Articles | Volume 10, issue 1
Biogeosciences, 10, 555–566, 2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article 29 Jan 2013
Research article | 29 Jan 2013
Ocean acidification shows negligible impacts on high-latitude bacterial community structure in coastal pelagic mesocosms
A.-S. Roy et al.
M. Sperling, J. Piontek, G. Gerdts, A. Wichels, H. Schunck, A.-S. Roy, J. La Roche, J. Gilbert, J. I. Nissimov, L. Bittner, S. Romac, U. Riebesell, and A. Engel
Biogeosciences, 10, 181–191,
Allanah Joy Paul, Lennart T. Bach, Javier Arístegui, Elisabeth von der Esch, Nauzet Hernández-Hernández, Jonna Piiparinen, Laura Ramajo, Kristian Spilling, and Ulf Riebesell
Preprint under review for BGShort summary
We investigated how different deep water chemistry and biology modulate the response of surface plankton communities to upwelling in the Peruvian coastal zone. Our results show that the most influential drivers were the ratio of inorganic nutrients (NOx : PO43-) and the microbial community present in deep water. These led to unexpected responses in the phytoplankton assemblage that could not be predicted by the amount of inorganic nutrients alone.
Shao-Min Chen, Ulf Riebesell, Kai G. Schulz, Elisabeth von der Esch, Eric P. Achterberg, and Lennart T. Bach
Biogeosciences, 19, 295–312,Short summary
Oxygen minimum zones in the ocean are characterized by enhanced carbon dioxide (CO2) levels and are being further acidified by increasing anthropogenic atmospheric CO2. Here we report CO2 system measurements in a mesocosm study offshore Peru during a rare coastal El Niño event to investigate how CO2 dynamics may respond to ongoing ocean deoxygenation. Our observations show that nitrogen limitation, productivity, and plankton community shift play an important role in driving the CO2 dynamics.
Kai G. Schulz, Eric P. Achterberg, Javier Arístegui, Lennart T. Bach, Isabel Baños, Tim Boxhammer, Dirk Erler, Maricarmen Igarza, Verena Kalter, Andrea Ludwig, Carolin Löscher, Jana Meyer, Judith Meyer, Fabrizio Minutolo, Elisabeth von der Esch, Bess B. Ward, and Ulf Riebesell
Biogeosciences, 18, 4305–4320,Short summary
Upwelling of nutrient-rich deep waters to the surface make eastern boundary upwelling systems hot spots of marine productivity. This leads to subsurface oxygen depletion and the transformation of bioavailable nitrogen into inert N2. Here we quantify nitrogen loss processes following a simulated deep water upwelling. Denitrification was the dominant process, and budget calculations suggest that a significant portion of nitrogen that could be exported to depth is already lost in the surface ocean.
Lennart Thomas Bach, Allanah Joy Paul, Tim Boxhammer, Elisabeth von der Esch, Michelle Graco, Kai Georg Schulz, Eric Achterberg, Paulina Aguayo, Javier Arístegui, Patrizia Ayón, Isabel Baños, Avy Bernales, Anne Sophie Boegeholz, Francisco Chavez, Gabriela Chavez, Shao-Min Chen, Kristin Doering, Alba Filella, Martin Fischer, Patricia Grasse, Mathias Haunost, Jan Hennke, Nauzet Hernández-Hernández, Mark Hopwood, Maricarmen Igarza, Verena Kalter, Leila Kittu, Peter Kohnert, Jesus Ledesma, Christian Lieberum, Silke Lischka, Carolin Löscher, Andrea Ludwig, Ursula Mendoza, Jana Meyer, Judith Meyer, Fabrizio Minutolo, Joaquin Ortiz Cortes, Jonna Piiparinen, Claudia Sforna, Kristian Spilling, Sonia Sanchez, Carsten Spisla, Michael Sswat, Mabel Zavala Moreira, and Ulf Riebesell
Biogeosciences, 17, 4831–4852,Short summary
The eastern boundary upwelling system off Peru is among Earth's most productive ocean ecosystems, but the factors that control its functioning are poorly constrained. Here we used mesocosms, moored ~ 6 km offshore Peru, to investigate how processes in plankton communities drive key biogeochemical processes. We show that nutrient and light co-limitation keep productivity and export at a remarkably constant level while stoichiometry changes strongly with shifts in plankton community structure.
Giulia Faucher, Ulf Riebesell, and Lennart Thomas Bach
Clim. Past, 16, 1007–1025,Short summary
We designed five experiments choosing different coccolithophore species that have been evolutionarily distinct for millions of years. If all species showed the same morphological response to an environmental driver, this could be indicative of a response pattern that is conserved over geological timescales. We found an increase in the percentage of malformed coccoliths under altered CO2, providing evidence that this response could be used as paleo-proxy for episodes of acute CO2 perturbations.
Debany Fonseca-Batista, Xuefeng Li, Virginie Riou, Valérie Michotey, Florian Deman, François Fripiat, Sophie Guasco, Natacha Brion, Nolwenn Lemaitre, Manon Tonnard, Morgane Gallinari, Hélène Planquette, Frédéric Planchon, Géraldine Sarthou, Marc Elskens, Julie LaRoche, Lei Chou, and Frank Dehairs
Biogeosciences, 16, 999–1017,Short summary
Dinitrogen fixation and primary production were investigated using stable isotope incubation experiments along two transects off the Western Iberian Margin in May 2014 close to the end of the phytoplankton spring bloom. We observed substantial N2 fixation activities (up to 1533 µmol N m-2 d-1) associated with a predominance of unicellular cyanobacteria and non-cyanobacterial diazotrophs, which seemed to be promoted by the presence of bloom-derived organic matter and excess phosphorus.
Yong Zhang, Lennart T. Bach, Kai T. Lohbeck, Kai G. Schulz, Luisa Listmann, Regina Klapper, and Ulf Riebesell
Biogeosciences, 15, 3691–3701,Short summary
To compare variations in physiological responses to pCO2 between populations, we measured growth, POC and PIC production rates at a pCO2 range from 120 to 2630 µatm for 17 strains of the coccolithophore Emiliania huxleyi from the Azores, Canary Islands, and Norwegian coast near Bergen. Optimal pCO2 for growth and POC production rates and tolerance to low pH was significantly higher for the Bergen population than the Azores and Canary Islands populations.
Katharine J. Crawfurd, Santiago Alvarez-Fernandez, Kristina D. A. Mojica, Ulf Riebesell, and Corina P. D. Brussaard
Biogeosciences, 14, 3831–3849,Short summary
Carbon dioxide (CO2) is increasing in the atmosphere and oceans. To simulate future conditions we manipulated CO2 concentrations of natural Baltic seawater in 55 m3 bags in situ. We saw increased growth rates and abundances of the smallest-sized eukaryotic phytoplankton and reduced abundances of other phytoplankton with increased CO2. Viral and bacterial abundances were also affected. This would lead to more carbon recycling in the surface water and affect marine food webs and the carbon cycle.
Giulia Faucher, Linn Hoffmann, Lennart T. Bach, Cinzia Bottini, Elisabetta Erba, and Ulf Riebesell
Biogeosciences, 14, 3603–3613,Short summary
The main goal of this study was to understand if, similarly to the fossil record, high quantities of toxic metals induce coccolith dwarfism in coccolithophore species. We investigated, for the first time, the effects of trace metals on coccolithophore species other than E. huxleyi and on coccolith morphology and size. Our data show a species-specific sensitivity to trace metal concentration, allowing the recognition of the most-, intermediate- and least-tolerant taxa to trace metal enrichments.
Silke Lischka, Lennart T. Bach, Kai-Georg Schulz, and Ulf Riebesell
Biogeosciences, 14, 447–466,Short summary
We conducted a large-scale field experiment using 55 m3 floating containers (mesocosms) to investigate consequences of near-future projected CO2 elevations (ocean acidification) on a Baltic Sea plankton community in Storfjärden (Finland). The focus of our study was on single- and multicelled small-sized organisms dwelling in the water column. Our results suggest that increasing CO2 concentrations may change the species composition and promote specific food web interactions.
Enis Hrustić, Risto Lignell, Ulf Riebesell, and Tron Frede Thingstad
Biogeosciences, 14, 379–387,Short summary
Phytoplankton in the ocean's stratified layer are limited by mineral nutrients, normally nitrogen, phosphorus, or iron. It is important to know not only which element is limiting, but also the surplus of the secondary limiting element. We explore here, in temperate mesotrophic waters, a bioassay based on alkaline phosphatase that provides information on both of these.
Thomas Hornick, Lennart T. Bach, Katharine J. Crawfurd, Kristian Spilling, Eric P. Achterberg, Jason N. Woodhouse, Kai G. Schulz, Corina P. D. Brussaard, Ulf Riebesell, and Hans-Peter Grossart
Biogeosciences, 14, 1–15,
Rafael Bermúdez, Monika Winder, Annegret Stuhr, Anna-Karin Almén, Jonna Engström-Öst, and Ulf Riebesell
Biogeosciences, 13, 6625–6635,Short summary
Increasing CO2 is changing seawater chemistry towards a lower pH, which affects marine organisms. We investigate the response of a brackish plankton community to a CO2 gradient in terms of structure and fatty acid composition. The structure was resilient to CO2 and did not diverge between treatments. FA was influenced by community structure, which was driven by silicate and phosphate. This suggests that CO2 effects are dampened in communities already experiencing high natural pCO2 fluctuation.
Anu Vehmaa, Anna-Karin Almén, Andreas Brutemark, Allanah Paul, Ulf Riebesell, Sara Furuhagen, and Jonna Engström-Öst
Biogeosciences, 13, 6171–6182,Short summary
Ocean acidification is challenging phenotypic plasticity of individuals and populations. We studied phenotypic plasticity of the calanoid copepod Acartia bifilosa in the course of a pelagic, large-volume mesocosm study in the Baltic Sea. We found significant negative effects of ocean acidification on adult female copepod size and egg hatching success. Overall, these results indicate that A. bifilosa could be affected by projected near-future CO2 levels.
Kristian Spilling, Kai G. Schulz, Allanah J. Paul, Tim Boxhammer, Eric P. Achterberg, Thomas Hornick, Silke Lischka, Annegret Stuhr, Rafael Bermúdez, Jan Czerny, Kate Crawfurd, Corina P. D. Brussaard, Hans-Peter Grossart, and Ulf Riebesell
Biogeosciences, 13, 6081–6093,Short summary
We performed an experiment in the Baltic Sea in order to investigate the consequences of the increasing CO2 levels on biological processes in the free water mass. There was more accumulation of organic carbon at high CO2 levels. Surprisingly, this was caused by reduced loss processes (respiration and bacterial production) in a high-CO2 environment, and not by increased photosynthetic fixation of CO2. Our carbon budget can be used to better disentangle the effects of ocean acidification.
Kristian Spilling, Allanah J. Paul, Niklas Virkkala, Tom Hastings, Silke Lischka, Annegret Stuhr, Rafael Bermúdez, Jan Czerny, Tim Boxhammer, Kai G. Schulz, Andrea Ludwig, and Ulf Riebesell
Biogeosciences, 13, 4707–4719,Short summary
Anthropogenic carbon dioxide (CO2) emissions are reducing the pH in the world's oceans. We determined the plankton community composition and measured primary production, respiration rates and carbon export during an ocean acidification experiment. Our results suggest that increased CO2 reduced respiration and increased net carbon fixation at high CO2. This did not, however, translate into higher carbon export, and consequently did not work as a negative feedback mechanism for decreasing pH.
Juntian Xu, Lennart T. Bach, Kai G. Schulz, Wenyan Zhao, Kunshan Gao, and Ulf Riebesell
Biogeosciences, 13, 4637–4643,
Alison L. Webb, Emma Leedham-Elvidge, Claire Hughes, Frances E. Hopkins, Gill Malin, Lennart T. Bach, Kai Schulz, Kate Crawfurd, Corina P. D. Brussaard, Annegret Stuhr, Ulf Riebesell, and Peter S. Liss
Biogeosciences, 13, 4595–4613,Short summary
This paper presents concentrations of several trace gases produced by the Baltic Sea phytoplankton community during a mesocosm experiment with five different CO2 levels. Average concentrations of dimethylsulphide were lower in the highest CO2 mesocosms over a 6-week period, corresponding to previous mesocosm experiment results. No dimethylsulfoniopropionate was detected due to a methodological issue. Concentrations of iodine- and bromine-containing halocarbons were unaffected by increasing CO2.
Allanah J. Paul, Eric P. Achterberg, Lennart T. Bach, Tim Boxhammer, Jan Czerny, Mathias Haunost, Kai-Georg Schulz, Annegret Stuhr, and Ulf Riebesell
Biogeosciences, 13, 3901–3913,
Carolin R. Löscher, Hermann W. Bange, Ruth A. Schmitz, Cameron M. Callbeck, Anja Engel, Helena Hauss, Torsten Kanzow, Rainer Kiko, Gaute Lavik, Alexandra Loginova, Frank Melzner, Judith Meyer, Sven C. Neulinger, Markus Pahlow, Ulf Riebesell, Harald Schunck, Sören Thomsen, and Hannes Wagner
Biogeosciences, 13, 3585–3606,Short summary
The ocean loses oxygen due to climate change. Addressing this issue in tropical ocean regions (off Peru and Mauritania), we aimed to understand the effects of oxygen depletion on various aspects of marine biogeochemistry, including primary production and export production, the nitrogen cycle, greenhouse gas production, organic matter fluxes and remineralization, and the role of zooplankton and viruses.
Monika Nausch, Lennart Thomas Bach, Jan Czerny, Josephine Goldstein, Hans-Peter Grossart, Dana Hellemann, Thomas Hornick, Eric Pieter Achterberg, Kai-Georg Schulz, and Ulf Riebesell
Biogeosciences, 13, 3035–3050,Short summary
Studies investigating the effect of increasing CO2 levels on the phosphorus cycle in natural waters are lacking although phosphorus often controls phytoplankton development in aquatic systems. The aim of our study was to analyse effects of elevated CO2 levels on phosphorus pool sizes and uptake. Therefore, we conducted a CO2-manipulation mesocosm experiment in the Storfjärden (western Gulf of Finland, Baltic Sea) in summer 2012. We compared the phosphorus dynamics in different mesocosm treatment
Tim Boxhammer, Lennart T. Bach, Jan Czerny, and Ulf Riebesell
Biogeosciences, 13, 2849–2858,
Anna-Karin Almén, Anu Vehmaa, Andreas Brutemark, Lennart Bach, Silke Lischka, Annegret Stuhr, Sara Furuhagen, Allanah Paul, J. Rafael Bermúdez, Ulf Riebesell, and Jonna Engström-Öst
Biogeosciences, 13, 1037–1048,Short summary
We studied the effects of ocean acidification (OA) on the aquatic crustacean Eurytemora affinis and measured offspring production in relation to pH, chlorophyll, algae, fatty acids, and oxidative stress. No effects on offspring production or pH effects via food were found. E. affinis seems robust against OA on a physiological level and did probably not face acute pH stress in the treatments, as the species naturally face large pH fluctuations.
J. Meyer, C. R. Löscher, S. C. Neulinger, A. F. Reichel, A. Loginova, C. Borchard, R. A. Schmitz, H. Hauss, R. Kiko, and U. Riebesell
Biogeosciences, 13, 781–794,
M. N. Müller, J. Barcelos e Ramos, K. G. Schulz, U. Riebesell, J. Kaźmierczak, F. Gallo, L. Mackinder, Y. Li, P. N. Nesterenko, T. W. Trull, and G. M. Hallegraeff
Biogeosciences, 12, 6493–6501,Short summary
The White Cliffs of Dover date back to the Cretaceous and are made up of microscopic chalky shells which were produced mainly by marine phytoplankton (coccolithophores). This is iconic proof for their success at times of relatively high seawater calcium concentrations and, as shown here, to be linked to their ability to precipitate calcium as chalk. The invention of calcification can thus be considered an evolutionary milestone allowing coccolithophores to thrive at times when others struggled.
A. Singh, S. E. Baer, U. Riebesell, A. C. Martiny, and M. W. Lomas
Biogeosciences, 12, 6389–6403,Short summary
Stoichiometry of macronutrients in the subtropical ocean is important to understand how biogeochemical cycles are coupled. We observed that elemental stoichiometry was much higher in the dissolved organic-matter pools than in the particulate organic matter pools. In addition ratios vary with depth due to changes in growth rates of specific phytoplankton groups, namely cyanobacteria. These data will improve biogeochemical models by placing observational constraints on these ratios.
A. J. Paul, L. T. Bach, K.-G. Schulz, T. Boxhammer, J. Czerny, E. P. Achterberg, D. Hellemann, Y. Trense, M. Nausch, M. Sswat, and U. Riebesell
Biogeosciences, 12, 6181–6203,
J. Meyer and U. Riebesell
Biogeosciences, 12, 1671–1682,
S. A. Krueger-Hadfield, C. Balestreri, J. Schroeder, A. Highfield, P. Helaouët, J. Allum, R. Moate, K. T. Lohbeck, P. I. Miller, U. Riebesell, T. B. H. Reusch, R. E. M. Rickaby, J. Young, G. Hallegraeff, C. Brownlee, and D. C. Schroeder
Biogeosciences, 11, 5215–5234,
M. N. Müller, M. Lebrato, U. Riebesell, J. Barcelos e Ramos, K. G. Schulz, S. Blanco-Ameijeiras, S. Sett, A. Eisenhauer, and H. M. Stoll
Biogeosciences, 11, 1065–1075,
A. Silyakova, R. G. J. Bellerby, K. G. Schulz, J. Czerny, T. Tanaka, G. Nondal, U. Riebesell, A. Engel, T. De Lange, and A. Ludvig
Biogeosciences, 10, 4847–4859,
J. Czerny, K. G. Schulz, T. Boxhammer, R. G. J. Bellerby, J. Büdenbender, A. Engel, S. A. Krug, A. Ludwig, K. Nachtigall, G. Nondal, B. Niehoff, A. Silyakova, and U. Riebesell
Biogeosciences, 10, 3109–3125,
J. Czerny, K. G. Schulz, S. A. Krug, A. Ludwig, and U. Riebesell
Biogeosciences, 10, 1937–1941,
U. Riebesell, J. Czerny, K. von Bröckel, T. Boxhammer, J. Büdenbender, M. Deckelnick, M. Fischer, D. Hoffmann, S. A. Krug, U. Lentz, A. Ludwig, R. Muche, and K. G. Schulz
Biogeosciences, 10, 1835–1847,
N. Aberle, K. G. Schulz, A. Stuhr, A. M. Malzahn, A. Ludwig, and U. Riebesell
Biogeosciences, 10, 1471–1481,
A. Engel, C. Borchard, J. Piontek, K. G. Schulz, U. Riebesell, and R. Bellerby
Biogeosciences, 10, 1291–1308,
A. de Kluijver, K. Soetaert, J. Czerny, K. G. Schulz, T. Boxhammer, U. Riebesell, and J. J. Middelburg
Biogeosciences, 10, 1425–1440,
C. P. D. Brussaard, A. A. M. Noordeloos, H. Witte, M. C. J. Collenteur, K. Schulz, A. Ludwig, and U. Riebesell
Biogeosciences, 10, 719–731,
T. Tanaka, S. Alliouane, R. G. B. Bellerby, J. Czerny, A. de Kluijver, U. Riebesell, K. G. Schulz, A. Silyakova, and J.-P. Gattuso
Biogeosciences, 10, 315–325,
J. Piontek, C. Borchard, M. Sperling, K. G. Schulz, U. Riebesell, and A. Engel
Biogeosciences, 10, 297–314,
K. G. Schulz, R. G. J. Bellerby, C. P. D. Brussaard, J. Büdenbender, J. Czerny, A. Engel, M. Fischer, S. Koch-Klavsen, S. A. Krug, S. Lischka, A. Ludwig, M. Meyerhöfer, G. Nondal, A. Silyakova, A. Stuhr, and U. Riebesell
Biogeosciences, 10, 161–180,
M. Sperling, J. Piontek, G. Gerdts, A. Wichels, H. Schunck, A.-S. Roy, J. La Roche, J. Gilbert, J. I. Nissimov, L. Bittner, S. Romac, U. Riebesell, and A. Engel
Biogeosciences, 10, 181–191,
Related subject area
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Coulson A. Lantz, William Leggat, Jessica L. Bergman, Alexander Fordyce, Charlotte Page, Thomas Mesaglio, and Tracy D. Ainsworth
Biogeosciences, 19, 891–906,Short summary
Coral bleaching events continue to drive the degradation of coral reefs worldwide. In this study we measured rates of daytime coral reef community calcification and photosynthesis during a reef-wide bleaching event. Despite a measured decline in coral health across several taxa, there was no change in overall daytime community calcification and photosynthesis. These findings highlight potential limitations of these community-level metrics to reflect actual changes in coral health.
Hyewon Heather Kim, Jeff S. Bowman, Ya-Wei Luo, Hugh W. Ducklow, Oscar M. Schofield, Deborah K. Steinberg, and Scott C. Doney
Biogeosciences, 19, 117–136,Short summary
Heterotrophic marine bacteria are tiny organisms responsible for taking up organic matter in the ocean. Using a modeling approach, this study shows that characteristics (taxonomy and physiology) of bacteria are associated with a subset of ecological processes in the coastal West Antarctic Peninsula region, a system susceptible to global climate change. This study also suggests that bacteria will become more active, in particular large-sized cells, in response to changing climates in the region.
Alice E. Webb, Didier M. de Bakker, Karline Soetaert, Tamara da Costa, Steven M. A. C. van Heuven, Fleur C. van Duyl, Gert-Jan Reichart, and Lennart J. de Nooijer
Biogeosciences, 18, 6501–6516,Short summary
The biogeochemical behaviour of shallow reef communities is quantified to better understand the impact of habitat degradation and species composition shifts on reef functioning. The reef communities investigated barely support reef functions that are usually ascribed to conventional coral reefs, and the overall biogeochemical behaviour is found to be similar regardless of substrate type. This suggests a decrease in functional diversity which may therefore limit services provided by this reef.
Emmanuel Devred, Andrea Hilborn, and Cornelia Elizabeth den Heyer
Biogeosciences, 18, 6115–6132,Short summary
A theoretical model of grey seal seasonal abundance on Sable Island (SI) coupled with chlorophyll-a concentration [chl-a] measured by satellite revealed the impact of seal nitrogen fertilization on the surrounding waters of SI, Canada. The increase in seals from about 100 000 in 2003 to about 360 000 in 2018 during the breeding season is consistent with an increase in [chl-a] leeward of SI. The increase in seal abundance explains 8 % of the [chl-a] increase.
Julie Meilland, Michael Siccha, Maike Kaffenberger, Jelle Bijma, and Michal Kucera
Biogeosciences, 18, 5789–5809,Short summary
Planktonic foraminifera population dynamics has long been assumed to be controlled by synchronous reproduction and ontogenetic vertical migration (OVM). Due to contradictory observations, this concept became controversial. We here test it in the Atlantic ocean for four species of foraminifera representing the main clades. Our observations support the existence of synchronised reproduction and OVM but show that more than half of the population does not follow the canonical trajectory.
Masaya Yoshikai, Takashi Nakamura, Rempei Suwa, Sahadev Sharma, Rene Rollon, Jun Yasuoka, Ryohei Egawa, and Kazuo Nadaoka
Revised manuscript accepted for BGShort summary
This study presents a new individual-based vegetation model to investigate salinity control on mangrove productivity. The model incorporates plant hydraulics and tree competition and predicted unique and complex patterns of mangrove forest structures that varies across soil salinity gradient. The presented model does not hold an empirical expression of salinity influence on productivity, and thus may provide a better understanding of mangrove forest dynamics in future climate change.
Emanuela Fanelli, Samuele Menicucci, Sara Malavolti, Andrea De Felice, and Iole Leonori
Revised manuscript accepted for BGShort summary
Zooplankton play a key role in marine ecosystems, representing the base of marine food webs and a link between primary producers and higher-order consumers, such as fishes. This aspect is crucial in the Adriatic basin, one of the most productive and overexpoited area of the Mediterranean Sea. Thus, a better understanding of communities' and food web structure, and their response to water masses' changes is essential under a global warming scenario, being zooplankton sensitive to climate change.
Federica Maggioni, Mireille Pujo-Pay, Jérome Aucan, Carlo Cerrano, Barbara Calcinai, Claude Payri, Francesca Benzoni, Yves Letourneur, and Riccardo Rodolfo-Metalpa
Biogeosciences, 18, 5117–5140,Short summary
Based on current experimental evidence, climate change will affect up to 90 % of coral reefs worldwide. The originality of this study arises from our recent discovery of an exceptional study site where environmental conditions (temperature, pH, and oxygen) are even worse than those forecasted for the future. While these conditions are generally recognized as unfavorable for marine life, we found a rich and abundant coral reef thriving under such extreme environmental conditions.
Uri Obolski, Thomas Wichard, Alvaro Israel, Alexander Golberg, and Alexander Liberzon
Revised manuscript accepted for BGShort summary
The algal genus Ulva plays a major role in coastal ecosystems worldwide and is a promising prospect as an seagriculture crop. A substantial hindrance to cultivating Ulva arises from sudden sporulation, leading to biomass loss. This process is not yet well understood. Here, we characterize the dynamics of Ulva growth, considering the potential impact of sporulation inhibitors, using a mathematical model. Our findings are an essential step towards understanding the dynamics of Ulva growth.
Nisan Sariaslan and Martin R. Langer
Biogeosciences, 18, 4073–4090,Short summary
Analyses of foraminiferal assemblages from the Mamanguape mangrove estuary (northern Brazil) revealed highly diverse, species-rich, and structurally complex biotas. The atypical fauna resembles shallow-water offshore assemblages and are interpreted to be the result of highly saline ocean waters penetrating deep into the estuary. The findings contrast with previous studies, have implications for the fossil record, and provide novel perspectives for reconstructing mangrove environments.
Jutta E. Wollenburg, Jelle Bijma, Charlotte Cremer, Ulf Bickmeyer, and Zora Mila Colomba Zittier
Biogeosciences, 18, 3903–3915,Short summary
Cultured at in situ high-pressure conditions Cibicides and Cibicidoides taxa develop lasting ectoplasmic structures that cannot be retracted or resorbed. An ectoplasmic envelope surrounds their test and may protect the shell, e.g. versus carbonate aggressive bottom water conditions. Ectoplasmic roots likely anchor the specimens in areas of strong bottom water currents, trees enable them to elevate themselves above ground, and twigs stabilize and guide the retractable pseudopodial network.
Biogeosciences, 18, 3631–3635,Short summary
The Indian Ocean Rim hosts many of the underdeveloped and emerging economies that depend on ocean resources for the livelihood of millions. Operational ocean information services cater to the requirements of resource managers and end-users to efficiently harness resources, mitigate threats and ensure safety. This paper outlines existing tools and explores the ongoing research that has the potential to convert the findings into operational services in the near- to midterm.
Finn Mielck, Rune Michaelis, H. Christian Hass, Sarah Hertel, Caroline Ganal, and Werner Armonies
Biogeosciences, 18, 3565–3577,Short summary
Marine sand mining is becoming more and more important to nourish fragile coastlines that face global change. We investigated the largest sand extraction site in the German Bight. The study reveals that after more than 35 years of mining, the excavation pits are still detectable on the seafloor while the sediment composition has largely changed. The organic communities living in and on the seafloor were strongly decimated, and no recovery is observable towards previous conditions.
France Van Wambeke, Elvira Pulido, Philippe Catala, Julie Dinasquet, Kahina Djaoudi, Anja Engel, Marc Garel, Sophie Guasco, Barbara Marie, Sandra Nunige, Vincent Taillandier, Birthe Zäncker, and Christian Tamburini
Biogeosciences, 18, 2301–2323,Short summary
Michaelis–Menten kinetics were determined for alkaline phosphatase, aminopeptidase and β-glucosidase in the Mediterranean Sea. Although the ectoenzymatic-hydrolysis contribution to heterotrophic prokaryotic needs was high in terms of N, it was low in terms of C. This study points out the biases in interpretation of the relative differences in activities among the three tested enzymes in regard to the choice of added concentrations of fluorogenic substrates.
Oscar E. Romero, Simon Ramondenc, and Gerhard Fischer
Biogeosciences, 18, 1873–1891,Short summary
Upwelling intensity along NW Africa varies on the interannual to decadal timescale. Understanding its changes is key for the prediction of future changes of CO2 sequestration in the northeastern Atlantic. Based on a multiyear (1988–2009) sediment trap experiment at the site CBmeso, fluxes and the species composition of the diatom assemblage are presented. Our data help in establishing the scientific basis for forecasting and modeling future states of this ecosystem and its decadal changes.
Katharine T. Bigham, Ashley A. Rowden, Daniel Leduc, and David A. Bowden
Biogeosciences, 18, 1893–1908,Short summary
Turbidity flows – underwater avalanches – are large-scale physical disturbances believed to have profound impacts on productivity and diversity of benthic communities in the deep sea. We reviewed published studies and found that current evidence for changes in productivity is ambiguous at best, but the influence on regional and local diversity is clearer. We suggest study design criteria that may lead to a better understanding of large-scale disturbance effects on deep-sea benthos.
Phillip Williamson, Hans-Otto Pörtner, Steve Widdicombe, and Jean-Pierre Gattuso
Biogeosciences, 18, 1787–1792,Short summary
The reliability of ocean acidification research was challenged in early 2020 when a high-profile paper failed to corroborate previously observed impacts of high CO2 on the behaviour of coral reef fish. We now know the reason why: the
replicatedstudies differed in many ways. Open-minded and collaborative assessment of all research results, both negative and positive, remains the best way to develop process-based understanding of the impacts of ocean acidification on marine organisms.
Michael Lintner, Bianca Lintner, Wolfgang Wanek, Nina Keul, and Petra Heinz
Biogeosciences, 18, 1395–1406,Short summary
Foraminifera are unicellular marine organisms that play an important role in the marine element cycle. Changes of environmental parameters such as salinity or temperature have a significant impact on the faunal assemblages. Our experiments show that changes in salinity immediately influence the foraminiferal activity. Also the light regime has a significant impact on carbon or nitrogen processing in foraminifera which contain no kleptoplasts.
Michele Casini, Martin Hansson, Alessandro Orio, and Karin Limburg
Biogeosciences, 18, 1321–1331,Short summary
In the past 20 years the condition of the eastern Baltic cod has dropped, with large implications for the fishery. Our results show that simultaneously the cod population has moved deeper while low-oxygenated waters detrimental for cod growth have become shallower. Cod have thus dwelled more in detrimental waters, explaining the drop in its condition. This study, using long-term fish and hydrological monitoring data, evidences the impact of deoxygenation on fish biology and fishing.
Elizabeth D. LaBone, Kenneth A. Rose, Dubravko Justic, Haosheng Huang, and Lixia Wang
Biogeosciences, 18, 487–507,Short summary
The hypoxic zone is an area of low dissolved oxygen (DO) in the Gulf of Mexico. Fish can be killed by exposure to hypoxia and can be negatively impacted by exposure to low, nonlethal DO concentrations (sublethal DO). We found that high sublethal area resulted in higher exposure and DO variability had a small effect on exposure. There was a large variation in exposure among individuals, which when combined with spatial variability of DO, can result in an underestimation of exposure when averaged.
Svenja Reents, Peter Mueller, Hao Tang, Kai Jensen, and Stefanie Nolte
Biogeosciences, 18, 403–411,Short summary
By conducting a flooding experiment with two genotypes of the salt-marsh grass Elymus athericus, we show considerable differences in biomass response to flooding within the same species. As biomass production plays a major role in sedimentation processes and thereby salt-marsh accretion, we emphasise the importance of taking intraspecific differences into account when evaluating ecosystem resilience to accelerated sea level rise.
Cara Nissen and Meike Vogt
Biogeosciences, 18, 251–283,Short summary
Using a regional Southern Ocean ecosystem model, we find that the relative importance of Phaeocystis and diatoms at high latitudes is controlled by iron and temperature variability, with light levels controlling the seasonal succession in coastal areas. Yet, biomass losses via aggregation and grazing matter as well. We show that the seasonal succession of Phaeocystis and diatoms impacts the seasonality of carbon export fluxes with ramifications for nutrient cycling and food web dynamics.
Jiangtao Li, Lingyuan Gu, Shijie Bai, Jie Wang, Lei Su, Bingbing Wei, Li Zhang, and Jiasong Fang
Biogeosciences, 18, 113–133,Short summary
Few studies have focused on the particle-attached (PA) and free-living (FL) microbes of the deep ocean. Here we determined PA and FL microbial communities along depth profiles of the SCS. PA and FL fractions accommodated divergent microbial compositions, and most of them are potentially generalists with PA and FL dual lifestyles. A potential vertical connectivity between surface-specific microbes and those in the deep ocean was indicated, likely through microbial attachment to sinking particles.
Saskia Brix, Karen J. Osborn, Stefanie Kaiser, Sarit B. Truskey, Sarah M. Schnurr, Nils Brenke, Marina Malyutina, and Pedro Martinez Arbizu
Biogeosciences, 17, 6163–6184,Short summary
The Clarion–Clipperton Fracture Zone (CCZ) located in the Pacific is commercially the most important area of proposed manganese nodule mining. Extraction of this will influence the life and distribution of small deep-sea invertebrates like peracarid crustaceans, of which >90 % are undescribed species new to science. We are doing a species delimitation approach as baseline for an ecological interpretation of species distribution and discuss the results in light of future deep-sea conservation.
Amal Jayakumar and Bess B. Ward
Biogeosciences, 17, 5953–5966,Short summary
Diversity and community composition of nitrogen-fixing microbes in the three main oxygen minimum zones of the world ocean were investigated using nifH clone libraries. Representatives of three main clusters of nifH genes were detected. Sequences were most diverse in the surface waters. The most abundant OTUs were affiliated with Alpha- and Gammaproteobacteria. The sequences were biogeographically distinct and the dominance of a few OTUs was commonly observed in OMZs in this (and other) studies.
Guillermo Feliú, Marc Pagano, Pamela Hidalgo, and François Carlotti
Biogeosciences, 17, 5417–5441,Short summary
The impact of Saharan dust deposition events on the Mediterranean Sea ecosystem was studied during a basin-scale survey (PEACETIME cruise, May–June 2017). Short-term responses of the zooplankton community were observed after episodic dust deposition events, highlighting the impact of these events on productivity up to the zooplankton level in the poorly fertilized pelagic ecosystems of the southern Mediterranean Sea.
Douglas Lessa, Raphaël Morard, Lukas Jonkers, Igor M. Venancio, Runa Reuter, Adrian Baumeister, Ana Luiza Albuquerque, and Michal Kucera
Biogeosciences, 17, 4313–4342,Short summary
We observed that living planktonic foraminifera had distinct vertically distributed communities across the Subtropical South Atlantic. In addition, a hierarchic alternation of environmental parameters was measured to control the distribution of planktonic foraminifer's species depending on the water depth. This implies that not only temperature but also productivity and subsurface processes are signed in fossil assemblages, which could be used to perform paleoceanographic reconstructions.
Karl M. Attard and Ronnie N. Glud
Biogeosciences, 17, 4343–4353,Short summary
Light-use efficiency defines the ability of primary producers to convert sunlight energy to primary production. This report provides a framework to compute hourly and daily light-use efficiency using underwater eddy covariance, a recent technological development that produces habitat-scale rates of primary production for many different habitat types. The approach, tested on measured flux data, provides a useful means to compare habitat productivity across time and space.
Stacy Deppeler, Kai G. Schulz, Alyce Hancock, Penelope Pascoe, John McKinlay, and Andrew Davidson
Biogeosciences, 17, 4153–4171,Short summary
Our study showed how ocean acidification can exert both direct and indirect influences on the interactions among trophic levels within the microbial loop. Microbial grazer abundance was reduced at CO2 concentrations at and above 634 µatm, while microbial communities increased in abundance, likely due to a reduction in being grazed. Such changes in predator–prey interactions with ocean acidification could have significant effects on the food web and biogeochemistry in the Southern Ocean.
Mirjana Najdek, Marino Korlević, Paolo Paliaga, Marsej Markovski, Ingrid Ivančić, Ljiljana Iveša, Igor Felja, and Gerhard J. Herndl
Biogeosciences, 17, 3299–3315,Short summary
The response of Cymodocea nodosa to environmental changes was reported during a 15-month period. The meadow decline was triggered in spring by the simultaneous reduction of available light in the water column and the creation of anoxic conditions in the rooted area. This disturbance was critical for the plant since it took place during its recruitment phase when metabolic needs are maximal and stored reserves minimal. The loss of such habitat-forming seagrass is a major environmental concern.
Timm Schoening, Autun Purser, Daniel Langenkämper, Inken Suck, James Taylor, Daphne Cuvelier, Lidia Lins, Erik Simon-Lledó, Yann Marcon, Daniel O. B. Jones, Tim Nattkemper, Kevin Köser, Martin Zurowietz, Jens Greinert, and Jose Gomes-Pereira
Biogeosciences, 17, 3115–3133,Short summary
Seafloor imaging is widely used in marine science and industry to explore and monitor areas of interest. The selection of the most appropriate imaging gear and deployment strategy depends on the target application. This paper compares imaging platforms like autonomous vehicles or towed camera frames and different deployment strategies of those in assessing the megafauna abundance of polymetallic-nodule fields. The deep-sea mining industry needs that information for robust impact monitoring.
Tatsuro Tanioka and Katsumi Matsumoto
Biogeosciences, 17, 2939–2954,Short summary
We conducted an extensive literature survey (meta-analysis) on how the C : N : P ratio varies with change in key environmental drivers. We found that the expected reduction in nutrients and warming under the future climate change scenario is likely to result in increased C : P and C : N of marine phytoplankton. Further, our findings highlight the greater stoichiometric plasticity of eukaryotes over prokaryotes, which provide us insights on how to understand and model plankton.
Vanessa Joglar, Antero Prieto, Esther Barber-Lluch, Marta Hernández-Ruiz, Emilio Fernández, and Eva Teira
Biogeosciences, 17, 2807–2823,Short summary
Coastal marine ecosystems are among the most ecologically and economically productive areas providing a large fraction of ecosystem goods and services to human populations, and B vitamins have long been considered important growth factors for phytoplankton. Our findings indicate that the responses of microbial plankton to B-vitamin supply are mainly driven by the bacterial community composition and that microbial plankton in this area seems to be well adapted to cope with B-vitamin shortage.
Tasnim Patel, Henri Robert, Cedric D'Udekem D'Acoz, Koen Martens, Ilse De Mesel, Steven Degraer, and Isa Schön
Biogeosciences, 17, 2731–2744,Short summary
Exploitation of deep-sea resources in one of the largest ecosystems on the planet has rendered research of its biodiversity more urgent than ever before. We investigated the known habitats and connectivity of deep-sea scavenging amphipods and obtained important knowledge about several species. We also demonstrated that a long-term disturbance experiment has possibly reduced amphipod biodiversity. These data and further sampling expeditions are instrumental for formulating sustainable policies.
Daphne Cuvelier, Pedro A. Ribeiro, Sofia P. Ramalho, Daniel Kersken, Pedro Martinez Arbizu, and Ana Colaço
Biogeosciences, 17, 2657–2680,Short summary
Polymetallic nodule mining will remove hard substrata from the abyssal deep-sea floor. The only neighbouring ecosystems featuring hard substratum are seamounts, and their inhabiting fauna could aid in recovery post-mining. Nevertheless, first observations of seamount megafauna were very different from nodule-associated megafauna and showed little overlap. The possible uniqueness of these ecosystems implies that they should be included in management plans for the conservation of biodiversity.
Karen F. Wishner, Brad Seibel, and Dawn Outram
Biogeosciences, 17, 2315–2339,Short summary
Increasing deoxygenation and oxygen minimum zone expansion are consequences of global warming. Copepod species had different vertical distribution strategies and physiologies associated with oxygen profile variability (0–1000 m). Species (1) changed vertical distributions and maximum abundance depth, (2) shifted diapause depth, (3) changed diel vertical migration depths, or (4) changed epipelagic depth range in the aerobic mixed layer. Present-day variability helps predict future scenarios.
Magdalini Christodoulou, Timothy O'Hara, Andrew F. Hugall, Sahar Khodami, Clara F. Rodrigues, Ana Hilario, Annemiek Vink, and Pedro Martinez Arbizu
Biogeosciences, 17, 1845–1876,Short summary
Unexpectedly high diversity was revealed in areas licenced for polymetallic nodule mining exploration in the Pacific Ocean. For the first time, a comprehensive reference library including 287 novel ophiuroid sequences allocated to 43 species was produced. Differences in food availability along the nodule province of CCZ were reflected in the biodiversity patterns observed. The APEI3's dissimilarity with the exploration contract areas questions its ability to serve as a biodiversity reservoir.
Julie Meilland, Hélène Howa, Vivien Hulot, Isaline Demangel, Joëlle Salaün, and Thierry Garlan
Biogeosciences, 17, 1437–1450,Short summary
This study reports on planktonic foraminifera (PF) diversity and distribution in the Barents Sea. The species Globigerinita uvula and Turborotalita quinqueloba dominate the water column while surface sediments are dominated by Neogloboquadrina pachyderma. We hypothesize the unusual dominance of G. uvula in the water to be a seasonal signal or a result of climate forcing. Size-normalized-protein concentrations of PF show a northward decrease, suggesting biomass to vary with the environment.
Julien Richirt, Bettina Riedel, Aurélia Mouret, Magali Schweizer, Dewi Langlet, Dorina Seitaj, Filip J. R. Meysman, Caroline P. Slomp, and Frans J. Jorissen
Biogeosciences, 17, 1415–1435,Short summary
The paper presents the response of benthic foraminiferal communities to seasonal absence of oxygen coupled with the presence of hydrogen sulfide, considered very harmful for several living organisms. Our results suggest that the foraminiferal community mainly responds as a function of the duration of the adverse conditions. This knowledge is especially useful to better understand the ecology of benthic foraminifera but also in the context of palaeoceanographic interpretations.
Xiangqi Yi, Fei-Xue Fu, David A. Hutchins, and Kunshan Gao
Biogeosciences, 17, 1169–1180,Short summary
Combined effects of warming and light intensity were estimated in N2-fixing cyanobacterium Trichodesmium. Its physiological responses to warming were significantly modulated by light, with growth peaking at 27 °C under the light-saturating condition but being non-responsive across the range of 23–31 °C under the light-limiting condition. Light shortage also weakened the acclimation ability of Trichodesmium to warming, making light-limited Trichodesmium more sensitive to acute temperature change.
Jan Goleń, Jarosław Tyszka, Ulf Bickmeyer, and Jelle Bijma
Biogeosciences, 17, 995–1011,Short summary
We studied the organisation and dynamics of actin in foraminifera. Actin is one of the key structural proteins in most lifeforms. Our investigations show that in foraminifera it forms small granules, around 1 µm in diameter, that display rapid movement. This granularity is unusual in comparison to other organisms. We suppose that these granules are most likely involved in the formation of all types of pseudopods responsible for movement, food capturing, biomineralisation, and other functions.
Paulo Bonifácio, Pedro Martínez Arbizu, and Lénaïck Menot
Biogeosciences, 17, 865–886,Short summary
The patterns observed in the composition of polychaete assemblages were attributed to variations in food supply at the regional scale and nodule density at the local scale. The high levels of species replacement were mainly driven by rare species, leading to regional species pool estimates between 498 and 240 000 species. The high proportion of singletons seems reflect an under-sampling bias that is currently preventing the assessment of potential biodiversity loss due to nodule mining.
Stephanie Dutkiewicz, Pedro Cermeno, Oliver Jahn, Michael J. Follows, Anna E. Hickman, Darcy A. A. Taniguchi, and Ben A. Ward
Biogeosciences, 17, 609–634,Short summary
Phytoplankton are an essential component of the marine food web and earth's carbon cycle. We use observations, ecological theory and a unique trait-based ecosystem model to explain controls on patterns of marine phytoplankton biodiversity. We find that different dimensions of diversity (size classes, biogeochemical functional groups, thermal norms) are controlled by a disparate combination of mechanisms. This may explain why previous studies of phytoplankton diversity had conflicting results.
Emily White, Clara J. M. Hoppe, and Björn Rost
Biogeosciences, 17, 635–647,Short summary
The Arctic picoeukaryote Micromonas pusilla was acclimated to two pCO2 levels under a constant and a dynamic light, simulating more realistic light fields. M. pusilla was able to benefit from ocean acidification with an increase in growth rate, irrespective of the light regime. In dynamic light M. pusilla optimised its photophysiology for effective light usage during both low- and high-light periods. This highlights M. pusilla is likely to cope well with future conditions in the Arctic Ocean.
Oscar E. Romero, Karl-Heinz Baumann, Karin A. F. Zonneveld, Barbara Donner, Jens Hefter, Bambaye Hamady, Vera Pospelova, and Gerhard Fischer
Biogeosciences, 17, 187–214,Short summary
Monitoring of the multiannual evolution of populations representing different trophic levels allows for obtaining insights into the impact of climate variability in marine coastal upwelling ecosystems. By using a multiyear, continuous (1,900 d) sediment trap record, we assess the dynamics and fluxes of calcareous, organic and siliceous microorganisms off Mauritania (NW Africa). The experiment allowed for the recognition of a general sequence of seasonal variations of the main populations.
Ulrike Hanz, Claudia Wienberg, Dierk Hebbeln, Gerard Duineveld, Marc Lavaleye, Katriina Juva, Wolf-Christian Dullo, André Freiwald, Leonardo Tamborrino, Gert-Jan Reichart, Sascha Flögel, and Furu Mienis
Biogeosciences, 16, 4337–4356,Short summary
Along the Namibian and Angolan margins, low oxygen conditions do not meet environmental ranges for cold–water corals and hence are expected to be unsuitable habitats. Environmental conditions show that tidal movements deliver water with more oxygen and high–quality organic matter, suggesting that corals compensate unfavorable conditions with availability of food. With the expected expansion of oxygen minimum zones in the future, this study provides an example how ecosystems cope with extremes.
Alexia Dubuc, Ronald Baker, Cyril Marchand, Nathan J. Waltham, and Marcus Sheaves
Biogeosciences, 16, 3959–3976,Short summary
Little is known about how hypoxia influences mangrove fish assemblages. In situ video observations reveal species-specific avoidance strategies in response to developing hypoxia in a mangrove forest. Taxa commonly using mangroves could withstand hypoxia, while others usually associated with reef habitats were not recorded below 70 % saturation. These results suggest that hypoxia is an important factor shaping mangrove fish assemblages and could explain the low species richness usually observed.
Mariem Saavedra-Pellitero, Karl-Heinz Baumann, Miguel Ángel Fuertes, Hartmut Schulz, Yann Marcon, Nele Manon Vollmar, José-Abel Flores, and Frank Lamy
Biogeosciences, 16, 3679–3702,Short summary
Open ocean phytoplankton include coccolithophore algae, a key element in carbon cycle regulation with important feedbacks to the climate system. We document latitudinal variability in both coccolithophore assemblage and the mass variation in one particular species, Emiliania huxleyi, for a transect across the Drake Passage (in the Southern Ocean). Coccolithophore abundance, diversity and maximum depth habitat decrease southwards, coinciding with changes in the predominant E. huxleyi morphotypes.
Freija Hauquier, Lara Macheriotou, Tania N. Bezerra, Great Egho, Pedro Martínez Arbizu, and Ann Vanreusel
Biogeosciences, 16, 3475–3489,Short summary
Future mining operations in the deep sea provide a source of scientific uncertainty and call for detailed study of the ecosystem. We investigated one of the most diverse and abundant taxa present in deep-sea sediments, nematodes, and demonstrate the importance of sediment attributes for their communities. Especially species that are less common and have a limited spatial distribution will be vulnerable to mining-induced changes. Our findings can serve as a reference for future impact studies.
Haruka Takagi, Katsunori Kimoto, Tetsuichi Fujiki, Hiroaki Saito, Christiane Schmidt, Michal Kucera, and Kazuyoshi Moriya
Biogeosciences, 16, 3377–3396,Short summary
Photosymbiosis (endosymbiosis with algae) is an evolutionary important ecology for many marine organisms but has poorly been identified among planktonic foraminifera. In this study, we identified and characterized photosymbiosis of various species of planktonic foraminifera by focusing on their photosynthesis–related features. We finally proposed a new framework showing a potential strength of photosymbiosis, which will serve as a basis for future ecological studies of planktonic foraminifera.
Abell, G. C. J. and Bowman, J. P.: Ecological and biogeographic relationships of class Flavobacteria in the Southern Ocean, FEMS Microbiol. Ecol., 51, 265–277, 2005.
Agogué, H., Lamy, D., Neal, P. R., Sogin, M. L., and Herndl, G. J.: Water mass-specificity of bacterial communities in the North Atlantic revealed by massively parallel sequencing, Mol. Ecol., 20, 258–274, 2011.
Allgaier, M., Riebesell, U., Vogt, M., Thyrhaug, R., and Grossart, H.-P.: Coupling of heterotrophic bacteria to phytoplankton bloom development at different pCO2 levels: a mesocosm study, Biogeosciences, 5, 1007–1022, https://doi.org/10.5194/bg-5-1007-2008, 2008.
Arnosti, C., Grossart, H. P., Mühling, M., Joint, I., and Passow, U.: Dynamics of extracellular enzyme activities in seawater under changed atmospheric pCO2: a mesocosm investigation, Aquat. Microb. Ecol., 64, 285–298, 2011.
Bellerby, R. G. J., Silyakova, A., Nondal, G., Slagstad, D., Czerny, J., De Lange, T., and Ludwig, A.: Marine carbonate system evolution during the EPOCA Arctic pelagic ecosystem experiment in the context of simulated future Arctic ocean acidification, Biogeosciences, in review, 2013.
Bokulich, N. A., Subramanian, S., Faith, J. J., Gevers, D., Gordon, J. I., Knight, R., Mills, D. A., and Caporaso, J. G.: Quality-filtering vastly improves diversity estimates from Illumina amplicon sequencing, Nat. Methods, 10, 57–59, https://doi.org/10.1038/nmeth.2276, 2013.
Bosch, G., Wang, T., Latypova, E., Kalyuzhnaya, M. G., Hackett, M., and Chistoserdova, L.: Insights into the physiology of Methylotenera mobilis as revealed by metagenome-based shotgun proteomic analysis, Microbiology, 155, 1103–1110, 2009.
Caporaso, J. G., Kuczynski, J., Stombaugh, J., Bittinger, K., Bushman, F. D., Costello, E. K., Fierer, N., Peña, A. G., Goodrich, J. K., Gordon, J. I., Huttley, G. A., Kelley, S. T., Knights, D., Koenig, J. E., Ley, R. E., Lozupone, C. A., McDonald, D., Muegge, B. D, Pirrung, M., Reeder, J., Sevinsky, J. R., Turnbaugh, P. J., Walters, W. A., Widmann, J., Yatsunenko, T., Zaneveld, J., and Knight, R.: QIIME allows analysis of high-throughput community sequencing data, Nat. Methods, 7, 335–336, 2010.
Caporaso, J. G., Lauber, C. L., Walters, W. A., Berg-Lyons, D., Huntley, J., Fierer, N., Owens, S. M., Betley, J., Fraser, L., Bauer, M., Gormley, N., Gilbert, J. A., Smith, G., and Knight, R.: Ultra-high-throughput microbial community analysis on the Illumina HiSeq and MiSeq platforms, ISME J., 6, 1621–1624, https://doi.org/10.1038/ismej.2012.8, 2012.
Chistoserdova, L., Kalyuzhnaya, M. G., and Lapidus, A.: The Expanding World of Methylotrophic Metabolism, Annu. Rev. Microbiol., 63, 477–499, https://doi.org/10.1146/annurev.micro.091208.073600, 2009.
Choi, E. J., Kwon, H. C., Koh, H. Y., Kim, Y. S., and Yang, H. O.: Colwellia asteriadis sp. nov., a marine bacterium isolated from the starfish Asterias amurensis, Int. J. Syst. Evol. Micr., 60, 1952–1957, https://doi.org/10.1099/ijs.0.016055-0, 2010.
Czerny, J., Schulz, K. G., Boxhammer, T., Bellerby, R. G. J., Büdenbender, J., Engel, A., Krug, S. A., Ludwig, A., Nachtigall, K., Nondal, G., Niehoff, B., Siljakova, A., and Riebesell, U.: Element budgets in an Arctic mesocosm CO2 perturbation study, Biogeosciences, in review, 2013a.
Czerny, J., Schulz, K. G., Ludwig, A., and Riebesell, U.: A simple method for gas exchange measurements in mesocosms and its application for carbon budgeting, Biogeosciences, accepted, 2013b.
de Kluijver, A., Soetaert, K., Schulz, K. G., Riebesell, U., Bellerby, R. G. J., and Middelburg, J. J.: Phytoplankton-bacteria coupling under elevated CO2 levels: a stable isotope labelling study, Biogeosciences, 7, 3783–3797, https://doi.org/10.5194/bg-7-3783-2010, 2010.
Delille, B., Harlay, J., Zondervan, I., Jacquet, S., Chou, L., Wollast, R., Bellerby, R. G. J., Frankignoulle, M., Borges, A. V., Riebesell, U., and Gattuso, J. P.: Response of primary production and calcification to changes of pCO2 during experimental blooms of the coccolithophorid Emiliania huxleyi, Global Biogeochem. Cy., 19, GB2023, https://doi.org/10.1029/2004GB002318, 2005.
Falkowski, P. G., Fenchel, T., and Delong, E. F.: The microbial engines that drive Earth's biogeochemical cycles, Science, 320,1034–1039, 2008.
Fu, F.-X., Mulholland, M. R., Garcia, N. S., Beck, A., Bernhardt, P. W., Warner, M. E., Sañudo-Wilhelmy, S. A., and Hutchins, D. A.: Interactions between changing pCO2, N2 fixation, and Fe limitation in the marine unicellular cyanobacterium Crocosphaera, Limnol. Oceanogr., 53, 2472–2484, 2008.
Gilbert, J. A., Field, D., Swift, P., Newbold, L., Oliver A., Smyth, T., Somerfield, P. J., Huse, S., and Joint, I.: The seasonal structure of microbial communities in the Western English Channel, Environ. Microbiol., 11, 3132–3139, 2009.
Grossart, H.-P., Allgaier, M., Passow, U., and Riebesell, U.: Testing the effect of CO2 concentration on dynamics of marine heterotrophic bacterioplankton, Limnol. Oceanogr., 51, 1–11, 2006.
Hubert, J. A., Welch, D. M., Morrison, H. G., Huse, S. M., Neal, P. R., Butterfield, D. A., and Sogin, M. L.: Microbial population structures in the deep marine biosphere, Science, 318, 97–100, https://doi.org/10.1126/science.1146689, 2007.
Huse, S. M., Dethlefsen, L., Huber, J. A., Welch, D. M., Relman, D. A., and Sogin, M. L.: Exploring Microbial Diversity and Taxonomy Using SSU rRNA Hypervariable Tag Sequencing, PLoS Genet, 4, e1000255, https://doi.org/10.1371/journal.pgen.1000255, 2008.
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