Technical Note: Precise quantitative measurements of total dissolved inorganic carbon from small amounts of seawater using a gas chromatographic system.

Hansen, Thomas, Gardeler, Bente and Matthiessen, Birte (2013) Technical Note: Precise quantitative measurements of total dissolved inorganic carbon from small amounts of seawater using a gas chromatographic system. Open Access Biogeosciences (BG), 10 (10). pp. 6601-6608. DOI 10.5194/bg-10-6601-2013.

[img]
Preview
Text
bg-10-6601-2013.pdf - Published Version
Available under License Creative Commons Attribution.

Download (140Kb) | Preview

Supplementary data:

Abstract

Total dissolved inorganic carbon (CT) is one of the most frequently measured parameters used to calculate the partial pressure of carbon dioxide in seawater. Its determination has become increasingly important because of the rising interest in the biological effects of ocean acidification. Coulometric and infrared detection methods are currently favored in order to precisely quantify CT. These methods however are not sufficiently validated for CT measurements of biological experiments manipulating seawater carbonate chemistry with an extended CT measurement range (~1250–2400 μmol kg–1) compared to natural open ocean seawater (~1950–2200 μmol kg−1). The requirement of total sample amounts between 0.1–1 L seawater in the coulometric- and infrared detection methods potentially exclude their use for experiments working with much smaller volumes. Additionally, precise CT analytics become difficult with high amounts of biomass (e.g., phytoplankton cultures) or even impossible in the presence of planktonic calcifiers without sample pre-filtration. Filtration however, can alter CT concentration through gas exchange induced by high pressure. Addressing these problems, we present precise quantification of CT using a small, basic and inexpensive gas chromatograph as a CT analyzer. Our technique is able to provide a repeatability of ±3.1 μmol kg−1, given by the pooled standard deviation over a CT range typically applied in acidification experiments. 200 μL of sample is required to perform the actual CT measurement. The total sample amount needed is 12 mL. Moreover, we show that sample filtration is applicable with only minor alteration of the CT. The method is simple, reliable and with low cumulative material costs. Hence, it is potentially attractive for all researchers experimentally manipulating the seawater carbonate system.

Document Type: Article
Additional Information: WOS:000326470500027
Keywords: ocean acidification
Research affiliation: OceanRep > GEOMAR > FB3 Marine Ecology > FB3-EOE-N Experimental Ecology - Food Webs
OceanRep > The Future Ocean - Cluster of Excellence
Refereed: Yes
Open Access Journal?: Yes
DOI etc.: 10.5194/bg-10-6601-2013
ISSN: 1726-4170
Projects: Future Ocean
Date Deposited: 11 Dec 2013 09:30
Last Modified: 23 May 2019 08:26
URI: http://oceanrep.geomar.de/id/eprint/22622

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...