Dataset: Porewater Nitrate and Isotopic Ratios

Name: Porewater measurements of nitrate concentration and N and O isotopic ratios (d15N and d18O) from bore holes at North Pond; collected during IODP expedition 336 on R/V JOIDES Resolution in the Mid-Atlantic Ridge in 2011
Published: 2016-02-04
Keywords: oceans

Cite This Dataset

Spatial Extent: N:22.81 E:46.09 S:22.76 W:46.05

Project:

IODP Expedition 336- Mid-Atlantic Ridge Microbiology (Mid-Atl Ridge Microbio)

Program:

Center for Dark Energy Biosphere Investigations (C-DEBI)

Principal Investigator:

Scott Wankel (Woods Hole Oceanographic Institution, WHOI)

Co-Principal Investigator:

Dr Moritz Lehmann (University of Basel (Universitat Basel))

Wiebke Ziebis (University of Southern California, USC)

Contact:

Carolyn Buchwald (Woods Hole Oceanographic Institution, WHOI)

Scott Wankel (Woods Hole Oceanographic Institution, WHOI)

BCO-DMO Data Manager:

Shannon Rauch (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Version:

04 Feb 2016

Version Date:

2016-02-04

Validated:

Current State:

Preliminary and in progress

Porewater measurements of nitrate concentration and N and O isotopic ratios (d15N and d18O) from bore holes at North Pond; collected during IODP expedition 336 on R/V JOIDES Resolution in the Mid-Atlantic Ridge in 2011

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Description

Dataset includes porewater measurements of nitrate concentration and N and O isotopic ratios (d15N and d18O) from bore holes U1382B, U1383D, and U1384A at North Pond during IODP 336.

Methods & Sampling

Sediment cores were collected using an advanced piston corer. Porewaters were extracted by Rhizon samplers either immediately shipboard or later on 10cm whole core rounds that were stored at -80 degrees C.

Nitrate from shipboard extracted samples were measured using ion chromatography, where samples collected later were measured using chemiluminescence after reduction in hot acidic vanadyl sulfate solution on a NOx analyzer (Braman and Hendrix, 1989) (detection limit <0.5 uM). Nitrite was measured using the Griess-Ilosvay method followed by measuring absorption at 540 nm or by chemiluminescence in a sodium iodide solution on a NOx analyzer.

Stable isotopes of nitrate were measured using the denitrifier method (Casciotti et al., 2002; Sigman et al., 2001). Where detected, nitrite was removed by sulfamic acid addition (Granger and Sigman, 2009) prior to isotopic analysis of the nitrate. Samples were run on either a Delta V Advantage (Thermo, Inc.) at the University of Basel or an IsoPrime100 (Elementar, Inc.)

Data Processing Description

For the stable isotope measurements, corrections for drift, size and fractionation of isotopes during the denitrifier method were carried out using nitrate standards USGS 32, USGS 34, and USGS 35 (Casciotti et al., 2002; McIlvin and Casciotti, 2011), with a typical reproducibility of 0.2 and 0.4 ‰ for δ15N and δ18O, respectively.

BCO-DMO Processing:
- modified parameter names to conform with BCO-DMO naming conventions;
- added cruise ID;
- replaced blanks (missing data) with "nd", meaning "no data".

Data Files

File
NPNitrateNO.csv (Comma Separated Values (.csv), 7.27 KB) MD5:da4c28eb568d87f1946a6ee6e7616242 Primary data file for dataset ID 637919

More Information about this dataset

Funding Sources

Funding Source	Award Number
NSF Division of Ocean Sciences	OCE-1131671
NSF Division of Ocean Sciences	OCE-0939564

Deployments

Deployment	Synonyms	Start Date	Platform	Investigator
JRES-336	IODP 336 North Pond	2011-09-16	R/V JOIDES Resolution		data info

Instruments

Advanced Piston Corer

Supplied Description:

Sediment cores were collected using an advanced piston corer.

Instrument Type

Generic Name: Advanced Piston Corer

Acronym: APC

Generic Description:

The JOIDES Resolution's Advanced Piston Corer (APC) is used in soft ooze and sediments. The APC is a hydraulically actuated piston corer designed to recover relatively undisturbed samples from very soft to firm sediments.

More information is available from IODP (PDF).

Chemiluminescence NOx Analyzer

Supplied Name: NOx analyzer

Supplied Description:

Nitrate from shipboard extracted samples were measured using ion chromatography, where samples collected later were measured using chemiluminescence after reduction in hot acidic vanadyl sulfate solution on a NOx analyzer (Braman and Hendrix, 1989) (detection limit <0.5 uM). Nitrite was measured using the Griess-Ilosvay method followed by measuring absorption at 540nm or by chemiluminescence in a sodium iodide solution on a NOx analyzer.

Instrument Type

Generic Name: Chemiluminescence NOx Analyzer

Generic Description:

The chemiluminescence method for gas analysis of oxides of nitrogen relies on the measurement of light produced by the gas-phase titration of nitric oxide and ozone. A chemiluminescence analyzer can measure the concentration of NO/NO2/NOX.

One example is the Teledyne Model T200: https://www.teledyne-api.com/products/nitrogen-compound-instruments/t200

Ion Chromatograph

Supplied Name: Ion Chromatography

Supplied Description:

Nitrate from shipboard extracted samples were measured using ion chromatography.

Instrument Type

Generic Name: Ion Chromatograph

Generic Description:

Ion chromatography is a form of liquid chromatography that measures concentrations of ionic species by separating them based on their interaction with a resin. Ionic species separate differently depending on species type and size. Ion chromatographs are able to measure concentrations of major anions, such as fluoride, chloride, nitrate, nitrite, and sulfate, as well as major cations such as lithium, sodium, ammonium, potassium, calcium, and magnesium in the parts-per-billion (ppb) range. (from http://serc.carleton.edu/microbelife/research_methods/biogeochemical/ic.html)

Isotope-ratio Mass Spectrometer

Supplied Name: Delta V Advantage or IsoPrime100

Supplied Description:

Samples were run on either a Delta V Advantage (Thermo, Inc.) at the University of Basel or an IsoPrime100 (Elementar, Inc.)

Instrument Type

Generic Name: Isotope-ratio Mass Spectrometer

Acronym: IR Mass Spec; IRMS

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/LAB16/

Generic 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).

Parameters

Date and time formats are described in python strftime() syntax.

Supplied Name	Supplied description	Supplied Units	Standard Name
core	Core identifier.	dimensionless	no_bcodmo_term
lat	Latitude.	decimal degrees	lat
lon	Longitude.	decimal degrees	lon
bottom_water_depth	Bottom water depth.	meters (m)	no_bcodmo_term
cruise_id	Cruise identifier.	dimensionless	cruise_id
sample	Sample identifier.	dimensionless	sample
section	Section identifier.	dimensionless	no_bcodmo_term
depth_mbsf	Depth (top of section mbsf).	meters below sea floor (mbsf)	no_bcodmo_term
nitrate	Nitrate.	?	no_bcodmo_term
nitrite	Nitrite.	?	no_bcodmo_term
d15N_nitrate	d15N-Nitrate.	?	no_bcodmo_term
d18O_nitrate	d18O-Nitrate.	?	no_bcodmo_term

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Database

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Dataset: Porewater Nitrate and Isotopic Ratios