Articles | Volume 18, issue 5
https://doi.org/10.5194/bg-18-1619-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-18-1619-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Technical note
| 
09 Mar 2021
Technical note |
| 09 Mar 2021
| 09 Mar 2021
Technical note: CO2 is not like CH4 – limits of and corrections to the headspace method to analyse pCO2 in fresh water
Matthias Koschorreck
CORRESPONDING AUTHOR
Department Lake Research, Helmholtz Centre for Environmental Research – UFZ, Brückstrasse 3a, 39114 Magdeburg, Germany
Yves T. Prairie
Département des Sciences Biologiques, Université du
Québec à Montréal, Montréal, Quebec, Canada
Jihyeon Kim
Département des Sciences Biologiques, Université du
Québec à Montréal, Montréal, Quebec, Canada
Rafael Marcé
Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003 Girona, Spain
University of Girona, Girona, Spain
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We explore, together with stakeholders, whether seasonal forecasting of water quantity, quality, and ecology can help support water management at five case study sites, primarily in Europe. Reliable forecasting, a season in advance, has huge potential to improve decision-making. However, managers were reluctant to use the forecasts operationally. Key barriers were uncertainty and often poor historic performance. The importance of practical hands-on experience was also highlighted.
Cynthia Soued and Yves T. Prairie
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Freshwater reservoirs emit greenhouse gases (GHGs, CO2 and CH4) to the atmosphere; however, the sources underlying these emissions are numerous, and their magnitude is not well known. This study quantifies surface CO2 and CH4 emissions and all their potential sources in a tropical reservoir. Results highlight the changes in GHG sources along the river–reservoir continuum, with internal metabolism being a key component but highly uncertain and challenging to estimate at an ecosystem scale.
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Short summary
The concentration of carbon dioxide (CO2) in water samples is often measured using a gas chromatograph. Depending on the chemical composition of the water, this method can produce wrong results. We quantified the possible error and how it depends on water composition and the analytical procedure. We propose a method to correct wrong results by additionally analysing alkalinity in the samples. We provide an easily usable computer code to perform the correction calculations.
The concentration of carbon dioxide (CO2) in water samples is often measured using a gas...
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