URL | https://www.bco-dmo.org/dataset/816527 |
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Download URL | https://www.bco-dmo.org/dataset/816527/data/download |
Media Type | text/tab-separated-values |
Created | June 23, 2020 |
Modified | June 30, 2020 |
State | Preliminary and in progress |
Acquisition Description
Location: North Atlantic, western flank of the mid-Atlantic Ridge 22.75589 N 46.08125 W
Methodology:
Prior to the extraction, we freeze-dried, ground and sieved sediment samples to less than 125 μm (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 μm 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 μm 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 μm 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 μm 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 μM PO4) were diluted ten-fold to prevent matrix interference with color development. The detection limit for P on this instrument is 0.2 μM. We derived MUP concentrations by subtracting MRP from total P concentrations, which are included in a different spreadsheet.
Processing Description
Data were processed in Excel.
BCO-DMO Data Manager Processing Notes:
* Data from originally submitted Excel file Data_MRP.xlsx exported as csv. Sheets for step 1 and step 2 combined into one data table. Values exported as formatted in excel with decimals with three decimal places.
* added a conventional header with dataset name, PI name, version date
* modified parameter names to conform with BCO-DMO naming conventions
* blank values in this dataset are displayed as “nd” for “no data.” nd is the default missing data identifier in the BCO-DMO system.
* Date format changed to ISO 8601 format yyyy-mm-dd
Instruments
Parameters
Experimental conditions applied to experimental units. In comparative experiments, members of the complementary group, the control group, receive either no treatment or a standard treatment.
date; generally reported in GMT as YYYYMMDD (year; month; day); also as MMDD (month; day); EqPac dates are local Hawaii time. ISO_Date format is YYYY-MM-DD (http://www.iso.org/iso/home/standards/iso8601.htm)
unique sample identification or number; any combination of alpha numeric characters; precise definition is file dependent
Orthophosphate (phosphate, reactive phosphorus), Various units.
Concentration adjusted after blank
Orthophosphate (phosphate, reactive phosphorus), Various units.
Orthophosphate (phosphate, reactive phosphorus), Various units.
Orthophosphate (phosphate, reactive phosphorus), Various units.
Peak area
Dataset Maintainers
Name | Affiliation | Contact |
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Adina Paytan | University of California-Santa Cruz (UC Santa Cruz) | ✓ |
Delphine Defforey | University of California-Santa Cruz (UC Santa Cruz) | ✓ |
Amber York | University of California-Santa Cruz (UC Santa Cruz) | |
Amber York | University of California-Santa Cruz (UC Santa Cruz) | |
Amber York | Woods Hole Oceanographic Institution (WHOI BCO-DMO) |
BCO-DMO Project Info
Project Title | Potential phosphorus uptake mechanisms of the deep sedimentary biosphere |
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Acronym | Deep sea sediments |
URL | https://www.bco-dmo.org/project/664073 |
Created | November 7, 2016 |
Modified | November 7, 2016 |
Project Description
The goal of this project is to explore potential microbial P uptake mechanisms in marine sediments beneath the North Atlantic Gyre and their effects on the relative distribution of organic P compounds as a function of burial depth and changing redox conditions. We use a combination of metagenomic analyses and solution 31P nuclear magnetic resonance spectroscopy (31P NMR) to investigate (1) the presence of microbial functional genes pertaining to P uptake and metabolism and (2) the possible P substrates for the deep biosphere in these oligotrophic sediments.
NSF C-DEBI Award #156246 to Dr. Adina Paytan
NSF C-DEBI Award #157598 to Dr. Delphine Defforey
Data Project Maintainers
Name | Affiliation | Role |
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Adina Paytan | University of California-Santa Cruz (UC Santa Cruz) | Principal Investigator |
Benjamin J. Tully | Texas A&M University (TAMU) | Co-Principal Investigator |
Jason B. Sylvan | University of Southern California (USC) | Co-Principal Investigator |
Delphine Defforey | University of California-Santa Cruz (UC Santa Cruz) | Co-Principal Investigator |
Barbara J. Cade-Menun | Agriculture and Agri-Food Canada (AGR GC) | Co-Principal Investigator |
Brandi Kiel Reese | Texas A&M, Corpus Christi (TAMU-CC) | Co-Principal Investigator |
Laura A. Zinke | University of Southern California (USC) | Co-Principal Investigator |