http://lod.bco-dmo.org/id/dataset/811547
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
2020-05-14
ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
ISO 19115-2:2009(E)
High and low molecular weight (HMW, LMW) DOC 14C collected from the North Pacific Subtropical Gyre and Central North Atlantic
2020-05-14
publication
2020-05-14
revision
Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA)
2020-05-20
publication
https://doi.org/10.26008/1912/bco-dmo.811547.1
Matthew D. McCarthy
University of California-Santa Cruz
principalInvestigator
Thomas Guilderson
University of California-Santa Cruz
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: McCarthy, M., Guilderson, T. (2020) High and low molecular weight (HMW, LMW) DOC 14C collected from the North Pacific Subtropical Gyre and Central North Atlantic. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2020-05-14 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.811547.1 [access date]
HMW and LMW DOC 14C Dataset Description: <p>High and low molecular weight (HMW, LMW) DOC 14C collected from the North Pacific Subtropical Gyre and Central North Atlantic. These data were published in Broek et al. (2019) and Broek et al. (2017).</p> Methods and Sampling: <p><strong>Sample Collection</strong><br />
Samples were collected on two separate research cruises aboard the R/V Kilo Moana in August 2014 and May 2015. Sampling was conducted at the Hawaii Ocean Time Series Station ALOHA (A Long-Term Oligotrophic Habitat Assessment; 22° 45'N, 158° 00'W) and the Bermuda Atlantic Time Series Site (BATS; 31° 40'N, 64° 10'W) in the Central North Atlantic.</p>
<p>Surface water was sampled via the vessel's underway sampling system. The intake pipe is situated on the forward starboard hull section of the vessel approximately 7.5 m below the waterline. The laboratory seawater tap was allowed to flush for 2 hours prior to each sampling. Seawater was pre-filtered through 53 µm Nitex mesh, and pumped through a 0.2 µm polyethersulfone (PES) cartridge filter (Shelco Filters, Micro Vantage, water grade, 9.75" DOE, polycarbonate housing) prior to introduction to the ultrafiltration system. Large volume subsurface water samples were collected using successive casts of a rosette equipped with 24 x 12 L Niskin bottles.</p>
<p><strong>Tangential-Flow Ultrafiltration</strong><br />
The main UF system was constructed using a modified design of the system described in Roland et al. (2009), and expanded on by Walker et al. (2011). Briefly, the system was comprised of four-spiral wound PES UF membranes, having a nominal molecular weight cut off of 2.5 kD (GE Osmonics GH2540F30, 40-inch long, 2.5-inch diameter). The membranes were mounted in stainless steel housings, plumbed in parallel to a 100 L fluorinated HDPE reservoir, with flow driven by a 1.5 HP stainless steel centrifugal pump (Goulds Pumps, Stainless steel centrifugal pump, NPE series 1 x 1-1/4 -6, close coupled to a 1-1/2 horsepower, 3500 RPM, 60 Hz, 3 phase, Open Drip Proof Motor; 5.75 Inch Impeller Diameter, Standard Viton Mechanical Seals). All other system plumbing components contacting seawater were composed of polytetrafluoroethylene (PTFE) or stainless steel.</p>
<p>The system was run continuously at a membrane pressure of 40-50 psi, resulting in permeation flow rates of 1-2 L/min, depending primarily on the temperature of the feed seawater. Sample water was fed into the system using peristaltic pumps and platinum cured silicone tubing at a flow rate matched to the system permeation rates to ensure a constant system volume of approximately 100 L.</p>
<p>Seawater samples of 3000-4000 L were concentrated to a final retentate volume of 15-20 L, drained from the system into acid washed PC carboys and refrigerated (less than 12 hours at 2C) until the next phase of processing. Samples requiring storage for longer than 12 hours were frozen and stored at -20°C. The UF system was then reconfigured to a smaller volume system, consisting of a single membrane having a smaller nominal molecular weight cutoff (GE Osmonics GE2540F30, 40-inch long, 2.5-inch diameter, 1 kD MWCO), and a 2.5 L PES reservoir for further volume reduction and subsequent salt removal (diafiltration). Using this smaller system, samples were reduced to 2-3 L under lower pressure (25 psi, permeation rate = 250 mL/min). Samples were then diafiltered using 40 L of 18.2 MΩ Milli-Q (ultrapure) water, adding water to the sample retentate reservoir at the same rate of membrane permeation. Reduced and diafiltered samples were stored in acid washed PC bottles at -20°C for transport. In the laboratory, samples were further concentrated by rotary evaporation using pre-combusted glassware (450 °C, 5 h). A molecular sieve and a liquid nitrogen trap were placed between the vacuum pump and rotovap chamber to ensure no contamination of isolated material by back streaming of hydrocarbons or other contaminants. After reduction to 50-100 mL, samples were dried to powder via centrifugal evaporation in PTFE centrifuge tubes. Dry material was homogenized with an ethanol cleaned agate mortar and pestle, transferred to pre-combusted glass vials, and stored in a desiccation cabinet until subsequent analyses.</p>
<p><strong>Solid Phase Extraction</strong><br />
Solid phase extraction was conducted using PPL sorbent (Agilent Bondesil PPL, 125 µm particle size, part # 5982-0026) following the general recommendations of Dittmar et al. (2008) and Green et al. (2014), including loading rates, seawater to sorbent ratios, and elution volumes and rates. Between 300 and 500 g of sorbent was used for each extraction, depending on sample volume and DOC concentration, with average loading of 4.2 ± 1.5 L UF permeate per g sorbent representing 1.9 ± 0.6 mg DOC per g sorbent or a DOC to sorbent mass ratio of 1:600 ± 200. This is in line with both the recommendations of Dittmar et al. (2008) (maximum loading = 10 L seawater per g sorbent) and Li et al. (2016) (DOC to sorbent ratio = 1:800). Permeate from the UF system was fed through PTFE tubing to a pair of 200 L HDPE barrels. The permeate water was then acidified in 200 L batches to pH 2 by adding 400 mL of 6 M HCl (Fisher Chemical, ACS Plus grade). Batch samples were mixed continuously during collection, acidification, and loading using a peristaltic pump and platinum cured Si and PTFE tubing positioned at the surface and bottom of each barrel. Acidified batches of seawater permeate were then pumped through the SPE sorbent. SPE flow rates were matched to UF permeation rates (1-2 L/min), such that a pair of 200 L barrels allowed one barrel to be filled while the contents of the other was passed through the sorbent.</p>
<p>Three custom SPE column configurations were used to contain the sorbent material. The column configuration was modified several times for ease of use on subsequent cruises. First, an open, gravity fed, large (49 mm ID x 1000 mm length, 1875 mL volume) glass chromatography column with 40 µm fritted disk and PTFE stopcock (Kimble-Chase, Kontes) was used. Next, we tested a custom built high-pressure SS housing (10 cm ID x 3.5 cm bed height), and finally a parallel combination of 2 medium-pressure glass chromatography columns (Kimble-Chase, Kontes, Chromaflex LC, 4.8 mm ID x 30 cm, 543 mL volume). While all designs proved to be functionally equivalent, the latter parallel combination of 2 medium-pressure glass columns ultimately provided the best configuration in order to maximize flow rates while simultaneously optimizing the ratio of sorbent bed height to loading speed. Further, the commercial availability and ease of use associated with this configuration made it our preferred design.</p>
<p>Following sample loading, the SPE sorbent was desalted with 6 L of pH 2 ultrapure water at a low flow rate (250-300 mL/min). After desalting, the SPE sorbent was transferred to a glass chromatography column (75 mm ID x 300 mm length, 40 µm fritted disk, PTFE stopcock) with ultrapure water rinses to ensure quantitative transfer. Isolated organic material was then eluted from the sorbent with five to six 500 mL additions of methanol. The eluted methanol solution was stored in pre-combusted amber glass bottles at -20°C for transport. Similar to UF samples, the methanol-eluted solutions were first reduced by rotary evaporation to 50-100 mL. Samples were then dried to powder via centrifugal evaporation in PTFE centrifuge tubes. Dry material was homogenized with an ethanol cleaned agate mortar and pestle, transferred to pre-combusted glass vials, and stored in a desiccation cabinet until elemental and isotopic analyses.</p>
<p><strong>Elemental and Isotopic Analyses</strong><br />
Natural abundance radiocarbon (Δ14C) determinations of all isolated fractions were performed at the Lawrence Livermore National Laboratory, Center for Accelerator Mass Spectrometry (LLNL-CAMS) by AMS following standard graphitization procedures (Santos et al., 2007; Vogel et al., 1984). The Δ14C signature of total seawater DOC (&lt; 0.2 µm) was determined by UV-oxidation and AMS at the UC Irvine Keck Carbon Cycle AMS Lab (Beaupré et al., 2007; Druffel et al., 2013; Walker et al., 2016). Results are reported as age-corrected Δ14C (‰) for geochemical samples and have been corrected to the date of collection and are reported in accordance with conventions set forth by Stuiver and Polach (1977). Isotopic 14C results are reported as background and 13C corrected fraction modern (Fm), Δ14C, and conventional radiocarbon age (ybp).</p>
<p>Stable carbon (δ13C) and nitrogen (δ15N) isotope ratios were determined via elemental analyzer isotope ratio mass spectrometry (EA-IRMS) at the University of California, Santa Cruz, Stable Isotope Laboratory (UCSC-SIL; <a href="http://emerald.ucsc.edu/~silab/" target="_blank">http://emerald.ucsc.edu/~silab/</a>). Approximately 1 mg of each dry isolated DOM sample was weighed into tin capsules (Costec, 5 x 9 mm) for analysis. EA-IRMS analysis was conducted using a Carlo Erba CHNS-O EA1108-elemental analyzer interfaced via a ConFlo III device with a ThermoFinnigan Delta Plus XP isotope ratio mass spectrometer (Thermo Fisher Scientific).&nbsp; Standards, EA-IRMS protocols, and correction routines followed standard UCSC-SIL protocols. Analytical uncertainties of n=3 replicate measurements of isotopic standards ranged from ± 0.05 to 0.1‰ for both δ13C and δ15N. Carbon to nitrogen elemental ratios were similarly determined by elemental analysis. The presented ratios are atomic ratios (C/N)a normalized to the mass of C and N, but have been abbreviated as C/N throughout.</p>
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1358041 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1358041
completed
Matthew D. McCarthy
University of California-Santa Cruz
831-459-1533
1156 High Street
Santa Cruz
CA
95064
USA
mdmccar@ucsc.edu
pointOfContact
Thomas Guilderson
University of California-Santa Cruz
925-422-1753
Ocean Sciences Department 1156 High St
Santa Cruz
CA
95060
USA
tguilder@ucsc.edu
pointOfContact
asNeeded
Dataset Version: 1
Unknown
location
year
season
sample_type
depth
CAMS_num
Fm
Fm_stdev
d14C
d14C_stdev
C14_age
C14_age_stdev
Carlo Erba CHNS-O EA1108-elemental analyzer
ThermoFinnigan Delta Plus XP isotope ratio mass spectrometer (Thermo Fisher Scientific)
rosette equipped with 24 x 12 L Niskin bottles
underway sampling system
theme
None, User defined
site
year
season
sample type
depth
sample identification
Elemental carbon (C)
age
featureType
BCO-DMO Standard Parameters
Elemental Analyzer
Isotope-ratio Mass Spectrometer
Niskin bottle
Pump - Surface Underway Ship Intake
instrument
BCO-DMO Standard Instruments
KM1506
KM1515
AE1520
AE1608
KM1418
service
Deployment Activity
Central North Pacific, Station ALOHA
Tropical Pacific
Bermuda
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.
The Microbial Nitrogen Pump: Coupling 14C and Compound-specific Amino Acids to Understand the Role of Microbial Transformations in the Refractory Ocean DON Pool
https://osprey.bco-dmo.org/project/701744
The Microbial Nitrogen Pump: Coupling 14C and Compound-specific Amino Acids to Understand the Role of Microbial Transformations in the Refractory Ocean DON Pool
<p>Dissolved organic nitrogen is one of the most important - but perhaps least understood - components of the modern ocean nitrogen cycle. While dissolved organic nitrogen represents a main active reservoir of fixed and seemingly biologically-available nitrogen, at the same time most of ocean's dissolved organic nitrogen pool is also apparently unavailable for use by organisms. Recently, the idea of the "Microbial Carbon Pump" has emerged, providing a renewed focus on microbes as primary agents for the formation of biologically-available dissolved material. However, the role that microbes play in transformation of biologically-available dissolved organic nitrogen is still lacking. In order to fill gaps in this knowledge, researchers from the University of California Santa Cruz will apply a series of new analytical approaches to test the role of microbial source and transformation in formation of the ocean's biologically-available dissolved organic nitrogen pool. Results from this study will address one of the major unknowns of both chemical oceanography and the ocean nitrogen cycle.</p>
<p>Broader Impacts:<br />
This proposal will provide oceanographers new tools to test ideas of microbial organic matter sequestration in a world where the oceans are rapidly changing. High school, undergraduate, graduate and post-doctoral education will be furthered through active participation in lab, field, and data synthesis activities.</p>
DON Microbial Nitrogen Pump
largerWorkCitation
project
eng; USA
oceans
Central North Pacific, Station ALOHA; Tropical Pacific; Bermuda
-158
-64.1667
22.75
31.6667
2014-01-01
2016-12-31
North Pacific Subtropical Gyre (HOT station), North Atlantic Subtropical Gyre (BATS time series station), California Margin
0
BCO-DMO catalogue of parameters from High and low molecular weight (HMW, LMW) DOC 14C collected from the North Pacific Subtropical Gyre and Central North Atlantic
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/811564.rdf
Name: location
Units: unitless
Description: <p>Sample collection location. HOT = Hawaii Ocean Time Series station ALOHA (22° 45'N, 158° 00'W) in North Pacific Subtropical Gyre (NPSG); BATS = Hawaii Ocean Time Series station ALOHA (22° 45'N, 158° 00'W) in North Pacific Subtropical Gyre (NPSG)</p>
http://lod.bco-dmo.org/id/dataset-parameter/811565.rdf
Name: year
Units: unitless
Description: <p>Year of sample collection; format: YYYY</p>
http://lod.bco-dmo.org/id/dataset-parameter/811566.rdf
Name: season
Units: unitless
Description: <p>Season of sample collection</p>
http://lod.bco-dmo.org/id/dataset-parameter/811567.rdf
Name: sample_type
Units: unitless
Description: <p>DOM Fraction</p>
http://lod.bco-dmo.org/id/dataset-parameter/811568.rdf
Name: depth
Units: meters (m)
Description: <p>Sample depth</p>
http://lod.bco-dmo.org/id/dataset-parameter/811569.rdf
Name: CAMS_num
Units: unitless
Description: <p>CAMS AMS analysis #</p>
http://lod.bco-dmo.org/id/dataset-parameter/811570.rdf
Name: Fm
Units: unitless
Description: <p>14C derived fraction modern</p>
http://lod.bco-dmo.org/id/dataset-parameter/811571.rdf
Name: Fm_stdev
Units: unitless
Description: <p>Standard deviation of Fm</p>
http://lod.bco-dmo.org/id/dataset-parameter/811572.rdf
Name: d14C
Units: permil (‰)
Description: <p>14C/12C isotopic ratio</p>
http://lod.bco-dmo.org/id/dataset-parameter/811573.rdf
Name: d14C_stdev
Units: permil (‰)
Description: <p>Standard deviation of d14C</p>
http://lod.bco-dmo.org/id/dataset-parameter/811574.rdf
Name: C14_age
Units: years before present
Description: <p>14C derived age</p>
http://lod.bco-dmo.org/id/dataset-parameter/811575.rdf
Name: C14_age_stdev
Units: years before present
Description: <p>Standard deviation of C14_age</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
2875
https://darchive.mblwhoilibrary.org/bitstream/1912/25794/1/dataset-811547_hmw-and-lmw-doc-14c__v1.tsv
download
https://doi.org/10.26008/1912/bco-dmo.811547.1
download
onLine
dataset
<p><strong>Sample Collection</strong><br />
Samples were collected on two separate research cruises aboard the R/V Kilo Moana in August 2014 and May 2015. Sampling was conducted at the Hawaii Ocean Time Series Station ALOHA (A Long-Term Oligotrophic Habitat Assessment; 22° 45'N, 158° 00'W) and the Bermuda Atlantic Time Series Site (BATS; 31° 40'N, 64° 10'W) in the Central North Atlantic.</p>
<p>Surface water was sampled via the vessel's underway sampling system. The intake pipe is situated on the forward starboard hull section of the vessel approximately 7.5 m below the waterline. The laboratory seawater tap was allowed to flush for 2 hours prior to each sampling. Seawater was pre-filtered through 53 µm Nitex mesh, and pumped through a 0.2 µm polyethersulfone (PES) cartridge filter (Shelco Filters, Micro Vantage, water grade, 9.75" DOE, polycarbonate housing) prior to introduction to the ultrafiltration system. Large volume subsurface water samples were collected using successive casts of a rosette equipped with 24 x 12 L Niskin bottles.</p>
<p><strong>Tangential-Flow Ultrafiltration</strong><br />
The main UF system was constructed using a modified design of the system described in Roland et al. (2009), and expanded on by Walker et al. (2011). Briefly, the system was comprised of four-spiral wound PES UF membranes, having a nominal molecular weight cut off of 2.5 kD (GE Osmonics GH2540F30, 40-inch long, 2.5-inch diameter). The membranes were mounted in stainless steel housings, plumbed in parallel to a 100 L fluorinated HDPE reservoir, with flow driven by a 1.5 HP stainless steel centrifugal pump (Goulds Pumps, Stainless steel centrifugal pump, NPE series 1 x 1-1/4 -6, close coupled to a 1-1/2 horsepower, 3500 RPM, 60 Hz, 3 phase, Open Drip Proof Motor; 5.75 Inch Impeller Diameter, Standard Viton Mechanical Seals). All other system plumbing components contacting seawater were composed of polytetrafluoroethylene (PTFE) or stainless steel.</p>
<p>The system was run continuously at a membrane pressure of 40-50 psi, resulting in permeation flow rates of 1-2 L/min, depending primarily on the temperature of the feed seawater. Sample water was fed into the system using peristaltic pumps and platinum cured silicone tubing at a flow rate matched to the system permeation rates to ensure a constant system volume of approximately 100 L.</p>
<p>Seawater samples of 3000-4000 L were concentrated to a final retentate volume of 15-20 L, drained from the system into acid washed PC carboys and refrigerated (less than 12 hours at 2C) until the next phase of processing. Samples requiring storage for longer than 12 hours were frozen and stored at -20°C. The UF system was then reconfigured to a smaller volume system, consisting of a single membrane having a smaller nominal molecular weight cutoff (GE Osmonics GE2540F30, 40-inch long, 2.5-inch diameter, 1 kD MWCO), and a 2.5 L PES reservoir for further volume reduction and subsequent salt removal (diafiltration). Using this smaller system, samples were reduced to 2-3 L under lower pressure (25 psi, permeation rate = 250 mL/min). Samples were then diafiltered using 40 L of 18.2 MΩ Milli-Q (ultrapure) water, adding water to the sample retentate reservoir at the same rate of membrane permeation. Reduced and diafiltered samples were stored in acid washed PC bottles at -20°C for transport. In the laboratory, samples were further concentrated by rotary evaporation using pre-combusted glassware (450 °C, 5 h). A molecular sieve and a liquid nitrogen trap were placed between the vacuum pump and rotovap chamber to ensure no contamination of isolated material by back streaming of hydrocarbons or other contaminants. After reduction to 50-100 mL, samples were dried to powder via centrifugal evaporation in PTFE centrifuge tubes. Dry material was homogenized with an ethanol cleaned agate mortar and pestle, transferred to pre-combusted glass vials, and stored in a desiccation cabinet until subsequent analyses.</p>
<p><strong>Solid Phase Extraction</strong><br />
Solid phase extraction was conducted using PPL sorbent (Agilent Bondesil PPL, 125 µm particle size, part # 5982-0026) following the general recommendations of Dittmar et al. (2008) and Green et al. (2014), including loading rates, seawater to sorbent ratios, and elution volumes and rates. Between 300 and 500 g of sorbent was used for each extraction, depending on sample volume and DOC concentration, with average loading of 4.2 ± 1.5 L UF permeate per g sorbent representing 1.9 ± 0.6 mg DOC per g sorbent or a DOC to sorbent mass ratio of 1:600 ± 200. This is in line with both the recommendations of Dittmar et al. (2008) (maximum loading = 10 L seawater per g sorbent) and Li et al. (2016) (DOC to sorbent ratio = 1:800). Permeate from the UF system was fed through PTFE tubing to a pair of 200 L HDPE barrels. The permeate water was then acidified in 200 L batches to pH 2 by adding 400 mL of 6 M HCl (Fisher Chemical, ACS Plus grade). Batch samples were mixed continuously during collection, acidification, and loading using a peristaltic pump and platinum cured Si and PTFE tubing positioned at the surface and bottom of each barrel. Acidified batches of seawater permeate were then pumped through the SPE sorbent. SPE flow rates were matched to UF permeation rates (1-2 L/min), such that a pair of 200 L barrels allowed one barrel to be filled while the contents of the other was passed through the sorbent.</p>
<p>Three custom SPE column configurations were used to contain the sorbent material. The column configuration was modified several times for ease of use on subsequent cruises. First, an open, gravity fed, large (49 mm ID x 1000 mm length, 1875 mL volume) glass chromatography column with 40 µm fritted disk and PTFE stopcock (Kimble-Chase, Kontes) was used. Next, we tested a custom built high-pressure SS housing (10 cm ID x 3.5 cm bed height), and finally a parallel combination of 2 medium-pressure glass chromatography columns (Kimble-Chase, Kontes, Chromaflex LC, 4.8 mm ID x 30 cm, 543 mL volume). While all designs proved to be functionally equivalent, the latter parallel combination of 2 medium-pressure glass columns ultimately provided the best configuration in order to maximize flow rates while simultaneously optimizing the ratio of sorbent bed height to loading speed. Further, the commercial availability and ease of use associated with this configuration made it our preferred design.</p>
<p>Following sample loading, the SPE sorbent was desalted with 6 L of pH 2 ultrapure water at a low flow rate (250-300 mL/min). After desalting, the SPE sorbent was transferred to a glass chromatography column (75 mm ID x 300 mm length, 40 µm fritted disk, PTFE stopcock) with ultrapure water rinses to ensure quantitative transfer. Isolated organic material was then eluted from the sorbent with five to six 500 mL additions of methanol. The eluted methanol solution was stored in pre-combusted amber glass bottles at -20°C for transport. Similar to UF samples, the methanol-eluted solutions were first reduced by rotary evaporation to 50-100 mL. Samples were then dried to powder via centrifugal evaporation in PTFE centrifuge tubes. Dry material was homogenized with an ethanol cleaned agate mortar and pestle, transferred to pre-combusted glass vials, and stored in a desiccation cabinet until elemental and isotopic analyses.</p>
<p><strong>Elemental and Isotopic Analyses</strong><br />
Natural abundance radiocarbon (Δ14C) determinations of all isolated fractions were performed at the Lawrence Livermore National Laboratory, Center for Accelerator Mass Spectrometry (LLNL-CAMS) by AMS following standard graphitization procedures (Santos et al., 2007; Vogel et al., 1984). The Δ14C signature of total seawater DOC (&lt; 0.2 µm) was determined by UV-oxidation and AMS at the UC Irvine Keck Carbon Cycle AMS Lab (Beaupré et al., 2007; Druffel et al., 2013; Walker et al., 2016). Results are reported as age-corrected Δ14C (‰) for geochemical samples and have been corrected to the date of collection and are reported in accordance with conventions set forth by Stuiver and Polach (1977). Isotopic 14C results are reported as background and 13C corrected fraction modern (Fm), Δ14C, and conventional radiocarbon age (ybp).</p>
<p>Stable carbon (δ13C) and nitrogen (δ15N) isotope ratios were determined via elemental analyzer isotope ratio mass spectrometry (EA-IRMS) at the University of California, Santa Cruz, Stable Isotope Laboratory (UCSC-SIL; <a href="http://emerald.ucsc.edu/~silab/" target="_blank">http://emerald.ucsc.edu/~silab/</a>). Approximately 1 mg of each dry isolated DOM sample was weighed into tin capsules (Costec, 5 x 9 mm) for analysis. EA-IRMS analysis was conducted using a Carlo Erba CHNS-O EA1108-elemental analyzer interfaced via a ConFlo III device with a ThermoFinnigan Delta Plus XP isotope ratio mass spectrometer (Thermo Fisher Scientific).&nbsp; Standards, EA-IRMS protocols, and correction routines followed standard UCSC-SIL protocols. Analytical uncertainties of n=3 replicate measurements of isotopic standards ranged from ± 0.05 to 0.1‰ for both δ13C and δ15N. Carbon to nitrogen elemental ratios were similarly determined by elemental analysis. The presented ratios are atomic ratios (C/N)a normalized to the mass of C and N, but have been abbreviated as C/N throughout.</p>
Specified by the Principal Investigator(s)
<p>14C Results are reported as age-corrected Δ14C (‰) for geochemical samples and have been corrected to the date of collection and are reported in accordance with conventions set forth by Stuiver and Polach (1977).</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
Carlo Erba CHNS-O EA1108-elemental analyzer
Carlo Erba CHNS-O EA1108-elemental analyzer
PI Supplied Instrument Name: Carlo Erba CHNS-O EA1108-elemental analyzer Instrument Name: Elemental Analyzer Instrument Short Name: Instrument Description: Instruments that quantify carbon, nitrogen and sometimes other elements by combusting the sample at very high temperature and assaying the resulting gaseous oxides. Usually used for samples including organic material. Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/LAB01/
ThermoFinnigan Delta Plus XP isotope ratio mass spectrometer (Thermo Fisher Scientific)
ThermoFinnigan Delta Plus XP isotope ratio mass spectrometer (Thermo Fisher Scientific)
PI Supplied Instrument Name: ThermoFinnigan Delta Plus XP isotope ratio mass spectrometer (Thermo Fisher Scientific) Instrument Name: Isotope-ratio Mass Spectrometer Instrument Short Name:IR Mass Spec; IRMS Instrument Description: The Isotope-ratio Mass Spectrometer is a particular type of mass spectrometer used to measure the relative abundance of isotopes in a given sample (e.g. VG Prism II Isotope Ratio Mass-Spectrometer). Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/LAB16/
rosette equipped with 24 x 12 L Niskin bottles
rosette equipped with 24 x 12 L Niskin bottles
PI Supplied Instrument Name: rosette equipped with 24 x 12 L Niskin bottles 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/
underway sampling system
underway sampling system
PI Supplied Instrument Name: underway sampling system Instrument Name: Pump - Surface Underway Ship Intake Instrument Short Name:Pump-Ship Intake Instrument Description: The 'Pump-underway ship intake' system indicates that samples are from the ship's clean water intake pump. This is essentially a surface water sample from a source of uncontaminated near-surface (commonly 3 to 7 m) seawater that can be pumped continuously to shipboard laboratories on research vessels. There is typically a temperature sensor near the intake (known as the hull temperature) to provide measurements that are as close as possible to the ambient water temperature. The flow from the supply is typically directed through continuously logged sensors such as a thermosalinograph and a fluorometer. Water samples are often collected from the underway supply that may also be referred to as the non-toxic supply. Ideally the data contributor has specified the depth in the ship's hull at which the pump is mounted. Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/31/
Cruise: KM1506
KM1506
R/V Kilo Moana
Community Standard Description
International Council for the Exploration of the Sea
R/V Kilo Moana
vessel
KM1506
Hilary G. Close
University of Hawai'i
Cruise: KM1515
KM1515
R/V Kilo Moana
Community Standard Description
International Council for the Exploration of the Sea
R/V Kilo Moana
vessel
KM1515
Brian N. Popp
University of Hawai'i
Cruise: AE1520
AE1520
R/V Atlantic Explorer
Community Standard Description
International Council for the Exploration of the Sea
R/V Atlantic Explorer
vessel
AE1520
Matthew Enright
Bermuda Institute of Ocean Sciences
Cruise: AE1608
AE1608
R/V Atlantic Explorer
Community Standard Description
International Council for the Exploration of the Sea
R/V Atlantic Explorer
vessel
AE1608
Rodney J. Johnson
Bermuda Institute of Ocean Sciences
Cruise: KM1418
KM1418
R/V Kilo Moana
Community Standard Description
International Council for the Exploration of the Sea
R/V Kilo Moana
vessel
KM1418
Jeffrey C. Drazen
University of Hawaiʻi at Mānoa
R/V Kilo Moana
Community Standard Description
International Council for the Exploration of the Sea
R/V Kilo Moana
vessel
R/V Atlantic Explorer
Community Standard Description
International Council for the Exploration of the Sea
R/V Atlantic Explorer
vessel