Technical note: Coupling infrared gas analysis and cavity ring down spectroscopy for autonomous, high-temporal-resolution measurements of DIC and <i>δ</i><sup>13</sup>C–DIC

A new approach to autonomously determine concentrations of dissolved inorganic carbon (DIC) and its carbon stable isotope ratio (<i>δ</i><sup>13</sup>C–DIC) at high temporal resolution is presented. The simple method requires no customised design. Instead it uses two commerci...

Full description

Bibliographic Details
Main Authors: M. Call, K. G. Schulz, M. C. Carvalho, I. R. Santos, D. T. Maher
Format: Article
Language:English
Published: Copernicus Publications 2017-03-01
Series:Biogeosciences
Online Access:http://www.biogeosciences.net/14/1305/2017/bg-14-1305-2017.pdf
_version_ 1819067496567668736
author M. Call
K. G. Schulz
M. C. Carvalho
I. R. Santos
D. T. Maher
author_facet M. Call
K. G. Schulz
M. C. Carvalho
I. R. Santos
D. T. Maher
author_sort M. Call
collection DOAJ
description A new approach to autonomously determine concentrations of dissolved inorganic carbon (DIC) and its carbon stable isotope ratio (<i>δ</i><sup>13</sup>C–DIC) at high temporal resolution is presented. The simple method requires no customised design. Instead it uses two commercially available instruments currently used in aquatic carbon research. An inorganic carbon analyser utilising non-dispersive infrared detection (NDIR) is coupled to a Cavity Ring-down Spectrometer (CRDS) to determine DIC and <i>δ</i><sup>13</sup>C–DIC based on the liberated CO<sub>2</sub> from acidified aliquots of water. Using a small sample volume of 2 mL, the precision and accuracy of the new method was comparable to standard isotope ratio mass spectrometry (IRMS) methods. The system achieved a sampling resolution of 16 min, with a DIC precision of ±1.5 to 2 µmol kg<sup>−1</sup> and <i>δ</i><sup>13</sup>C–DIC precision of ±0.14 ‰ for concentrations spanning 1000 to 3600 µmol kg<sup>−1</sup>. Accuracy of 0.1 ± 0.06 ‰ for <i>δ</i><sup>13</sup>C–DIC based on DIC concentrations ranging from 2000 to 2230 µmol kg<sup>−1</sup> was achieved during a laboratory-based algal bloom experiment. The high precision data that can be autonomously obtained by the system should enable complex carbonate system questions to be explored in aquatic sciences using high-temporal-resolution observations.
first_indexed 2024-12-21T16:19:11Z
format Article
id doaj.art-6001dd7cb92644009694bc469a6bb317
institution Directory Open Access Journal
issn 1726-4170
1726-4189
language English
last_indexed 2024-12-21T16:19:11Z
publishDate 2017-03-01
publisher Copernicus Publications
record_format Article
series Biogeosciences
spelling doaj.art-6001dd7cb92644009694bc469a6bb3172022-12-21T18:57:37ZengCopernicus PublicationsBiogeosciences1726-41701726-41892017-03-011451305131310.5194/bg-14-1305-2017Technical note: Coupling infrared gas analysis and cavity ring down spectroscopy for autonomous, high-temporal-resolution measurements of DIC and <i>δ</i><sup>13</sup>C–DICM. Call0K. G. Schulz1M. C. Carvalho2I. R. Santos3D. T. Maher4School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, 2480, AustraliaCentre for Coastal Biogeochemistry, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, 2480, AustraliaCentre for Coastal Biogeochemistry, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, 2480, AustraliaNational Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, Coffs Harbour, NSW, 2450, AustraliaSchool of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, 2480, AustraliaA new approach to autonomously determine concentrations of dissolved inorganic carbon (DIC) and its carbon stable isotope ratio (<i>δ</i><sup>13</sup>C–DIC) at high temporal resolution is presented. The simple method requires no customised design. Instead it uses two commercially available instruments currently used in aquatic carbon research. An inorganic carbon analyser utilising non-dispersive infrared detection (NDIR) is coupled to a Cavity Ring-down Spectrometer (CRDS) to determine DIC and <i>δ</i><sup>13</sup>C–DIC based on the liberated CO<sub>2</sub> from acidified aliquots of water. Using a small sample volume of 2 mL, the precision and accuracy of the new method was comparable to standard isotope ratio mass spectrometry (IRMS) methods. The system achieved a sampling resolution of 16 min, with a DIC precision of ±1.5 to 2 µmol kg<sup>−1</sup> and <i>δ</i><sup>13</sup>C–DIC precision of ±0.14 ‰ for concentrations spanning 1000 to 3600 µmol kg<sup>−1</sup>. Accuracy of 0.1 ± 0.06 ‰ for <i>δ</i><sup>13</sup>C–DIC based on DIC concentrations ranging from 2000 to 2230 µmol kg<sup>−1</sup> was achieved during a laboratory-based algal bloom experiment. The high precision data that can be autonomously obtained by the system should enable complex carbonate system questions to be explored in aquatic sciences using high-temporal-resolution observations.http://www.biogeosciences.net/14/1305/2017/bg-14-1305-2017.pdf
spellingShingle M. Call
K. G. Schulz
M. C. Carvalho
I. R. Santos
D. T. Maher
Technical note: Coupling infrared gas analysis and cavity ring down spectroscopy for autonomous, high-temporal-resolution measurements of DIC and <i>δ</i><sup>13</sup>C–DIC
Biogeosciences
title Technical note: Coupling infrared gas analysis and cavity ring down spectroscopy for autonomous, high-temporal-resolution measurements of DIC and <i>δ</i><sup>13</sup>C–DIC
title_full Technical note: Coupling infrared gas analysis and cavity ring down spectroscopy for autonomous, high-temporal-resolution measurements of DIC and <i>δ</i><sup>13</sup>C–DIC
title_fullStr Technical note: Coupling infrared gas analysis and cavity ring down spectroscopy for autonomous, high-temporal-resolution measurements of DIC and <i>δ</i><sup>13</sup>C–DIC
title_full_unstemmed Technical note: Coupling infrared gas analysis and cavity ring down spectroscopy for autonomous, high-temporal-resolution measurements of DIC and <i>δ</i><sup>13</sup>C–DIC
title_short Technical note: Coupling infrared gas analysis and cavity ring down spectroscopy for autonomous, high-temporal-resolution measurements of DIC and <i>δ</i><sup>13</sup>C–DIC
title_sort technical note coupling infrared gas analysis and cavity ring down spectroscopy for autonomous high temporal resolution measurements of dic and i δ i sup 13 sup c dic
url http://www.biogeosciences.net/14/1305/2017/bg-14-1305-2017.pdf
work_keys_str_mv AT mcall technicalnotecouplinginfraredgasanalysisandcavityringdownspectroscopyforautonomoushightemporalresolutionmeasurementsofdicandidisup13supcdic
AT kgschulz technicalnotecouplinginfraredgasanalysisandcavityringdownspectroscopyforautonomoushightemporalresolutionmeasurementsofdicandidisup13supcdic
AT mccarvalho technicalnotecouplinginfraredgasanalysisandcavityringdownspectroscopyforautonomoushightemporalresolutionmeasurementsofdicandidisup13supcdic
AT irsantos technicalnotecouplinginfraredgasanalysisandcavityringdownspectroscopyforautonomoushightemporalresolutionmeasurementsofdicandidisup13supcdic
AT dtmaher technicalnotecouplinginfraredgasanalysisandcavityringdownspectroscopyforautonomoushightemporalresolutionmeasurementsofdicandidisup13supcdic