Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions
The oceans absorb about a quarter of the annually produced anthropogenic atmospheric carbon dioxide (CO 2 ), resulting in a decrease in surface water pH, a process termed ocean acidification (OA). Surprisingly little is known about how OA affects the physiology of heterotrophic bacteria or the coupl...
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ftunivtasecite:oai:ecite.utas.edu.au:133658 2023-05-15T17:50:58+02:00 Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions Hornick, T Bach, LT Crawfurd, KJ Spilling, K Achterberg, EP Woodhouse, JN Schulz, KG Broussaard, CPD Riebesell, U Grossart, H-P 2017 application/pdf https://doi.org/10.5194/bg-14-1-2017 http://ecite.utas.edu.au/133658 en eng Copernicus GmbH http://ecite.utas.edu.au/133658/1/133658 - Ocean acidification impacts bacteria - phytoplankton coupling.pdf http://dx.doi.org/10.5194/bg-14-1-2017 Hornick, T and Bach, LT and Crawfurd, KJ and Spilling, K and Achterberg, EP and Woodhouse, JN and Schulz, KG and Broussaard, CPD and Riebesell, U and Grossart, H-P, Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions, Biogeosciences, 14 pp. 1-15. ISSN 1726-4170 (2017) [Refereed Article] http://ecite.utas.edu.au/133658 Earth Sciences Oceanography Biological Oceanography Refereed Article PeerReviewed 2017 ftunivtasecite https://doi.org/10.5194/bg-14-1-2017 2019-12-13T22:31:25Z The oceans absorb about a quarter of the annually produced anthropogenic atmospheric carbon dioxide (CO 2 ), resulting in a decrease in surface water pH, a process termed ocean acidification (OA). Surprisingly little is known about how OA affects the physiology of heterotrophic bacteria or the coupling of heterotrophic bacteria to phytoplankton when nutrients are limited. Previous experiments were, for the most part, undertaken during productive phases or following nutrient additions designed to stimulate algal blooms. Therefore, we performed an in situ large-volume mesocosm ( ∼ 55 m 3 ) experiment in the Baltic Sea by simulating different fugacities of CO 2 ( f CO 2 ) extending from present to future conditions. The study was conducted in JulyAugust after the nominal spring bloom, in order to maintain low-nutrient conditions throughout the experiment. This resulted in phytoplankton communities dominated by small-sized functional groups (picophytoplankton). There was no consistent f CO 2 -induced effect on bacterial protein production (BPP), cell-specific BPP (csBPP) or biovolumes (BVs) of either free-living (FL) or particle-associated (PA) heterotrophic bacteria, when considered as individual components (univariate analyses). Permutational Multivariate Analysis of Variance (PERMANOVA) revealed a significant effect of the f CO 2 treatment on entire assemblages of dissolved and particulate nutrients, metabolic parameters and the bacteriaphytoplankton community. However, distance-based linear modelling only identified f CO 2 as a factor explaining the variability observed amongst the microbial community composition, but not for explaining variability within the metabolic parameters. This suggests that f CO 2 impacts on microbial metabolic parameters occurred indirectly through varying physicochemical parameters and microbial species composition. Cluster analyses examining the co-occurrence of different functional groups of bacteria and phytoplankton further revealed a separation of the four f CO 2 -treated mesocosms from both control mesocosms, indicating that complex trophic interactions might be altered in a future acidified ocean. Possible consequences for nutrient cycling and carbon export are still largely unknown, in particular in a nutrient-limited ocean. Article in Journal/Newspaper Ocean acidification eCite UTAS (University of Tasmania) Biogeosciences 14 1 1 15 |
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eCite UTAS (University of Tasmania) |
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English |
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Earth Sciences Oceanography Biological Oceanography |
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Earth Sciences Oceanography Biological Oceanography Hornick, T Bach, LT Crawfurd, KJ Spilling, K Achterberg, EP Woodhouse, JN Schulz, KG Broussaard, CPD Riebesell, U Grossart, H-P Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions |
topic_facet |
Earth Sciences Oceanography Biological Oceanography |
description |
The oceans absorb about a quarter of the annually produced anthropogenic atmospheric carbon dioxide (CO 2 ), resulting in a decrease in surface water pH, a process termed ocean acidification (OA). Surprisingly little is known about how OA affects the physiology of heterotrophic bacteria or the coupling of heterotrophic bacteria to phytoplankton when nutrients are limited. Previous experiments were, for the most part, undertaken during productive phases or following nutrient additions designed to stimulate algal blooms. Therefore, we performed an in situ large-volume mesocosm ( ∼ 55 m 3 ) experiment in the Baltic Sea by simulating different fugacities of CO 2 ( f CO 2 ) extending from present to future conditions. The study was conducted in JulyAugust after the nominal spring bloom, in order to maintain low-nutrient conditions throughout the experiment. This resulted in phytoplankton communities dominated by small-sized functional groups (picophytoplankton). There was no consistent f CO 2 -induced effect on bacterial protein production (BPP), cell-specific BPP (csBPP) or biovolumes (BVs) of either free-living (FL) or particle-associated (PA) heterotrophic bacteria, when considered as individual components (univariate analyses). Permutational Multivariate Analysis of Variance (PERMANOVA) revealed a significant effect of the f CO 2 treatment on entire assemblages of dissolved and particulate nutrients, metabolic parameters and the bacteriaphytoplankton community. However, distance-based linear modelling only identified f CO 2 as a factor explaining the variability observed amongst the microbial community composition, but not for explaining variability within the metabolic parameters. This suggests that f CO 2 impacts on microbial metabolic parameters occurred indirectly through varying physicochemical parameters and microbial species composition. Cluster analyses examining the co-occurrence of different functional groups of bacteria and phytoplankton further revealed a separation of the four f CO 2 -treated mesocosms from both control mesocosms, indicating that complex trophic interactions might be altered in a future acidified ocean. Possible consequences for nutrient cycling and carbon export are still largely unknown, in particular in a nutrient-limited ocean. |
format |
Article in Journal/Newspaper |
author |
Hornick, T Bach, LT Crawfurd, KJ Spilling, K Achterberg, EP Woodhouse, JN Schulz, KG Broussaard, CPD Riebesell, U Grossart, H-P |
author_facet |
Hornick, T Bach, LT Crawfurd, KJ Spilling, K Achterberg, EP Woodhouse, JN Schulz, KG Broussaard, CPD Riebesell, U Grossart, H-P |
author_sort |
Hornick, T |
title |
Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions |
title_short |
Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions |
title_full |
Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions |
title_fullStr |
Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions |
title_full_unstemmed |
Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions |
title_sort |
ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions |
publisher |
Copernicus GmbH |
publishDate |
2017 |
url |
https://doi.org/10.5194/bg-14-1-2017 http://ecite.utas.edu.au/133658 |
genre |
Ocean acidification |
genre_facet |
Ocean acidification |
op_relation |
http://ecite.utas.edu.au/133658/1/133658 - Ocean acidification impacts bacteria - phytoplankton coupling.pdf http://dx.doi.org/10.5194/bg-14-1-2017 Hornick, T and Bach, LT and Crawfurd, KJ and Spilling, K and Achterberg, EP and Woodhouse, JN and Schulz, KG and Broussaard, CPD and Riebesell, U and Grossart, H-P, Ocean acidification impacts bacteria-phytoplankton coupling at low-nutrient conditions, Biogeosciences, 14 pp. 1-15. ISSN 1726-4170 (2017) [Refereed Article] http://ecite.utas.edu.au/133658 |
op_doi |
https://doi.org/10.5194/bg-14-1-2017 |
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Biogeosciences |
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14 |
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1 |
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1 |
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15 |
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1766157930487349248 |