Effect of ocean acidification and elevated fCO2 on trace gas production by a Baltic Sea summer phytoplankton community
The Baltic Sea is a unique environment as the largest body of brackish water in the world. Acidification of the surface oceans due to absorption of anthropogenic CO2 emissions is an additional stressor facing the pelagic community of the already challenging Baltic Sea. To investigate its impact on t...
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Online Access: | https://epubs.scu.edu.au/esm_pubs/2988 https://doi.org/10.5194/bg-13-4595-2016 |
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ftsoutherncu:oai:epubs.scu.edu.au:esm_pubs-4006 2023-05-15T17:52:10+02:00 Effect of ocean acidification and elevated fCO2 on trace gas production by a Baltic Sea summer phytoplankton community Webb, Alison L Leedham-Elvidge, Emma Hughes, Claire Hopkins, Frances E Malin, Gill Bach, Lennart T Schulz, Kai Crawfurd, Kate Brussaard, Corina PD Stuhr, Annegret Riebesell, Ulf Liss, Peter S 2016-01-01T08:00:00Z https://epubs.scu.edu.au/esm_pubs/2988 https://doi.org/10.5194/bg-13-4595-2016 unknown ePublications@SCU School of Environment, Science and Engineering Papers Environmental Sciences article 2016 ftsoutherncu https://doi.org/10.5194/bg-13-4595-2016 2019-08-06T13:10:59Z The Baltic Sea is a unique environment as the largest body of brackish water in the world. Acidification of the surface oceans due to absorption of anthropogenic CO2 emissions is an additional stressor facing the pelagic community of the already challenging Baltic Sea. To investigate its impact on trace gas biogeochemistry, a large-scale mesocosm experiment was performed off Tvärminne Research Station, Finland, in summer 2012. During the second half of the experiment, dimethylsulfide (DMS) concentrations in the highest-fCO2 mesocosms (1075–1333 µatm) were 34 % lower than at ambient CO2 (350 µatm). However, the net production (as measured by concentration change) of seven halocarbons analysed was not significantly affected by even the highest CO2 levels after 5 weeks' exposure. Methyl iodide (CH3I) and diiodomethane (CH2I2) showed 15 and 57 % increases in mean mesocosm concentration (3.8 ± 0.6 increasing to 4.3 ± 0.4 pmol L−1 and 87.4 ± 14.9 increasing to 134.4 ± 24.1 pmol L−1 respectively) during Phase II of the experiment, which were unrelated to CO2 and corresponded to 30 % lower Chl a concentrations compared to Phase I. No other iodocarbons increased or showed a peak, with mean chloroiodomethane (CH2ClI) concentrations measured at 5.3 (±0.9) pmol L−1 and iodoethane (C2H5I) at 0.5 (±0.1) pmol L−1. Of the concentrations of bromoform (CHBr3; mean 88.1 ± 13.2 pmol L−1), dibromomethane (CH2Br2; mean 5.3 ± 0.8 pmol L−1), and dibromochloromethane (CHBr2Cl, mean 3.0 ± 0.5 pmol L−1), only CH2Br2 showed a decrease of 17 % between Phases I and II, with CHBr3 and CHBr2Cl showing similar mean concentrations in both phases. Outside the mesocosms, an upwelling event was responsible for bringing colder, high-CO2, low-pH water to the surface starting on day t16 of the experiment; this variable CO2 system with frequent upwelling events implies that the community of the Baltic Sea is acclimated to regular significant declines in pH caused by up to 800 µatm fCO2. After this upwelling, DMS concentrations declined, but halocarbon concentrations remained similar or increased compared to measurements prior to the change in conditions. Based on our findings, with future acidification of Baltic Sea waters, biogenic halocarbon emissions are likely to remain at similar values to today; however, emissions of biogenic sulfur could significantly decrease in this region. Article in Journal/Newspaper Ocean acidification Southern Cross University: epublications@SCU Biogeosciences 13 15 4595 4613 |
institution |
Open Polar |
collection |
Southern Cross University: epublications@SCU |
op_collection_id |
ftsoutherncu |
language |
unknown |
topic |
Environmental Sciences |
spellingShingle |
Environmental Sciences Webb, Alison L Leedham-Elvidge, Emma Hughes, Claire Hopkins, Frances E Malin, Gill Bach, Lennart T Schulz, Kai Crawfurd, Kate Brussaard, Corina PD Stuhr, Annegret Riebesell, Ulf Liss, Peter S Effect of ocean acidification and elevated fCO2 on trace gas production by a Baltic Sea summer phytoplankton community |
topic_facet |
Environmental Sciences |
description |
The Baltic Sea is a unique environment as the largest body of brackish water in the world. Acidification of the surface oceans due to absorption of anthropogenic CO2 emissions is an additional stressor facing the pelagic community of the already challenging Baltic Sea. To investigate its impact on trace gas biogeochemistry, a large-scale mesocosm experiment was performed off Tvärminne Research Station, Finland, in summer 2012. During the second half of the experiment, dimethylsulfide (DMS) concentrations in the highest-fCO2 mesocosms (1075–1333 µatm) were 34 % lower than at ambient CO2 (350 µatm). However, the net production (as measured by concentration change) of seven halocarbons analysed was not significantly affected by even the highest CO2 levels after 5 weeks' exposure. Methyl iodide (CH3I) and diiodomethane (CH2I2) showed 15 and 57 % increases in mean mesocosm concentration (3.8 ± 0.6 increasing to 4.3 ± 0.4 pmol L−1 and 87.4 ± 14.9 increasing to 134.4 ± 24.1 pmol L−1 respectively) during Phase II of the experiment, which were unrelated to CO2 and corresponded to 30 % lower Chl a concentrations compared to Phase I. No other iodocarbons increased or showed a peak, with mean chloroiodomethane (CH2ClI) concentrations measured at 5.3 (±0.9) pmol L−1 and iodoethane (C2H5I) at 0.5 (±0.1) pmol L−1. Of the concentrations of bromoform (CHBr3; mean 88.1 ± 13.2 pmol L−1), dibromomethane (CH2Br2; mean 5.3 ± 0.8 pmol L−1), and dibromochloromethane (CHBr2Cl, mean 3.0 ± 0.5 pmol L−1), only CH2Br2 showed a decrease of 17 % between Phases I and II, with CHBr3 and CHBr2Cl showing similar mean concentrations in both phases. Outside the mesocosms, an upwelling event was responsible for bringing colder, high-CO2, low-pH water to the surface starting on day t16 of the experiment; this variable CO2 system with frequent upwelling events implies that the community of the Baltic Sea is acclimated to regular significant declines in pH caused by up to 800 µatm fCO2. After this upwelling, DMS concentrations declined, but halocarbon concentrations remained similar or increased compared to measurements prior to the change in conditions. Based on our findings, with future acidification of Baltic Sea waters, biogenic halocarbon emissions are likely to remain at similar values to today; however, emissions of biogenic sulfur could significantly decrease in this region. |
format |
Article in Journal/Newspaper |
author |
Webb, Alison L Leedham-Elvidge, Emma Hughes, Claire Hopkins, Frances E Malin, Gill Bach, Lennart T Schulz, Kai Crawfurd, Kate Brussaard, Corina PD Stuhr, Annegret Riebesell, Ulf Liss, Peter S |
author_facet |
Webb, Alison L Leedham-Elvidge, Emma Hughes, Claire Hopkins, Frances E Malin, Gill Bach, Lennart T Schulz, Kai Crawfurd, Kate Brussaard, Corina PD Stuhr, Annegret Riebesell, Ulf Liss, Peter S |
author_sort |
Webb, Alison L |
title |
Effect of ocean acidification and elevated fCO2 on trace gas production by a Baltic Sea summer phytoplankton community |
title_short |
Effect of ocean acidification and elevated fCO2 on trace gas production by a Baltic Sea summer phytoplankton community |
title_full |
Effect of ocean acidification and elevated fCO2 on trace gas production by a Baltic Sea summer phytoplankton community |
title_fullStr |
Effect of ocean acidification and elevated fCO2 on trace gas production by a Baltic Sea summer phytoplankton community |
title_full_unstemmed |
Effect of ocean acidification and elevated fCO2 on trace gas production by a Baltic Sea summer phytoplankton community |
title_sort |
effect of ocean acidification and elevated fco2 on trace gas production by a baltic sea summer phytoplankton community |
publisher |
ePublications@SCU |
publishDate |
2016 |
url |
https://epubs.scu.edu.au/esm_pubs/2988 https://doi.org/10.5194/bg-13-4595-2016 |
genre |
Ocean acidification |
genre_facet |
Ocean acidification |
op_source |
School of Environment, Science and Engineering Papers |
op_doi |
https://doi.org/10.5194/bg-13-4595-2016 |
container_title |
Biogeosciences |
container_volume |
13 |
container_issue |
15 |
container_start_page |
4595 |
op_container_end_page |
4613 |
_version_ |
1766159525401853952 |