http://lod.bco-dmo.org/id/dataset/832995
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
2020-12-03
ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
ISO 19115-2:2009(E)
Natural abundance N2O isotopomers measured from seawater samples collected in the Eastern Tropical North Pacific during R/V Sally Ride (SR1805) cruise from March to April 2018
2020-08-02
publication
2020-08-02
revision
Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA)
2021-08-11
publication
https://doi.org/10.26008/1912/bco-dmo.832995.1
Karen L. Casciotti
Stanford University
principalInvestigator
Pascale A. Baya
Stanford University
principalInvestigator
Colette LaMonica Kelly
Stanford University
principalInvestigator
Nicole M. Travis
Stanford University
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: Kelly, C. L., Travis, N. M., Baya, P. A., Casciotti, K. L. (2021) Natural abundance N2O isotopomers measured from seawater samples collected in the Eastern Tropical North Pacific during R/V Sally Ride (SR1805) cruise from March to April 2018. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2020-08-02 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.832995.1 [access date]
N2O Natural Abundance Isotopomers in ETNP Dataset Description: Methods and Sampling: <p>Seawater samples for dissolved nitrate, nitrite, and nitrous oxide isotope analysis were collected from either a 30-liter, 12-bottle rosette or a 12-liter, 24-bottle rosette. Samples for nitrate and nitrite isotopic analysis were collected, unfiltered, into 500 mL Nalgene polypropylene bottles following three rinses of the bottle, caps, and threads of at least 10% of the bottle volume. After collection from the rosette, samples for nitrate isotopic analysis were syringe-filtered with a 60 mL syringe through a 0.22 µM pore size Sterivex filter into 60-mL high density polyethylene bottles, then frozen at –20ºC</p>
<p>For<strong> nitrite isotopic analysis</strong>, samples were preserved within two hours of collection for δ<sup>15</sup>N-NO<sub>2</sub><sup>-</sup> and δ<sup>18</sup>O-NO<sub>2</sub><sup>-</sup> using the azide method (McIlvin and Altabet, 2005), along with nitrite isotope reference materials (Casciotti et al., 2007) in different amounts. Briefly, seawater samples were added to 20 mL vials in volumes targeted to achieve 10 nmol nitrite, based on shipboard colorimetric nitrite analysis (Grasshoff et al., 1999), then capped with a gray butyl septum (National Scientific) and sealed with an aluminum crimp seal. Where [NO<sub>2</sub><sup>–</sup>] &gt; 0.25 µM (limit of detection for these analyses, Figure S1 in Kelly et al, 2020) but &lt; 2 µM, the maximum volume allowable for analysis (10 mL) seawater was subsampled, regardless of actual nitrite concentration. Reference materials (Table S1, Kelly et al., 2020) were diluted into nitrite-free seawater and prepared in 5 nmol and 10 nmol amounts to bracket low-nitrite samples. Vials were purged with N<sub>2</sub> gas for 15 minutes to remove background N<sub>2</sub>O, then treated with a sparged sodium azide/acetic acid solution to chemically convert dissolved nitrite into N<sub>2</sub>O. The reaction was halted after 30 minutes with the addition of 6 M sodium hydroxide solution (McIlvin and Altabet, 2005).</p>
<p>For <strong>nitrous oxide isotopic analysis</strong>, samples were collected into 160 mL glass serum bottles (Wheaton), following standard gas-sampling procedures: gas-tight tubing (Tygon) was used to overflow each serum bottle with sample three times, after which a ~1 mL air headspace was introduced, and the bottle was capped with a gray butyl septum (National Scientific). Given the trace amount of N<sub>2</sub>O in the atmosphere (NOAA Global Monitoring Laboratory) and complete flushing of the bottle during analysis, the effect of this headspace and N<sub>2</sub>O partitioning between the gas and liquid phase falls within the analytical uncertainty for N<sub>2</sub>O concentration measurements. Samples for N<sub>2</sub>O isotopic analysis were promptly preserved by adding 100 µL mercuric chloride (HgCl<sub>2</sub>) to each 160 mL bottle, then sealed with an aluminum crimp seal and stored at lab temperature (20-22ºC).</p>
<p>&nbsp;</p>
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1657868 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1657868
completed
Karen L. Casciotti
Stanford University
650-721-5545
Department of Environmental Earth System Science 473 Via Ortega, Y2E2 Building, Room 140
Stanford
CA
94305
USA
kcasciotti@stanford.edu
pointOfContact
Pascale A. Baya
Stanford University
Department of Earth System Science 473 Via Ortega, Y2E2 Building, Room 140
Stanford
CA
94305
United States
abaya@stanford.edu
pointOfContact
Colette LaMonica Kelly
Stanford University
802-595-3647
Department of Earth System Science 473 Via Ortega, Y2E2 Building, Room 140
Stanford
CA
94305
United States
clkelly@stanford.edu
pointOfContact
Nicole M. Travis
Stanford University
Department of Earth System Science 473 Via Ortega, Y2E2 Building, Room 140
Stanford
CA
94305
United States
ntravis@stanford.edu
pointOfContact
asNeeded
Dataset Version: 1
Unknown
ISO_DateTime_UTC
Station
Cast
Target_Depth
Niskin
Latitude
Longitude
CTD_Pressure
CTD_Depth
Sigma_theta
Salinity
PAR
Seabird_Oxygen
Temperature
Nitrite
Nitrate_Sample_ID
Sulfamic_treated
NO3_rep1
NO3_rep2
NO3_rep3
NO3_mean
NO3_std
d18O_NO3_meas1
d18O_NO3_meas2
d18O_NO3_meas3
d18O_NO3_avg
d18O_NO3_stdev
d15N_NO3_meas1
d15N_NO3_meas2
d15N_NO3_meas3
d15N_NO3_avg
d15N_NO3_stdev
d18O_NO2_rep1
d18O_NO2_rep2
d18O_NO2_avg
d15N_NO2_rep1
d15N_NO2_rep2
d15N_NO2_avg
N2O_sat
N2O_rep1
N2O_rep2
N2O_mean
N2O_std
N2O_supersaturation_rep1
N2O_supersaturation_rep2
N2O_supersaturation_mean
N2O_supersaturation_std
d18O_N2O_rep1
d18O_N2O_rep2
d18O_N2O_mean
d18O_N2O_std
d15N_alpha_N2O_rep1
d15N_alpha_N2O_rep2
d15N_alpha_N2O_mean
d15N_alpha_N2O_std
d15N_beta_N2O_rep1
d15N_beta_N2O_rep2
d15N_beta_N2O_mean
d15N_beta_N2O_std
d15N_N2Obulk_rep1
d15N_N2Obulk_rep2
d15N_N2Obulk_mean
d15N_N2Obulk_std
SP_1
SP_2
SP_mean
SP_std
N2O_Flag_1
N2O_Flag_2
Westco discrete analyzer system
Thermo Finnigan DELTA V isotope ratio mass spectrometer
theme
None, User defined
ISO_DateTime_UTC
station
cast
depth
bottle number
latitude
longitude
water pressure
sigma-theta
salinity
PAR
dissolved Oxygen
water temperature at measurement depth
Nitrite
sample identification
treatment
Nitrate
mean
standard deviation
d18O_NO3
d15N_NO3
oxygen 16 to oxygen 18 ratio
d15N
Nitrous Oxide
quality flag
featureType
BCO-DMO Standard Parameters
Discrete Analyzer
Isotope-ratio Mass Spectrometer
instrument
BCO-DMO Standard Instruments
SR1805
service
Deployment Activity
Eastern Tropical North Pacific 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: Mechanisms and Controls of Nitrous Oxide Production in the Eastern Tropical North Pacific Ocean
https://osprey.bco-dmo.org/project/741018
Collaborative Research: Mechanisms and Controls of Nitrous Oxide Production in the Eastern Tropical North Pacific Ocean
<p><em>NSF Award Abstract:</em><br />
Nitrous oxide (N2O) is present at very low concentrations in the atmosphere but is an important greenhouse gas and ozone destroying substance. As with other climate-active gases like methane and carbon dioxide, human activities are responsible for most of its production, either directly through fossil fuel burning or agricultural activities. However, about a third of natural N2O emissions come from the ocean, but even these emissions can be indirectly affected by human activities. About half of the ocean source is derived from three specific geographic regions in the Pacific Ocean and Arabian Sea. These three oceanic regions are places where oxygen concentrations are so low in the intermediate depths that metabolic processes requiring the absence of oxygen are able to occur. These regions are called Oxygen Minimum Zones (OMZs) and they have microbiological processes that occur nowhere else in global ocean waters. In the work proposed here, we will investigate how the microbiological pathways of N2O production and consumption are regulated by environmental conditions such as oxygen and nutrient concentration. This work will involve a research expedition to one of the OMZs, the Eastern Tropical Pacific Ocean off the coast of Mexico. On the cruise, we will perform experiments and collect samples for analysis in our home laboratories at Princeton and Stanford Universities. Advising of graduate students and teaching at the graduate and undergraduate levels at both institutions will be linked to this research. This work is particularly timely because global warming has already indirectly affected the size and geographic extent of the OMZs. Greater expanse of low oxygen water could cause N2O production to increase, leading to increased fluxes of N2O to the atmosphere. In the atmosphere, the role of N2O in ozone destruction and as a greenhouse gas could be critical elements of global change.</p>
<p>Nitrous oxide (N2O) is an important greenhouse gas and ozone destroying substance. About a third of natural N2O emissions come from the ocean, and about half of the ocean source is derived from waters with oxygen deficient intermediate waters (oxygen minimum zones, OMZs). Nitrification is recognized as the main source of N2O in the ocean, but denitrification also likely contributes to the net source in and around OMZs. Because nitrification and denitrification are performed by microbes with very different metabolisms and environmental controls, their contributions to N2O production are expected to differ in response to changes in oxygenation and nutrient inputs. Thus it is important to understand the regulation of N2O production by both processes. The main goal of this project is to quantify the environmental regulation of N2O production and consumption pathways in and around OMZs in order to obtain predictive understanding of N2O distributions and fluxes in the ocean. To do this, production and consumption of N2O will be measured using stable isotope tracer incubations at stations located within and outside one of the major OMZs in the Eastern Tropical North Pacific ocean. The dependence of the rate processes on substrate, product, and oxygen concentrations will be determined, and the composition of the microbial assemblages will be assessed to determine whether different microbial components are involved under different environmental conditions. Natural abundance stable isotope and isotopomer measurements of N2O will be interpreted in concert with measured rates to deduce the sources and pathways (nitrification, nitrifier-denitrification, denitrification, and ?hybrid? formation) involved in N2O production and consumption. This work will also involve a novel application of isotopomer measurements of N2O from incubations to identify the placement of 15N from NH4+ and NO2- within labeled N2O pools.</p>
<p>OMZ regions are the sites of unique nitrogen cycling processes that are critical in determining the fixed nitrogen inventory of the ocean. If OMZs expand as predicted due to anthropogenic changes in the coming decades, changes in these chemical distributions may affect the atmospheric flux of nitrous oxide as well as modify overall ocean productivity via changes in the fixed nitrogen inventory. Understanding the regulation and environmental control of the processes responsible for N2O production and consumption is the foundation of understanding their response to global change.</p>
N2O in ETNP
largerWorkCitation
project
eng; USA
oceans
Eastern Tropical North Pacific Ocean
-112.9998
-102.35
10
17.683
2018-03-13
2018-04-04
Eastern Tropical North Pacific Ocean (oxygen minimum zone)
0
BCO-DMO catalogue of parameters from Natural abundance N2O isotopomers measured from seawater samples collected in the Eastern Tropical North Pacific during R/V Sally Ride (SR1805) cruise from March to April 2018
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/858215.rdf
Name: ISO_DateTime_UTC
Units: unitless
Description: <p>Date and time (UTC) formatted to ISO8601 standard (YYYY-MM-DDThh:mm:ssZ)</p>
http://lod.bco-dmo.org/id/dataset-parameter/858216.rdf
Name: Station
Units: unitless
Description: <p>Station ID</p>
http://lod.bco-dmo.org/id/dataset-parameter/858217.rdf
Name: Cast
Units: unitless
Description: <p>Sequential CTD cast number</p>
http://lod.bco-dmo.org/id/dataset-parameter/858218.rdf
Name: Target_Depth
Units: meters
Description: <p>Target sampling depth</p>
http://lod.bco-dmo.org/id/dataset-parameter/858219.rdf
Name: Niskin
Units: unitless
Description: <p>Bottle number on CTD rosette</p>
http://lod.bco-dmo.org/id/dataset-parameter/858220.rdf
Name: Latitude
Units: decimal degrees
Description: <p>Latitude at start of CTD deployment; South is negative</p>
http://lod.bco-dmo.org/id/dataset-parameter/858221.rdf
Name: Longitude
Units: decimal degrees
Description: <p>Longitude at start of CTD deployment; West is negative</p>
http://lod.bco-dmo.org/id/dataset-parameter/858222.rdf
Name: CTD_Pressure
Units: decibars
Description: <p>Pressure</p>
http://lod.bco-dmo.org/id/dataset-parameter/858223.rdf
Name: CTD_Depth
Units: meters
Description: <p>Depth</p>
http://lod.bco-dmo.org/id/dataset-parameter/858224.rdf
Name: Sigma_theta
Units: kilogram per cubic meter (kg/m^3)
Description: <p>Potential density</p>
http://lod.bco-dmo.org/id/dataset-parameter/858225.rdf
Name: Salinity
Units: practical salinity units (psu)
Description: <p>Salinity</p>
http://lod.bco-dmo.org/id/dataset-parameter/858226.rdf
Name: PAR
Units: micro Einsteins per squared meter (µE/m^2)
Description: <p>Photosynthetically active radiation</p>
http://lod.bco-dmo.org/id/dataset-parameter/858227.rdf
Name: Seabird_Oxygen
Units: micromoles per liter (µmol/L)
Description: <p>Oxygen from Seabird oxygen sensor</p>
http://lod.bco-dmo.org/id/dataset-parameter/858228.rdf
Name: Temperature
Units: degrees Celsius
Description: <p>Water temperature</p>
http://lod.bco-dmo.org/id/dataset-parameter/858229.rdf
Name: Nitrite
Units: micromoles per liter (µmol/L)
Description: <p>Concentration of nitrite</p>
http://lod.bco-dmo.org/id/dataset-parameter/858230.rdf
Name: Nitrate_Sample_ID
Units: unitless
Description: <p>Sample identifier for nitrate isotopes</p>
http://lod.bco-dmo.org/id/dataset-parameter/858231.rdf
Name: Sulfamic_treated
Units: unitless
Description: <p>Whether nitrate isotope sample was sulfamic-treated: 1=yes, 0=no</p>
http://lod.bco-dmo.org/id/dataset-parameter/858232.rdf
Name: NO3_rep1
Units: micromoles per liter (µmol/L)
Description: <p>Concentration of nitrate, first replicate analysis of same sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858233.rdf
Name: NO3_rep2
Units: micromoles per liter (µmol/L)
Description: <p>Concentration of nitrate, second replicate analysis of the same sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858234.rdf
Name: NO3_rep3
Units: micromoles per liter (µmol/L)
Description: <p>Concentration of nitrate, third replicate analysis of the same sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858235.rdf
Name: NO3_mean
Units: micromoles per liter (µmol/L)
Description: <p>Concentration of nitrate, average of replicate analyses</p>
http://lod.bco-dmo.org/id/dataset-parameter/858236.rdf
Name: NO3_std
Units: micromoles per liter (µmol/L)
Description: <p>Concentration of nitrate, standard deviation of replicate analyses</p>
http://lod.bco-dmo.org/id/dataset-parameter/858237.rdf
Name: d18O_NO3_meas1
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrate, first replicate analysis of the same sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858238.rdf
Name: d18O_NO3_meas2
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrate, second replicate analysis of the same sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858239.rdf
Name: d18O_NO3_meas3
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrate, third replicate analysis of the same sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858240.rdf
Name: d18O_NO3_avg
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrate, average of replicate analyses</p>
http://lod.bco-dmo.org/id/dataset-parameter/858241.rdf
Name: d18O_NO3_stdev
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrate, standard deviation of replicate analyses</p>
http://lod.bco-dmo.org/id/dataset-parameter/858242.rdf
Name: d15N_NO3_meas1
Units: per mil vs. atmospheric N2
Description: <p>delta15N of nitrate, first replicate analysis of the same sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858243.rdf
Name: d15N_NO3_meas2
Units: per mil vs. atmospheric N2
Description: <p>delta15N of nitrate, second replicate analysis of the same sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858244.rdf
Name: d15N_NO3_meas3
Units: per mil vs. atmospheric N2
Description: <p>delta15N of nitrate, third replicate analysis of the same sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858245.rdf
Name: d15N_NO3_avg
Units: per mil vs. atmospheric N2
Description: <p>delta15N of nitrate, average of replicate analyses</p>
http://lod.bco-dmo.org/id/dataset-parameter/858246.rdf
Name: d15N_NO3_stdev
Units: per mil vs. atmospheric N2
Description: <p>delta15N of nitrate, standard deviation of replicate analyses</p>
http://lod.bco-dmo.org/id/dataset-parameter/858247.rdf
Name: d18O_NO2_rep1
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrite, first distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858248.rdf
Name: d18O_NO2_rep2
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrite, second distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858249.rdf
Name: d18O_NO2_avg
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrite, average of replicates</p>
http://lod.bco-dmo.org/id/dataset-parameter/858250.rdf
Name: d15N_NO2_rep1
Units: per mil vs. atmospheric N2
Description: <p>delta15N of nitrite, first distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858251.rdf
Name: d15N_NO2_rep2
Units: per mil vs. atmospheric N2
Description: <p>delta15N of nitrite, second distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858252.rdf
Name: d15N_NO2_avg
Units: per mil vs. atmospheric N2
Description: <p>delta15N of nitrite, average of replicates</p>
http://lod.bco-dmo.org/id/dataset-parameter/858253.rdf
Name: N2O_sat
Units: nanomoles per liter (nmol/L)
Description: <p>Saturation concentration of nitrous oxide, calculated from Weiss and Price (1980)</p>
http://lod.bco-dmo.org/id/dataset-parameter/858254.rdf
Name: N2O_rep1
Units: nanomoles per liter (nmol/L)
Description: <p>Concentration of nitrous oxide, first distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858255.rdf
Name: N2O_rep2
Units: nanomoles per liter (nmol/L)
Description: <p>Concentration of nitrous oxide, second distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858256.rdf
Name: N2O_mean
Units: nanomoles per liter (nmol/L)
Description: <p>Concentration of nitrous oxide, average of replicate samples</p>
http://lod.bco-dmo.org/id/dataset-parameter/858257.rdf
Name: N2O_std
Units: nanomoles per liter (nmol/L)
Description: <p>Concentration of nitrous oxide, standard deviation of replicate samples</p>
http://lod.bco-dmo.org/id/dataset-parameter/858258.rdf
Name: N2O_supersaturation_rep1
Units: nanomoles per liter (nmol/L)
Description: <p>Super-saturation of nitrous oxide, equal to actual nitrous oxide concentration minus saturation concentration, for first replicate concentration measurement</p>
http://lod.bco-dmo.org/id/dataset-parameter/858259.rdf
Name: N2O_supersaturation_rep2
Units: nanomoles per liter (nmol/L)
Description: <p>Super-saturation of nitrous oxide, equal to actual nitrous oxide concentration minus saturation concentration, for second replicate concentration measurement (n=2)</p>
http://lod.bco-dmo.org/id/dataset-parameter/858260.rdf
Name: N2O_supersaturation_mean
Units: nanomoles per liter (nmol/L)
Description: <p>Mean super-saturation of nitrous oxide, equal to actual nitrous oxide concentration minus saturation concentration</p>
http://lod.bco-dmo.org/id/dataset-parameter/858261.rdf
Name: N2O_supersaturation_std
Units: nanomoles per liter (nmol/L)
Description: <p>Standard deviation of super-saturation of nitrous oxide, equal to actual nitrous oxide concentration minus saturation concentration</p>
http://lod.bco-dmo.org/id/dataset-parameter/858262.rdf
Name: d18O_N2O_rep1
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrous oxide, first distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858263.rdf
Name: d18O_N2O_rep2
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrous oxide, second distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858264.rdf
Name: d18O_N2O_mean
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrous oxide, average of replicate samples</p>
http://lod.bco-dmo.org/id/dataset-parameter/858265.rdf
Name: d18O_N2O_std
Units: per mil vs. VSMOW
Description: <p>delta18O of nitrous oxide, standard deviation of replicate samples</p>
http://lod.bco-dmo.org/id/dataset-parameter/858266.rdf
Name: d15N_alpha_N2O_rep1
Units: per mil vs. atmospheric N2
Description: <p>delta15N-alpha of nitrous oxide, first distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858267.rdf
Name: d15N_alpha_N2O_rep2
Units: per mil vs. atmospheric N2
Description: <p>delta15N-alpha of nitrous oxide, second distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858268.rdf
Name: d15N_alpha_N2O_mean
Units: per mil vs. atmospheric N2
Description: <p>delta15N-alpha of nitrous oxide, average of replicates</p>
http://lod.bco-dmo.org/id/dataset-parameter/858269.rdf
Name: d15N_alpha_N2O_std
Units: per mil vs. atmospheric N2
Description: <p>delta15N-alpha of nitrous oxide, standard deviation of replicates</p>
http://lod.bco-dmo.org/id/dataset-parameter/858270.rdf
Name: d15N_beta_N2O_rep1
Units: per mil vs. atmospheric N2
Description: <p>delta15N-beta of nitrous oxide, first distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858271.rdf
Name: d15N_beta_N2O_rep2
Units: per mil vs. atmospheric N2
Description: <p>delta15N-beta of nitrous oxide, second distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858272.rdf
Name: d15N_beta_N2O_mean
Units: per mil vs. atmospheric N2
Description: <p>delta15N-beta of nitrous oxide, average of replicate samples</p>
http://lod.bco-dmo.org/id/dataset-parameter/858273.rdf
Name: d15N_beta_N2O_std
Units: per mil vs. atmospheric N2
Description: <p>delta15N-beta of nitrous oxide, standard deviation of replicate samples</p>
http://lod.bco-dmo.org/id/dataset-parameter/858274.rdf
Name: d15N_N2Obulk_rep1
Units: per mil vs. atmospheric N2
Description: <p>delta15N-bulk of nitrous oxide, first distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858275.rdf
Name: d15N_N2Obulk_rep2
Units: per mil vs. atmospheric N2
Description: <p>delta15N-bulk of nitrous oxide, second distinct replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858276.rdf
Name: d15N_N2Obulk_mean
Units: per mil vs. atmospheric N2
Description: <p>delta15N-bulk of nitrous oxide, average of replicate samples</p>
http://lod.bco-dmo.org/id/dataset-parameter/858277.rdf
Name: d15N_N2Obulk_std
Units: per mil vs. atmospheric N2
Description: <p>delta15N-bulk of nitrous oxide, standard deviation of replicate samples</p>
http://lod.bco-dmo.org/id/dataset-parameter/858278.rdf
Name: SP_1
Units: per mil vs. atmospheric N2
Description: <p>Site preference of nitrous oxide, first replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858279.rdf
Name: SP_2
Units: per mil vs. atmospheric N2
Description: <p>Site preference of nitrous oxide, second replicate sample</p>
http://lod.bco-dmo.org/id/dataset-parameter/858280.rdf
Name: SP_mean
Units: per mil vs. atmospheric N2
Description: <p>Site preference of nitrous oxide, average of replicates</p>
http://lod.bco-dmo.org/id/dataset-parameter/858281.rdf
Name: SP_std
Units: per mil vs. atmospheric N2
Description: <p>Site preference of nitrous oxide, standard deviation of replicates</p>
http://lod.bco-dmo.org/id/dataset-parameter/858282.rdf
Name: N2O_Flag_1
Units: unitless
Description: <p>Flag for first replicate N2O measurement: no flag=good, 3=questionable, 4=bad</p>
http://lod.bco-dmo.org/id/dataset-parameter/858283.rdf
Name: N2O_Flag_2
Units: unitless
Description: <p>Flag for second replicate N2O measurement: no flag=good, 3=questionable, 4=bad</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
83417
https://darchive.mblwhoilibrary.org/bitstream/1912/27430/1/dataset-832995_n2o-natural-abundance-isotopomers__v1.tsv
download
https://doi.org/10.26008/1912/bco-dmo.832995.1
download
onLine
dataset
<p>Seawater samples for dissolved nitrate, nitrite, and nitrous oxide isotope analysis were collected from either a 30-liter, 12-bottle rosette or a 12-liter, 24-bottle rosette. Samples for nitrate and nitrite isotopic analysis were collected, unfiltered, into 500 mL Nalgene polypropylene bottles following three rinses of the bottle, caps, and threads of at least 10% of the bottle volume. After collection from the rosette, samples for nitrate isotopic analysis were syringe-filtered with a 60 mL syringe through a 0.22 µM pore size Sterivex filter into 60-mL high density polyethylene bottles, then frozen at –20ºC</p>
<p>For<strong> nitrite isotopic analysis</strong>, samples were preserved within two hours of collection for δ<sup>15</sup>N-NO<sub>2</sub><sup>-</sup> and δ<sup>18</sup>O-NO<sub>2</sub><sup>-</sup> using the azide method (McIlvin and Altabet, 2005), along with nitrite isotope reference materials (Casciotti et al., 2007) in different amounts. Briefly, seawater samples were added to 20 mL vials in volumes targeted to achieve 10 nmol nitrite, based on shipboard colorimetric nitrite analysis (Grasshoff et al., 1999), then capped with a gray butyl septum (National Scientific) and sealed with an aluminum crimp seal. Where [NO<sub>2</sub><sup>–</sup>] &gt; 0.25 µM (limit of detection for these analyses, Figure S1 in Kelly et al, 2020) but &lt; 2 µM, the maximum volume allowable for analysis (10 mL) seawater was subsampled, regardless of actual nitrite concentration. Reference materials (Table S1, Kelly et al., 2020) were diluted into nitrite-free seawater and prepared in 5 nmol and 10 nmol amounts to bracket low-nitrite samples. Vials were purged with N<sub>2</sub> gas for 15 minutes to remove background N<sub>2</sub>O, then treated with a sparged sodium azide/acetic acid solution to chemically convert dissolved nitrite into N<sub>2</sub>O. The reaction was halted after 30 minutes with the addition of 6 M sodium hydroxide solution (McIlvin and Altabet, 2005).</p>
<p>For <strong>nitrous oxide isotopic analysis</strong>, samples were collected into 160 mL glass serum bottles (Wheaton), following standard gas-sampling procedures: gas-tight tubing (Tygon) was used to overflow each serum bottle with sample three times, after which a ~1 mL air headspace was introduced, and the bottle was capped with a gray butyl septum (National Scientific). Given the trace amount of N<sub>2</sub>O in the atmosphere (NOAA Global Monitoring Laboratory) and complete flushing of the bottle during analysis, the effect of this headspace and N<sub>2</sub>O partitioning between the gas and liquid phase falls within the analytical uncertainty for N<sub>2</sub>O concentration measurements. Samples for N<sub>2</sub>O isotopic analysis were promptly preserved by adding 100 µL mercuric chloride (HgCl<sub>2</sub>) to each 160 mL bottle, then sealed with an aluminum crimp seal and stored at lab temperature (20-22ºC).</p>
<p>&nbsp;</p>
Specified by the Principal Investigator(s)
<p><strong>Sample processing:</strong><br />
Preserved samples were analyzed for nitrate, nitrite, and nitrous oxide isotopes via mass spectrometry using a Thermo Finnigan DELTA V in continuous flow mode. For nitrate isotopic analysis, filtered and frozen samples were analyzed for NOx concentration with a discrete analyzer system (Westco), which uses a cadmium column to convert NO<sub>3</sub><sup>-</sup>&nbsp;to NO<sub>2</sub><sup>-</sup>&nbsp;and colorimetric methods to quantify the concentration of NO<sub>2</sub><sup>-</sup>.&nbsp;&nbsp;Following nitrate concentration analysis, filtered and frozen samples were prepared for nitrate isotopic analysis using the denitrifier method (Sigman et al., 2001; Casciotti et al., 2002), with updates from McIlvin and Casciotti (2011). Samples with any detectable nitrite ([NO<sub>2</sub><sup>-</sup>] &lt; 0.076 µM) were treated with sulfamic acid to convert the nitrite present to sulfuric acid + N<sub>2</sub>&nbsp;gas (Granger and Sigman, 2009), then prepared similarly with the denitrifier method. Three reference materials with a range of δ<sup>15</sup>N and δ<sup>18</sup>O values as well as a process blank were prepared alongside each run of samples (USGS 32, USGS 34, and USGS 35; Table S1 from Kelly et al., 2020). USGS reference materials were also treated with sulfamic acid for sulfamic-treated sample runs.</p>
<p>Samples prepared with the denitrifier method were analyzed via a purge-and-trap system coupled to a Thermo Finnigan DELTA V isotope ratio mass spectrometer in continuous flow (McIlvin and Casciotti, 2011). Likewise, samples preserved shipboard with the azide method (McIlvin and Altabet, 2005) were analyzed for the δ<sup>15</sup>N and δ<sup>18</sup>O of nitrite on the same IRMS system, following the injection of 100 uL antifoam emulsion (Sigma-Aldrich) into each vial. Samples with nitrate &lt; 0.1 µM or nitrite &lt; 0.25 µM were excluded from the nitrate or nitrite δ<sup>15</sup>N and δ<sup>18</sup>O datasets, respectively, due to the large error associated with these low concentrations.&nbsp;</p>
<p>For nitrous oxide isotope analysis, each 160 mL bottle was analyzed on a custom-built purge-and-trap system coupled to a Finnigan DELTA V isotope ratio mass spectrometer (McIlvin and Casciotti, 2010) against a tank of pure N<sub>2</sub>O calibrated by S. Toyoda (Tokyo Tech). Molecular masses 44, 45, and 46 were measured for sample and reference gases, as well as fragment ion masses 30 and 31. These values, along with a set of coefficients to account for “scrambling” at the ion source, were used to solve for the δ<sup>15</sup>N<sub>2</sub>O, δ<sup>15</sup>N<sub>2</sub>O<sup>β</sup>, and δ<sup>18</sup>O-N<sub>2</sub>O of each sample. See Kelly et al. (2020) for a full description of the scrambling calculation. N<sub>2</sub>O concentrations were obtained from the N<sub>2</sub>O peak area, known instrument sensitivity (conversion of mass 44 peak area to nmols N<sub>2</sub>O), and sample weights pre- and post-analysis (McIlvin and Casciotti, 2010).</p>
<p><strong>Data processing:</strong><br />
Samples prepared via the denitrifier method were corrected for drift and any offset/blank as described in McIlvin and Casciotti (2011). For samples prepared for nitrite isotopic analysis via the azide method, first, a correction was applied to account for instrument drift over the course of the run, using the run numbers and raw, measured δ<sup>15</sup>N and δ<sup>18</sup>O of the high-concentration reference materials. Subsequently, a size correction was calculated from two different sizes of standard curves (5 nmol and 10 nmol) and their respective slopes and intercepts; Finally, a size-corrected standard curve was used to calculate the actual isotope ratios from the drift-corrected values.</p>
<p>The isotope ratios of N<sub>2</sub>O and that of the fragment ion NO — namely, 45/44, 46/44, and 31/30 — were first corrected via comparison to direct injections of a common N<sub>2</sub>O reference gas. Following this correction, a linearity relation was applied to these isotope ratios, in order to correct for variations in measured isotope ratios due to peak size. To obtain from these three isotope ratios the individual isotopomers of N<sub>2</sub>O, it was necessary to correct for “scrambling” at the ion source, or the phenomenon by which the NO fragment ion actually contains the outer, beta N atom from the linear N<sub>2</sub>O molecule, instead of the inner, alpha N atom (Toyoda and Yoshida, 1999). Finally, a two-point scale decompression (Mohn et al., 2014) was applied to correct for a consistent offset between measured and inter-calibrated standard values. See Kelly et al. (2020) for a full discussion of the N<sub>2</sub>O isotopomer data corrections.</p>
<p><strong>Problem Report:</strong><br />
Issues were occasionally encountered during analysis of nitrous oxide stable isotopes (clogged lines, etc.). Samples for which issues occurred are flagged in the data accordingly: no flag=good, 3=questionable, 4=bad.</p>
<p><strong>BCO-DMO processing:&nbsp;</strong><br />
- Timestamp data from all cruises were joined to isotopomer dataset<br />
- Timestamp converted to ISO DateTime UTC format in additional column<br />
- Parameter names adjusted to comply with database requirements<br />
- Added a conventional header with dataset name, PI name, version date<br />
- Units added to parameter description metadata section<br />
- Missing data identifier of 'nd' (no data) used</p>
<div>&nbsp;</div>
<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
Westco discrete analyzer system
Westco discrete analyzer system
PI Supplied Instrument Name: Westco discrete analyzer system PI Supplied Instrument Description:Westco discrete analyzer system uses a cadmium column to convert NO3- to NO2- and colorimetric methods to quantify the concentration of NO2
Instrument Name: Discrete Analyzer Instrument Short Name:Discrete Analyzer Instrument Description: Discrete analyzers utilize discrete reaction wells to mix and develop the colorimetric reaction, allowing for a wide variety of assays to be performed from one sample. These instruments are ideal for drinking water, wastewater, soil testing, environmental and university or research applications where multiple assays and high throughput are required.
Thermo Finnigan DELTA V isotope ratio mass spectrometer
Thermo Finnigan DELTA V isotope ratio mass spectrometer
PI Supplied Instrument Name: Thermo Finnigan DELTA V isotope ratio mass spectrometer 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/
Cruise: SR1805
SR1805
R/V Sally Ride
Community Standard Description
International Council for the Exploration of the Sea
R/V Sally Ride
vessel
SR1805
Bess B. Ward
Princeton University
R/V Sally Ride
Community Standard Description
International Council for the Exploration of the Sea
R/V Sally Ride
vessel