http://lod.bco-dmo.org/id/dataset/877681
eng; USA
utf8
dataset
Highest level of data collection, from a common set of sensors or instrumentation, usually within the same research project
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
2022-08-03
ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
ISO 19115-2:2009(E)
Total Zn and Cd uptake rates of natural phytoplankton assemblages measured during the 2017-2018 CICLOPS expedition
2022-08-03
publication
2022-08-03
revision
Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA)
2022-10-05
publication
https://doi.org/10.26008/1912/bco-dmo.877681.1
Mak A. Saito
Woods Hole Oceanographic Institution
principalInvestigator
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
publisher
Cite this dataset as: Kellogg, R., Saito, M. A. (2022) Total Zn and Cd uptake rates of natural phytoplankton assemblages measured during the 2017-2018 CICLOPS expedition. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2022-08-03 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.877681.1 [access date]
Total Zn and Cd uptake rates of natural assemblages measured during the CICLOPS expedition Dataset Description: Methods and Sampling: <p><strong>Methodology:&nbsp;</strong></p>
<p><strong>Sampling and analytical procedures:&nbsp;</strong></p>
<p><br />
<em>Study area and sample collection</em></p>
<p>Sample collection occurred during the CICLOPS (Cobalamin and Iron Co-Limitation of Phytoplankton Species) expedition (expedition code NBP18-01; chief scientist G.R. DiTullio) aboard the RVIB Nathaniel B. Palmer, December 11, 2017 – March 3, 2018 in the Amundsen Sea and Ross Sea of the Southern Ocean. Water samples were collected using trace metal sampling protocols described previously (Noble et al. 2012). A trace metal clean rosette suspended on a Kevlar line and equipped with twelve 8L X-Niskin bottles (Ocean Test Equipment) was used to collect seawater at depths ranging from 10 – 600 m.</p>
<p><em>Preparation of plasticware</em></p>
<p>Polyethylene and polycarbonate sampling and incubation bottles were rigorously cleaned to remove trace metal contaminants before use. Bottles with rinsed with Milli-Q water (Millipore), soaked for 72h in &lt;1% Citranox detergent, rotated, soaked for an additional 72h, and then rinsed five times with Milli-Q water. Bottles were then filled with 10% HCl (Baker instra-analyzed) by volume and soaked for a minimum of one week, rotated, and soaked for another week. Bottles were then rinsed five times with dilute acid (HCl, pH 2) and stored double-bagged in plastic zip bags. All cleaning work was conducted in a Class 100 clean room.</p>
<p><em>Analyses of total dissolved Cd and Zn using isotope dilution</em></p>
<p>Samples for the analysis of total dissolved Zn, Cd, Fe, Mn, Cu and Ni concentrations were collected shipboard by pressure-filtering X-Niskin bottles through an acid-washed 142mm, 0.2µM Supor membrane filter (Pall) within 3 hours of rosette recovery using high purity (99.999%) N<sub>2</sub> gas. Total dissolved water samples were collected into 250mL trace metal clean polyethylene bottles and were stored double-bagged in plastic zip bags. Seawater samples for <sup>110</sup>Cd and <sup>67</sup>Zn stable isotope uptake experiments were collected in the same way but without filtering. All sample collection occurred shipboard within a trace metal clean van containing laminar flow hoods and plastic sheeting. Samples for total dissolved metal analysis were acidified to pH 1.7 with high purity HCl (Optima, Fisher Scientific) within 7 months of sampling and were stored acidified at room temperature for over 1 year prior to analysis.</p>
<p>Quantification of dissolved metals in samples and reference seawater was performed for total dissolved Fe, Ni, Cu, Zn, and Cd using isotope dilution. 15mL of acidified seawater sample was spiked with 50μL of a stable isotope spike solution artificially enriched in <sup>57</sup>Fe, <sup>61</sup>Ni, <sup>65</sup>Cu, <sup>67</sup>Zn, and <sup>110</sup>Cd. All stable isotopes were received in solid form (Oak Ridge National Laboratory). Initial dissolution and all subsequent dilutions were made using concentrated nitric acid (Optima, Fisher Scientific). Concentrations and spike ratios were verified by ICP-MS using a multi-element standard curve (SPEX CertiPrep). The composition of the isotope spike was made such that the 15mL spiked sample contained the following ratios: <sup>57</sup>Fe/<sup>56</sup>Fe = 0.7, <sup>61</sup>Ni/<sup>60</sup>Ni = 0.5, <sup>65</sup>Cu/<sup>63</sup>Cu = 1, <sup>67</sup>Zn/<sup>66</sup>Zn = 0.7, and <sup>110</sup>Cd/<sup>114</sup>Cd = 1 and were verified with ICP-MS. These ratios were chosen to minimize the uncertainty introduced by error propagation through the isotope dilution equation (Wu and Boyle 1998; Rudge et al. 2009; Tan et al. 2020). Because it is monoisotopic, total dissolved Mn was calculated using a modified isotope dilution equation. This equation and its&nbsp;details are captured in the Supplemental Files dropdown on this metadata landing page, within the file titled,&nbsp;<em>Modified Isotope Dilution Equation.&nbsp;</em></p>
<p>Preconcentration of spiked seawater samples for total dissolved metal analysis was performed using the automated solid phase extraction system seaFAST-pico (Elemental Scientific) in offline concentration mode with an initial volume of 15mL and elution volume of 500µL (Bown et al. 2017; Rapp et al. 2017; Jackson et al. 2018; Wuttig et al. 2019). The seaFAST contains a Nobias-chelate PA1 resin column (ethylenediaminetriacete and iminodiacetate) suitable for the simultaneous preconcentration of several trace metals (Fe, Mn, Zn, Cu, Co, Cd, Ni) with high sensitivity and quantitative recovery (Sohrin et al. 2008; Biller and Bruland 2012). Adjusted seaFAST software settings were a 17 second load loop time and a single 10mL load cycle. Process blanks consisted of pH 2 HCl (Optima, Fisher Scientific) and were processed as samples were to account for any contamination introduced by instrument processing.</p>
<p>Reagents consisted of a 1.5M ammonium acetate pH 6.0 buffer made using glacial acetic acid and ammonium hydroxide (20-22%) of the highest purity (Optima, Fisher Chemical), a 1% nitric acid rinse solution (Optima grade, Fisher Chemical), and a 10% nitric acid elution buffer (Optima grade, Fisher Chemical) with 10 ppb indium (<sup>115</sup>In, SPEX CertiPrep) added as an internal standard. Solutions were prepared with 18.2 Ω Milli-Q water (Millipore). Polypropylene 15mL centrifuge tubes used in sample processing were made trace metal clean by soaking in 10% HCl for 5 days and rinsing with pH 2 HCl prior to use.</p>
<p>Following offline seaFAST preconcentration, multielemental quantitative analysis was performed using an iCAP-Q inductively coupled plasma-mass spectrometer (ICP-MS) (Thermo Scientific). Oxide interference on metal isotopes was minimized through the use of a cooled spray chamber and helium collision gas. Analytes were measured in single quadruple mode (kinetic energy discrimination [KED]). Concentrations of Mn, Fe, Ni, Cu, Zn and Cd were determined using a six-point external standard curve of a multi-element standard (SPEX CertiPrep), diluted to range from 1-10 ppb in 5% nitric acid. An indium standard (SPEX CertiPrep) was similarly added to these standard stocks, diluted to range 1-10 ppb. Instrument injection blanks consisted of 5% nitric acid in Milli-Q. Standard curve R<sup>2</sup> values were ≥0.98 for all metals monitored. Method accuracy and precision were assessed using the 2009 GEOTRACES coastal surface seawater (GSC) standard which produced values consistent with consensus results.</p>
<p>&nbsp;</p>
<p><em>Uptake experiments: <sup>67</sup>Zn and <sup>110</sup>Cd spiking, incubation, and sample collection</em></p>
<p><sup>67</sup>Zn and <sup>110</sup>Cd and stable isotope uptake experiments were modelled after those conducted by Cox et. al. 2014. Raw (unfiltered) seawater was collected shipboard over a depth range of 10 – 600m at each station into 250mL trace metal clean polycarbonate incubation bottles. All incubation bottles were filled with minimal headspace such that the total culture volume was ~275mL. Two incubation bottles per depth were filled with raw seawater— one was spiked with <sup>67</sup>Zn, the other was spiked with <sup>110</sup>Cd. The Cd and Zn isotope spikes were prepared by dissolving <sup>110</sup>CdO and <sup>67</sup>ZnO (Oak Ridge National Laboratory) in 5% HNO<sub>3</sub> (Seastar Baseline) and were diluted using Milli-Q water to minimize added acidity. When added to the filled incubation bottles, the total added (spiked) concentration of Cd was 300 pM and the total added concentration of Zn was 2 nM. The chosen total added concentrations were based on the surface ratio of total dissolved Cd (dCd) to total dissolved Zn (dZn) reported previously for the Ross Sea (Fitzwater et al. 2000). Immediately after spiking, incubation bottles were sealed, inverted to mix, and transferred to flow-through on-deck incubators for 24hr. Incubators were shielded by black net neutral density screening to allow 20% ambient light penetration.</p>
<p>Biomass was collected after 24hr by vacuum filtering the entire volume of each incubation sample at 34.5 kPa (5 psi) onto an acid-cleaned 3mm, 50mm Versapore filter (Pall) mounted on an acid-cleaned Teflon (Savillex) filtration rig. Samples were 3mm filtered rather than 0.2mm in order to minimize filtration time (and thus time exposed to potential contamination) and to capture the bulk of eukaryotic phytoplankton biomass typically found in the Southern Ocean. ~1 mL of 0.2mm filtered surface (10m depth) seawater was used to rinse the sample before collecting the filter into an acid-cleaned 2mL cryovial using acid-rinsed plastic forceps. Filter blanks were duplicate 3mm acid-clean Versapore filters that were placed onto the filtration rig, rinsed with filtered surface seawater, collected, stored, and processed as samples were in order to correct for any contaminating metals present on the filters themselves. Blanks were collected at each station. Filters were stored frozen at -80⁰C in acid-cleaned cryovials until analysis. The filtration rig was rinsed with pH 2 HCl between samples. Polycarbonate incubation bottles were cleaned between stations with a 10% HCl rinse and several rinses in Milli-Q water, followed by a brief soak in 10% HCl followed by a pH 2 HCl rinse. All spike addition and sample filtration procedures were completed in a fabricated shipboard positive-pressure clean room environment made of laminar flow hoods and plastic sheeting.</p>
<p><em>Filter digestion and particulate ICP-MS analysis</em></p>
<p>All work was performed in a Class 100 clean room under laminar flow hoods. Sample filters were retrieved from storage at -80⁰C, removed from cryovials using plastic acid-washed forceps, and transferred into trace metal clean 15 mL PFA vials with 4 mL of 5% HNO<sub>3</sub> (Optima) containing a 1 ppb Indium (In) internal standard. Filters were digested for ~3.5h at 140⁰C using a HotBlock® heating block (Environmental Express, USA) before the filters were removed and discarded, leaving behind the liquid extract. After evaporating the remaining solution to just dryness, the residue was resuspended in 2 mL of 5% HNO<sub>3 </sub>(Optima) by light vortexing. Process blank filters were digested and processed as sample filters were. Digests were analyzed in duplicate by ICP-MS using a Thermo ICAP-Q plasma mass spectrometer calibrated to a multi-element standard curve (Spex Certiprep) over a range of 1 – 20 ppb. Natural Cd and Zn isotope abundances of the standards were assumed to calculate concentrations of <sup>110</sup>Cd, <sup>111</sup>Cd, <sup>114</sup>Cd, <sup>67</sup>Zn, <sup>66</sup>Zn, and <sup>68</sup>Zn. Digests were analyzed in KED mode after an 85s sample uptake window and element mass windows were scanned 3 times during measurements. The 1 ppb In internal standard was used to correct for variation in sample delivery and plasma suppression between samples. Process blanks were subtracted from measured sample concentrations. Phosphorus concentrations were simultaneously measured by ICP-MS and were calibrated to a standard curve ranging from 100 – 3,200 ppb using a 1 ppm certified P stock (Alfa Aesar Specpure). The equation and its details used for the calculations described above are captured in the Supplemental Files section of this metadata landing page within the file titled,&nbsp;<em>Particulate Rates Metal Concentration Equation.</em></p>
<p>The Zn spike and Cd spike were also analyzed by ICP-MS using a 1:9 dilution of spike solution into 5% HNO<sub>3</sub> 1 ppb In to determine isotopic compositions and concentrations. When added to filled incubation bottles (275mL total volume), the added concentrations were 288 pM 110Cd, 4.51 pM 111Cd, and 1.69 pM 114Cd for Cd spiked bottles, and were 1.91 nM 67Zn,&nbsp;0.045&nbsp;nM 66Zn, and 0.047 nM 68Zn for Zn spiked bottles.</p>
<p>&nbsp;</p>
<p><em>Calculating zinc and cadmium uptake using <sup>67</sup>Zn and <sup>110</sup>Cd</em></p>
<p>Total Zn and Cd uptake was calculated using Eq. (3) and Eq. (4), respectively. These equations can be found under the Supplemental Files section of this metadata landing page, within the file titled,&nbsp;<em>Metal Uptake Rate Equations.&nbsp;</em><sup>110</sup>Cd<sub>Sample</sub> and <sup>67</sup>Zn<sub>Sample </sub>are the particulate <sup>110</sup>Cd and <sup>67</sup>Zn measured by ICP-MS analysis of the 3μm sample filter, normalized to the total culture volume (275 mL) and 24hr of incubation. <sup>110</sup>Cd<sub>Sample</sub> and <sup>67</sup>Zn<sub>Sample</sub> already in the particulate fraction (that is, the pCd and pZn that existed in the water column upon collection of the raw seawater samples) was accounted for by subtracting the particulate blank, <sup>110</sup>Cd<sub>Blank</sub> and <sup>67</sup>Zn<sub>Blank.&nbsp; </sub><sup>110</sup>Cd<sub>Blank</sub> and <sup>67</sup>Zn<sub>Blank </sub>will hereafter be referred to as “pre-existing particulate <sup>110</sup>Cd and <sup>67</sup>Zn”. The pre-existing particulate blank value for <sup>110</sup>Cd was obtained from incubation bottles that had Zn added, but no Cd spike. Likewise, the pre-existing particulate blank value for <sup>67</sup>Zn was obtained from incubation bottles that had Cd added, but no Zn spike. The <sup>67</sup>Zn spike solution was confirmed to contain virtually no <sup>110</sup>Cd, <sup>111</sup>Cd, <sup>114</sup>Cd. The <sup>110</sup>Cd spike was likewise confirmed to contain virtually no <sup>67</sup>Zn, <sup>64</sup>Zn, <sup>66</sup>Zn. As a result, we assumed that the added <sup>67</sup>Zn spike did not affect the pre-existing Cd, nor did the <sup>110</sup>Cd spike affect the pre-existing Zn. It is assumed that the pre-existing particulate blank was in steady state, i.e. that it represented the Cd or Zn already in the particulate fraction and any possible natural uptake that could occur during incubation for 24h was negligible. The total dissolved pool of each metal isotope (denominator of each equation) is the sum of the dissolved <sup>110</sup>Cd or <sup>67</sup>Zn added as the spike (<sup>110</sup>Cd<sub>Spike</sub>, <sup>67</sup>Zn<sub>Spike</sub>) plus the natural, pre-existing dissolved <sup>110</sup>Cd or <sup>67</sup>Zn that was in the raw seawater (<sup>110</sup>Cd<sub>Natural</sub>, <sup>67</sup>Zn<sub>Natural</sub>) collected at each depth. To calculate <sup>110</sup>Cd<sub>Natural</sub> and <sup>67</sup>Zn<sub>Natural</sub>, the total dissolved Cd or Zn measured by isotope dilution-ICP-MS (Cd<sub>Total</sub>, Zn<sub>Total</sub>) was multiplied by the natural abundance of <sup>110</sup>Cd and <sup>67</sup>Zn (12.49% and 4.10%, respectively). Dividing the particulate <sup>110</sup>Cd and <sup>67</sup>Zn by the total dissolved <sup>110</sup>Cd and <sup>67</sup>Zn yields the fraction of these metal isotopes that moved from the dissolved pool to the particulate pool per day.&nbsp;</p>
<p>&nbsp;</p>
Funding provided by NSF Office of Polar Programs (formerly NSF PLR) (NSF OPP) Award Number: OPP-1644073 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1644073
Funding provided by NSF Office of Polar Programs (formerly NSF PLR) (NSF OPP) Award Number: OPP-1643684 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1643684
Funding provided by NSF Office of Polar Programs (formerly NSF PLR) (NSF OPP) Award Number: OPP-1643845 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1643845
completed
Mak A. Saito
Woods Hole Oceanographic Institution
508-289-2393
266 Woods Hole Rd. MS #51 Watson Lab
Woods Hole
MA
02543
USA
msaito@whoi.edu
pointOfContact
asNeeded
Dataset Version: 1
Unknown
Station
Lat_deg_N
Lon_deg_E
Collection_datetime
Depth_m
Bottle
Zn_UR_pmolLd
Cd_UR_pmolLd
iCAP-Q inductively coupled plasma-mass spectrometer (ICP-MS) (Thermo Scientific)
Twelve 8L X-Niskin bottles (Ocean Test Equipment)
Automated solid phase extraction system seaFAST-pico (Elemental Scientific)
theme
None, User defined
station
latitude
longitude
date
depth
bottle
trace metal concentration
featureType
BCO-DMO Standard Parameters
Inductively Coupled Plasma Mass Spectrometer
Niskin bottle
SeaFAST Automated Preconcentration System
instrument
BCO-DMO Standard Instruments
NBP1801
service
Deployment Activity
Western Ross Sea, Southern Ocean
place
Locations
otherRestrictions
otherRestrictions
Access Constraints: none. Use Constraints: Please follow guidelines at: http://www.bco-dmo.org/terms-use Distribution liability: Under no circumstances shall BCO-DMO be liable for any direct, incidental, special, consequential, indirect, or punitive damages that result from the use of, or the inability to use, the materials in this data submission. If you are dissatisfied with any materials in this data submission your sole and exclusive remedy is to discontinue use.
Collaborative Research: Cobalamin and Iron Co-Limitation Of Phytoplankton Species in Terra Nova Bay
https://osprey.bco-dmo.org/project/774945
Collaborative Research: Cobalamin and Iron Co-Limitation Of Phytoplankton Species in Terra Nova Bay
<p>NSF abstract:<br />
Phytoplankton blooms in the coastal waters of the Ross Sea, Antarctica are typically dominated by either diatoms or Phaeocystis Antarctica (a flagellated algae that often can form large colonies in a gelatinous matrix). The project seeks to determine if an association of bacterial populations with Phaeocystis antarctica colonies can directly supply Phaeocystis with Vitamin B12, which can be an important co-limiting micronutrient in the Ross Sea. The supply of an essential vitamin coupled with the ability to grow at lower iron concentrations may put Phaeocystis at a competitive advantage over diatoms. Because Phaeocystis cells can fix more carbon than diatoms and Phaeocystis are not grazed as efficiently as diatoms, the project will help in refining understanding of carbon dynamics in the region as well as the basis of the food web webs. Such understanding also has the potential to help refine predictive ecological models for the region. The project will conduct public outreach activities and will contribute to undergraduate and graduate research. Engagement of underrepresented students will occur during summer student internships. A collaboration with Italian Antarctic researchers, who have been studying the Terra Nova Bay ecosystem since the 1980s, aims to enhance the project and promote international scientific collaborations.</p>
<p>The study will test whether a mutualistic symbioses between attached bacteria and Phaeocystis provides colonial cells a mechanism for alleviating chronic Vitamin B12 co-limitation effects thereby conferring them with a competitive advantage over diatom communities. The use of drifters in a time series study will provide the opportunity to track in both space and time a developing algal bloom in Terra Nova Bay and to determine community structure and the physiological nutrient status of microbial populations. A combination of flow cytometry, proteomics, metatranscriptomics, radioisotopic and stable isotopic labeling experiments will determine carbon and nutrient uptake rates and the role of bacteria in mitigating potential vitamin B12 and iron limitation. Membrane inlet and proton transfer reaction mass spectrometry will also be used to estimate net community production and release of volatile organic carbon compounds that are climatically active. Understanding how environmental parameters can influence microbial community dynamics in Antarctic coastal waters will advance an understanding of how changes in ocean stratification and chemistry could impact the biogeochemistry and food web dynamics of Southern Ocean ecosystems.</p>
CICLOPS
largerWorkCitation
project
eng; USA
oceans
Western Ross Sea, Southern Ocean
160
-115
-80
-70
2017-12-30
2018-02-18
Amundsen Sea, Ross Sea, Terra Nova Bay
0
BCO-DMO catalogue of parameters from Total Zn and Cd uptake rates of natural phytoplankton assemblages measured during the 2017-2018 CICLOPS expedition
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
http://lod.bco-dmo.org/id/dataset-parameter/878039.rdf
Name: Station
Units: unitless
Description: <p>Station number</p>
http://lod.bco-dmo.org/id/dataset-parameter/878040.rdf
Name: Lat_deg_N
Units: unitless
Description: <p>Latitude in decimal degrees; positive values indicate North</p>
http://lod.bco-dmo.org/id/dataset-parameter/878041.rdf
Name: Lon_deg_E
Units: unitless
Description: <p>Longitude in decimal degrees; negative values indicate West</p>
http://lod.bco-dmo.org/id/dataset-parameter/878042.rdf
Name: Collection_datetime
Units: unitless
Description: <p>Time of sampling; %Y-%M-%D %H:%M</p>
http://lod.bco-dmo.org/id/dataset-parameter/878043.rdf
Name: Depth_m
Units: Meters (m)
Description: <p>Depth of sampling</p>
http://lod.bco-dmo.org/id/dataset-parameter/878044.rdf
Name: Bottle
Units: unitless
Description: <p>Bottle ID</p>
http://lod.bco-dmo.org/id/dataset-parameter/878045.rdf
Name: Zn_UR_pmolLd
Units: picomoles per liter per day (pmol/L/d)
Description: <p>Total zinc uptake rate</p>
http://lod.bco-dmo.org/id/dataset-parameter/878046.rdf
Name: Cd_UR_pmolLd
Units: picomoles per liter per day (pmol/L/d)
Description: <p>Total cadmium uptake rate</p>
GB/NERC/BODC > British Oceanographic Data Centre, Natural Environment Research Council, United Kingdom
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
17245
https://darchive.mblwhoilibrary.org/bitstream/1912/29391/1/dataset-877681_ciclops-total-zn-and-cd-uptake-rates__v1.tsv
download
https://doi.org/10.26008/1912/bco-dmo.877681.1
download
onLine
dataset
<p><strong>Methodology:&nbsp;</strong></p>
<p><strong>Sampling and analytical procedures:&nbsp;</strong></p>
<p><br />
<em>Study area and sample collection</em></p>
<p>Sample collection occurred during the CICLOPS (Cobalamin and Iron Co-Limitation of Phytoplankton Species) expedition (expedition code NBP18-01; chief scientist G.R. DiTullio) aboard the RVIB Nathaniel B. Palmer, December 11, 2017 – March 3, 2018 in the Amundsen Sea and Ross Sea of the Southern Ocean. Water samples were collected using trace metal sampling protocols described previously (Noble et al. 2012). A trace metal clean rosette suspended on a Kevlar line and equipped with twelve 8L X-Niskin bottles (Ocean Test Equipment) was used to collect seawater at depths ranging from 10 – 600 m.</p>
<p><em>Preparation of plasticware</em></p>
<p>Polyethylene and polycarbonate sampling and incubation bottles were rigorously cleaned to remove trace metal contaminants before use. Bottles with rinsed with Milli-Q water (Millipore), soaked for 72h in &lt;1% Citranox detergent, rotated, soaked for an additional 72h, and then rinsed five times with Milli-Q water. Bottles were then filled with 10% HCl (Baker instra-analyzed) by volume and soaked for a minimum of one week, rotated, and soaked for another week. Bottles were then rinsed five times with dilute acid (HCl, pH 2) and stored double-bagged in plastic zip bags. All cleaning work was conducted in a Class 100 clean room.</p>
<p><em>Analyses of total dissolved Cd and Zn using isotope dilution</em></p>
<p>Samples for the analysis of total dissolved Zn, Cd, Fe, Mn, Cu and Ni concentrations were collected shipboard by pressure-filtering X-Niskin bottles through an acid-washed 142mm, 0.2µM Supor membrane filter (Pall) within 3 hours of rosette recovery using high purity (99.999%) N<sub>2</sub> gas. Total dissolved water samples were collected into 250mL trace metal clean polyethylene bottles and were stored double-bagged in plastic zip bags. Seawater samples for <sup>110</sup>Cd and <sup>67</sup>Zn stable isotope uptake experiments were collected in the same way but without filtering. All sample collection occurred shipboard within a trace metal clean van containing laminar flow hoods and plastic sheeting. Samples for total dissolved metal analysis were acidified to pH 1.7 with high purity HCl (Optima, Fisher Scientific) within 7 months of sampling and were stored acidified at room temperature for over 1 year prior to analysis.</p>
<p>Quantification of dissolved metals in samples and reference seawater was performed for total dissolved Fe, Ni, Cu, Zn, and Cd using isotope dilution. 15mL of acidified seawater sample was spiked with 50μL of a stable isotope spike solution artificially enriched in <sup>57</sup>Fe, <sup>61</sup>Ni, <sup>65</sup>Cu, <sup>67</sup>Zn, and <sup>110</sup>Cd. All stable isotopes were received in solid form (Oak Ridge National Laboratory). Initial dissolution and all subsequent dilutions were made using concentrated nitric acid (Optima, Fisher Scientific). Concentrations and spike ratios were verified by ICP-MS using a multi-element standard curve (SPEX CertiPrep). The composition of the isotope spike was made such that the 15mL spiked sample contained the following ratios: <sup>57</sup>Fe/<sup>56</sup>Fe = 0.7, <sup>61</sup>Ni/<sup>60</sup>Ni = 0.5, <sup>65</sup>Cu/<sup>63</sup>Cu = 1, <sup>67</sup>Zn/<sup>66</sup>Zn = 0.7, and <sup>110</sup>Cd/<sup>114</sup>Cd = 1 and were verified with ICP-MS. These ratios were chosen to minimize the uncertainty introduced by error propagation through the isotope dilution equation (Wu and Boyle 1998; Rudge et al. 2009; Tan et al. 2020). Because it is monoisotopic, total dissolved Mn was calculated using a modified isotope dilution equation. This equation and its&nbsp;details are captured in the Supplemental Files dropdown on this metadata landing page, within the file titled,&nbsp;<em>Modified Isotope Dilution Equation.&nbsp;</em></p>
<p>Preconcentration of spiked seawater samples for total dissolved metal analysis was performed using the automated solid phase extraction system seaFAST-pico (Elemental Scientific) in offline concentration mode with an initial volume of 15mL and elution volume of 500µL (Bown et al. 2017; Rapp et al. 2017; Jackson et al. 2018; Wuttig et al. 2019). The seaFAST contains a Nobias-chelate PA1 resin column (ethylenediaminetriacete and iminodiacetate) suitable for the simultaneous preconcentration of several trace metals (Fe, Mn, Zn, Cu, Co, Cd, Ni) with high sensitivity and quantitative recovery (Sohrin et al. 2008; Biller and Bruland 2012). Adjusted seaFAST software settings were a 17 second load loop time and a single 10mL load cycle. Process blanks consisted of pH 2 HCl (Optima, Fisher Scientific) and were processed as samples were to account for any contamination introduced by instrument processing.</p>
<p>Reagents consisted of a 1.5M ammonium acetate pH 6.0 buffer made using glacial acetic acid and ammonium hydroxide (20-22%) of the highest purity (Optima, Fisher Chemical), a 1% nitric acid rinse solution (Optima grade, Fisher Chemical), and a 10% nitric acid elution buffer (Optima grade, Fisher Chemical) with 10 ppb indium (<sup>115</sup>In, SPEX CertiPrep) added as an internal standard. Solutions were prepared with 18.2 Ω Milli-Q water (Millipore). Polypropylene 15mL centrifuge tubes used in sample processing were made trace metal clean by soaking in 10% HCl for 5 days and rinsing with pH 2 HCl prior to use.</p>
<p>Following offline seaFAST preconcentration, multielemental quantitative analysis was performed using an iCAP-Q inductively coupled plasma-mass spectrometer (ICP-MS) (Thermo Scientific). Oxide interference on metal isotopes was minimized through the use of a cooled spray chamber and helium collision gas. Analytes were measured in single quadruple mode (kinetic energy discrimination [KED]). Concentrations of Mn, Fe, Ni, Cu, Zn and Cd were determined using a six-point external standard curve of a multi-element standard (SPEX CertiPrep), diluted to range from 1-10 ppb in 5% nitric acid. An indium standard (SPEX CertiPrep) was similarly added to these standard stocks, diluted to range 1-10 ppb. Instrument injection blanks consisted of 5% nitric acid in Milli-Q. Standard curve R<sup>2</sup> values were ≥0.98 for all metals monitored. Method accuracy and precision were assessed using the 2009 GEOTRACES coastal surface seawater (GSC) standard which produced values consistent with consensus results.</p>
<p>&nbsp;</p>
<p><em>Uptake experiments: <sup>67</sup>Zn and <sup>110</sup>Cd spiking, incubation, and sample collection</em></p>
<p><sup>67</sup>Zn and <sup>110</sup>Cd and stable isotope uptake experiments were modelled after those conducted by Cox et. al. 2014. Raw (unfiltered) seawater was collected shipboard over a depth range of 10 – 600m at each station into 250mL trace metal clean polycarbonate incubation bottles. All incubation bottles were filled with minimal headspace such that the total culture volume was ~275mL. Two incubation bottles per depth were filled with raw seawater— one was spiked with <sup>67</sup>Zn, the other was spiked with <sup>110</sup>Cd. The Cd and Zn isotope spikes were prepared by dissolving <sup>110</sup>CdO and <sup>67</sup>ZnO (Oak Ridge National Laboratory) in 5% HNO<sub>3</sub> (Seastar Baseline) and were diluted using Milli-Q water to minimize added acidity. When added to the filled incubation bottles, the total added (spiked) concentration of Cd was 300 pM and the total added concentration of Zn was 2 nM. The chosen total added concentrations were based on the surface ratio of total dissolved Cd (dCd) to total dissolved Zn (dZn) reported previously for the Ross Sea (Fitzwater et al. 2000). Immediately after spiking, incubation bottles were sealed, inverted to mix, and transferred to flow-through on-deck incubators for 24hr. Incubators were shielded by black net neutral density screening to allow 20% ambient light penetration.</p>
<p>Biomass was collected after 24hr by vacuum filtering the entire volume of each incubation sample at 34.5 kPa (5 psi) onto an acid-cleaned 3mm, 50mm Versapore filter (Pall) mounted on an acid-cleaned Teflon (Savillex) filtration rig. Samples were 3mm filtered rather than 0.2mm in order to minimize filtration time (and thus time exposed to potential contamination) and to capture the bulk of eukaryotic phytoplankton biomass typically found in the Southern Ocean. ~1 mL of 0.2mm filtered surface (10m depth) seawater was used to rinse the sample before collecting the filter into an acid-cleaned 2mL cryovial using acid-rinsed plastic forceps. Filter blanks were duplicate 3mm acid-clean Versapore filters that were placed onto the filtration rig, rinsed with filtered surface seawater, collected, stored, and processed as samples were in order to correct for any contaminating metals present on the filters themselves. Blanks were collected at each station. Filters were stored frozen at -80⁰C in acid-cleaned cryovials until analysis. The filtration rig was rinsed with pH 2 HCl between samples. Polycarbonate incubation bottles were cleaned between stations with a 10% HCl rinse and several rinses in Milli-Q water, followed by a brief soak in 10% HCl followed by a pH 2 HCl rinse. All spike addition and sample filtration procedures were completed in a fabricated shipboard positive-pressure clean room environment made of laminar flow hoods and plastic sheeting.</p>
<p><em>Filter digestion and particulate ICP-MS analysis</em></p>
<p>All work was performed in a Class 100 clean room under laminar flow hoods. Sample filters were retrieved from storage at -80⁰C, removed from cryovials using plastic acid-washed forceps, and transferred into trace metal clean 15 mL PFA vials with 4 mL of 5% HNO<sub>3</sub> (Optima) containing a 1 ppb Indium (In) internal standard. Filters were digested for ~3.5h at 140⁰C using a HotBlock® heating block (Environmental Express, USA) before the filters were removed and discarded, leaving behind the liquid extract. After evaporating the remaining solution to just dryness, the residue was resuspended in 2 mL of 5% HNO<sub>3 </sub>(Optima) by light vortexing. Process blank filters were digested and processed as sample filters were. Digests were analyzed in duplicate by ICP-MS using a Thermo ICAP-Q plasma mass spectrometer calibrated to a multi-element standard curve (Spex Certiprep) over a range of 1 – 20 ppb. Natural Cd and Zn isotope abundances of the standards were assumed to calculate concentrations of <sup>110</sup>Cd, <sup>111</sup>Cd, <sup>114</sup>Cd, <sup>67</sup>Zn, <sup>66</sup>Zn, and <sup>68</sup>Zn. Digests were analyzed in KED mode after an 85s sample uptake window and element mass windows were scanned 3 times during measurements. The 1 ppb In internal standard was used to correct for variation in sample delivery and plasma suppression between samples. Process blanks were subtracted from measured sample concentrations. Phosphorus concentrations were simultaneously measured by ICP-MS and were calibrated to a standard curve ranging from 100 – 3,200 ppb using a 1 ppm certified P stock (Alfa Aesar Specpure). The equation and its details used for the calculations described above are captured in the Supplemental Files section of this metadata landing page within the file titled,&nbsp;<em>Particulate Rates Metal Concentration Equation.</em></p>
<p>The Zn spike and Cd spike were also analyzed by ICP-MS using a 1:9 dilution of spike solution into 5% HNO<sub>3</sub> 1 ppb In to determine isotopic compositions and concentrations. When added to filled incubation bottles (275mL total volume), the added concentrations were 288 pM 110Cd, 4.51 pM 111Cd, and 1.69 pM 114Cd for Cd spiked bottles, and were 1.91 nM 67Zn,&nbsp;0.045&nbsp;nM 66Zn, and 0.047 nM 68Zn for Zn spiked bottles.</p>
<p>&nbsp;</p>
<p><em>Calculating zinc and cadmium uptake using <sup>67</sup>Zn and <sup>110</sup>Cd</em></p>
<p>Total Zn and Cd uptake was calculated using Eq. (3) and Eq. (4), respectively. These equations can be found under the Supplemental Files section of this metadata landing page, within the file titled,&nbsp;<em>Metal Uptake Rate Equations.&nbsp;</em><sup>110</sup>Cd<sub>Sample</sub> and <sup>67</sup>Zn<sub>Sample </sub>are the particulate <sup>110</sup>Cd and <sup>67</sup>Zn measured by ICP-MS analysis of the 3μm sample filter, normalized to the total culture volume (275 mL) and 24hr of incubation. <sup>110</sup>Cd<sub>Sample</sub> and <sup>67</sup>Zn<sub>Sample</sub> already in the particulate fraction (that is, the pCd and pZn that existed in the water column upon collection of the raw seawater samples) was accounted for by subtracting the particulate blank, <sup>110</sup>Cd<sub>Blank</sub> and <sup>67</sup>Zn<sub>Blank.&nbsp; </sub><sup>110</sup>Cd<sub>Blank</sub> and <sup>67</sup>Zn<sub>Blank </sub>will hereafter be referred to as “pre-existing particulate <sup>110</sup>Cd and <sup>67</sup>Zn”. The pre-existing particulate blank value for <sup>110</sup>Cd was obtained from incubation bottles that had Zn added, but no Cd spike. Likewise, the pre-existing particulate blank value for <sup>67</sup>Zn was obtained from incubation bottles that had Cd added, but no Zn spike. The <sup>67</sup>Zn spike solution was confirmed to contain virtually no <sup>110</sup>Cd, <sup>111</sup>Cd, <sup>114</sup>Cd. The <sup>110</sup>Cd spike was likewise confirmed to contain virtually no <sup>67</sup>Zn, <sup>64</sup>Zn, <sup>66</sup>Zn. As a result, we assumed that the added <sup>67</sup>Zn spike did not affect the pre-existing Cd, nor did the <sup>110</sup>Cd spike affect the pre-existing Zn. It is assumed that the pre-existing particulate blank was in steady state, i.e. that it represented the Cd or Zn already in the particulate fraction and any possible natural uptake that could occur during incubation for 24h was negligible. The total dissolved pool of each metal isotope (denominator of each equation) is the sum of the dissolved <sup>110</sup>Cd or <sup>67</sup>Zn added as the spike (<sup>110</sup>Cd<sub>Spike</sub>, <sup>67</sup>Zn<sub>Spike</sub>) plus the natural, pre-existing dissolved <sup>110</sup>Cd or <sup>67</sup>Zn that was in the raw seawater (<sup>110</sup>Cd<sub>Natural</sub>, <sup>67</sup>Zn<sub>Natural</sub>) collected at each depth. To calculate <sup>110</sup>Cd<sub>Natural</sub> and <sup>67</sup>Zn<sub>Natural</sub>, the total dissolved Cd or Zn measured by isotope dilution-ICP-MS (Cd<sub>Total</sub>, Zn<sub>Total</sub>) was multiplied by the natural abundance of <sup>110</sup>Cd and <sup>67</sup>Zn (12.49% and 4.10%, respectively). Dividing the particulate <sup>110</sup>Cd and <sup>67</sup>Zn by the total dissolved <sup>110</sup>Cd and <sup>67</sup>Zn yields the fraction of these metal isotopes that moved from the dissolved pool to the particulate pool per day.&nbsp;</p>
<p>&nbsp;</p>
Specified by the Principal Investigator(s)
<p><strong>Data Processing Notes from Researcher:&nbsp;</strong></p>
<p>For analysis of dissolved metal data, method accuracy and precision were assessed using the 2009 GEOTRACES coastal surface seawater (GSC) standard which produced values consistent with consensus results.</p>
<p><strong>BCO-DMO Processing Notes:&nbsp;</strong></p>
<ul>
<li>Renamed column titled yyyy-mm-dd hh:mm to Collection_date</li>
<li>Rounded latitude and longitude&nbsp;fields to 6 positions after the decimal point&nbsp;&nbsp;</li>
<li>Detailed equations are captured within the Supplemental Files section of this metadata landing page</li>
</ul>
<p>&nbsp;</p>
Specified by the Principal Investigator(s)
asNeeded
7.x-1.1
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
iCAP-Q inductively coupled plasma-mass spectrometer (ICP-MS) (Thermo Scientific)
iCAP-Q inductively coupled plasma-mass spectrometer (ICP-MS) (Thermo Scientific)
PI Supplied Instrument Name: iCAP-Q inductively coupled plasma-mass spectrometer (ICP-MS) (Thermo Scientific) PI Supplied Instrument Description:Following offline seaFAST preconcentration, multielemental quantitative analysis was performed using an iCAP-Q inductively coupled plasma-mass spectrometer (ICP-MS) (Thermo Scientific). Instrument Name: Inductively Coupled Plasma Mass Spectrometer Instrument Short Name:ICP Mass Spec Instrument Description: An ICP Mass Spec is an instrument that passes nebulized samples into an inductively-coupled gas plasma (8-10000 K) where they are atomized and ionized. Ions of specific mass-to-charge ratios are quantified in a quadrupole mass spectrometer. Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/LAB15/
Twelve 8L X-Niskin bottles (Ocean Test Equipment)
Twelve 8L X-Niskin bottles (Ocean Test Equipment)
PI Supplied Instrument Name: Twelve 8L X-Niskin bottles (Ocean Test Equipment) PI Supplied Instrument Description:Water samples were collected using trace metal sampling protocols described previously (Noble et al. 2012). A trace metal clean rosette suspended on a Kevlar line and equipped with twelve 8L X-Niskin bottles (Ocean Test Equipment) was used to collect seawater at depths ranging from 10 – 600 m. Instrument Name: Niskin bottle Instrument Short Name:Niskin bottle Instrument Description: A Niskin bottle (a next generation water sampler based on the Nansen bottle) is a cylindrical, non-metallic water collection device with stoppers at both ends. The bottles can be attached individually on a hydrowire or deployed in 12, 24, or 36 bottle Rosette systems mounted on a frame and combined with a CTD. Niskin bottles are used to collect discrete water samples for a range of measurements including pigments, nutrients, plankton, etc. Community Standard Description: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0412/
Automated solid phase extraction system seaFAST-pico (Elemental Scientific)
Automated solid phase extraction system seaFAST-pico (Elemental Scientific)
PI Supplied Instrument Name: Automated solid phase extraction system seaFAST-pico (Elemental Scientific) PI Supplied Instrument Description:Preconcentration of spiked seawater samples for total dissolved metal analysis was performed using the automated solid phase extraction system seaFAST-pico (Elemental Scientific) in offline concentration mode with an initial volume of 15mL and elution volume of 500µL (Bown et al. 2017; Rapp et al. 2017; Jackson et al. 2018; Wuttig et al. 2019). The seaFAST contains a Nobias-chelate PA1 resin column (ethylenediaminetriacete and iminodiacetate) suitable for the simultaneous preconcentration of several trace metals (Fe, Mn, Zn, Cu, Co, Cd, Ni) with high sensitivity and quantitative recovery (Sohrin et al. 2008; Biller and Bruland 2012). Adjusted seaFAST software settings were a 17 second load loop time and a single 10mL load cycle. Process blanks consisted of pH 2 HCl (Optima, Fisher Scientific) and were processed as samples were to account for any contamination introduced by instrument processing. Instrument Name: SeaFAST Automated Preconcentration System Instrument Short Name: Instrument Description: The seaFAST is an automated sample introduction system for analysis of seawater and other high matrix samples for analyses by ICPMS (Inductively Coupled Plasma Mass Spectrometry).
Cruise: NBP1801
NBP1801
Community Standard Description
International Council for the Exploration of the Sea
RVIB Nathaniel B. Palmer
vessel
NBP1801
Giacomo DiTullio
College of Charleston
https://service.rvdata.us/data/cruise/NBP1801/doc/NBP1801DATA.pdf
Report describing NBP1801
Community Standard Description
International Council for the Exploration of the Sea
RVIB Nathaniel B. Palmer
vessel