitless";
  }
  Actual_PO4 {
    Float32 _FillValue NaN;
    Float32 actual_range 12.716, 399.2;
    String bcodmo_name "PO4";
    String description "Concentration corrected for dilution";
    String long_name "Mass Concentration Of Phosphate In Sea Water";
    String units "micromolar (uM)";
  }
  P_extracted {
    Float32 _FillValue NaN;
    Float32 actual_range 0.69, 121.16;
    String bcodmo_name "PO4";
    String description "Amount of phosphorus extracted";
    String long_name "P Extracted";
    String units "micromoles (umol)";
  }
  Sed_mass {
    Float32 _FillValue NaN;
    Float32 actual_range 2.4998, 2.51;
    String bcodmo_name "mass_dry";
    String description "Dried sediment mass";
    String long_name "Sed Mass";
    String units "grams (g)";
  }
  PO4 {
    Float32 _FillValue NaN;
    Float32 actual_range 0.28, 48.35;
    String bcodmo_name "PO4";
    String description "Micromoles of phosphorus per gram of sediment (ground dry weight)";
    String long_name "Mass Concentration Of Phosphate In Sea Water";
    String units "micromoles per gram (umol/g)";
  }
  Peak_Area {
    Float32 _FillValue NaN;
    Float32 actual_range -0.0218, 28.0;
    String bcodmo_name "unknown";
    String description "Peak area";
    String long_name "Peak Area";
    String units "volts";
  }
  Peak_Height {
    Float32 _FillValue NaN;
    Float32 actual_range -0.00177, 2.32;
    String bcodmo_name "unknown";
    String description "Peak height";
    String long_name "Peak Height";
    String units "volts";
  }
 }
  NC_GLOBAL {
    String access_formats ".htmlTable,.csv,.json,.mat,.nc,.tsv";
    String acquisition_description "Locations:
 
Arctic Ocean: P-1-94-AR P21, 84\\u00b05' N, 174\\u00b058' W  
 California margin: W-2-98-NC TF1, 41\\u00b05' N, 125\\u00b01' W  
 Equatorial Pacific: TT013-06MC, 12\\u00b000' S, 134\\u00b056' W
 
Methodology:
 
Prior to the extraction, we freeze-dried, ground and sieved sediment samples
to less than 125 \\u03bcm (Ruttenberg 1992). For a given sample, we weighed
four sample replicates (2 g) and placed each in 250 mL HDPE bottles. Sodium
dithionite (F.W. 147.12 g/mol; 7.4 g) was added to each sample split, followed
by 200 mL of citrate-bicarbonate solution (pH 7.6). This step produces
effervescence, so the solution should be added slowly to the sample. We shook
samples for 8 h and then centrifuged them at 3,700 rpm for 15 min. We filtered
the supernatants with a 0.4 \\u03bcm polycarbonate filter. We took 20 mL
aliquots from the filtrate for each sample split for MRP and total P analyses,
and kept them refrigerated until analysis within 24 h. We added 200 mL of
ultrapure water to the solid residue for each sample split as a wash step
after the above reductive step, shook samples for 2 h, and then centrifuged
them at 3,700 rpm for 15 min. We filtered the supernatants with 0.4 \\u03bcm
polycarbonate filters and set aside 20 mL of filtrate from each sample split
for MRP and total P analyses. We then extracted the solid sample residues in
200 mL of sodium acetate buffer (pH 4.0) for 6 h. At the end of this
extraction step, we centrifuged the bottles at 3,700 rpm for 15 min, filtered
the supernatants with 0.4 \\u03bcm polycarbonate filters and took a 20 mL
aliquot of filtrate from each sample split for MRP and total P analyses. We
added 200 mL of ultrapure water to the solid residue for each sample split as
a wash step, shook samples for 2 h, and then centrifuged them at 3,700 rpm for
15 min. We filtered the supernatants with 0.4 \\u03bcm polycarbonate filters
and set aside 20 mL of filtrate from each sample split for MRP and total P
analyses. We repeated the water rinse step, and collected aliquots for MRP and
total P analyses as in the previous steps. The concentrations of MRP were
determined as described below.
 
The MRP concentrations were measured on a QuikChem 8000 automated ion
analyzer. Standards were prepared with the same solutions used for the
extraction step to minimize matrix effects on P measurements. Sediment
extracts and standards (0 30 \\u03bcM PO4) were diluted ten-fold to prevent
matrix interference with color development. The detection limit for P on this
instrument is 0.2 \\u03bcM. We derived MUP concentrations by subtracting MRP
from total P concentrations, which are included in a different dataset.";
    String awards_0_award_nid "554980";
    String awards_0_award_number "OCE-0939564";
    String awards_0_data_url "http://www.nsf.gov/awardsearch/showAward?AWD_ID=0939564";
    String awards_0_funder_name "NSF Division of Ocean Sciences";
    String awards_0_funding_acronym "NSF OCE";
    String awards_0_funding_source_nid "355";
    String awards_0_program_manager "David L. Garrison";
    String awards_0_program_manager_nid "50534";
    String cdm_data_type "Other";
    String comment "MRP sediments with pretreatment 
  PI: Adina Paytan 
  Data Version 1: 2020-04-13";
    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 dataset_current_state "Final and no updates";
    String date_created "2020-02-28T20:30:03Z";
    String date_modified "2020-07-02T21:02:33Z";
    String defaultDataQuery "&time<now";
    String doi "10.26008/1912/bco-dmo.798995.1";
    String history "2024-11-15T12:10:53Z (local files)
2024-11-15T12:10:53Z https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_798995.das";
    String infoUrl "https://www.bco-dmo.org/dataset/798995";
    String institution "BCO-DMO";
    String instruments_0_acronym "FIA";
    String instruments_0_dataset_instrument_nid "799005";
    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 "QuikChem 8000 automated ion analyzer";
    String keywords "Actual_PO4, analyte, Analyte_Name, area, bco, bco-dmo, biological, blank, blank_corrected, chemical, chemistry, concentration, corrected, data, dataset, date, dilution, dmo, earth, Earth Science > Oceans > Ocean Chemistry > Phosphate, erddap, extract, extracted, height, management, mass, mass_concentration_of_phosphate_in_sea_water, name, ocean, oceanography, oceans, office, P_extracted, peak, Peak_Area, Peak_Concentration, Peak_Height, phosphate, po4, preliminary, sample, Sample_ID, science, sea, seawater, sed, Sed_mass, step, time, water";
    String keywords_vocabulary "GCMD Science Keywords";
    String license "https://www.bco-dmo.org/dataset/798995/license";
    String metadata_source "https://www.bco-dmo.org/api/dataset/798995";
    String param_mapping "{'798995': {}}";
    String parameter_source "https://www.bco-dmo.org/mapserver/dataset/798995/parameters";
    String people_0_affiliation "University of California-Santa Cruz";
    String people_0_affiliation_acronym "UC Santa Cruz";
    String people_0_person_name "Adina Paytan";
    String people_0_person_nid "50821";
    String people_0_role "Principal Investigator";
    String people_0_role_type "originator";
    String people_1_affiliation "University of California-Santa Cruz";
    String people_1_affiliation_acronym "UC Santa Cruz";
    String people_1_person_name "Dr Delphine Defforey";
    String people_1_person_nid "664058";
    String people_1_role "Co-Principal Investigator";
    String people_1_role_type "originator";
    String people_2_affiliation "Woods Hole Oceanographic Institution";
    String people_2_affiliation_acronym "WHOI BCO-DMO";
    String people_2_person_name "Amber D. York";
    String people_2_person_nid "643627";
    String people_2_role "BCO-DMO Data Manager";
    String people_2_role_type "related";
    String project "Marine Sediment Analysis 31P NMR";
    String projects_0_acronym "Marine Sediment Analysis 31P NMR";
    String projects_0_description "We developed and tested a new approach to prepare marine sediment samples for solution 31P nuclear magnetic resonance spectroscopy (31P NMR). This approach addresses the effects of sample pretreatment on sedimentary P composition and increases the signal of low abundance P species in 31P NMR spectra by removing up the majority inorganic P  from sediment samples while causing minimal alteration of the chemical structure of organic P compounds. The method was tested on natural marine sediment samples from different localities (Equatorial Pacific, California Margin and Arctic Ocean) with high inorganic P content, and allowed for the detection of low abundance P forms in samples for which only an orthophosphate signal could be resolved with an NaOH-EDTA extraction alone. This new approach will allow the use of 31P NMR on samples for which low organic P concentrations previously hindered the use of this tool, and will help answer longstanding question regarding the fate of organic P in marine sediments. We developed and tested a new approach to prepare marine sediment samples for solution 31P nuclear magnetic resonance spectroscopy (31P NMR). This approach addresses the effects of sample pretreatment on sedimentary P composition and increases the signal of low abundance P species in 31P NMR spectra by removing up the majority inorganic P  from sediment samples while causing minimal alteration of the chemical structure of organic P compounds. The method was tested on natural marine sediment samples from different localities (Equatorial Pacific, California Margin and Arctic Ocean) with high inorganic P content, and allowed for the detection of low abundance P forms in samples for which only an orthophosphate signal could be resolved with an NaOH-EDTA extraction alone. This new approach will allow the use of 31P NMR on samples for which low organic P concentrations previously hindered the use of this tool, and will help answer longstanding question regarding the fate of organic P in marine sediments. 
NSF C-DEBI Award #156246 to Dr. Adina Paytan
NSF C-DEBI Award #157598 to Dr. Delphine Defforey";
    String projects_0_geolocation "Equatorial Pacific, California Margin, Arctic Ocean";
    String projects_0_name "A new marine sediment sample preparation scheme for  solution 31P NMR analysis";
    String projects_0_project_nid "664054";
    String publisher_name "Biological and Chemical Oceanographic Data Management Office (BCO-DMO)";
    String publisher_type "institution";
    String sourceUrl "(local files)";
    String standard_name_vocabulary "CF Standard Name Table v55";
    String subsetVariables "Analyte_Name";
    String summary "Molybdate reactive phosphorus concentrations in nuclear magnetic resonance (NMR) pretreatment extracts from sediment samples collected during cruises in the Arctic Ocean, California Margin, and Equatorial Pacific from 1992-1998.";
    String title "[MRP sediments with pretreatment] - Molybdate reactive phosphorus concentrations in NMR pretreatment extracts from sediment samples collected during cruises in the Arctic Ocean, California Margin, and Equatorial Pacific from 1992-1998 (A new marine sediment sample preparation scheme for  solution 31P NMR analysis)";
    String version "1";
    String xml_source "osprey2erddap.update_xml() v1.5";
  }
}