Articles | Volume 15, issue 8
https://doi.org/10.5194/bg-15-2565-2018
© Author(s) 2018. 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-15-2565-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
02 May 2018
Research article |
| 02 May 2018
| 02 May 2018
N2 fixation as a dominant new N source in the western tropical South Pacific Ocean (OUTPACE cruise)
Mathieu Caffin
CORRESPONDING AUTHOR
Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
Thierry Moutin
Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
Rachel Ann Foster
Stockholm University, Department of Ecology, Environment and Plant
Sciences, Stockholm, Sweden
Pascale Bouruet-Aubertot
Sorbonne Universités, UPMC Univ. Paris 06, LOCEAN, Paris, France
Andrea Michelangelo Doglioli
Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
Hugo Berthelot
Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
Laboratoire des sciences de l'environnement marin, IUEM,
Université de Brest-UMR 6539 CNRS/UBO/IRD/Ifremer, Plouzané, France
Cécile Guieu
Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire
d'Océanographie de Villefranche (LOV), 06230 Villefranche-sur-Mer, France
The Center for Prototype Climate Modeling, New York University in Abu Dhabi, Abu Dhabi, UAE
Olivier Grosso
Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
Sandra Helias-Nunige
Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
Nathalie Leblond
Observatoire Océanologique de Villefranche, Laboratoire
d'Océanographie de Villefranche, UMR 7093, Villefranche-sur-mer, France
Audrey Gimenez
Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
Anne Alexandra Petrenko
Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
Alain de Verneil
Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
now at: The Center for Prototype Climate Modeling, New York University in Abu Dhabi, Abu Dhabi, UAE
Sophie Bonnet
Aix Marseille Université, CNRS, Université de Toulon, IRD, OSU
Pythéas, Mediterranean Institute of Oceanography (MIO), UM 110, 98848,
Nouméa, New Caledonia
Related authors
Pascale Bouruet-Aubertot, Yannis Cuypers, Andrea Doglioli, Mathieu Caffin, Christophe Yohia, Alain de Verneil, Anne Petrenko, Dominique Lefèvre, Hervé Le Goff, Gilles Rougier, Marc Picheral, and Thierry Moutin
Biogeosciences, 15, 7485–7504, https://doi.org/10.5194/bg-15-7485-2018, https://doi.org/10.5194/bg-15-7485-2018, 2018
Short summary
Short summary
The OUTPACE cruise took place between New Caledonia and French Polynesia. The main purpose was to understand how micro-organisms can survive in a very poor environment. One main source of nutrients is at depth, below the euphotic layer where micro-organisms live. The purpose of the turbulence measurements was to determine to which extent turbulence may
upliftnutrients into the euphotic layer. The origin of the turbulence that was found contrasted along the transect was also determined.
Thibaut Wagener, Nicolas Metzl, Mathieu Caffin, Jonathan Fin, Sandra Helias Nunige, Dominique Lefevre, Claire Lo Monaco, Gilles Rougier, and Thierry Moutin
Biogeosciences, 15, 5221–5236, https://doi.org/10.5194/bg-15-5221-2018, https://doi.org/10.5194/bg-15-5221-2018, 2018
Short summary
Short summary
The western tropical South Pacific was sampled along a longitudinal 4000 km transect (OUTPACE cruise) for the measurement of carbonate parameters (total alkalinity and total inorganic carbon) between the Melanesian Archipelago and the western part of the South Pacific gyre. This paper reports this new dataset and derived properties. We also estimate anthropogenic carbon distribution in the water column using the TrOCA method.
Sophie Bonnet, Mathieu Caffin, Hugo Berthelot, Olivier Grosso, Mar Benavides, Sandra Helias-Nunige, Cécile Guieu, Marcus Stenegren, and Rachel Ann Foster
Biogeosciences, 15, 4215–4232, https://doi.org/10.5194/bg-15-4215-2018, https://doi.org/10.5194/bg-15-4215-2018, 2018
Mathieu Caffin, Hugo Berthelot, Véronique Cornet-Barthaux, Aude Barani, and Sophie Bonnet
Biogeosciences, 15, 3795–3810, https://doi.org/10.5194/bg-15-3795-2018, https://doi.org/10.5194/bg-15-3795-2018, 2018
Thierry Moutin, Thibaut Wagener, Mathieu Caffin, Alain Fumenia, Audrey Gimenez, Melika Baklouti, Pascale Bouruet-Aubertot, Mireille Pujo-Pay, Karine Leblanc, Dominique Lefevre, Sandra Helias Nunige, Nathalie Leblond, Olivier Grosso, and Alain de Verneil
Biogeosciences, 15, 2961–2989, https://doi.org/10.5194/bg-15-2961-2018, https://doi.org/10.5194/bg-15-2961-2018, 2018
Short summary
Short summary
Surface waters of the western tropical South Pacific were sampled along a longitudinal 4000 km transect during the stratified period between the Melanesian Archipelago and the western part of the South Pacific gyre. We found a significant biological carbon pump sustained almost exclusively by N2 fixation and essentially controlled by phosphate availability in the iron-rich Melanesian Archipelago waters which appears to be a net sink for atmospheric CO2 while the gyre is in a quasi-steady state.
Julika Zinke, Gabriel Freitas, Rachel Ann Foster, Paul Zieger, Ernst Douglas Nilsson, Piotr Markuszewski, and Matthew Edward Salter
EGUsphere, https://doi.org/10.5194/egusphere-2024-1851, https://doi.org/10.5194/egusphere-2024-1851, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Bioaerosols, which can influence climate and human health, were studied in the Baltic Sea. In May and August 2021, we used a sea spray simulation chamber on two ship based campaigns to collect and measure these aerosols. We found that bacteria were enriched in the air compared to seawater. Bacterial diversity was analyzed using DNA sequencing. Our methods provided consistent estimates of bacterial emission fluxes, aligning with previous studies.
France Van Wambeke, Pascal Conan, Mireille Pujo-Pay, Vincent Taillandier, Olivier Crispi, Alexandra Pavlidou, Sandra Nunige, Morgane Didry, Christophe Salmeron, and Elvira Pulido-Villena
Biogeosciences, 21, 2621–2640, https://doi.org/10.5194/bg-21-2621-2024, https://doi.org/10.5194/bg-21-2621-2024, 2024
Short summary
Short summary
Phosphomonoesterase (PME) and phosphodiesterase (PDE) activities over the epipelagic zone are described in the eastern Mediterranean Sea in winter and autumn. The types of concentration kinetics obtained for PDE (saturation at 50 µM, high Km, high turnover times) compared to those of PME (saturation at 1 µM, low Km, low turnover times) are discussed in regard to the possible inequal distribution of PDE and PME in the size continuum of organic material and accessibility to phosphodiesters.
Nicolas Metzl, Jonathan Fin, Claire Lo Monaco, Claude Mignon, Samir Alliouane, David Antoine, Guillaume Bourdin, Jacqueline Boutin, Yann Bozec, Pascal Conan, Laurent Coppola, Frédéric Diaz, Eric Douville, Xavier Durrieu de Madron, Jean-Pierre Gattuso, Frédéric Gazeau, Melek Golbol, Bruno Lansard, Dominique Lefèvre, Nathalie Lefèvre, Fabien Lombard, Férial Louanchi, Liliane Merlivat, Léa Olivier, Anne Petrenko, Sébastien Petton, Mireille Pujo-Pay, Christophe Rabouille, Gilles Reverdin, Céline Ridame, Aline Tribollet, Vincenzo Vellucci, Thibaut Wagener, and Cathy Wimart-Rousseau
Earth Syst. Sci. Data, 16, 89–120, https://doi.org/10.5194/essd-16-89-2024, https://doi.org/10.5194/essd-16-89-2024, 2024
Short summary
Short summary
This work presents a synthesis of 44 000 total alkalinity and dissolved inorganic carbon observations obtained between 1993 and 2022 in the Global Ocean and the Mediterranean Sea at the surface and in the water column. Seawater samples were measured using the same method and calibrated with international Certified Reference Material. We describe the data assemblage, quality control and some potential uses of this dataset.
Roxane Tzortzis, Andrea M. Doglioli, Monique Messié, Stéphanie Barrillon, Anne A. Petrenko, Lloyd Izard, Yuan Zhao, Francesco d'Ovidio, Franck Dumas, and Gérald Gregori
Biogeosciences, 20, 3491–3508, https://doi.org/10.5194/bg-20-3491-2023, https://doi.org/10.5194/bg-20-3491-2023, 2023
Short summary
Short summary
We studied a finescale frontal structure in order to highlight its influence on the dynamics and distribution of phytoplankton communities. We computed the growth rates of several phytoplankton groups identified by flow cytometry in two water masses separated by the front. We found contrasted phytoplankton dynamics on the two sides of the front, consistent with the distribution of their abundances. Our study gives new insights into the physical and biological coupling on a finescale front.
Zhibo Shao, Yangchun Xu, Hua Wang, Weicheng Luo, Lice Wang, Yuhong Huang, Nona Sheila R. Agawin, Ayaz Ahmed, Mar Benavides, Mikkel Bentzon-Tilia, Ilana Berman-Frank, Hugo Berthelot, Isabelle C. Biegala, Mariana B. Bif, Antonio Bode, Sophie Bonnet, Deborah A. Bronk, Mark V. Brown, Lisa Campbell, Douglas G. Capone, Edward J. Carpenter, Nicolas Cassar, Bonnie X. Chang, Dreux Chappell, Yuh-ling Lee Chen, Matthew J. Church, Francisco M. Cornejo-Castillo, Amália Maria Sacilotto Detoni, Scott C. Doney, Cecile Dupouy, Marta Estrada, Camila Fernandez, Bieito Fernández-Castro, Debany Fonseca-Batista, Rachel A. Foster, Ken Furuya, Nicole Garcia, Kanji Goto, Jesús Gago, Mary R. Gradoville, M. Robert Hamersley, Britt A. Henke, Cora Hörstmann, Amal Jayakumar, Zhibing Jiang, Shuh-Ji Kao, David M. Karl, Leila R. Kittu, Angela N. Knapp, Sanjeev Kumar, Julie LaRoche, Hongbin Liu, Jiaxing Liu, Caroline Lory, Carolin R. Löscher, Emilio Marañón, Lauren F. Messer, Matthew M. Mills, Wiebke Mohr, Pia H. Moisander, Claire Mahaffey, Robert Moore, Beatriz Mouriño-Carballido, Margaret R. Mulholland, Shin-ichiro Nakaoka, Joseph A. Needoba, Eric J. Raes, Eyal Rahav, Teodoro Ramírez-Cárdenas, Christian Furbo Reeder, Lasse Riemann, Virginie Riou, Julie C. Robidart, Vedula V. S. S. Sarma, Takuya Sato, Himanshu Saxena, Corday Selden, Justin R. Seymour, Dalin Shi, Takuhei Shiozaki, Arvind Singh, Rachel E. Sipler, Jun Sun, Koji Suzuki, Kazutaka Takahashi, Yehui Tan, Weiyi Tang, Jean-Éric Tremblay, Kendra Turk-Kubo, Zuozhu Wen, Angelicque E. White, Samuel T. Wilson, Takashi Yoshida, Jonathan P. Zehr, Run Zhang, Yao Zhang, and Ya-Wei Luo
Earth Syst. Sci. Data, 15, 3673–3709, https://doi.org/10.5194/essd-15-3673-2023, https://doi.org/10.5194/essd-15-3673-2023, 2023
Short summary
Short summary
N2 fixation by marine diazotrophs is an important bioavailable N source to the global ocean. This updated global oceanic diazotroph database increases the number of in situ measurements of N2 fixation rates, diazotrophic cell abundances, and nifH gene copy abundances by 184 %, 86 %, and 809 %, respectively. Using the updated database, the global marine N2 fixation rate is estimated at 223 ± 30 Tg N yr−1, which triplicates that using the original database.
Stéphanie Barrillon, Robin Fuchs, Anne A. Petrenko, Caroline Comby, Anthony Bosse, Christophe Yohia, Jean-Luc Fuda, Nagib Bhairy, Frédéric Cyr, Andrea M. Doglioli, Gérald Grégori, Roxane Tzortzis, Francesco d'Ovidio, and Melilotus Thyssen
Biogeosciences, 20, 141–161, https://doi.org/10.5194/bg-20-141-2023, https://doi.org/10.5194/bg-20-141-2023, 2023
Short summary
Short summary
Extreme weather events can have a major impact on ocean physics and biogeochemistry, but their study is challenging. In May 2019, an intense storm occurred in the north-western Mediterranean Sea, during which in situ multi-platform measurements were performed. The results show a strong impact on the surface phytoplankton, highlighting the need for high-resolution measurements coupling physics and biology during these violent events that may become more common in the context of global change.
Julie Dinasquet, Estelle Bigeard, Frédéric Gazeau, Farooq Azam, Cécile Guieu, Emilio Marañón, Céline Ridame, France Van Wambeke, Ingrid Obernosterer, and Anne-Claire Baudoux
Biogeosciences, 19, 1303–1319, https://doi.org/10.5194/bg-19-1303-2022, https://doi.org/10.5194/bg-19-1303-2022, 2022
Short summary
Short summary
Saharan dust deposition of nutrients and trace metals is crucial to microbes in the Mediterranean Sea. Here, we tested the response of microbial and viral communities to simulated dust deposition under present and future conditions of temperature and pH. Overall, the effect of the deposition was dependent on the initial microbial assemblage, and future conditions will intensify microbial responses. We observed effects on trophic interactions, cascading all the way down to viral processes.
Alain de Verneil, Zouhair Lachkar, Shafer Smith, and Marina Lévy
Biogeosciences, 19, 907–929, https://doi.org/10.5194/bg-19-907-2022, https://doi.org/10.5194/bg-19-907-2022, 2022
Short summary
Short summary
The Arabian Sea is a natural CO2 source to the atmosphere, but previous work highlights discrepancies between data and models in estimating air–sea CO2 flux. In this study, we use a regional ocean model, achieve a flux closer to available data, and break down the seasonal cycles that impact it, with one result being the great importance of monsoon winds. As demonstrated in a meta-analysis, differences from data still remain, highlighting the great need for further regional data collection.
Céline Ridame, Julie Dinasquet, Søren Hallstrøm, Estelle Bigeard, Lasse Riemann, France Van Wambeke, Matthieu Bressac, Elvira Pulido-Villena, Vincent Taillandier, Fréderic Gazeau, Antonio Tovar-Sanchez, Anne-Claire Baudoux, and Cécile Guieu
Biogeosciences, 19, 415–435, https://doi.org/10.5194/bg-19-415-2022, https://doi.org/10.5194/bg-19-415-2022, 2022
Short summary
Short summary
We show that in the Mediterranean Sea spatial variability in N2 fixation is related to the diazotrophic community composition reflecting different nutrient requirements among species. Nutrient supply by Saharan dust is of great importance to diazotrophs, as shown by the strong stimulation of N2 fixation after a simulated dust event under present and future climate conditions; the magnitude of stimulation depends on the degree of limitation related to the diazotrophic community composition.
Roxane Tzortzis, Andrea M. Doglioli, Stéphanie Barrillon, Anne A. Petrenko, Francesco d'Ovidio, Lloyd Izard, Melilotus Thyssen, Ananda Pascual, Bàrbara Barceló-Llull, Frédéric Cyr, Marc Tedetti, Nagib Bhairy, Pierre Garreau, Franck Dumas, and Gérald Gregori
Biogeosciences, 18, 6455–6477, https://doi.org/10.5194/bg-18-6455-2021, https://doi.org/10.5194/bg-18-6455-2021, 2021
Short summary
Short summary
This work analyzes an original high-resolution data set collected in the Mediterranean Sea. The major result is the impact of a fine-scale frontal structure on the distribution of phytoplankton groups, in an area of moderate energy with oligotrophic conditions. Our results provide an in situ confirmation of the findings obtained by previous modeling studies and remote sensing about the structuring effect of the fine-scale ocean dynamics on the structure of the phytoplankton community.
Matthieu Bressac, Thibaut Wagener, Nathalie Leblond, Antonio Tovar-Sánchez, Céline Ridame, Vincent Taillandier, Samuel Albani, Sophie Guasco, Aurélie Dufour, Stéphanie H. M. Jacquet, François Dulac, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 18, 6435–6453, https://doi.org/10.5194/bg-18-6435-2021, https://doi.org/10.5194/bg-18-6435-2021, 2021
Short summary
Short summary
Phytoplankton growth is limited by the availability of iron in about 50 % of the ocean. Atmospheric deposition of desert dust represents a key source of iron. Here, we present direct observations of dust deposition in the Mediterranean Sea. A key finding is that the input of iron from dust primarily occurred in the deep ocean, while previous studies mainly focused on the ocean surface. This new insight will enable us to better represent controls on global marine productivity in models.
Léo Berline, Andrea Michelangelo Doglioli, Anne Petrenko, Stéphanie Barrillon, Boris Espinasse, Frederic A. C. Le Moigne, François Simon-Bot, Melilotus Thyssen, and François Carlotti
Biogeosciences, 18, 6377–6392, https://doi.org/10.5194/bg-18-6377-2021, https://doi.org/10.5194/bg-18-6377-2021, 2021
Short summary
Short summary
While the Ionian Sea is considered a nutrient-depleted and low-phytoplankton biomass area, it is a crossroad for water mass circulation. In the central Ionian Sea, we observed a strong contrast in particle distribution across a ~100 km long transect. Using remote sensing and Lagrangian simulations, we suggest that this contrast finds its origin in the long-distance transport of particles from the north, west and east of the Ionian Sea, where phytoplankton production was more intense.
Elvira Pulido-Villena, Karine Desboeufs, Kahina Djaoudi, France Van Wambeke, Stéphanie Barrillon, Andrea Doglioli, Anne Petrenko, Vincent Taillandier, Franck Fu, Tiphanie Gaillard, Sophie Guasco, Sandra Nunige, Sylvain Triquet, and Cécile Guieu
Biogeosciences, 18, 5871–5889, https://doi.org/10.5194/bg-18-5871-2021, https://doi.org/10.5194/bg-18-5871-2021, 2021
Short summary
Short summary
We report on phosphorus dynamics in the surface layer of the Mediterranean Sea. Highly sensitive phosphate measurements revealed vertical gradients above the phosphacline. The relative contribution of diapycnal fluxes to total external supply of phosphate to the mixed layer decreased towards the east, where atmospheric deposition dominated. Taken together, external sources of phosphate contributed little to total supply, which was mainly sustained by enzymatic hydrolysis of organic phosphorus.
Frédéric Gazeau, France Van Wambeke, Emilio Marañón, Maria Pérez-Lorenzo, Samir Alliouane, Christian Stolpe, Thierry Blasco, Nathalie Leblond, Birthe Zäncker, Anja Engel, Barbara Marie, Julie Dinasquet, and Cécile Guieu
Biogeosciences, 18, 5423–5446, https://doi.org/10.5194/bg-18-5423-2021, https://doi.org/10.5194/bg-18-5423-2021, 2021
Short summary
Short summary
Our study shows that the impact of dust deposition on primary production depends on the initial composition and metabolic state of the tested community and is constrained by the amount of nutrients added, to sustain both the fast response of heterotrophic prokaryotes and the delayed one of phytoplankton. Under future environmental conditions, heterotrophic metabolism will be more impacted than primary production, therefore reducing the capacity of surface waters to sequester anthropogenic CO2.
Frédéric Gazeau, Céline Ridame, France Van Wambeke, Samir Alliouane, Christian Stolpe, Jean-Olivier Irisson, Sophie Marro, Jean-Michel Grisoni, Guillaume De Liège, Sandra Nunige, Kahina Djaoudi, Elvira Pulido-Villena, Julie Dinasquet, Ingrid Obernosterer, Philippe Catala, and Cécile Guieu
Biogeosciences, 18, 5011–5034, https://doi.org/10.5194/bg-18-5011-2021, https://doi.org/10.5194/bg-18-5011-2021, 2021
Short summary
Short summary
This paper shows that the impacts of Saharan dust deposition in different Mediterranean basins are as strong as those observed in coastal waters but differed substantially between the three tested stations, differences attributed to variable initial metabolic states. A stronger impact of warming and acidification on mineralization suggests a decreased capacity of Mediterranean surface communities to sequester CO2 following the deposition of atmospheric particles in the coming decades.
Evelyn Freney, Karine Sellegri, Alessia Nicosia, Leah R. Williams, Matteo Rinaldi, Jonathan T. Trueblood, André S. H. Prévôt, Melilotus Thyssen, Gérald Grégori, Nils Haëntjens, Julie Dinasquet, Ingrid Obernosterer, France Van Wambeke, Anja Engel, Birthe Zäncker, Karine Desboeufs, Eija Asmi, Hilkka Timonen, and Cécile Guieu
Atmos. Chem. Phys., 21, 10625–10641, https://doi.org/10.5194/acp-21-10625-2021, https://doi.org/10.5194/acp-21-10625-2021, 2021
Short summary
Short summary
In this work, we present observations of the organic aerosol content in primary sea spray aerosols (SSAs) continuously generated along a 5-week cruise in the Mediterranean. This information is combined with seawater biogeochemical properties also measured continuously along the ship track to develop a number of parametrizations that can be used in models to determine SSA organic content in oligotrophic waters that represent 60 % of the oceans from commonly measured seawater variables.
Matthieu Roy-Barman, Lorna Foliot, Eric Douville, Nathalie Leblond, Fréderic Gazeau, Matthieu Bressac, Thibaut Wagener, Céline Ridame, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 18, 2663–2678, https://doi.org/10.5194/bg-18-2663-2021, https://doi.org/10.5194/bg-18-2663-2021, 2021
Short summary
Short summary
The release of insoluble elements such as aluminum (Al), iron (Fe), rare earth elements (REEs), thorium (Th) and protactinium (Pa) when Saharan dust falls over the Mediterranean Sea was studied during tank experiments under present and future climate conditions. Each element exhibited different dissolution kinetics and dissolution fractions (always lower than a few percent). Changes in temperature and/or pH under greenhouse conditions lead to a lower Th release and a higher light REE release.
Siqi Wu, Moge Du, Xianhui Sean Wan, Corday Selden, Mar Benavides, Sophie Bonnet, Robert Hamersley, Carolin R. Löscher, Margaret R. Mulholland, Xiuli Yan, and Shuh-Ji Kao
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-104, https://doi.org/10.5194/bg-2021-104, 2021
Preprint withdrawn
Short summary
Short summary
Nitrogen (N2) fixation is one of the most important nutrient sources to the ocean. Here, we report N2 fixation in the deep, dark ocean in the South China Sea via a highly sensitive new method and elaborate controls, showing the overlooked importance of N2 fixation in the deep ocean. By global data compilation, we also provide an easy measured basic parameter to estimate deep N2 fixation. Our study may help to expand the area limit of N2 fixation studies and better constrain global N2 fixation.
Jonathan V. Trueblood, Alessia Nicosia, Anja Engel, Birthe Zäncker, Matteo Rinaldi, Evelyn Freney, Melilotus Thyssen, Ingrid Obernosterer, Julie Dinasquet, Franco Belosi, Antonio Tovar-Sánchez, Araceli Rodriguez-Romero, Gianni Santachiara, Cécile Guieu, and Karine Sellegri
Atmos. Chem. Phys., 21, 4659–4676, https://doi.org/10.5194/acp-21-4659-2021, https://doi.org/10.5194/acp-21-4659-2021, 2021
Short summary
Short summary
Sea spray aerosols (SSAs) can be an important source of ice-nucleating particles (INPs) that impact cloud properties over the oceans. In the Mediterranean Sea, we found that the INPs in the seawater surface microlayer increased by an order of magnitude after a rain dust event that impacted iron and bacterial abundances. The INP properties of SSA (INPSSA) increased after a 3 d delay. Outside this event, INPSSA could be parameterized as a function of the seawater biogeochemistry.
Kahina Djaoudi, France Van Wambeke, Aude Barani, Nagib Bhairy, Servanne Chevaillier, Karine Desboeufs, Sandra Nunige, Mohamed Labiadh, Thierry Henry des Tureaux, Dominique Lefèvre, Amel Nouara, Christos Panagiotopoulos, Marc Tedetti, and Elvira Pulido-Villena
Biogeosciences, 17, 6271–6285, https://doi.org/10.5194/bg-17-6271-2020, https://doi.org/10.5194/bg-17-6271-2020, 2020
Cécile Guieu, Fabrizio D'Ortenzio, François Dulac, Vincent Taillandier, Andrea Doglioli, Anne Petrenko, Stéphanie Barrillon, Marc Mallet, Pierre Nabat, and Karine Desboeufs
Biogeosciences, 17, 5563–5585, https://doi.org/10.5194/bg-17-5563-2020, https://doi.org/10.5194/bg-17-5563-2020, 2020
Short summary
Short summary
We describe here the objectives and strategy of the PEACETIME project and cruise, dedicated to dust deposition and its impacts in the Mediterranean Sea. Our strategy to go a step further forward than in previous approaches in understanding these impacts by catching a real deposition event at sea is detailed. We summarize the work performed at sea, the type of data acquired and their valorization in the papers published in the special issue.
Antonio Tovar-Sánchez, Araceli Rodríguez-Romero, Anja Engel, Birthe Zäncker, Franck Fu, Emilio Marañón, María Pérez-Lorenzo, Matthieu Bressac, Thibaut Wagener, Sylvain Triquet, Guillaume Siour, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 17, 2349–2364, https://doi.org/10.5194/bg-17-2349-2020, https://doi.org/10.5194/bg-17-2349-2020, 2020
Short summary
Short summary
Residence times of particulate metals derived from aerosol deposition in the Sea Surface Microlayer of the Mediterranean Sea ranged from a couple of minutes (e.g., for Fe) to a few hours (e.g., for Cu). Microbial activity seems to play an important role in in this process and in the concentration and distribution of metals between diferent water layers.
Pierre Garreau, Franck Dumas, Stéphanie Louazel, Stéphanie Correard, Solenn Fercocq, Marc Le Menn, Alain Serpette, Valérie Garnier, Alexandre Stegner, Briac Le Vu, Andrea Doglioli, and Gerald Gregori
Earth Syst. Sci. Data, 12, 441–456, https://doi.org/10.5194/essd-12-441-2020, https://doi.org/10.5194/essd-12-441-2020, 2020
Short summary
Short summary
The oceanic circulation is composed of the main currents, of large eddies and meanders, and of fine motions at a scale of about a few hundreds of metres, rarely observed in situ. PROTEVS-MED experiments were devoted to very high resolution observations of water properties (temperature and salinity) and currents, thanks to an undulating trawled vehicle revealing a patchy, stirred and energetic ocean in the first 400 m depth. These fine-scale dynamics drive the plankton and air–sea exchanges.
Thierry Moutin
Biogeosciences, 16, 1673–1673, https://doi.org/10.5194/bg-16-1673-2019, https://doi.org/10.5194/bg-16-1673-2019, 2019
Pascale Bouruet-Aubertot, Yannis Cuypers, Andrea Doglioli, Mathieu Caffin, Christophe Yohia, Alain de Verneil, Anne Petrenko, Dominique Lefèvre, Hervé Le Goff, Gilles Rougier, Marc Picheral, and Thierry Moutin
Biogeosciences, 15, 7485–7504, https://doi.org/10.5194/bg-15-7485-2018, https://doi.org/10.5194/bg-15-7485-2018, 2018
Short summary
Short summary
The OUTPACE cruise took place between New Caledonia and French Polynesia. The main purpose was to understand how micro-organisms can survive in a very poor environment. One main source of nutrients is at depth, below the euphotic layer where micro-organisms live. The purpose of the turbulence measurements was to determine to which extent turbulence may
upliftnutrients into the euphotic layer. The origin of the turbulence that was found contrasted along the transect was also determined.
François Carlotti, Marc Pagano, Loïc Guilloux, Katty Donoso, Valentina Valdés, Olivier Grosso, and Brian P. V. Hunt
Biogeosciences, 15, 7273–7297, https://doi.org/10.5194/bg-15-7273-2018, https://doi.org/10.5194/bg-15-7273-2018, 2018
Short summary
Short summary
The paper characterizes the zooplankton community and plankton food web processes between New Caledonia and Tahiti (tropical South Pacific) during the austral summer 2015. In this region, the pelagic production depends on N2 fixation by diazotroph microorganisms on which the zooplankton community feeds, supporting a pelagic food chain ending with valuable tuna fisheries. We estimated a contribution of up to 75 % of diazotroph‐derived nitrogen to zooplankton biomass in the Melanesian archipelago.
Stelios Myriokefalitakis, Akinori Ito, Maria Kanakidou, Athanasios Nenes, Maarten C. Krol, Natalie M. Mahowald, Rachel A. Scanza, Douglas S. Hamilton, Matthew S. Johnson, Nicholas Meskhidze, Jasper F. Kok, Cecile Guieu, Alex R. Baker, Timothy D. Jickells, Manmohan M. Sarin, Srinivas Bikkina, Rachel Shelley, Andrew Bowie, Morgane M. G. Perron, and Robert A. Duce
Biogeosciences, 15, 6659–6684, https://doi.org/10.5194/bg-15-6659-2018, https://doi.org/10.5194/bg-15-6659-2018, 2018
Short summary
Short summary
The first atmospheric iron (Fe) deposition model intercomparison is presented in this study, as a result of the deliberations of the United Nations Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP; http://www.gesamp.org/) Working Group 38. We conclude that model diversity over remote oceans reflects uncertainty in the Fe content parameterizations of dust aerosols, combustion aerosol emissions and the size distribution of transported aerosol Fe.
Audrey Gimenez, Melika Baklouti, Thibaut Wagener, and Thierry Moutin
Biogeosciences, 15, 6573–6589, https://doi.org/10.5194/bg-15-6573-2018, https://doi.org/10.5194/bg-15-6573-2018, 2018
Short summary
Short summary
During the OUTPACE cruise conducted in the oligotrophic to ultra-oligotrophic region of the western tropical South Pacific, two contrasted regions were sampled in terms of N2 fixation rates, primary production rates and nutrient availability. The aim of this work was to investigate the role of N2 fixation in the differences observed between the two contrasted areas by comparing two simulations only differing by the presence or not of N2 fixers using a 1-D biogeochemical–physical coupled model.
Kyle R. Frischkorn, Andreas Krupke, Cécile Guieu, Justine Louis, Mónica Rouco, Andrés E. Salazar Estrada, Benjamin A. S. Van Mooy, and Sonya T. Dyhrman
Biogeosciences, 15, 5761–5778, https://doi.org/10.5194/bg-15-5761-2018, https://doi.org/10.5194/bg-15-5761-2018, 2018
Short summary
Short summary
Trichodesmium is a keystone genus of marine cyanobacteria that is estimated to supply nearly half of the ocean’s fixed nitrogen, fuelling primary productivity and the cycling of carbon and nitrogen in the ocean. In our study we characterize Trichodesmium ecology across the western tropical South Pacific using gene and genome sequencing and geochemistry. We detected genes for phosphorus reduction, providing a mechanism for the noted importance of this organism in the ocean's phosphorus cycle.
Karine Leblanc, Véronique Cornet, Peggy Rimmelin-Maury, Olivier Grosso, Sandra Hélias-Nunige, Camille Brunet, Hervé Claustre, Joséphine Ras, Nathalie Leblond, and Bernard Quéguiner
Biogeosciences, 15, 5595–5620, https://doi.org/10.5194/bg-15-5595-2018, https://doi.org/10.5194/bg-15-5595-2018, 2018
Short summary
Short summary
The Si biogeochemical cycle was studied during two oceanographic cruises in the tropical South Pacific in 2005 and 2015, between New Caledonia and the Chilean upwelling (8–34° S). Some of the lowest levels of biogenic silica stocks were found in the southern Pacific gyre, where Chlorophyll a concentrations are most depleted worldwide. Size-fractionated biogenic silica concentrations as well as Si kinetic uptake experiments revealed biological Si uptake by the picoplanktonic size fraction.
Thibaut Wagener, Nicolas Metzl, Mathieu Caffin, Jonathan Fin, Sandra Helias Nunige, Dominique Lefevre, Claire Lo Monaco, Gilles Rougier, and Thierry Moutin
Biogeosciences, 15, 5221–5236, https://doi.org/10.5194/bg-15-5221-2018, https://doi.org/10.5194/bg-15-5221-2018, 2018
Short summary
Short summary
The western tropical South Pacific was sampled along a longitudinal 4000 km transect (OUTPACE cruise) for the measurement of carbonate parameters (total alkalinity and total inorganic carbon) between the Melanesian Archipelago and the western part of the South Pacific gyre. This paper reports this new dataset and derived properties. We also estimate anthropogenic carbon distribution in the water column using the TrOCA method.
Marine Bretagnon, Aurélien Paulmier, Véronique Garçon, Boris Dewitte, Séréna Illig, Nathalie Leblond, Laurent Coppola, Fernando Campos, Federico Velazco, Christos Panagiotopoulos, Andreas Oschlies, J. Martin Hernandez-Ayon, Helmut Maske, Oscar Vergara, Ivonne Montes, Philippe Martinez, Edgardo Carrasco, Jacques Grelet, Olivier Desprez-De-Gesincourt, Christophe Maes, and Lionel Scouarnec
Biogeosciences, 15, 5093–5111, https://doi.org/10.5194/bg-15-5093-2018, https://doi.org/10.5194/bg-15-5093-2018, 2018
Short summary
Short summary
In oxygen minimum zone, the fate of the organic matter is a key question as the low oxygen condition would preserve the OM and thus enhance the biological carbon pump while the high microbial activity would foster the remineralisation and the greenhouse gases emission. To investigate this paradigm, sediment traps were deployed off Peru. We pointed out the influence of the oxygenation as well as the organic matter quantity and quality on the carbon transfer efficiency in the oxygen minimum zone.
Sophie Bonnet, Mathieu Caffin, Hugo Berthelot, Olivier Grosso, Mar Benavides, Sandra Helias-Nunige, Cécile Guieu, Marcus Stenegren, and Rachel Ann Foster
Biogeosciences, 15, 4215–4232, https://doi.org/10.5194/bg-15-4215-2018, https://doi.org/10.5194/bg-15-4215-2018, 2018
Simon Barbot, Anne Petrenko, and Christophe Maes
Biogeosciences, 15, 4103–4124, https://doi.org/10.5194/bg-15-4103-2018, https://doi.org/10.5194/bg-15-4103-2018, 2018
Short summary
Short summary
In the context of the OUTPACE cruise and THOT project in the western South Pacific Ocean, we use individual float trajectories in order to understand the intermediate-flow dynamics, from 300 to 1000 m depth. We highlight two main features: exchanges of water between parallel jets entering the Coral Sea through eddies and intermediate-wave influence of the currents in the frontal area connecting the Antarctic intermediate water (AAIW) and North Pacific deep water (NPDW) masses.
Dina Spungin, Natalia Belkin, Rachel A. Foster, Marcus Stenegren, Andrea Caputo, Mireille Pujo-Pay, Nathalie Leblond, Cécile Dupouy, Sophie Bonnet, and Ilana Berman-Frank
Biogeosciences, 15, 3893–3908, https://doi.org/10.5194/bg-15-3893-2018, https://doi.org/10.5194/bg-15-3893-2018, 2018
Short summary
Short summary
The way marine organisms die can determine the fate of organic matter (OM) in the ocean. We investigated whether a form of auto-induced programmed cell death (PCD) influenced phytoplankton mortality and fate of OM. Our results from high biomass blooms of the cyanobacterium Trichodesmium show evidence for PCD and high production of sticky carbon material termed transparent exopolymeric particles (TEP) that facilitates cellular aggregation and enhances the vertical flux of OM to depth.
Mathieu Caffin, Hugo Berthelot, Véronique Cornet-Barthaux, Aude Barani, and Sophie Bonnet
Biogeosciences, 15, 3795–3810, https://doi.org/10.5194/bg-15-3795-2018, https://doi.org/10.5194/bg-15-3795-2018, 2018
Mar Benavides, Katyanne M. Shoemaker, Pia H. Moisander, Jutta Niggemann, Thorsten Dittmar, Solange Duhamel, Olivier Grosso, Mireille Pujo-Pay, Sandra Hélias-Nunige, Alain Fumenia, and Sophie Bonnet
Biogeosciences, 15, 3107–3119, https://doi.org/10.5194/bg-15-3107-2018, https://doi.org/10.5194/bg-15-3107-2018, 2018
Short summary
Short summary
We measured N2 fixation rates and identified diazotrophic phylotypes in the mesopelagic layer along a transect spanning from New Caledonia to French Polynesia. N2 fixation rates were low but consistently detected across all depths and stations. A distinct diazotrophic phylotype dominated at 650 dbar, coinciding with the oxygenated Subantarctic Mode Water (SAMW) and suggesting that the distribution of aphotic diazotroph communities is to some extent controlled by water mass structure.
Thierry Moutin, Thibaut Wagener, Mathieu Caffin, Alain Fumenia, Audrey Gimenez, Melika Baklouti, Pascale Bouruet-Aubertot, Mireille Pujo-Pay, Karine Leblanc, Dominique Lefevre, Sandra Helias Nunige, Nathalie Leblond, Olivier Grosso, and Alain de Verneil
Biogeosciences, 15, 2961–2989, https://doi.org/10.5194/bg-15-2961-2018, https://doi.org/10.5194/bg-15-2961-2018, 2018
Short summary
Short summary
Surface waters of the western tropical South Pacific were sampled along a longitudinal 4000 km transect during the stratified period between the Melanesian Archipelago and the western part of the South Pacific gyre. We found a significant biological carbon pump sustained almost exclusively by N2 fixation and essentially controlled by phosphate availability in the iron-rich Melanesian Archipelago waters which appears to be a net sink for atmospheric CO2 while the gyre is in a quasi-steady state.
France Van Wambeke, Audrey Gimenez, Solange Duhamel, Cécile Dupouy, Dominique Lefevre, Mireille Pujo-Pay, and Thierry Moutin
Biogeosciences, 15, 2669–2689, https://doi.org/10.5194/bg-15-2669-2018, https://doi.org/10.5194/bg-15-2669-2018, 2018
Short summary
Short summary
The western tropical South Pacific Ocean has recently been shown to be a hotspot for biological nitrogen fixation. In this study, we examined the horizontal and vertical distribution of heterotrophic prokaryotic production alongside photosynthetic rates, nitrogen fixation rates and phosphate turnover times across the western tropical South Pacific Ocean, in order to relate these fluxes to bottom–up controls (related to nitrogen, phosphate and labile C availability).
Angela N. Knapp, Kelly M. McCabe, Olivier Grosso, Nathalie Leblond, Thierry Moutin, and Sophie Bonnet
Biogeosciences, 15, 2619–2628, https://doi.org/10.5194/bg-15-2619-2018, https://doi.org/10.5194/bg-15-2619-2018, 2018
Short summary
Short summary
The spatial distribution of biological N2 fixation fluxes to the ocean remains poorly constrained. Here we use nitrogen isotope budgets to identify significant N2 fixation inputs to the western tropical South Pacific (WTSP), where N2 fixation supports > 50 % of export production at stations proximal to iron sources. The significant N2 fixation inputs in the WTSP may offset nitrogen loss in the oxygen-deficient zones of the eastern tropical South Pacific.
Louise Rousselet, Alain de Verneil, Andrea M. Doglioli, Anne A. Petrenko, Solange Duhamel, Christophe Maes, and Bruno Blanke
Biogeosciences, 15, 2411–2431, https://doi.org/10.5194/bg-15-2411-2018, https://doi.org/10.5194/bg-15-2411-2018, 2018
Short summary
Short summary
The patterns of the large- and fine-scale surface circulation on biogeochemical and biological distributions are examined in the western tropical South Pacific (WTSP) in the context of the OUTPACE oceanographic cruise. The combined use of in situ and satellite data allows for the identification of water mass transport pathways and fine-scale structures, such as fronts, that drive surface distribution of tracers and microbial community structures.
Alain de Verneil, Louise Rousselet, Andrea M. Doglioli, Anne A. Petrenko, Christophe Maes, Pascale Bouruet-Aubertot, and Thierry Moutin
Biogeosciences, 15, 2125–2147, https://doi.org/10.5194/bg-15-2125-2018, https://doi.org/10.5194/bg-15-2125-2018, 2018
Short summary
Short summary
Oceanographic campaigns to measure biogeochemical processes popularly deploy drifters with onboard incubations to stay in a single body of water. Here, we aggregate physical data taken during such a cruise, OUTPACE, to independently test in a new approach whether the drifter really stayed in what can be considered a single biological or chemical environment. This study concludes that future campaigns would benefit from similar data collection and analysis to validate their sampling strategy.
Marcus Stenegren, Andrea Caputo, Carlo Berg, Sophie Bonnet, and Rachel A. Foster
Biogeosciences, 15, 1559–1578, https://doi.org/10.5194/bg-15-1559-2018, https://doi.org/10.5194/bg-15-1559-2018, 2018
Short summary
Short summary
We successfully performed quantitative PCR at sea. The qPCR data were procured within 3 h and used in decisions on further sampling on site. We designed and applied a new primer and probe set for quantifying the UCYN-A1 host and observed discrepancies between host and symbiont, which contradict previous studies. Lastly, we observed a clear vertical separation between a subsurface group (UCYN-A with hosts) and a surface group (remaining diazotrophs), mainly separated by temperature.
Pierre Marrec, Gérald Grégori, Andrea M. Doglioli, Mathilde Dugenne, Alice Della Penna, Nagib Bhairy, Thierry Cariou, Sandra Hélias Nunige, Soumaya Lahbib, Gilles Rougier, Thibaut Wagener, and Melilotus Thyssen
Biogeosciences, 15, 1579–1606, https://doi.org/10.5194/bg-15-1579-2018, https://doi.org/10.5194/bg-15-1579-2018, 2018
Short summary
Short summary
The objective of this study was to better understand the variability of the phytoplankton community structure in small physical structures at the surface of the ocean. After identifying such a structure in the Mediterranean Sea, we deployed cutting-edge physical and biological sensors in order to observe at a high frequency the dynamics of this structure. From these observations we described the variations of the phytoplankton community structure and how the physics controls this variability.
Alain Fumenia, Thierry Moutin, Sophie Bonnet, Mar Benavides, Anne Petrenko, Sandra Helias Nunige, and Christophe Maes
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-557, https://doi.org/10.5194/bg-2017-557, 2018
Revised manuscript not accepted
Short summary
Short summary
The Melanesian archipelago waters between 160° E and 170° W are characterized by a significant N2 fixation rates and an excess of particulate organic nitrogen compared to the canonical ratio of Redfield and a positive N*. We hypothesize that the southern branch of the subtropical gyre is probably the main vector of excess nitrogen transport in the thermocline waters showing an influence of nitrogen fixation occurring in the western tropical in a large part of the South Pacific.
Yangyang Lu, Zuozhu Wen, Dalin Shi, Mingming Chen, Yao Zhang, Sophie Bonnet, Yuhang Li, Jiwei Tian, and Shuh-Ji Kao
Biogeosciences, 15, 1–12, https://doi.org/10.5194/bg-15-1-2018, https://doi.org/10.5194/bg-15-1-2018, 2018
Short summary
Short summary
We investigated the light response of field Trichodesmium N2 fixation and net dissolved nitrogen release behavior. Our results suggest that N2 fixation was a function of light intensity, and the light requirement of Trichodesmium nitrogen fixation was high relative to its photosynthetic light demand. Meanwhile, light is a crucial parameter driving the physiological state of Trichodesmium, which subsequently determined the C / N metabolism and net dissolved nitrogen release.
Alain de Verneil, Louise Rousselet, Andrea M. Doglioli, Anne A. Petrenko, and Thierry Moutin
Biogeosciences, 14, 3471–3486, https://doi.org/10.5194/bg-14-3471-2017, https://doi.org/10.5194/bg-14-3471-2017, 2017
Short summary
Short summary
A surface summer plankton bloom in the western tropical South Pacific was sampled during the Oligotrophy to UlTra-oligotrophy PACific Experiment (OUTPACE) cruise. We characterize the bloom's properties and the circulation responsible for its evolution. Nitrogen fixation helped sustain the bloom, and larger-scale flows, rather than the smaller ones, explain its movements. Future studies of blooms in this region can make use of these findings to track the horizontal export of plankton production.
Thierry Moutin, Andrea Michelangelo Doglioli, Alain de Verneil, and Sophie Bonnet
Biogeosciences, 14, 3207–3220, https://doi.org/10.5194/bg-14-3207-2017, https://doi.org/10.5194/bg-14-3207-2017, 2017
Short summary
Short summary
The overall goal of OUTPACE was to obtain a successful representation of the interactions between planktonic organisms and the cycle of biogenic elements in the western tropical South Pacific Ocean across trophic and N2 fixation gradients. The international OUTPACE cruise took place between 18 February and 3 April 2015 aboard the RV L’Atalante and involved 60 scientists. The transect covered ~4 000 km from the western part of the Melanesian archipelago to the western boundary of the gyre.
Karine Leblanc, Véronique Cornet, Mathieu Caffin, Martine Rodier, Anne Desnues, Hugo Berthelot, Kendra Turk-Kubo, and Jules Heliou
Biogeosciences, 13, 5205–5219, https://doi.org/10.5194/bg-13-5205-2016, https://doi.org/10.5194/bg-13-5205-2016, 2016
Audrey Gimenez, Melika Baklouti, Sophie Bonnet, and Thierry Moutin
Biogeosciences, 13, 5103–5120, https://doi.org/10.5194/bg-13-5103-2016, https://doi.org/10.5194/bg-13-5103-2016, 2016
Short summary
Short summary
In the context of the VAHINE mesocosm experiment in the Nouméa lagoon (New Caledonia), a 1-D vertical biogeochemical mechanistic model was used together with the in situ experiment to complement our comprehension of the planktonic ecosystem dynamics and the main biogeochemical carbon, nitrogen and phosphate fluxes. The model also showed the fate of fixed N2 by providing, over time, the proportion of diazotroph-derived nitrogen (DDN) in each compartment (mineral and organic) of the model.
Angela N. Knapp, Sarah E. Fawcett, Alfredo Martínez-Garcia, Nathalie Leblond, Thierry Moutin, and Sophie Bonnet
Biogeosciences, 13, 4645–4657, https://doi.org/10.5194/bg-13-4645-2016, https://doi.org/10.5194/bg-13-4645-2016, 2016
Short summary
Short summary
The goal of this manuscript was to track the fate of newly fixed nitrogen (N) in large volume mesocosms in the coastal waters of New Caledonia. We used a N isotope ("δ15N") budget and found a shift in the δ15N of sinking particulate N over the 23-day experiment, indicating that nitrate supported export production at the beginning of the experiment, but that nitrogen fixation supported export at the end. We infer that nitrogen fixation supported export production by a release of dissolved N.
Sophie Bonnet, Melika Baklouti, Audrey Gimenez, Hugo Berthelot, and Ilana Berman-Frank
Biogeosciences, 13, 4461–4479, https://doi.org/10.5194/bg-13-4461-2016, https://doi.org/10.5194/bg-13-4461-2016, 2016
Dina Spungin, Ulrike Pfreundt, Hugo Berthelot, Sophie Bonnet, Dina AlRoumi, Frank Natale, Wolfgang R. Hess, Kay D. Bidle, and Ilana Berman-Frank
Biogeosciences, 13, 4187–4203, https://doi.org/10.5194/bg-13-4187-2016, https://doi.org/10.5194/bg-13-4187-2016, 2016
Short summary
Short summary
The marine cyanobacterium Trichodesmium spp. forms massive blooms important to carbon and nitrogen cycling in the oceans that often collapse abruptly. We investigated a Trichodesmium bloom in the lagoon waters of New Caledonia to specifically elucidate the cellular processes mediating the bloom decline. We demonstrate physiological, biochemical, and genetic evidence for nutrient and oxidative stress that induced a genetically controlled programmed cell death (PCD) pathway leading to bloom demise.
Ulrike Pfreundt, Dina Spungin, Sophie Bonnet, Ilana Berman-Frank, and Wolfgang R. Hess
Biogeosciences, 13, 4135–4149, https://doi.org/10.5194/bg-13-4135-2016, https://doi.org/10.5194/bg-13-4135-2016, 2016
Short summary
Short summary
The VAHINE experiment in the New Caledonia lagoon (SW Pacific) targeted the dynamics of nutrient pools and fluxes, N2 fixation, and the composition and productivity of the microbial communities. To connect this information to the actual activities of diverse microbial taxa, we present the analysis of the community-wide gene expression for 23 days. The results from this experiment provide insight into the microbial activities in a low-nutrient, low-chlorophyll ecosystem and within a mesocosm.
Hugo Berthelot, Sophie Bonnet, Olivier Grosso, Véronique Cornet, and Aude Barani
Biogeosciences, 13, 4005–4021, https://doi.org/10.5194/bg-13-4005-2016, https://doi.org/10.5194/bg-13-4005-2016, 2016
Ilana Berman-Frank, Dina Spungin, Eyal Rahav, France Van Wambeke, Kendra Turk-Kubo, and Thierry Moutin
Biogeosciences, 13, 3793–3805, https://doi.org/10.5194/bg-13-3793-2016, https://doi.org/10.5194/bg-13-3793-2016, 2016
Short summary
Short summary
In the marine environment, sticky sugar-containing gels, termed transparent exopolymeric particles (TEP), are produced from biological sources and physical and chemical processes. These compounds are essential vectors enhancing downward flow of organic matter and its storage at depth. Spatial and temporal dynamics of TEPs were followed for 23 days during the VAHINE mesocosm experiment that investigated the fate of nitrogen and carbon derived from organisms fixing atmospheric N2 (diazotrophs).
France Van Wambeke, Ulrike Pfreundt, Aude Barani, Hugo Berthelot, Thierry Moutin, Martine Rodier, Wolfgang R. Hess, and Sophie Bonnet
Biogeosciences, 13, 3187–3202, https://doi.org/10.5194/bg-13-3187-2016, https://doi.org/10.5194/bg-13-3187-2016, 2016
Short summary
Short summary
The phytoplankton is at the base of the plankton food web in large parts of oceanic "deserts" such as the South Pacific Ocean, where nitrogen sources limit activity. Mesocosms were fertilized with phosphorus to stimulate diazotrophy (atmospheric N2 fixation). Mostly diazotroph-derived nitrogen fuelled the heterotrophic bacterial community through indirect processes generating dissolved organic matter and detritus, such as mortality, lysis and grazing of both diazotrophs and non-diazotrophs.
Brian P. V. Hunt, Sophie Bonnet, Hugo Berthelot, Brandon J. Conroy, Rachel A. Foster, and Marc Pagano
Biogeosciences, 13, 3131–3145, https://doi.org/10.5194/bg-13-3131-2016, https://doi.org/10.5194/bg-13-3131-2016, 2016
Short summary
Short summary
Biological nitrogen (N) fixation is an important source of N for food webs in tropical and subtropical oceans. However, uptake pathways remain poorly understood. This study found that fixed N contributed a third of total zooplankton N in the New Caledonia lagoon. Fixed N reached the zooplankton through 1) direct grazing on N fixers and 2) grazing on phytoplankton that had taken up N released by fixers. We report the first record of direct zooplankton grazing on the unicellular N fixer UCYN-C.
Sophie Bonnet, Thierry Moutin, Martine Rodier, Jean-Michel Grisoni, Francis Louis, Eric Folcher, Bertrand Bourgeois, Jean-Michel Boré, and Armelle Renaud
Biogeosciences, 13, 2803–2814, https://doi.org/10.5194/bg-13-2803-2016, https://doi.org/10.5194/bg-13-2803-2016, 2016
Short summary
Short summary
e main goal of the VAHINE project was to study the fate of N2 fixation in the ocean. Three large-volume (~ 50 m3) mesocosms were deployed in a tropical oligotrophic ecosystem (the New Caledonia lagoon, south-eastern Pacific). This introductory paper describes the scientific objectives of the project in detail as well as the implementation plan: the mesocosm description and deployment, the selection of the study site, and the logistical and sampling strategy.
Sophie Bonnet, Hugo Berthelot, Kendra Turk-Kubo, Sarah Fawcett, Eyal Rahav, Stéphane L'Helguen, and Ilana Berman-Frank
Biogeosciences, 13, 2653–2673, https://doi.org/10.5194/bg-13-2653-2016, https://doi.org/10.5194/bg-13-2653-2016, 2016
Short summary
Short summary
N2 fixation rates were measured daily in ~ 50 m3 mesocosms deployed in New Caledonia to investigate the high-frequency dynamics of diazotrophy and the fate of diazotroph-derived nitrogen (DDN) oligotrophic ecosystems. ~ 10 % of UCYN-C from the water column were exported daily to the traps, representing as much as 22.4 ± 5.5 % of the total POC exported at the height of the UCYN-C bloom. 16 ± 6 % of the DDN was released to the dissolved pool and 21 ± 4 % was transferred to non-diazotrophic plankton.
Ulrike Pfreundt, France Van Wambeke, Mathieu Caffin, Sophie Bonnet, and Wolfgang R. Hess
Biogeosciences, 13, 2319–2337, https://doi.org/10.5194/bg-13-2319-2016, https://doi.org/10.5194/bg-13-2319-2016, 2016
Short summary
Short summary
The Southwest Pacific has one of the highest N2 fixation rates in the global ocean, yet information is scarce on the bacterioplankton interrelationships. We detected high microbial diversity in the New Caledonia lagoon and inside a 50 000 L experimental enclosure of the same water mass over 3 weeks and give evidence for previously unknown niche partitioning. Phosphate fertilization promoted the growth of efficient N2 fixing cyanobacteria triggering the growth of most heterotrophic bacteria.
K. A. Turk-Kubo, I. E. Frank, M. E. Hogan, A. Desnues, S. Bonnet, and J. P. Zehr
Biogeosciences, 12, 7435–7452, https://doi.org/10.5194/bg-12-7435-2015, https://doi.org/10.5194/bg-12-7435-2015, 2015
Short summary
Short summary
-A shift from diatom-associated diazotrophs (DDAs) to unicellular cyanobacterial group C (UCYN-C) in response to DIP fertilization was captured in a large-scale mesocosm experiment in the Noumea lagoon (NL), a low-nutrient low-chlorophyll coastal environment. -First report of in situ net growth and mortality rates for unicellular diazotrophs UCYN-A2, and UCYN-C. -First quantitative abundance data for diazotrophs in NL indicate that DDAs and UCYN-A1/A2 may be important N2 fixers in this region.
A. Guyennon, M. Baklouti, F. Diaz, J. Palmieri, J. Beuvier, C. Lebaupin-Brossier, T. Arsouze, K. Béranger, J.-C. Dutay, and T. Moutin
Biogeosciences, 12, 7025–7046, https://doi.org/10.5194/bg-12-7025-2015, https://doi.org/10.5194/bg-12-7025-2015, 2015
Short summary
Short summary
Dissolved organic carbon (DOC) has already been identified as a potentially significant source of carbon export in the Mediterranean Sea, though in situ export estimations are scarce. This work provides a thorough analysis at basin scale of carbon export with the coupled model NEMO-MED12/Eco3M-MED model. The seasonality and the processes of particulate and dissolved carbon production are also investigated. DOC export appears to be dominant in most regions, especially in the eastern basin.
A. N. Schwier, C. Rose, E. Asmi, A. M. Ebling, W. M. Landing, S. Marro, M.-L. Pedrotti, A. Sallon, F. Iuculano, S. Agusti, A. Tsiola, P. Pitta, J. Louis, C. Guieu, F. Gazeau, and K. Sellegri
Atmos. Chem. Phys., 15, 7961–7976, https://doi.org/10.5194/acp-15-7961-2015, https://doi.org/10.5194/acp-15-7961-2015, 2015
Short summary
Short summary
The effect of ocean acidification and changing water conditions on primary (and secondary) marine aerosol emissions is not well understood on a regional or a global scale. To investigate this effect, we deployed mesocosms in the Mediterranean Sea for several weeks during both winter pre-bloom and summer oligotrophic conditions and subjected them to various levels of CO2. We observed larger effects due to the differences between a pre-bloom and oligotrophic environment than due to CO2 levels.
H. Berthelot, T. Moutin, S. L'Helguen, K. Leblanc, S. Hélias, O. Grosso, N. Leblond, B. Charrière, and S. Bonnet
Biogeosciences, 12, 4099–4112, https://doi.org/10.5194/bg-12-4099-2015, https://doi.org/10.5194/bg-12-4099-2015, 2015
A. Talarmin, F. Van Wambeke, P. Lebaron, and T. Moutin
Biogeosciences, 12, 1237–1247, https://doi.org/10.5194/bg-12-1237-2015, https://doi.org/10.5194/bg-12-1237-2015, 2015
Short summary
Short summary
Along a transect in the warm nutrient-depleted Mediterranean Sea, we found that microorganisms shared phosphate resources by using different uptake strategies. Heterotrophic prokaryotes dominated phosphate uptake in the upper layers while cyanobacteria dominated uptake fluxes around the deep chlorophyll maximum depth. Synechococcus seemed well equipped to respond to pulses of phosphate, whereas Prochlorococcus and heterotrophs were more adapted to very low concentrations.
E. Pulido-Villena, A.-C. Baudoux, I. Obernosterer, M. Landa, J. Caparros, P. Catala, C. Georges, J. Harmand, and C. Guieu
Biogeosciences, 11, 5607–5619, https://doi.org/10.5194/bg-11-5607-2014, https://doi.org/10.5194/bg-11-5607-2014, 2014
C. Guieu, C. Ridame, E. Pulido-Villena, M. Bressac, K. Desboeufs, and F. Dulac
Biogeosciences, 11, 5621–5635, https://doi.org/10.5194/bg-11-5621-2014, https://doi.org/10.5194/bg-11-5621-2014, 2014
K. Desboeufs, N. Leblond, T. Wagener, E. Bon Nguyen, and C. Guieu
Biogeosciences, 11, 5581–5594, https://doi.org/10.5194/bg-11-5581-2014, https://doi.org/10.5194/bg-11-5581-2014, 2014
C. Ridame, J. Dekaezemacker, C. Guieu, S. Bonnet, S. L'Helguen, and F. Malien
Biogeosciences, 11, 4783–4800, https://doi.org/10.5194/bg-11-4783-2014, https://doi.org/10.5194/bg-11-4783-2014, 2014
M. Bressac, C. Guieu, D. Doxaran, F. Bourrin, K. Desboeufs, N. Leblond, and C. Ridame
Biogeosciences, 11, 1007–1020, https://doi.org/10.5194/bg-11-1007-2014, https://doi.org/10.5194/bg-11-1007-2014, 2014
C. Guieu, F. Dulac, C. Ridame, and P. Pondaven
Biogeosciences, 11, 425–442, https://doi.org/10.5194/bg-11-425-2014, https://doi.org/10.5194/bg-11-425-2014, 2014
C. Ridame, C. Guieu, and S. L'Helguen
Biogeosciences, 10, 7333–7346, https://doi.org/10.5194/bg-10-7333-2013, https://doi.org/10.5194/bg-10-7333-2013, 2013
V. Giovagnetti, C. Brunet, F. Conversano, F. Tramontano, I. Obernosterer, C. Ridame, and C. Guieu
Biogeosciences, 10, 2973–2991, https://doi.org/10.5194/bg-10-2973-2013, https://doi.org/10.5194/bg-10-2973-2013, 2013
K. Wuttig, T. Wagener, M. Bressac, A. Dammshäuser, P. Streu, C. Guieu, and P. L. Croot
Biogeosciences, 10, 2583–2600, https://doi.org/10.5194/bg-10-2583-2013, https://doi.org/10.5194/bg-10-2583-2013, 2013
Related subject area
Biogeochemistry: Open Ocean
Assessing the impact of CO2-equilibrated ocean alkalinity enhancement on microbial metabolic rates in an oligotrophic system
Phosphomonoesterase and phosphodiesterase activities in the eastern Mediterranean in two contrasting seasonal situations
Net primary production annual maxima in the North Atlantic projected to shift in the 21st century
Testing the influence of light on nitrite cycling in the eastern tropical North Pacific
Loss of nitrogen via anaerobic ammonium oxidation (anammox) in the California Current system during the late Quaternary
Technical note: Assessment of float pH data quality control methods – a case study in the subpolar northwest Atlantic Ocean
Effects of grain size and seawater salinity on magnesium hydroxide dissolution and secondary calcium carbonate precipitation kinetics: implications for ocean alkalinity enhancement
Linking northeastern North Pacific oxygen changes to upstream surface outcrop variations
Short-term response of Emiliania huxleyi growth and morphology to abrupt salinity stress
Underestimation of multi-decadal global O2 loss due to an optimal interpolation method
Reviews and syntheses: expanding the global coverage of gross primary production and net community production measurements using Biogeochemical-Argo floats
Characteristics of surface physical and biogeochemical parameters within mesoscale eddies in the Southern Ocean
Climatic Controls on Metabolic Constraints in the Ocean
Seasonal dynamics and annual budget of dissolved inorganic carbon in the northwestern Mediterranean deep-convection region
The fingerprint of climate variability on the surface ocean cycling of iron and its isotopes
Reconstructing the ocean's mesopelagic zone carbon budget: sensitivity and estimation of parameters associated with prokaryotic remineralization
Evolution of oxygen and stratification in the North Pacific Ocean in CMIP6 Earth System Models
Seasonal cycles of biogeochemical fluxes in the Scotia Sea, Southern Ocean: a stable isotope approach
Biological impact of ocean alkalinity enhancement of magnesium hydroxide on marine microalgae using bioassays simulating ship-based dispersion
Absence of photophysiological response to iron addition in autumn phytoplankton in the Antarctic sea-ice zone
Optimal parameters for the ocean's nutrient, carbon, and oxygen cycles compensate for circulation biases but replumb the biological pump
Importance of multiple sources of iron for the upper-ocean biogeochemistry over the northern Indian Ocean
Exploring the role of different data types and timescales in the quality of marine biogeochemical model calibration
All about nitrite: exploring nitrite sources and sinks in the eastern tropical North Pacific oxygen minimum zone
Fossil coccolith morphological attributes as a new proxy for deep ocean carbonate chemistry
Reconstructing ocean carbon storage with CMIP6 Earth system models and synthetic Argo observations
Using machine learning and Biogeochemical-Argo (BGC-Argo) floats to assess biogeochemical models and optimize observing system design
The representation of alkalinity and the carbonate pump from CMIP5 to CMIP6 Earth system models and implications for the carbon cycle
Model estimates of metazoans' contributions to the biological carbon pump
Tracing differences in iron supply to the Mid-Atlantic Ridge valley between hydrothermal vent sites: implications for the addition of iron to the deep ocean
Nitrite cycling in the primary nitrite maxima of the eastern tropical North Pacific
Hotspots and drivers of compound marine heatwaves and low net primary production extremes
Ecosystem impacts of marine heat waves in the northeast Pacific
Tracing the role of Arctic shelf processes in Si and N cycling and export through the Fram Strait: insights from combined silicon and nitrate isotopes
Controls on the relative abundances and rates of nitrifying microorganisms in the ocean
The response of diazotrophs to nutrient amendment in the South China Sea and western North Pacific
Influence of GEOTRACES data distribution and misfit function choice on objective parameter retrieval in a marine zinc cycle model
Physiological flexibility of phytoplankton impacts modelled chlorophyll and primary production across the North Pacific Ocean
Observation-constrained estimates of the global ocean carbon sink from Earth system models
Early winter barium excess in the southern Indian Ocean as an annual remineralisation proxy (GEOTRACES GIPr07 cruise)
Controlling factors on the global distribution of a representative marine non-cyanobacterial diazotroph phylotype (Gamma A)
Summer trends and drivers of sea surface fCO2 and pH changes observed in the southern Indian Ocean over the last two decades (1998–2019)
Global nutrient cycling by commercially targeted marine fish
Major processes of the dissolved cobalt cycle in the North and equatorial Pacific Ocean
The impact of the South-East Madagascar Bloom on the oceanic CO2 sink
Nitrite regeneration in the oligotrophic Atlantic Ocean
Bridging the gaps between particulate backscattering measurements and modeled particulate organic carbon in the ocean
Biological production in two contrasted regions of the Mediterranean Sea during the oligotrophic period: an estimate based on the diel cycle of optical properties measured by BioGeoChemical-Argo profiling floats
Acidification of the Nordic Seas
Reconstruction of global surface ocean pCO2 using region-specific predictors based on a stepwise FFNN regression algorithm
Laura Marín-Samper, Javier Arístegui, Nauzet Hernández-Hernández, Joaquín Ortiz, Stephen D. Archer, Andrea Ludwig, and Ulf Riebesell
Biogeosciences, 21, 2859–2876, https://doi.org/10.5194/bg-21-2859-2024, https://doi.org/10.5194/bg-21-2859-2024, 2024
Short summary
Short summary
Our planet is facing a climate crisis. Scientists are working on innovative solutions that will aid in capturing the hard to abate emissions before it is too late. Exciting research reveals that ocean alkalinity enhancement, a key climate change mitigation strategy, does not harm phytoplankton, the cornerstone of marine ecosystems. Through meticulous study, we may have uncovered a positive relationship: up to a specific limit, enhancing ocean alkalinity boosts photosynthesis by certain species.
France Van Wambeke, Pascal Conan, Mireille Pujo-Pay, Vincent Taillandier, Olivier Crispi, Alexandra Pavlidou, Sandra Nunige, Morgane Didry, Christophe Salmeron, and Elvira Pulido-Villena
Biogeosciences, 21, 2621–2640, https://doi.org/10.5194/bg-21-2621-2024, https://doi.org/10.5194/bg-21-2621-2024, 2024
Short summary
Short summary
Phosphomonoesterase (PME) and phosphodiesterase (PDE) activities over the epipelagic zone are described in the eastern Mediterranean Sea in winter and autumn. The types of concentration kinetics obtained for PDE (saturation at 50 µM, high Km, high turnover times) compared to those of PME (saturation at 1 µM, low Km, low turnover times) are discussed in regard to the possible inequal distribution of PDE and PME in the size continuum of organic material and accessibility to phosphodiesters.
Jenny Hieronymus, Magnus Hieronymus, Matthias Gröger, Jörg Schwinger, Raffaele Bernadello, Etienne Tourigny, Valentina Sicardi, Itzel Ruvalcaba Baroni, and Klaus Wyser
Biogeosciences, 21, 2189–2206, https://doi.org/10.5194/bg-21-2189-2024, https://doi.org/10.5194/bg-21-2189-2024, 2024
Short summary
Short summary
The timing of the net primary production annual maxima in the North Atlantic in the period 1750–2100 is investigated using two Earth system models and the high-emissions scenario SSP5-8.5. It is found that, for most of the region, the annual maxima occur progressively earlier, with the most change occurring after the year 2000. Shifts in the seasonality of the primary production may impact the entire ecosystem, which highlights the need for long-term monitoring campaigns in this area.
Nicole M. Travis, Colette L. Kelly, and Karen L. Casciotti
Biogeosciences, 21, 1985–2004, https://doi.org/10.5194/bg-21-1985-2024, https://doi.org/10.5194/bg-21-1985-2024, 2024
Short summary
Short summary
We conducted experimental manipulations of light level on microbial communities from the primary nitrite maximum. Overall, while individual microbial processes have different directions and magnitudes in their response to increasing light, the net community response is a decline in nitrite production with increasing light. We conclude that while increased light may decrease net nitrite production, high-light conditions alone do not exclude nitrification from occurring in the surface ocean.
Zoë Rebecca van Kemenade, Zeynep Erdem, Ellen Christine Hopmans, Jaap Smede Sinninghe Damsté, and Darci Rush
Biogeosciences, 21, 1517–1532, https://doi.org/10.5194/bg-21-1517-2024, https://doi.org/10.5194/bg-21-1517-2024, 2024
Short summary
Short summary
The California Current system (CCS) hosts the eastern subtropical North Pacific oxygen minimum zone (ESTNP OMZ). This study shows anaerobic ammonium oxidizing (anammox) bacteria cause a loss of bioavailable nitrogen (N) in the ESTNP OMZ throughout the late Quaternary. Anammox occurred during both glacial and interglacial periods and was driven by the supply of organic matter and changes in ocean currents. These findings may have important consequences for biogeochemical models of the CCS.
Cathy Wimart-Rousseau, Tobias Steinhoff, Birgit Klein, Henry Bittig, and Arne Körtzinger
Biogeosciences, 21, 1191–1211, https://doi.org/10.5194/bg-21-1191-2024, https://doi.org/10.5194/bg-21-1191-2024, 2024
Short summary
Short summary
The marine CO2 system can be measured independently and continuously by BGC-Argo floats since numerous pH sensors have been developed to suit these autonomous measurements platforms. By applying the Argo correction routines to float pH data acquired in the subpolar North Atlantic Ocean, we report the uncertainty and lack of objective criteria associated with the choice of the reference method as well the reference depth for the pH correction.
Charly Andre Moras, Tyler Cyronak, Lennart Thomas Bach, Renaud Joannes-Boyau, and Kai Georg Schulz
EGUsphere, https://doi.org/10.5194/egusphere-2024-645, https://doi.org/10.5194/egusphere-2024-645, 2024
Short summary
Short summary
We investigate the effects of mineral grain size and seawater salinity on magnesium hydroxide dissolution and calcium carbonate precipitation kinetics for ocean alkalinity enhancement. Salinity did not affect the dissolution, but calcium carbonate formed earlier at lower salinities due to the lower magnesium and dissolved organic carbon concentrations. Smaller grain size dissolved faster, but calcium carbonate precipitated earlier, suggesting that medium grain size is optimum for both kinetics.
Sabine Mecking and Kyla Drushka
Biogeosciences, 21, 1117–1133, https://doi.org/10.5194/bg-21-1117-2024, https://doi.org/10.5194/bg-21-1117-2024, 2024
Short summary
Short summary
This study investigates whether northeastern North Pacific oxygen changes may be caused by surface density changes in the northwest as water moves along density horizons from the surface into the subsurface ocean. A correlation is found with a lag that about matches the travel time of water from the northwest to the northeast. Salinity is the main driver causing decadal changes in surface density, whereas salinity and temperature contribute about equally to long-term declining density trends.
Rosie M. Sheward, Christina Gebühr, Jörg Bollmann, and Jens O. Herrle
EGUsphere, https://doi.org/10.5194/egusphere-2024-349, https://doi.org/10.5194/egusphere-2024-349, 2024
Short summary
Short summary
How quickly do marine microorganisms respond to salinity stress? Our experiments with the calcifying marine plankton Emiliania huxleyi show that growth and cell morphology responded to salinity stress within as little as 24–48 hours, demonstrating that morphology and calcification is sensitive to salinity over a range of timescales. Our results have implications for understanding the short-term role of E. huxleyi in biogeochemical cycles and size-based paleoproxies for salinity.
Takamitsu Ito, Hernan E. Garcia, Zhankun Wang, Shoshiro Minobe, Matthew C. Long, Just Cebrian, James Reagan, Tim Boyer, Christopher Paver, Courtney Bouchard, Yohei Takano, Seth Bushinsky, Ahron Cervania, and Curtis A. Deutsch
Biogeosciences, 21, 747–759, https://doi.org/10.5194/bg-21-747-2024, https://doi.org/10.5194/bg-21-747-2024, 2024
Short summary
Short summary
This study aims to estimate how much oceanic oxygen has been lost and its uncertainties. One major source of uncertainty comes from the statistical gap-filling methods. Outputs from Earth system models are used to generate synthetic observations where oxygen data are extracted from the model output at the location and time of historical oceanographic cruises. Reconstructed oxygen trend is approximately two-thirds of the true trend.
Robert W. Izett, Katja Fennel, Adam C. Stoer, and David P. Nicholson
Biogeosciences, 21, 13–47, https://doi.org/10.5194/bg-21-13-2024, https://doi.org/10.5194/bg-21-13-2024, 2024
Short summary
Short summary
This paper provides an overview of the capacity to expand the global coverage of marine primary production estimates using autonomous ocean-going instruments, called Biogeochemical-Argo floats. We review existing approaches to quantifying primary production using floats, provide examples of the current implementation of the methods, and offer insights into how they can be better exploited. This paper is timely, given the ongoing expansion of the Biogeochemical-Argo array.
Qian Liu, Yingjie Liu, and Xiaofeng Li
Biogeosciences, 20, 4857–4874, https://doi.org/10.5194/bg-20-4857-2023, https://doi.org/10.5194/bg-20-4857-2023, 2023
Short summary
Short summary
In the Southern Ocean, abundant eddies behave opposite to our expectations. That is, anticyclonic (cyclonic) eddies are cold (warm). By investigating the variations of physical and biochemical parameters in eddies, we find that abnormal eddies have unique and significant effects on modulating the parameters. This study fills a gap in understanding the effects of abnormal eddies on physical and biochemical parameters in the Southern Ocean.
Precious Mongwe, Matthew Long, Takamitsu Ito, Curtis Deutsch, and Yeray Santana-Falcón
EGUsphere, https://doi.org/10.5194/egusphere-2023-2822, https://doi.org/10.5194/egusphere-2023-2822, 2023
Short summary
Short summary
We use a collection of measurements that captures the physiological sensitivity of organisms to temperature and oxygen, and a model to investigate how natural climate variations and climate warming will impact the ability of marine heterotrophic marine organisms to support habitat in the future. We find that warming and the related loss of marine dissolved oxygen over the next several decades will reduce the volume of ocean habitat, and increasing vulnerability to temperature-oxygen extremes.
Caroline Ulses, Claude Estournel, Patrick Marsaleix, Karline Soetaert, Marine Fourrier, Laurent Coppola, Dominique Lefèvre, Franck Touratier, Catherine Goyet, Véronique Guglielmi, Fayçal Kessouri, Pierre Testor, and Xavier Durrieu de Madron
Biogeosciences, 20, 4683–4710, https://doi.org/10.5194/bg-20-4683-2023, https://doi.org/10.5194/bg-20-4683-2023, 2023
Short summary
Short summary
Deep convection plays a key role in the circulation, thermodynamics, and biogeochemical cycles in the Mediterranean Sea, considered to be a hotspot of biodiversity and climate change. In this study, we investigate the seasonal and annual budget of dissolved inorganic carbon in the deep-convection area of the northwestern Mediterranean Sea.
Daniela König and Alessandro Tagliabue
Biogeosciences, 20, 4197–4212, https://doi.org/10.5194/bg-20-4197-2023, https://doi.org/10.5194/bg-20-4197-2023, 2023
Short summary
Short summary
Using model simulations, we show that natural and anthropogenic changes in the global climate leave a distinct fingerprint in the isotopic signatures of iron in the surface ocean. We find that these climate effects on iron isotopes are often caused by the redistribution of iron from different external sources to the ocean, due to changes in ocean currents, and by changes in algal growth, which take up iron. Thus, isotopes may help detect climate-induced changes in iron supply and algal uptake.
Chloé Baumas, Robin Fuchs, Marc Garel, Jean-Christophe Poggiale, Laurent Memery, Frédéric A. C. Le Moigne, and Christian Tamburini
Biogeosciences, 20, 4165–4182, https://doi.org/10.5194/bg-20-4165-2023, https://doi.org/10.5194/bg-20-4165-2023, 2023
Short summary
Short summary
Through the sink of particles in the ocean, carbon (C) is exported and sequestered when reaching 1000 m. Attempts to quantify C exported vs. C consumed by heterotrophs have increased. Yet most of the conducted estimations have led to C demands several times higher than C export. The choice of parameters greatly impacts the results. As theses parameters are overlooked, non-accurate values are often used. In this study we show that C budgets can be well balanced when using appropriate values.
Lyuba Novi, Annalisa Bracco, Takamitsu Ito, and Yohei Takano
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-129, https://doi.org/10.5194/bg-2023-129, 2023
Revised manuscript accepted for BG
Short summary
Short summary
We explored the relationship between oxygen and stratification in the North Pacific Ocean, using a combination of data mining and machine learning. We used isopycnic potential vorticity (IPV) as an indicator to quantify ocean ventilation and we analyzed its predictability, a strong O2-IPV connection and predictability for IPV in the tropical Pacific. This open new routes to monitor ocean O2 through few observational sites co-located with more abundant IPV measurements in the tropical Pacific.
Anna Belcher, Sian F. Henley, Katharine Hendry, Marianne Wootton, Lisa Friberg, Ursula Dallman, Tong Wang, Christopher Coath, and Clara Manno
Biogeosciences, 20, 3573–3591, https://doi.org/10.5194/bg-20-3573-2023, https://doi.org/10.5194/bg-20-3573-2023, 2023
Short summary
Short summary
The oceans play a crucial role in the uptake of atmospheric carbon dioxide, particularly the Southern Ocean. The biological pumping of carbon from the surface to the deep ocean is key to this. Using sediment trap samples from the Scotia Sea, we examine biogeochemical fluxes of carbon, nitrogen, and biogenic silica and their stable isotope compositions. We find phytoplankton community structure and physically mediated processes are important controls on particulate fluxes to the deep ocean.
Stephanie Delacroix, Tor Jensen Nystuen, Erik Höglund, and Andrew L. King
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-138, https://doi.org/10.5194/bg-2023-138, 2023
Revised manuscript accepted for BG
Short summary
Short summary
The addition of alkaline minerals into the oceans might reduce the excessive anthropogenic CO2 emissions. Magnesium hydroxide can be added in large amount because of its low seawater solubility without reaching harmful pH levels. The toxicity effect results of magnesium hydroxide, by simulating expected concentrations from a ships’ dispersion scenario, demonstrated low impacts on both sensitive and local assemblages of marine microalgae when compared to calcium hydroxide and sodium hydroxide.
Asmita Singh, Susanne Fietz, Sandy J. Thomalla, Nicolas Sanchez, Murat V. Ardelan, Sébastien Moreau, Hanna M. Kauko, Agneta Fransson, Melissa Chierici, Saumik Samanta, Thato N. Mtshali, Alakendra N. Roychoudhury, and Thomas J. Ryan-Keogh
Biogeosciences, 20, 3073–3091, https://doi.org/10.5194/bg-20-3073-2023, https://doi.org/10.5194/bg-20-3073-2023, 2023
Short summary
Short summary
Despite the scarcity of iron in the Southern Ocean, seasonal blooms occur due to changes in nutrient and light availability. Surprisingly, during an autumn bloom in the Antarctic sea-ice zone, the results from incubation experiments showed no significant photophysiological response of phytoplankton to iron addition. This suggests that ambient iron concentrations were sufficient, challenging the notion of iron deficiency in the Southern Ocean through extended iron-replete post-bloom conditions.
Benoît Pasquier, Mark Holzer, Matthew A. Chamberlain, Richard J. Matear, Nathaniel L. Bindoff, and François W. Primeau
Biogeosciences, 20, 2985–3009, https://doi.org/10.5194/bg-20-2985-2023, https://doi.org/10.5194/bg-20-2985-2023, 2023
Short summary
Short summary
Modeling the ocean's carbon and oxygen cycles accurately is challenging. Parameter optimization improves the fit to observed tracers but can introduce artifacts in the biological pump. Organic-matter production and subsurface remineralization rates adjust to compensate for circulation biases, changing the pathways and timescales with which nutrients return to the surface. Circulation biases can thus strongly alter the system’s response to ecological change, even when parameters are optimized.
Priyanka Banerjee
Biogeosciences, 20, 2613–2643, https://doi.org/10.5194/bg-20-2613-2023, https://doi.org/10.5194/bg-20-2613-2023, 2023
Short summary
Short summary
This study shows that atmospheric deposition is the most important source of iron to the upper northern Indian Ocean for phytoplankton growth. This is followed by iron from continental-shelf sediment. Phytoplankton increase following iron addition is possible only with high background levels of nitrate. Vertical mixing is the most important physical process supplying iron to the upper ocean in this region throughout the year. The importance of ocean currents in supplying iron varies seasonally.
Iris Kriest, Julia Getzlaff, Angela Landolfi, Volkmar Sauerland, Markus Schartau, and Andreas Oschlies
Biogeosciences, 20, 2645–2669, https://doi.org/10.5194/bg-20-2645-2023, https://doi.org/10.5194/bg-20-2645-2023, 2023
Short summary
Short summary
Global biogeochemical ocean models are often subjectively assessed and tuned against observations. We applied different strategies to calibrate a global model against observations. Although the calibrated models show similar tracer distributions at the surface, they differ in global biogeochemical fluxes, especially in global particle flux. Simulated global volume of oxygen minimum zones varies strongly with calibration strategy and over time, rendering its temporal extrapolation difficult.
John C. Tracey, Andrew R. Babbin, Elizabeth Wallace, Xin Sun, Katherine L. DuRussel, Claudia Frey, Donald E. Martocello III, Tyler Tamasi, Sergey Oleynik, and Bess B. Ward
Biogeosciences, 20, 2499–2523, https://doi.org/10.5194/bg-20-2499-2023, https://doi.org/10.5194/bg-20-2499-2023, 2023
Short summary
Short summary
Nitrogen (N) is essential for life; thus, its availability plays a key role in determining marine productivity. Using incubations of seawater spiked with a rare form of N measurable on a mass spectrometer, we quantified microbial pathways that determine marine N availability. The results show that pathways that recycle N have higher rates than those that result in its loss from biomass and present new evidence for anaerobic nitrite oxidation, a process long thought to be strictly aerobic.
Amanda Gerotto, Hongrui Zhang, Renata Hanae Nagai, Heather M. Stoll, Rubens César Lopes Figueira, Chuanlian Liu, and Iván Hernández-Almeida
Biogeosciences, 20, 1725–1739, https://doi.org/10.5194/bg-20-1725-2023, https://doi.org/10.5194/bg-20-1725-2023, 2023
Short summary
Short summary
Based on the analysis of the response of coccolithophores’ morphological attributes in a laboratory dissolution experiment and surface sediment samples from the South China Sea, we proposed that the thickness shape (ks) factor of fossil coccoliths together with the normalized ks variation, which is the ratio of the standard deviation of ks (σ) over the mean ks (σ/ks), is a robust and novel proxy to reconstruct past changes in deep ocean carbon chemistry.
Katherine E. Turner, Doug M. Smith, Anna Katavouta, and Richard G. Williams
Biogeosciences, 20, 1671–1690, https://doi.org/10.5194/bg-20-1671-2023, https://doi.org/10.5194/bg-20-1671-2023, 2023
Short summary
Short summary
We present a new method for reconstructing ocean carbon using climate models and temperature and salinity observations. To test this method, we reconstruct modelled carbon using synthetic observations consistent with current sampling programmes. Sensitivity tests show skill in reconstructing carbon trends and variability within the upper 2000 m. Our results indicate that this method can be used for a new global estimate for ocean carbon content.
Alexandre Mignot, Hervé Claustre, Gianpiero Cossarini, Fabrizio D'Ortenzio, Elodie Gutknecht, Julien Lamouroux, Paolo Lazzari, Coralie Perruche, Stefano Salon, Raphaëlle Sauzède, Vincent Taillandier, and Anna Teruzzi
Biogeosciences, 20, 1405–1422, https://doi.org/10.5194/bg-20-1405-2023, https://doi.org/10.5194/bg-20-1405-2023, 2023
Short summary
Short summary
Numerical models of ocean biogeochemistry are becoming a major tool to detect and predict the impact of climate change on marine resources and monitor ocean health. Here, we demonstrate the use of the global array of BGC-Argo floats for the assessment of biogeochemical models. We first detail the handling of the BGC-Argo data set for model assessment purposes. We then present 23 assessment metrics to quantify the consistency of BGC model simulations with respect to BGC-Argo data.
Alban Planchat, Lester Kwiatkowski, Laurent Bopp, Olivier Torres, James R. Christian, Momme Butenschön, Tomas Lovato, Roland Séférian, Matthew A. Chamberlain, Olivier Aumont, Michio Watanabe, Akitomo Yamamoto, Andrew Yool, Tatiana Ilyina, Hiroyuki Tsujino, Kristen M. Krumhardt, Jörg Schwinger, Jerry Tjiputra, John P. Dunne, and Charles Stock
Biogeosciences, 20, 1195–1257, https://doi.org/10.5194/bg-20-1195-2023, https://doi.org/10.5194/bg-20-1195-2023, 2023
Short summary
Short summary
Ocean alkalinity is critical to the uptake of atmospheric carbon and acidification in surface waters. We review the representation of alkalinity and the associated calcium carbonate cycle in Earth system models. While many parameterizations remain present in the latest generation of models, there is a general improvement in the simulated alkalinity distribution. This improvement is related to an increase in the export of biotic calcium carbonate, which closer resembles observations.
Jérôme Pinti, Tim DeVries, Tommy Norin, Camila Serra-Pompei, Roland Proud, David A. Siegel, Thomas Kiørboe, Colleen M. Petrik, Ken H. Andersen, Andrew S. Brierley, and André W. Visser
Biogeosciences, 20, 997–1009, https://doi.org/10.5194/bg-20-997-2023, https://doi.org/10.5194/bg-20-997-2023, 2023
Short summary
Short summary
Large numbers of marine organisms such as zooplankton and fish perform daily vertical migration between the surface (at night) and the depths (in the daytime). This fascinating migration is important for the carbon cycle, as these organisms actively bring carbon to depths where it is stored away from the atmosphere for a long time. Here, we quantify the contributions of different animals to this carbon drawdown and storage and show that fish are important to the biological carbon pump.
Alastair J. M. Lough, Alessandro Tagliabue, Clément Demasy, Joseph A. Resing, Travis Mellett, Neil J. Wyatt, and Maeve C. Lohan
Biogeosciences, 20, 405–420, https://doi.org/10.5194/bg-20-405-2023, https://doi.org/10.5194/bg-20-405-2023, 2023
Short summary
Short summary
Iron is a key nutrient for ocean primary productivity. Hydrothermal vents are a source of iron to the oceans, but the size of this source is poorly understood. This study examines the variability in iron inputs between hydrothermal vents in different geological settings. The vents studied release different amounts of Fe, resulting in plumes with similar dissolved iron concentrations but different particulate concentrations. This will help to refine modelling of iron-limited ocean productivity.
Nicole M. Travis, Colette L. Kelly, Margaret R. Mulholland, and Karen L. Casciotti
Biogeosciences, 20, 325–347, https://doi.org/10.5194/bg-20-325-2023, https://doi.org/10.5194/bg-20-325-2023, 2023
Short summary
Short summary
The primary nitrite maximum is a ubiquitous upper ocean feature where nitrite accumulates, but we still do not understand its formation and the co-occurring microbial processes involved. Using correlative methods and rates measurements, we found strong spatial patterns between environmental conditions and depths of the nitrite maxima, but not the maximum concentrations. Nitrification was the dominant source of nitrite, with occasional high nitrite production from phytoplankton near the coast.
Natacha Le Grix, Jakob Zscheischler, Keith B. Rodgers, Ryohei Yamaguchi, and Thomas L. Frölicher
Biogeosciences, 19, 5807–5835, https://doi.org/10.5194/bg-19-5807-2022, https://doi.org/10.5194/bg-19-5807-2022, 2022
Short summary
Short summary
Compound events threaten marine ecosystems. Here, we investigate the potentially harmful combination of marine heatwaves with low phytoplankton productivity. Using satellite-based observations, we show that these compound events are frequent in the low latitudes. We then investigate the drivers of these compound events using Earth system models. The models share similar drivers in the low latitudes but disagree in the high latitudes due to divergent factors limiting phytoplankton production.
Abigale M. Wyatt, Laure Resplandy, and Adrian Marchetti
Biogeosciences, 19, 5689–5705, https://doi.org/10.5194/bg-19-5689-2022, https://doi.org/10.5194/bg-19-5689-2022, 2022
Short summary
Short summary
Marine heat waves (MHWs) are a frequent event in the northeast Pacific, with a large impact on the region's ecosystems. Large phytoplankton in the North Pacific Transition Zone are greatly affected by decreased nutrients, with less of an impact in the Alaskan Gyre. For small phytoplankton, MHWs increase the spring small phytoplankton population in both regions thanks to reduced light limitation. In both zones, this results in a significant decrease in the ratio of large to small phytoplankton.
Margot C. F. Debyser, Laetitia Pichevin, Robyn E. Tuerena, Paul A. Dodd, Antonia Doncila, and Raja S. Ganeshram
Biogeosciences, 19, 5499–5520, https://doi.org/10.5194/bg-19-5499-2022, https://doi.org/10.5194/bg-19-5499-2022, 2022
Short summary
Short summary
We focus on the exchange of key nutrients for algae production between the Arctic and Atlantic oceans through the Fram Strait. We show that the export of dissolved silicon here is controlled by the availability of nitrate which is influenced by denitrification on Arctic shelves. We suggest that any future changes in the river inputs of silica and changes in denitrification due to climate change will impact the amount of silicon exported, with impacts on Atlantic algal productivity and ecology.
Emily J. Zakem, Barbara Bayer, Wei Qin, Alyson E. Santoro, Yao Zhang, and Naomi M. Levine
Biogeosciences, 19, 5401–5418, https://doi.org/10.5194/bg-19-5401-2022, https://doi.org/10.5194/bg-19-5401-2022, 2022
Short summary
Short summary
We use a microbial ecosystem model to quantitatively explain the mechanisms controlling observed relative abundances and nitrification rates of ammonia- and nitrite-oxidizing microorganisms in the ocean. We also estimate how much global carbon fixation can be associated with chemoautotrophic nitrification. Our results improve our understanding of the controls on nitrification, laying the groundwork for more accurate predictions in global climate models.
Zuozhu Wen, Thomas J. Browning, Rongbo Dai, Wenwei Wu, Weiying Li, Xiaohua Hu, Wenfang Lin, Lifang Wang, Xin Liu, Zhimian Cao, Haizheng Hong, and Dalin Shi
Biogeosciences, 19, 5237–5250, https://doi.org/10.5194/bg-19-5237-2022, https://doi.org/10.5194/bg-19-5237-2022, 2022
Short summary
Short summary
Fe and P are key factors controlling the biogeography and activity of marine N2-fixing microorganisms. We found lower abundance and activity of N2 fixers in the northern South China Sea than around the western boundary of the North Pacific, and N2 fixation rates switched from Fe–P co-limitation to P limitation. We hypothesize the Fe supply rates and Fe utilization strategies of each N2 fixer are important in regulating spatial variability in community structure across the study area.
Claudia Eisenring, Sophy E. Oliver, Samar Khatiwala, and Gregory F. de Souza
Biogeosciences, 19, 5079–5106, https://doi.org/10.5194/bg-19-5079-2022, https://doi.org/10.5194/bg-19-5079-2022, 2022
Short summary
Short summary
Given the sparsity of observational constraints on micronutrients such as zinc (Zn), we assess the sensitivities of a framework for objective parameter optimisation in an oceanic Zn cycling model. Our ensemble of optimisations towards synthetic data with varying kinds of uncertainty shows that deficiencies related to model complexity and the choice of the misfit function generally have a greater impact on the retrieval of model Zn uptake behaviour than does the limitation of data coverage.
Yoshikazu Sasai, Sherwood Lan Smith, Eko Siswanto, Hideharu Sasaki, and Masami Nonaka
Biogeosciences, 19, 4865–4882, https://doi.org/10.5194/bg-19-4865-2022, https://doi.org/10.5194/bg-19-4865-2022, 2022
Short summary
Short summary
We have investigated the adaptive response of phytoplankton growth to changing light, nutrients, and temperature over the North Pacific using two physical-biological models. We compare modeled chlorophyll and primary production from an inflexible control model (InFlexPFT), which assumes fixed carbon (C):nitrogen (N):chlorophyll (Chl) ratios, to a recently developed flexible phytoplankton functional type model (FlexPFT), which incorporates photoacclimation and variable C:N:Chl ratios.
Jens Terhaar, Thomas L. Frölicher, and Fortunat Joos
Biogeosciences, 19, 4431–4457, https://doi.org/10.5194/bg-19-4431-2022, https://doi.org/10.5194/bg-19-4431-2022, 2022
Short summary
Short summary
Estimates of the ocean sink of anthropogenic carbon vary across various approaches. We show that the global ocean carbon sink can be estimated by three parameters, two of which approximate the ocean ventilation in the Southern Ocean and the North Atlantic, and one of which approximates the chemical capacity of the ocean to take up carbon. With observations of these parameters, we estimate that the global ocean carbon sink is 10 % larger than previously assumed, and we cut uncertainties in half.
Natasha René van Horsten, Hélène Planquette, Géraldine Sarthou, Thomas James Ryan-Keogh, Nolwenn Lemaitre, Thato Nicholas Mtshali, Alakendra Roychoudhury, and Eva Bucciarelli
Biogeosciences, 19, 3209–3224, https://doi.org/10.5194/bg-19-3209-2022, https://doi.org/10.5194/bg-19-3209-2022, 2022
Short summary
Short summary
The remineralisation proxy, barite, was measured along 30°E in the southern Indian Ocean during early austral winter. To our knowledge this is the first reported Southern Ocean winter study. Concentrations throughout the water column were comparable to observations during spring to autumn. By linking satellite primary production to this proxy a possible annual timescale is proposed. These findings also suggest possible carbon remineralisation from satellite data on a basin scale.
Zhibo Shao and Ya-Wei Luo
Biogeosciences, 19, 2939–2952, https://doi.org/10.5194/bg-19-2939-2022, https://doi.org/10.5194/bg-19-2939-2022, 2022
Short summary
Short summary
Non-cyanobacterial diazotrophs (NCDs) may be an important player in fixing N2 in the ocean. By conducting meta-analyses, we found that a representative marine NCD phylotype, Gamma A, tends to inhabit ocean environments with high productivity, low iron concentration and high light intensity. It also appears to be more abundant inside cyclonic eddies. Our study suggests a niche differentiation of NCDs from cyanobacterial diazotrophs as the latter prefers low-productivity and high-iron oceans.
Coraline Leseurre, Claire Lo Monaco, Gilles Reverdin, Nicolas Metzl, Jonathan Fin, Claude Mignon, and Léa Benito
Biogeosciences, 19, 2599–2625, https://doi.org/10.5194/bg-19-2599-2022, https://doi.org/10.5194/bg-19-2599-2022, 2022
Short summary
Short summary
Decadal trends of fugacity of CO2 (fCO2), total alkalinity (AT), total carbon (CT) and pH in surface waters are investigated in different domains of the southern Indian Ocean (45°S–57°S) from ongoing and station observations regularly conducted in summer over the period 1998–2019. The fCO2 increase and pH decrease are mainly driven by anthropogenic CO2 estimated just below the summer mixed layer, as well as by a warming south of the polar front or in the fertilized waters near Kerguelen Island.
Priscilla Le Mézo, Jérôme Guiet, Kim Scherrer, Daniele Bianchi, and Eric Galbraith
Biogeosciences, 19, 2537–2555, https://doi.org/10.5194/bg-19-2537-2022, https://doi.org/10.5194/bg-19-2537-2022, 2022
Short summary
Short summary
This study quantifies the role of commercially targeted fish biomass in the cycling of three important nutrients (N, P, and Fe), relative to nutrients otherwise available in water and to nutrients required by primary producers, and the impact of fishing. We use a model of commercially targeted fish biomass constrained by fish catch and stock assessment data to assess the contributions of fish at the global scale, at the time of the global peak catch and prior to industrial fishing.
Rebecca Chmiel, Nathan Lanning, Allison Laubach, Jong-Mi Lee, Jessica Fitzsimmons, Mariko Hatta, William Jenkins, Phoebe Lam, Matthew McIlvin, Alessandro Tagliabue, and Mak Saito
Biogeosciences, 19, 2365–2395, https://doi.org/10.5194/bg-19-2365-2022, https://doi.org/10.5194/bg-19-2365-2022, 2022
Short summary
Short summary
Dissolved cobalt is present in trace amounts in seawater and is a necessary nutrient for marine microbes. On a transect from the Alaskan coast to Tahiti, we measured seawater concentrations of dissolved cobalt. Here, we describe several interesting features of the Pacific cobalt cycle including cobalt sources along the Alaskan coast and Hawaiian vents, deep-ocean particle formation, cobalt activity in low-oxygen regions, and how our samples compare to a global biogeochemical model’s predictions.
Nicolas Metzl, Claire Lo Monaco, Coraline Leseurre, Céline Ridame, Jonathan Fin, Claude Mignon, Marion Gehlen, and Thi Tuyet Trang Chau
Biogeosciences, 19, 1451–1468, https://doi.org/10.5194/bg-19-1451-2022, https://doi.org/10.5194/bg-19-1451-2022, 2022
Short summary
Short summary
During an oceanographic cruise conducted in January 2020 in the south-western Indian Ocean, we observed very low CO2 concentrations associated with a strong phytoplankton bloom that occurred south-east of Madagascar. This biological event led to a strong regional CO2 ocean sink not previously observed.
Darren R. Clark, Andrew P. Rees, Charissa M. Ferrera, Lisa Al-Moosawi, Paul J. Somerfield, Carolyn Harris, Graham D. Quartly, Stephen Goult, Glen Tarran, and Gennadi Lessin
Biogeosciences, 19, 1355–1376, https://doi.org/10.5194/bg-19-1355-2022, https://doi.org/10.5194/bg-19-1355-2022, 2022
Short summary
Short summary
Measurements of microbial processes were made in the sunlit open ocean during a research cruise (AMT19) between the UK and Chile. These help us to understand how microbial communities maintain the function of remote ecosystems. We find that the nitrogen cycling microbes which produce nitrite respond to changes in the environment. Our insights will aid the development of models that aim to replicate and ultimately project how marine environments may respond to ongoing climate change.
Martí Galí, Marcus Falls, Hervé Claustre, Olivier Aumont, and Raffaele Bernardello
Biogeosciences, 19, 1245–1275, https://doi.org/10.5194/bg-19-1245-2022, https://doi.org/10.5194/bg-19-1245-2022, 2022
Short summary
Short summary
Part of the organic matter produced by plankton in the upper ocean is exported to the deep ocean. This process, known as the biological carbon pump, is key for the regulation of atmospheric carbon dioxide and global climate. However, the dynamics of organic particles below the upper ocean layer are not well understood. Here we compared the measurements acquired by autonomous robots in the top 1000 m of the ocean to a numerical model, which can help improve future climate projections.
Marie Barbieux, Julia Uitz, Alexandre Mignot, Collin Roesler, Hervé Claustre, Bernard Gentili, Vincent Taillandier, Fabrizio D'Ortenzio, Hubert Loisel, Antoine Poteau, Edouard Leymarie, Christophe Penkerc'h, Catherine Schmechtig, and Annick Bricaud
Biogeosciences, 19, 1165–1194, https://doi.org/10.5194/bg-19-1165-2022, https://doi.org/10.5194/bg-19-1165-2022, 2022
Short summary
Short summary
This study assesses marine biological production in two Mediterranean systems representative of vast desert-like (oligotrophic) areas encountered in the global ocean. We use a novel approach based on non-intrusive high-frequency in situ measurements by two profiling robots, the BioGeoChemical-Argo (BGC-Argo) floats. Our results indicate substantial yet variable production rates and contribution to the whole water column of the subsurface layer, typically considered steady and non-productive.
Filippa Fransner, Friederike Fröb, Jerry Tjiputra, Nadine Goris, Siv K. Lauvset, Ingunn Skjelvan, Emil Jeansson, Abdirahman Omar, Melissa Chierici, Elizabeth Jones, Agneta Fransson, Sólveig R. Ólafsdóttir, Truls Johannessen, and Are Olsen
Biogeosciences, 19, 979–1012, https://doi.org/10.5194/bg-19-979-2022, https://doi.org/10.5194/bg-19-979-2022, 2022
Short summary
Short summary
Ocean acidification, a direct consequence of the CO2 release by human activities, is a serious threat to marine ecosystems. In this study, we conduct a detailed investigation of the acidification of the Nordic Seas, from 1850 to 2100, by using a large set of samples taken during research cruises together with numerical model simulations. We estimate the effects of changes in different environmental factors on the rate of acidification and its potential effects on cold-water corals.
Guorong Zhong, Xuegang Li, Jinming Song, Baoxiao Qu, Fan Wang, Yanjun Wang, Bin Zhang, Xiaoxia Sun, Wuchang Zhang, Zhenyan Wang, Jun Ma, Huamao Yuan, and Liqin Duan
Biogeosciences, 19, 845–859, https://doi.org/10.5194/bg-19-845-2022, https://doi.org/10.5194/bg-19-845-2022, 2022
Short summary
Short summary
A predictor selection algorithm was constructed to decrease the predicting error in the surface ocean partial pressure of CO2 (pCO2) mapping by finding better combinations of pCO2 predictors in different regions. Compared with previous research using the same combination of predictors in all regions, using different predictors selected by the algorithm in different regions can effectively decrease pCO2 predicting errors.
Cited articles
Al-Mutairi, H. and Landry, M. R.: Active export of carbon and nitrogen at
station ALOHA by diel migrant zooplankton, Deep-Sea Res. Pt. II, 48,
2083–2103, https://doi.org/10.1016/S0967-0645(00)00174-0, 2001.
Altabet, M. A.: Variations in nitrogen isotopic composition between sinking
and suspended particles: implications for nitrogen cycling and particle
transformation in the open ocean, Deep-Sea Res. Pt. A, 35, 535–554,
https://doi.org/10.1016/0198-0149(88)90130-6, 1988.
Aminot, A. and Kérouel, R.: Dosage automatique des nutriments dans les
eaux marines?: méthodes en flux continu, Ifremer, Plouzané, 2007.
Atkinson, A., Shreeve, R. S., Pakhomov, E. A., Priddle, J., Blight, S. P.,
and Ward, P.: Zooplankton response to a phytoplankton bloom near South
Georgia, Antarctica, Mar. Ecol.-Prog. Ser., 144, 195–210,
https://doi.org/10.3354/meps144195, 1996.
Bacon, M. P., Cochran, J. K., Hirschberg, D., Hammar, T. R., and Fleer, A.
P.: Export flux of carbon at the equator during the EqPac time-series cruises
estimated from 234Th measurements, Deep.-Sea Res. Pt. II, 43,
1133–1153, https://doi.org/10.1016/0967-0645(96)00016-1, 1996.
Baines, S. R., Pace, M. L., and Karl, D. M.: Why does the relationship
between sinking flux and planktonic primary production differ between lakes
and oceans?, Limnol. Oceanogr., 39, 213–226, 1994.
Bar-Zeev, E., Avishay, I., Bidle, K. D., and Berman-Frank, I.: Programmed
cell death in the marine cyanobacterium Trichodesmium mediates carbon and
nitrogen export, ISME J., 7, 2340–2348, https://doi.org/10.1038/ismej.2013.121, 2013.
Benavides, M., Berthelot, H., Duhamel, S., Raimbault, P., and Bonnet, S.:
Dissolved organic matter uptake by Trichodesmium in the Southwest Pacific,
Sci. Rep., 7, 41315, https://doi.org/10.1038/srep41315, 2017.
Berthelot, H., Moutin, T., L'Helguen, S., Leblanc, K., Hélias, S.,
Grosso, O., Leblond, N., Charrière, B., and Bonnet, S.: Dinitrogen
fixation and dissolved organic nitrogen fueled primary production and
particulate export during the VAHINE mesocosm experiment (New Caledonia
lagoon), Biogeosciences, 12, 4099–4112,
https://doi.org/10.5194/bg-12-4099-2015, 2015.
Berthelot, H., Bonnet, S., Grosso, O., Cornet, V., and Barani, A.: Transfer
of diazotroph-derived nitrogen towards non-diazotrophic planktonic
communities: a comparative study between Trichodesmium erythraeum,
Crocosphaera watsonii and Cyanothece sp., Biogeosciences, 13, 4005–4021,
https://doi.org/10.5194/bg-13-4005-2016, 2016.
Berthelot, H., Benavides, M., Moisander, P. H., Grosso, O., and Bonnet, S.:
High-nitrogen fixation rates in the particulate and dissolved pools in the
Western Tropical Pacific (Solomon and Bismarck Seas), Geophys. Res. Lett., 2,
1–10, https://doi.org/10.1002/2017GL073856, 2017.
Bonnet, S., Biegala, I. C., Dutrieux, P., Slemons, L. O., and Capone, D. G.:
Nitrogen fixation in the western equatorial Pacific: Rates, diazotrophic
cyanobacterial size class distribution, and biogeochemical significance,
Global Biogeochem. Cy., 23, 1–13, https://doi.org/10.1029/2008GB003439, 2009.
Bonnet, S., Grosso, O., and Moutin, T.: Planktonic dinitrogen fixation along
a longitudinal gradient across the Mediterranean Sea during the stratified
period (BOUM cruise), Biogeosciences, 8, 2257–2267,
https://doi.org/10.5194/bg-8-2257-2011, 2011.
Bonnet, S., Rodier, M., Turk-Kubo, K. A., Germineaud, C., Menkes, C.,
Ganachaud, A., Cravatte, S., Raimbault, P., Campbell, E., Quéroué,
F., Sarthou, G., Desnues, A., Maes, C., and Eldin, G.: Contrasted
geographical distribution of N2 fixation rates and nifH phylotypes in
the Coral and Solomon Seas (southwestern Pacific) during austral winter
conditions, Global Biogeochem. Cy., 29, 1874–1892, https://doi.org/10.1002/2015GB005117,
2015.
Bonnet, S., Berthelot, H., Turk-Kubo, K. A., Cornet-Barthaux, V., Fawcett,
S., Berman-Frank, I., Barani, A., Grégori, G., Dekaezemacker, J.,
Benavides, M., and Capone, D. G.: Diazotroph derived nitrogen supports diatom
growth in the South West Pacific: A quantitative study using nanoSIMS,
Limnol. Oceanogr., 61, 1549–1562, https://doi.org/10.1002/lno.10300, 2016a.
Bonnet, S., Berthelot, H., Turk-Kubo, K., Fawcett, S., Rahav, E., L'Helguen,
S., and Berman-Frank, I.: Dynamics of N2 fixation and fate of
diazotroph-derived nitrogen in a low-nutrient, low-chlorophyll ecosystem:
results from the VAHINE mesocosm experiment (New Caledonia), Biogeosciences,
13, 2653–2673, https://doi.org/10.5194/bg-13-2653-2016, 2016b.
Bonnet, S., Caffin, M., Berthelot, H., and Moutin, T.: Hot spot of N2
fixation in the western tropical South Pacific pleads for a spatial
decoupling between N2 fixation and denitrification, P. Natl. Acad. Sci.
USA, 114, E2800–E2801, https://doi.org/10.1073/pnas.1619514114, 2017.
onnet, S., Caffin, M., Berthelot, H., Grosso, O., Benavides, M.,
Helias-Nunige, S., Guieu, C., Stenegren, M., and Foster, R. A.: In depth
characterization of diazotroph activity across the Western Tropical South
Pacific hot spot of N2 fixation, Biogeosciences Discuss.,
https://doi.org/10.5194/bg-2017-567, in review, 2018.
Böttjer, D., Dore, J. E., Karl, D. M., Letelier, R. M., Mahaffey, C.,
Wilson, S. T., Zehr, J. P., and Church, M. J.: Temporal variability of
nitrogen fixation and particulate nitrogen export at Station ALOHA, Limnol.
Oceanogr., 62, 200–216, https://doi.org/10.1002/lno.10386, 2017.
Bourbonnais, A., Lehmann, M. F., Waniek, J. J., and Schulz-Bull, D. E.:
Nitrate isotope anomalies reflect N2 fixation in the Azores Front region
(subtropical NE Atlantic), J. Geophys. Res.-Ocean., 114, 1–16,
https://doi.org/10.1029/2007JC004617, 2009.
Bouruet-Aubertot, P., Cuypers, Y., Le Goff, H., Rougier, G., de Verneuil, A.,
Doglioli, A., Picheral, M., Yohia, C., Caffin, M., Lefèvre, D., Petrenko,
A., and Moutin, T.: Longitudinal contrast in small scale turbulence along
20∘ S in the Pacific Ocean: origin and impact on biogeochemical
fluxes, Biogeosciences Discuss., in preparation, 2018.
Caffin, M., Foster, R., Berthelot, H., and Bonnet, S.: Fate of N2
fixation in the Western Tropical South Pacific Ocean: Transfer of
diazotroph-derived nitrogen to non-diazotrophic communities and export of
diazotrophs, Biogeosciences Discuss., in preparation, 2018.
Capone, D. G., Burns, J. A., Montoya, J. P., Subramaniam, A., Mahaffey, C.,
Gunderson, T., Michaels, A. F., and Carpenter, E. J.: Nitrogen fixation by
Trichodesmium spp.: An important source of new nitrogen to the tropical and
subtropical North Atlantic Ocean, Global Biogeochem. Cy., 19, 1–17,
https://doi.org/10.1029/2004GB002331, 2005.
Carlson, C. A. and Ducklow, H. W.: Dissolved organic carbon in the upper
ocean of the central equatorial Pacific Ocean, 1992: Daily and finescale
vertical variations, Deep-Sea Res. Pt. II, 42, 639–656,
https://doi.org/10.1016/0967-0645(95)00023-J, 1995.
Carlson, C. A., Ducklow, H. W., and Michaels, A. F.: Annual flux of dissolved
organic carbon from the euphotic zone in the northwestern Sargasso Sea,
Nature, 371, 405–408, https://doi.org/10.1038/371405a0, 1994.
Chen, Y. L. L., Chen, H. Y., and Lin, Y. H.: Distribution and downward flux
of Trichodesmium in the South China Sea as influenced by the transport from
the Kuroshio Current, Mar. Ecol.-Prog. Ser., 259, 47–57,
https://doi.org/10.3354/meps259047, 2003.
Church, M. J., Short, C. M., Jenkins, B. D., Karl, D. M., and Zehr, J. P.:
Temporpl Patterns of nitrogenase gene (nifH) expression in the oligotrophic
North Pacific Ocean, Appl. Environ. Microb., 71, 5362–5370,
https://doi.org/10.1128/AEM.71.9.5362-5370.2005, 2005.
Copin-Montégut, G. and Avril, B.: Vertical distribution and temporal
variation of dissolved organic carbon in the North-Western Mediterranean Sea,
Deep-Sea Res. Pt. I, 40, 1963–1972, https://doi.org/10.1016/0967-0637(93)90041-Z, 1993.
Dabundo, R., Lehmann, M. F., Treibergs, L., Tobias, C. R., Altabet, M. A.,
Moisander, P. H., and Granger, J.: The contamination of commercial
15N2 gas stocks with 15N labeled nitrate and ammonium
and consequences for nitrogen fixation measurements, PLoS ONE, 9, e110335,
https://doi.org/10.1371/journal.pone.0110335, 2014.
Dam, H. G., Miller, C. A., and Jonasdottir, S. H.: The Trophic Role of
Mesozooplankton at 47-Degrees-N, 20-Degrees-W during the North-Atlantic Bloom
Experiment, Deep-Sea Res. Pt. II, 40, 197–212,
https://doi.org/10.1016/0967-0645(93)90013-D, 1993.
Dam, H. G., Roman, M. R., and Youngbluth, M. J.: Downward export of
respiratory carbon and dissolved inorganic nitrogen by diel-migrant
mesozooplankton at the JGOFS Bermuda time-series station, Deep-Sea Res. Pt.
I, 42, 1187–1197, https://doi.org/10.1016/0967-0637(95)00048-B, 1995.
Dekaezemacker, J. and Bonnet, S.: Sensitivity of N2 fixation to combined
nitrogen forms (NO
Dentener, F., Drevet, J., Lamarque, J. F., Bey, I., Eickhout, B., Fiore, A.
M., Hauglustaine, D., Horowitz, L. W., Krol, M., Kulshrestha, U. C.,
Lawrence, M., Galy-Lacaux, C., Rast, S., Shindell, D., Stevenson, D., Van
Noije, T., Atherton, C., Bell, N., Bergman, D., Butler, T., Cofala, J.,
Collins, B., Doherty, R., Ellingsen, K., Galloway, J., Gauss, M., Montanaro,
V., Muller, J. F., Pitari, G., Rodriguez, J., Sanderson, M., Solmon, F.,
Strahan, S., Schultz, M., Sudo, K., Szopa, S., and Wild, O.: Nitrogen and
sulfur deposition on regional and global scales: a multimodel evaluation,
Global Biogeochem. Cy., 20, GB4003, https://doi.org/10.1029/2005GB002672, 2006.
Deutsch, C. A., Sarmiento, J. L., Sigman, D. M., Gruber, N., and Dunne, J.
P.: Spatial coupling of nitrogen inputs and losses in the ocean, Nature, 445,
163–167, https://doi.org/10.1038/nature05392, 2007.
de Verneil, A., Rousselet, L., Doglioli, A. M., Petrenko, A. A., and Moutin,
T.: The fate of a southwest Pacific bloom: gauging the impact of submesoscale
vs. mesoscale circulation on biological gradients in the subtropics,
Biogeosciences, 14, 3471–3486, https://doi.org/10.5194/bg-14-3471-2017,
2017.
de Verneil, A., Rousselet, L., Doglioli, A. M., Petrenko, A. A., Maes, C.,
Bouruet-Aubertot, P., and Moutin, T.: OUTPACE long duration stations:
physical variability, context of biogeochemical sampling, and evaluation of
sampling strategy, Biogeosciences, 15, 2125–2147,
https://doi.org/10.5194/bg-15-2125-2018, 2018.
Doglioli, A. M., Nencioli, F., Petrenko, A. A., Rougier, G., Fuda, J.-L., and
Grima, N.: A software package and hardware tools for in situ experiments in a
Lagrangian reference frame, J. Atmos. Ocean. Tech., 30, 1940–1950, 2013.
Dore, J. E., Brum, J. R., Tupas, L. M., and Karl, D. M.: Seasonal and
interannual variability in sources of nitrogen supporting export in the
oligotrophic subtropical North Pacific Ocean, Limnol. Oceanogr., 47,
1595–1607, 2002.
Dore, J. E., Letelier, R. M., Church, M. J., Lukas, R., and Karl, D. M.:
Summer phytoplankton blooms in the oligotrophic North Pacific Subtropical
Gyre: Historical perspective and recent observations, Prog. Oceanogr., 76,
2–38, https://doi.org/10.1016/j.pocean.2007.10.002, 2008.
d'Ovidio, F., Della Penna, A., Trull, T. W., Nencioli, F., Pujol, M.-I., Rio,
M.-H., Park, Y.-H., Cotté, C., Zhou, M., and Blain, S.: The
biogeochemical structuring role of horizontal stirring: Lagrangian
perspectives on iron delivery downstream of the Kerguelen Plateau,
Biogeosciences, 12, 5567–5581, https://doi.org/10.5194/bg-12-5567-2015,
2015.
Dron, A., Rabouille, S., Claquin, P., Talec, A., Raimbault, V., and Sciandra,
A.: Photoperiod length paces the temporal orchestration of cell cycle and
carbon-nitrogen metabolism in Crocosphaera watsonii, Environ. Microbiol., 15,
3292–3304, https://doi.org/10.1111/1462-2920.12163, 2013.
Eppley, R. W. and Peterson, B. J.: Particulate organic matter flux and
planktonic new production in the deep ocean, Nature, 282, 677–680,
https://doi.org/10.1038/282677a0, 1979.
Fernández-Castro, B., Mouriño-Carballido, B., Marañón, E.,
Chouciño, P., Gago, J., Ramírez, T., Vidal, M., Bode, A., Blasco,
D., Royer, S.-J., Estrada, M., and Simó, R.: Importance of salt fingering
for new nitrogen supply in the oligotrophic ocean, Nat. Commun., 6, 8002,
https://doi.org/10.1038/ncomms9002, 2015.
Fonseca-Batista, D., Dehairs, F., Riou, V., Fripiat, F., Elskens, M., Deman,
F., Brion, N., Quéroue, F., Bode, M., and Auel, H.: Nitrogen fixation in
the eastern Atlantic reaches similar levels in the Southern and Northern
Hemisphere, J. Geophys. Res.-Ocean., 122, 587–601, 2017.
Foster, R. A. and Zehr, J. P.: Characterization of diatom-South Pacific gyrecyanobacteria
symbioses on the basis of nifH, hetR and 16S rRNA sequences, Environ.
Microbiol., 8, 1913–1925, https://doi.org/10.1111/j.1462-2920.2006.01068.x, 2006.
Foster, R. A., Subramaniam, A., Mahaffey, C., Carpenter, E. J., Capone, D.
G., and Zehr, J. P.: Influence of the Amazon River plume on distributions of
free-living and symbiotic cyanobacteria in the western tropical north
Atlantic Ocean, Limnol. Oceanogr., 52, 517–532,
https://doi.org/10.4319/lo.2007.52.2.0517, 2007.
Garcia, N., Raimbault, P., Gouze, E., and Sandroni, V.: Fixation de diazote
et production primaire en Méditerranée occidentale, C. R. Biol., 329,
742–750, https://doi.org/10.1016/j.crvi.2006.06.006, 2006.
Gradoville , M. R., Bombar, D., Crump, B. C., Letelier, R. M., Zehr, J. P.,
and White, A. E.: Diversity and activity of nitrogen-fixing communities
across ocean basins, Limnol. Oceanogr., 62, 1895–1909, 2017.
Großkopf, T., Mohr, W., Baustian, T., Schunck, H., Gill, D., Kuypers, M.
M. M., Lavik, G., Schmitz, R. A., Wallace, D. W. R., and LaRoche, J.:
Doubling of marine dinitrogen-fixation rates based on direct measurements,
Nature, 488, 361–364, https://doi.org/10.1038/nature11338, 2012.
Gruber, N.: The Marine Nitrogen Cycle: Overview and Challenges, Nitrogen Mar.
Environ., 1–50, https://doi.org/10.1016/B978-0-12-372522-6.00001-3, 2008.
Gruber, N. and Sarmiento, J. L.: Global patterns of marine nitrogen fixation
and denitrification, Global Biogeochem. Cy., 11, 235–266,
https://doi.org/10.1029/97GB00077, 1997.
Guieu, C., Bonnet, S., Petrenko, A., Menkes, C., Chavagnac, V., Desboeufs,
C., Maes, C., and Moutin, T.: Iron from a submarine source impacts the
productive layer of the Western Tropical South Pacific (WTSP), Scientific
Reports, in review, 2018.
Hannides, C. C. S., Landry, M. R., Benitez-Nelson, C. R., Styles, R. M.,
Montoya, J. P., and Karl, D. M.: Export stoichiometry and migrant-mediated
flux of phosphorus in the North Pacific Subtropical Gyre, Deep-Sea Res. Pt.
I, 56, 73–88, https://doi.org/10.1016/j.dsr.2008.08.003, 2009.
Hewson, I., Govil, S. R., Capone, D. G., Carpenter, E. J., and Fuhrman, J.
A.: Evidence of Trichodesmium viral lysis and potential significance for
biogeochemical cycling in the oligotrophic ocean, Aquat. Microb. Ecol., 36,
1–8, https://doi.org/10.3354/ame036001, 2004.
Hynes, A. M., Webb, E. A., Doney, S. C., and Waterbury, J. B.: Comparison of
cultured trichodesmium (cyanophyceae) with species characterized from the
field, J. Phycol., 48, 196–210, https://doi.org/10.1111/j.1529-8817.2011.01096.x, 2012.
INSU/CNRS LEFE CYBER: available at:
http://www.obs-vlfr.fr/proof/php/outpace/outpace.php (last access: 27 April 2018), 2017.
JGOFS: Core measurements protocols?: report of the core measurement working
group, Jt. Glob. Ocean Flux Study, JGOFS repo, SCOR 1-40, 1988.
Kana, T. M., Darkangelo, C., Hunt, M. D., Oldham, J. B., Bennett, G. E., and
Cornwell, J. C.: Membrane Inlet Mass Spectrometer for Rapid High-Precision
Determination of N2, O2, and Ar in Environmental Water Samples,
Anal. Chem., 66, 4166–4170, https://doi.org/10.1021/ac00095a009, 1994.
Kanakidou, M., Duce, R. A., Prospero, J. M., Baker, A. R., BenitezNelson, C.,
Dentener, F. J., Hunter, K. A., Liss, P. S., Mahowald, N., Okin, G. S.,
Sarin, M., Tsigaridis, K., Uematsu, M., Zamora, L. M., and Zhu, T.:
Atmospheric fluxes of organic N and P to the global ocean, Global Biogeochem.
Cy., 26, GB3026, https://doi.org/10.1029/2011GB004277, 2012.
Karl, D. M., Christian, J. R., Dore, J. E., Hebel, D. V., Letelier, R. M.,
Tupas, L. M., and Winn, C. D.: Seasonal and interannual variability in
primary production and particle flux at Station ALOHA, Deep-Sea Res. Pt. II,
43, 539–568, https://doi.org/10.1016/0967-0645(96)00002-1, 1996.
Karl, D. M., Letelier, R. M., Tupas, L. M., Dore, J. E., Christian, J. R.,
and Hebel, D. V.: The role of nitrogen fixation in biogeochemical cycling in
the subtropical North Pacific Ocean, Nature, 388, 533–538,
https://doi.org/10.1038/41474, 1997.
Karl, D. M., Michaels, A. F., Bergman, B., Capone, D. G., Carpenter, E. J.,
Letelier, R., Lipschultz, F., Paerl, H., Sigman, D., and Stal, L.: Dinitrogen
fixation in the world's oceans, Biogeochemistry, 57–58, 47–98,
https://doi.org/10.1023/A:1015798105851, 2002.
Karl, D. M., Bates, N., Emerson, S., Harrisson, P. J., Jeandel, C., Liu, K.
K., Marty, J. C., Michaels, A. F., Miquel, J. C., Neuer, S., Nojiri, Y., and
Wong, C. S.: Temporal studies of biogeochemical processes determined from
ocean time-series observations during the JGOFS era, in: Ocean
Biogeochemistry: The role of the ocean carbon cycle in global change, edited
by: Fasham, M. J. R., International Geosphere-Biosphere Programme Book
Series, Springer-Verlag, New York, 239–267, 2003.
Karl, D. M., Church, M. J., Dore, J. E., Letelier, R. M., and Mahaffey, C.:
Predictable and efficient carbon sequestration in the North Pacific Ocean
supported by symbiotic nitrogen fixation, P. Natl. Acad. Sci. USA, 109,
1842–1849, https://doi.org/10.1073/pnas.1120312109, 2012.
Klawonn, I., Lavik, G., Böning, P., Marchant, H. K., Dekaezemacker, J.,
Mohr, W., and Ploug, H.: Simple approach for the preparation of
15−15N2-enriched water for nitrogen fixation assessments:
Evaluation, application and recommendations, Front. Microbiol., 6, 769,
https://doi.org/10.3389/fmicb.2015.00769, 2015.
Knapp, A. N.: The sensitivity of marine N2 fixation to dissolved
inorganic nitrogen, Front. Microbiol., 3, 1–14,
https://doi.org/10.3389/fmicb.2012.00374, 2012.
Knapp, A. N., Sigman, D. M., and Lipschultz, F.: N isotopic composition of
dissolved organic nitrogen and nitrate at the Bermuda Atlantic Time-series
study site, Global Biogeochem. Cy., 19, 1–15, https://doi.org/10.1029/2004GB002320,
2005.
Knapp, A. N., Difiore, P. J., Deutsch, C., Sigman, D. M., and Lipschultz, F.:
Nitrate isotopic composition between Bermuda and Puerto Rico: implications for
N2 fixation in the Atlantic Ocean, Global Biogeochem. Cy., 22,
GB3014, https://doi.org/10.1029/2007GB003107, 2008.
Knapp, A. N., McCabe, K. M., Grosso, O., Leblond, N., Moutin, T., and Bonnet,
S.: Distribution and rates of nitrogen fixation in the western tropical South
Pacific Ocean constrained by nitrogen isotope budgets, Biogeosciences
Discuss., https://doi.org/10.5194/bg-2017-564, in review, 2018.
Knauer, G. A., Redalje, D. G., Harrison, W. G. and Karl, D. M.: New
production at the VERTEX time-series site, Deep-Sea Res. Pt. A, 37,
1121–1134, https://doi.org/10.1016/0198-0149(90)90054-Y, 1990.
Lam, P. J. and Bishop, J. K. B.: High biomass, low export regimes in the
Southern Ocean, Deep-Sea Res. Pt. II, 54, 601–638,
https://doi.org/10.1016/j.dsr2.2007.01.013, 2007.
Le Borgne, R. and Rodier, M.: Net zooplankton and the biological pump: A
comparison between the oligotrophic and mesotrophic equatorial Pacific,
Deep-Sea Res. Pt. II, 44, 2003–2023, https://doi.org/10.1016/S0967-0645(97)00034-9,
1997.
Longhurst, A. R. and Glen Harrison, W.: Vertical nitrogen flux from the
oceanic photic zone by diel migrant zooplankton and nekton, Deep-Sea Res. Pt.
A, 35, 881–889, https://doi.org/10.1016/0198-0149(88)90065-9, 1988.
Longhurst, A. R. and Williams, R. G.: Carbon flux by seasonal vertical
migrant cpoepods is a small number, J. Plankton Res., 14, 1495–1509, 1992.
Longhurst, A. R., Bedo, A. W., Harrison, W. G., Head, E. J. H., Horne, E. P.,
Irwin, B., and Morales, C. E.: NFLUX: a test of vertical nitrogen flux by
diel migrant biota, Deep-Sea Res. Pt. A, 36, 1705–1719,
https://doi.org/10.1016/0198-0149(89)90067-8, 1989.
Longhurst, A. R., Bedo, A. W., Harrison, W. G., Head, E. J. H., and Sameoto,
D. D.: Vertical flux of respiratory carbon by oceanic diel migrant biota,
Deep-Sea Res. Pt. A, 37, 685–694, https://doi.org/10.1016/0198-0149(90)90098-G, 1990.
Luo, Y.-W., Doney, S. C., Anderson, L. A., Benavides, M., Berman-Frank, I.,
Bode, A., Bonnet, S., Boström, K. H., Böttjer, D., Capone, D. G.,
Carpenter, E. J., Chen, Y. L., Church, M. J., Dore, J. E., Falcón, L. I.,
Fernández, A., Foster, R. A., Furuya, K., Gómez, F., Gundersen, K.,
Hynes, A. M., Karl, D. M., Kitajima, S., Langlois, R. J., LaRoche, J.,
Letelier, R. M., Marañón, E., McGillicuddy Jr., D. J., Moisander, P.
H., Moore, C. M., Mouriño-Carballido, B., Mulholland, M. R., Needoba, J.
A., Orcutt, K. M., Poulton, A. J., Rahav, E., Raimbault, P., Rees, A. P.,
Riemann, L., Shiozaki, T., Subramaniam, A., Tyrrell, T., Turk-Kubo, K. A.,
Varela, M., Villareal, T. A., Webb, E. A., White, A. E., Wu, J., and Zehr, J.
P.: Database of diazotrophs in global ocean: abundance, biomass and nitrogen
fixation rates, Earth Syst. Sci. Data, 4, 47–73,
https://doi.org/10.5194/essd-4-47-2012, 2012.
Mahaffey, C., Williams, R. G., Wolff, G. A., Mahowald, N. M., Anderson, W.,
and Woodward, M.: Biogeochemical signatures of nitrogen fixation in the
eastern North Atlantic, Geophys. Res. Lett., 30, 33–36,
https://doi.org/10.1029/2002GL016542, 2003.
Mahaffey, C., Michaels, A. F., and Capone, D. G.: The conundrum of marine
N2 fixation, Am. J. Sci., 305, 546–595, https://doi.org/10.2475/ajs.305.6-8.546,
2005.
Martínez-Pérez, C., Mohr, W., Löscher, C. R., Dekaezemacker, J.,
Littmann, S., Yilmaz, P., Lehnen, N., Fuchs, B. M., Lavik, G., Schmitz, R.
A., LaRoche, J., and Kuypers, M. M. M.: The small unicellular diazotrophic
symbiont, UCYN-A, is a key player in the marine nitrogen cycle, Nat.
Microbiol., 1, 16163, https://doi.org/10.1038/nmicrobiol.2016.163, 2016.
Mohr, W., Großkopf, T., Wallace, D. W. R., and LaRoche, J.:
Methodological underestimation of oceanic nitrogen fixation rates, PLoS One,
5, 1–7, https://doi.org/10.1371/journal.pone.0012583, 2010.
Moisander, P. H., Beinart, R. A., Voss, M., and Zehr, J. P.: Diversity and
abundance of diazotrophic microorganisms in the South China Sea during
intermonsoon, ISME J., 2, 954–967, https://doi.org/10.1038/ismej.2008.51, 2008.
Moisander, P. H., Beinart, R. A., Hewson, I., White, A. E., Johnson, K. S.,
Carlson, C. A., Montoya, J. P., and Zehr, J. P.: Unicellular Cyanobacterial
Distributions Broaden the Oceanic N2 Fixation Domain, Science, 327,
1512–1514, https://doi.org/10.1126/science.1185468, 2010.
Montoya, J. P., Voss, M., Kahler, P., and Capone, D. G.: A Simple ,
High-Precision , High-Sensitivity Tracer Assay for N2 Fixation, Appl.
Environ. Microbiol., 62, 986–993, 1996.
Montoya, J. P., Holl, C. M., Zehr, J. P., Hansen, A., Villareal, T. A., and
Capone, D. G.: High rates of N2 fixation by unicellular diazotrophs in
the oligotrophic Pacific Ocean, Nature, 430, 1027–1031,
https://doi.org/10.1038/nature02824, 2004.
Monroy, P., Hernández-García, E., Rossi, V., and López, C.:
Modeling the dynamical sinking of biogenic particles in oceanic flow, Nonlin.
Processes Geophys., 24, 293–305, https://doi.org/10.5194/npg-24-293-2017,
2017.
Moore, C. M., Mills, M. M., Arrigo, K. R., Berman-Frank, I., Bopp, L., Boyd,
P. W., Galbraith, E. D., Geider, R. J., Guieu, C., Jaccard, S. L., Jickells,
T. D., La Roche, J., Lenton, T. M., Mahowald, N. M., Marañón, E.,
Marinov, I., Moore, J. K., Nakatsuka, T., Oschlies, A., Saito, M. A.,
Thingstad, T. F., Tsuda, A., and Ulloa, O.: Processes and patterns of oceanic
nutrient limitation, Nat. Geosci., 6, 701–710, https://doi.org/10.1038/ngeo1765, 2013.
Mourino-Carballido, B., Graña, R., Fernández, A., Bode, A., Varela,
M., Domínguez, J., Escànez, J., de Armas, D., and Marañón,
E.: Importance of N2 fixation vs. nitrate eddy diffusion along a
latitudinal transect in the Atlantic Ocean, Limnol. Oceanogr., 56, 999–1007,
https://doi.org/10.4319/lo.2011.56.3.0999, 2011.
Moutin, T. and Bonnet, S.: OUTPACE, https://doi.org/10.17600/15000900,
2015.
Moutin, T. and Prieur, L.: Influence of anticyclonic eddies on the
Biogeochemistry from the Oligotrophic to the Ultraoligotrophic Mediterranean
(BOUM cruise), Biogeosciences, 9, 3827–3855,
https://doi.org/10.5194/bg-9-3827-2012, 2012.
Moutin, T. and Raimbault, P.: Primary production, carbon export and nutrients
availability in western and eastern Mediterranean Sea in early summer 1996
(MINOS cruise), J. Marine Syst., 33–34, 273–288,
https://doi.org/10.1016/S0924-7963(02)00062-3, 2002.
Moutin, T., Van Den Broeck, N., Beker, B., Dupouy, C., Rimmelin, P., and Le
Bouteiller, A.: Phosphate availability controls Trichodesmium spp. biomass in
the SW Pacific Ocean, Mar. Ecol.-Prog. Ser., 297, 15–21,
https://doi.org/10.3354/meps297015, 2005.
Moutin, T., Karl, D. M., Duhamel, S., Rimmelin, P., Raimbault, P., Van Mooy,
B. A. S., and Claustre, H.: Phosphate availability and the ultimate control
of new nitrogen input by nitrogen fixation in the tropical Pacific Ocean,
Biogeosciences, 5, 95–109, https://doi.org/10.5194/bg-5-95-2008, 2008.
Moutin, T., Doglioli, A. M., de Verneil, A., and Bonnet, S.: Preface: The
Oligotrophy to the UlTra-oligotrophy PACific Experiment (OUTPACE cruise, 18
February to 3 April 2015), Biogeosciences, 14, 3207–3220,
https://doi.org/10.5194/bg-14-3207-2017, 2017.
Moutin, T., Wagener, T., Caffin, M., Fumenia, A., Gimenez, A., Baklouti, M.,
Bouruet-Aubertot, P., Pujo-Pay, M., Leblanc, K., Lefevre, D., Helias Nunige,
S., Leblond, N., Grosso, O., and de Verneil, A.: Nutrient availability and
the ultimate control of the biological carbon pump in the Western Tropical
South Pacific Ocean, Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-565, in
review, 2018.
Nelson, D. M., Tréguer, P., Brzezinski, M. A., Leynaert, A., and
Quéguiner, B.: Production and dissolution of biogenic silica in the
ocean: Revised global estimates, comparison with regional data and
relationship to biogenic sedimentation, Global Biogeochem. Cy., 9, 359–372,
https://doi.org/10.1029/95GB01070, 1995.
Nodder, S. D. and Waite, A. M.: Is Southern Ocean organic carbon and biogenic
silica export enhanced by iron-stimulated increases in biological production?
Sediment trap results from SOIREE, Deep-Sea Res. Pt. II, 48, 2681–2701,
https://doi.org/10.1016/S0967-0645(01)00014-5, 2001.
Olli, K., Wexels Riser, C., Wassmann, P., Ratkova, T., Arashkevich, E., and
Pasternak, A.: Seasonal variation in vertical flux of biogenic matter in the
marginal ice zone and the central Barents Sea, J. Marine Syst., 38, 189–204,
https://doi.org/10.1016/S0924-7963(02)00177-X, 2002.
Painter, S. C., Patey, M. D., Forryan, A., and Torres-Valdés, S.:
Evaluating the balance between vertical diffusive nitrate supply and nitrogen
fixation with reference to nitrate uptake in the eastern subtropical North
Atlantic Ocean, J. Geophys. Res.-Ocean., 118, 5732–5749,
https://doi.org/10.1002/jgrc.20416, 2013.
Petrenko, A. A., Doglioli, A. M, Nencioli, F., Kersalé, M., Hu, Z., and
d'Ovidio, F.: A review of the LATEX project: mesoscale to submesoscale
processes in a coastal environment, Ocean Dynam., 67, 513–533, 2017.
Raimbault, P. and Garcia, N.: Evidence for efficient regenerated production
and dinitrogen fixation in nitrogen-deficient waters of the South Pacific
Ocean: impact on new and export production estimates, Biogeosciences, 5,
323–338, https://doi.org/10.5194/bg-5-323-2008, 2008
Reigstad, M., Wexels Riser, C., Wassmann, P., and Ratkova, T.: Vertical
export of particulate organic carbon: Attenuation, composition and loss rates
in the northern Barents Sea, Deep-Sea Res. Pt. II, 55, 2308–2319,
https://doi.org/10.1016/j.dsr2.2008.05.007, 2008.
Rembauville, M., Blain, S., Armand, L., Quéguiner, B., and Salter, I.:
Export fluxes in a naturally iron-fertilized area of the Southern Ocean –
Part 2: Importance of diatom resting spores and faecal pellets for export,
Biogeosciences, 12, 3171–3195, https://doi.org/10.5194/bg-12-3171-2015,
2015.
Rijkenberg, M. J. A., Langlois, R. J., Mills, M. M., Patey, M. D., Hill, P.
G., Nielsdóttir, M. C., Compton, T. J., LaRoche, J., and Achterberg E.
P.: Environmental forcing of nitrogen fixation in the Eastern Tropical and
Sub-Tropical North Atlantic Ocean, PLoS ONE, 6, e28989,
https://doi.org/10.1371/journal.pone.0028989, 2011.
Scharek, R., Tupas, L. M., and Karl, D. M.: Diatom fluxes to the deep sea in
the oligotrophic North Pacific gyre at Station ALOHA, Mar. Ecol.-Prog. Ser.,
182, 55–67, https://doi.org/10.3354/meps182055, 1999a.
Scharek, R., Latasa, M., Karl, D. M., and Bidigare, R. R.: Temporal
variations in diatom abundance and downward vertical flux in the oligotrophic
North Pacific gyre, Deep-Sea Res. Pt. I, 46, 1051–1075,
https://doi.org/10.1016/S0967-0637(98)00102-2, 1999b.
Shiozaki, T., Kodama, T., and Furuya, K.: Large-scale impact of the island
mass effect through nitrogen fixation in the western South Pacific Ocean,
Geophys. Res. Lett., 41, 2907–2913, https://doi.org/10.1002/2014GL059835, 2014.
Shiozaki, T., Nagata, T., Ijichi, M., and Furuya, K.: Nitrogen fixation and
the diazotroph community in the temperate coastal region of the northwestern
North Pacific, Biogeosciences, 12, 4751–4764,
https://doi.org/10.5194/bg-12-4751-2015, 2015.
Short, S. M., Jenkins, B. D., and Zehr, J. P.: The spatial and temporal
distribution of two diazotrophic bacteria in the Chesapeake Bay, Appl.
Environ. Microb., 70, 2186–2192, https://doi.org/10.1128/AEM.70.4.2186-2192.2004, 2004.
Spungin, D., Belkin, N., Foster, R., Stenegren, M., Caputo, A., Pujo-Pay, M.,
Leblond, N., Dupouy, C., Bonnet, S., and Berman-Frank, I.: Programmed cell
death in diazotrophs and the fate of organic matter in the Western Tropical
South Pacific Ocean during the OUTPACE cruise, Biogeosciences Discuss.,
https://doi.org/10.5194/bg-2018-3, in review, 2018.
Stenegren, M., Caputo, A., Berg, C., Bonnet, S., and Foster, R. A.:
Distribution and drivers of symbiotic and free-living diazotrophic
cyanobacteria in the western tropical South Pacific, Biogeosciences, 15,
1559–1578, https://doi.org/10.5194/bg-15-1559-2018, 2018.
Stukel, M. R., Ohman, M. D., Benitez-Nelson, C. R., and Landry, M. R.:
Contributions of mesozooplankton to vertical carbon export in a coastal
upwelling system, Mar. Ecol.-Prog. Ser., 491, 47–65, https://doi.org/10.3354/meps10453,
2013.
Stukel, M. R., Benitez-Nelson, C. R., Decima, M., Taylor, A. G., Buchwald,
C., and Landry, M. R.: The biological pump in the Costa Rica Dome: An
open-ocean upwelling system with high new production and low export, J.
Plankton Res., 38, 348–365, https://doi.org/10.1093/plankt/fbv097, 2015.
Subramaniam, A., Yager, P. L., Carpenter, E. J., Mahaffey, C., Björkman,
K. M., Cooley, S., Kustka, A. B., Montoya, J. P., Sanudo-Wilhelmy, S. A.,
Shipe, R., and Capone, D. G.: Amazon River enhances diazotrophy and carbon
sequestration in the tropical North Atlantic Ocean, P. Natl. Acad. Sci. USA,
105, 10460–10465, https://doi.org/10.1073/pnas.0710279105, 2008.
Sun, J. and Liu, D.: Geometric models for calculating cell biovolume and
surface area for phytoplankton, J. Plankton Res., 25, 1331–1346,
https://doi.org/10.1093/plankt/fbg096, 2003.
Thomalla, S., Turnewitsch, R., Lucas, M., and Poulton, A.: Particulate
organic carbon export from the North and South Atlantic gyres: The
234Th/238U disequilibrium approach, Deep-Sea Res. Pt. II, 53,
1629–1648, https://doi.org/10.1016/j.dsr2.2006.05.018, 2006.
Toggweiler, J. R.: Is the downward dissolved organic matter (DOM) flux
important in carbon transport?, Productivity in the Ocean: Present and Past,
edited by: Berger, W. H., Smetacek, V. S., and Wefer, G., Wiley, New York,
65–83, 1989.
Van Wambeke, F., Gimenez, A., Duhamel, S., Dupouy, C., Lefevre, D., Pujo-Pay,
M., and Moutin, T.: Dynamics of phytoplankton and heterotrophic
bacterioplankton in the western tropical South Pacific Ocean along a gradient
of diversity and activity of diazotrophs, Biogeosciences Discuss.,
https://doi.org/10.5194/bg-2017-556, in review, 2018.
Verity, P. G., Robertson, C. Y., Tronzo, C. R., Andrews, M. G., Nelson, J.
R., and Sieracki, M. E.: Relationships between cell volume and the carbon and
nitrogen content of marine photosynthetic nanoplankton, Limnol. Oceanogr.,
37, 1434–1446, https://doi.org/10.4319/lo.1992.37.7.1434, 1992.
Villareal, T. A.: Division cycles in the nitrogen-fixing rhizosolenia
(Baciliariophyceae)-richelia (nostocaceae) symbiosis, Br. Phycol. J., 24,
357–365, https://doi.org/10.1080/00071618900650371, 1989.
Vinogradov, M. E.: Vertical distribution of the oceanic zooplankton, Moscow:
Nauka, 318 pp., 1968 (in Russian), Engl. transl. by Israel Progr. Scient.
Transl., Jerusalem, 339 pp., 1970.
Vong, R. J., Vong, I. J., Vickers, D., and Covert, D. S.: Size-dependent
aerosol deposition velocities during BEARPEX'07, Atmos. Chem. Phys., 10,
5749–5758, https://doi.org/10.5194/acp-10-5749-2010, 2010.
Walsby, A. E.: The gas vesicles and buoyancy of Trichodesmium, in: Marine
pelagic cyanobacteria: Trichodesmium and other diazotrophs, Springer, the
Netherlands, 141–161, 1992.
Wassman, F.: Relationships between primary and export production in the
boreal coastal zone of the North Atlantic, Limnol. Oceanogr., 35, 464–471,
1990.
Weiss, R. F.: The solubility of nitrogen, oxygen and argon in water and
seawater, Deep-Sea Res., 17, 721–735, 1970.
Wexels Riser, C., Wassmann, P., Reigstad, M. and Seuthe, L.: Vertical flux
regulation by zooplankton in the northern Barents Sea during Arctic spring,
Deep-Sea Res. Pt. II, 55, 2320–2329, https://doi.org/10.1016/j.dsr2.2008.05.006, 2008.
White, A. E., Foster, R. A., Benitez-Nelson, C. R., Masqué, P., Verdeny,
E., Popp, B. N., Arthur, K. E., and Prahl, F. G.: Nitrogen fixation in the
Gulf of California and the Eastern Tropical North Pacific, Prog. Oceanogr.,
109, 1–17, https://doi.org/10.1016/j.pocean.2012.09.002, 2012.
Zhang, X. and Dam, H. G.: Downward export of carbon by die1 migrant
mesozooplankton in the central equatorial Pacific, 44, 2191–2202, 1998.
Short summary
We performed N budgets to assess the role of N2 fixation on production and export in the western tropical South Pacific Ocean. We deployed a combination of techniques including high-sensitivity measurements of N input and sediment traps deployment. We demonstrated that N2 fixation was the major source of new N before atmospheric deposition and upward nitrate fluxes. It contributed significantly to organic matter export, indicating a high efficiency of this region to export carbon.
We performed N budgets to assess the role of N2 fixation on production and export in the western...
Altmetrics
Final-revised paper
Preprint