Articles | Volume 14, issue 1
https://doi.org/10.5194/bg-14-1-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/bg-14-1-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
02 Jan 2017
Research article |
| 02 Jan 2017
Ocean acidification impacts bacteria–phytoplankton coupling at low-nutrient conditions
Thomas Hornick
CORRESPONDING AUTHOR
Leibniz Institute of Freshwater Ecology and Inland
Fisheries (IGB), Experimental Limnology, 16775 Stechlin,
Germany
Lennart T. Bach
GEOMAR Helmholtz Centre for Ocean Research Kiel,
Düsternbrooker Weg 20, 24105 Kiel, Germany
Katharine J. Crawfurd
NIOZ Royal Netherlands Institute for Sea Research,
Department of Marine Microbiology and Biogeochemistry, and Utrecht
University, P.O. Box 59, 1790 AB Den Burg, Texel, the
Netherlands
Kristian Spilling
Marine Research Centre, Finnish Environment Institute,
P.O. Box 140, 00251 Helsinki, Finland
Tvärminne Zoological Station, University of Helsinki,
J. A. Palménin tie 260, 10900 Hanko, Finland
Eric P. Achterberg
GEOMAR Helmholtz Centre for Ocean Research Kiel,
Düsternbrooker Weg 20, 24105 Kiel, Germany
National Oceanography Centre Southampton, European Way,
University of Southampton, Southampton, SO14 3ZH, UK
Jason N. Woodhouse
Leibniz Institute of Freshwater Ecology and Inland
Fisheries (IGB), Experimental Limnology, 16775 Stechlin,
Germany
Kai G. Schulz
GEOMAR Helmholtz Centre for Ocean Research Kiel,
Düsternbrooker Weg 20, 24105 Kiel, Germany
Southern Cross University, P.O. Box 157, Lismore, NSW
2480, Australia
Corina P. D. Brussaard
NIOZ Royal Netherlands Institute for Sea Research,
Department of Marine Microbiology and Biogeochemistry, and Utrecht
University, P.O. Box 59, 1790 AB Den Burg, Texel, the
Netherlands
Aquatic Microbiology, Institute for Biodiversity and
Ecosystem Dynamics, University of Amsterdam, P.O. Box 94248, 1090 GE
Amsterdam, the Netherlands
Ulf Riebesell
GEOMAR Helmholtz Centre for Ocean Research Kiel,
Düsternbrooker Weg 20, 24105 Kiel, Germany
Hans-Peter Grossart
Leibniz Institute of Freshwater Ecology and Inland
Fisheries (IGB), Experimental Limnology, 16775 Stechlin,
Germany
Potsdam University, Institute for Biochemistry and
Biology, Maulbeerallee 2, 14469 Potsdam, Germany
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Librada Ramírez, Leonardo J. Pozzo-Pirotta, Aja Trebec, Víctor Manzanares-Vázquez, José L. Díez, Javier Arístegui, Ulf Riebesell, Stephen D. Archer, and María Segovia
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Ocean Alkalinity Enhancement (OAE) is an approach to sequester additional atmospheric CO2 in the ocean and may alleviate ocean acidification. A large-scale mesocosm experiment in Norway tested Ca- and Si-based OAE, increasing total alkalinity (TA) by 0–600 µmol kg-1 and measuring CO2 gas exchange. While TA remained stable, we found mineral-type and/or pCO2/pH effects on coccolithophorid calcification, net community production and zooplankton respiration, providing insights for future OAE trials.
Giulia Faucher, Mathias Haunost, Allanah Joy Paul, Anne Ulrike Christiane Tietz, and Ulf Riebesell
Biogeosciences, 22, 405–415, https://doi.org/10.5194/bg-22-405-2025, https://doi.org/10.5194/bg-22-405-2025, 2025
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Ocean alkalinity enhancement (OAE) is being evaluated for its capacity to absorb atmospheric CO2 in the ocean and store it long term to mitigate climate change. As researchers plan for field tests to gain insights into OAE, sharing knowledge on its environmental impact on marine ecosystems is urgent. Our study examined NaOH-induced OAE in Emiliania huxleyi, a key coccolithophore species, and found that the added total alkalinity (ΔTA) should stay below 600 µmol kg⁻¹ to avoid negative impacts.
Philipp Suessle, Jan Taucher, Silvan Urs Goldenberg, Moritz Baumann, Kristian Spilling, Andrea Noche-Ferreira, Mari Vanharanta, and Ulf Riebesell
Biogeosciences, 22, 71–86, https://doi.org/10.5194/bg-22-71-2025, https://doi.org/10.5194/bg-22-71-2025, 2025
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Ocean alkalinity enhancement (OAE) is a negative emission technology which may alter marine communities and the particle export they drive. Here, impacts of carbonate-based OAE on the flux and attenuation of sinking particles in an oligotrophic plankton community are presented. Whilst biological parameters remained unaffected, abiotic carbonate precipitation occurred. Among counteracting OAE’s efficiency, it influenced mineral ballasting and particle sinking velocities, requiring monitoring.
Laura Marín-Samper, Javier Arístegui, Nauzet Hernández-Hernández, and Ulf Riebesell
Biogeosciences, 21, 5707–5724, https://doi.org/10.5194/bg-21-5707-2024, https://doi.org/10.5194/bg-21-5707-2024, 2024
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This study exposed a natural community to two non-CO2-equilibrated ocean alkalinity enhancement (OAE) deployments using different minerals. Adding alkalinity in this manner decreases dissolved CO2, essential for photosynthesis. While photosynthesis was not suppressed, bloom formation was mildly delayed, potentially impacting marine food webs. The study emphasizes the need for further research on OAE without prior equilibration and on its ecological implications.
Jana Krause, Dustin Carroll, Juan Höfer, Jeremy Donaire, Eric P. Achterberg, Emilio Alarcón, Te Liu, Lorenz Meire, Kechen Zhu, and Mark J. Hopwood
The Cryosphere, 18, 5735–5752, https://doi.org/10.5194/tc-18-5735-2024, https://doi.org/10.5194/tc-18-5735-2024, 2024
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Here we analysed calved ice samples from both the Arctic and Antarctic to assess the variability in the composition of iceberg meltwater. Our results suggest that low concentrations of nitrate and phosphate in ice are primarily from the ice matrix, whereas sediment-rich layers impart a low concentration of silica and modest concentrations of iron and manganese. At a global scale, there are very limited differences in the nutrient composition of ice.
Charlotte Eich, Mathijs van Manen, J. Scott P. McCain, Loay J. Jabre, Willem H. van de Poll, Jinyoung Jung, Sven B. E. H. Pont, Hung-An Tian, Indah Ardiningsih, Gert-Jan Reichart, Erin M. Bertrand, Corina P. D. Brussaard, and Rob Middag
Biogeosciences, 21, 4637–4663, https://doi.org/10.5194/bg-21-4637-2024, https://doi.org/10.5194/bg-21-4637-2024, 2024
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Phytoplankton growth in the Southern Ocean (SO) is often limited by low iron (Fe) concentrations. Sea surface warming impacts Fe availability and can affect phytoplankton growth. We used shipboard Fe clean incubations to test how changes in Fe and temperature affect SO phytoplankton. Their abundances usually increased with Fe addition and temperature increase, with Fe being the major factor. These findings imply potential shifts in ecosystem structure, impacting food webs and elemental cycling.
Niels Suitner, Giulia Faucher, Carl Lim, Julieta Schneider, Charly A. Moras, Ulf Riebesell, and Jens Hartmann
Biogeosciences, 21, 4587–4604, https://doi.org/10.5194/bg-21-4587-2024, https://doi.org/10.5194/bg-21-4587-2024, 2024
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Recent studies described the precipitation of carbonates as a result of alkalinity enhancement in seawater, which could adversely affect the carbon sequestration potential of ocean alkalinity enhancement (OAE) approaches. By conducting experiments in natural seawater, this study observed uniform patterns during the triggered runaway carbonate precipitation, which allow the prediction of safe and efficient local application levels of OAE scenarios.
Silvan Urs Goldenberg, Ulf Riebesell, Daniel Brüggemann, Gregor Börner, Michael Sswat, Arild Folkvord, Maria Couret, Synne Spjelkavik, Nicolás Sánchez, Cornelia Jaspers, and Marta Moyano
Biogeosciences, 21, 4521–4532, https://doi.org/10.5194/bg-21-4521-2024, https://doi.org/10.5194/bg-21-4521-2024, 2024
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Ocean alkalinity enhancement (OAE) is being evaluated as a carbon dioxide removal technology for climate change mitigation. With an experiment on species communities, we show that larval and juvenile fish can be resilient to the resulting perturbation of seawater. Fish may hence recruit successfully and continue to support fisheries' production in regions of OAE. Our findings help to establish an environmentally safe operating space for this ocean-based solution.
Sebastian I. Cantarero, Edgart Flores, Harry Allbrook, Paulina Aguayo, Cristian A. Vargas, John E. Tamanaha, J. Bentley C. Scholz, Lennart T. Bach, Carolin R. Löscher, Ulf Riebesell, Balaji Rajagopalan, Nadia Dildar, and Julio Sepúlveda
Biogeosciences, 21, 3927–3958, https://doi.org/10.5194/bg-21-3927-2024, https://doi.org/10.5194/bg-21-3927-2024, 2024
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Our study explores lipid remodeling in response to environmental stress, specifically how cell membrane chemistry changes. We focus on intact polar lipids in a phytoplankton community exposed to diverse stressors in a mesocosm experiment. The observed remodeling indicates acyl chain recycling for energy storage in intact polar lipids during stress, reallocating resources based on varying growth conditions. This understanding is essential to grasp the system's impact on cellular pools.
Ingeborg Bussmann, Eric P. Achterberg, Holger Brix, Nicolas Brüggemann, Götz Flöser, Claudia Schütze, and Philipp Fischer
Biogeosciences, 21, 3819–3838, https://doi.org/10.5194/bg-21-3819-2024, https://doi.org/10.5194/bg-21-3819-2024, 2024
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Methane (CH4) is an important greenhouse gas and contributes to climate warming. However, the input of CH4 from coastal areas to the atmosphere is not well defined. Dissolved and atmospheric CH4 was determined at high spatial resolution in or above the North Sea. The atmospheric CH4 concentration was mainly influenced by wind direction. With our detailed study on the spatial distribution of CH4 fluxes we were able to provide a detailed and more realistic estimation of coastal CH4 fluxes.
Lennart Thomas Bach, Aaron James Ferderer, Julie LaRoche, and Kai Georg Schulz
Biogeosciences, 21, 3665–3676, https://doi.org/10.5194/bg-21-3665-2024, https://doi.org/10.5194/bg-21-3665-2024, 2024
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Ocean alkalinity enhancement (OAE) is an emerging marine CO2 removal method, but its environmental effects are insufficiently understood. The OAE Pelagic Impact Intercomparison Project (OAEPIIP) provides funding for a standardized and globally replicated microcosm experiment to study the effects of OAE on plankton communities. Here, we provide a detailed manual for the OAEPIIP experiment. We expect OAEPIIP to help build scientific consensus on the effects of OAE on plankton.
Charly A. Moras, Tyler Cyronak, Lennart T. Bach, Renaud Joannes-Boyau, and Kai G. Schulz
Biogeosciences, 21, 3463–3475, https://doi.org/10.5194/bg-21-3463-2024, https://doi.org/10.5194/bg-21-3463-2024, 2024
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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 sizes dissolved faster but calcium carbonate precipitated earlier, suggesting that medium grain sizes are optimal for kinetics.
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
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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.
Aaron Ferderer, Kai G. Schulz, Ulf Riebesell, Kirralee G. Baker, Zanna Chase, and Lennart T. Bach
Biogeosciences, 21, 2777–2794, https://doi.org/10.5194/bg-21-2777-2024, https://doi.org/10.5194/bg-21-2777-2024, 2024
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Ocean alkalinity enhancement (OAE) is a promising method of atmospheric carbon removal; however, its ecological impacts remain largely unknown. We assessed the effects of simulated silicate- and calcium-based mineral OAE on diatom silicification. We found that increased silicate concentrations from silicate-based OAE increased diatom silicification. In contrast, the enhancement of alkalinity had no effect on community silicification and minimal effects on the silicification of different genera.
David González-Santana, María Segovia, Melchor González-Dávila, Librada Ramírez, Aridane G. González, Leonardo J. Pozzo-Pirotta, Veronica Arnone, Victor Vázquez, Ulf Riebesell, and J. Magdalena Santana-Casiano
Biogeosciences, 21, 2705–2715, https://doi.org/10.5194/bg-21-2705-2024, https://doi.org/10.5194/bg-21-2705-2024, 2024
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In a recent experiment off the coast of Gran Canaria (Spain), scientists explored a method called ocean alkalinization enhancement (OAE), where carbonate minerals were added to seawater. This process changed the levels of certain ions in the water, affecting its pH and buffering capacity. The researchers were particularly interested in how this could impact the levels of essential trace metals in the water.
Jiaying A. Guo, Robert F. Strzepek, Kerrie M. Swadling, Ashley T. Townsend, and Lennart T. Bach
Biogeosciences, 21, 2335–2354, https://doi.org/10.5194/bg-21-2335-2024, https://doi.org/10.5194/bg-21-2335-2024, 2024
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Ocean alkalinity enhancement aims to increase atmospheric CO2 sequestration by adding alkaline materials to the ocean. We assessed the environmental effects of olivine and steel slag powder on coastal plankton. Overall, slag is more efficient than olivine in releasing total alkalinity and, thus, in its ability to sequester CO2. Slag also had less environmental effect on the enclosed plankton communities when considering its higher CO2 removal potential based on this 3-week experiment.
Allanah Joy Paul, Mathias Haunost, Silvan Urs Goldenberg, Jens Hartmann, Nicolás Sánchez, Julieta Schneider, Niels Suitner, and Ulf Riebesell
EGUsphere, https://doi.org/10.5194/egusphere-2024-417, https://doi.org/10.5194/egusphere-2024-417, 2024
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Ocean alkalinity enhancement (OAE) is being assessed for its potential to absorb atmospheric CO2 and store it for a long time. OAE still needs comprehensive assessment of its safety and effectiveness. We studied an idealised OAE application in a natural low nutrient ecosystem over one month. Our results showed that biogeochemical functioning remained mostly stable, but that the long-term capability for storing carbon may be limited at high alkalinity concentration.
Xiaoke Xin, Giulia Faucher, and Ulf Riebesell
Biogeosciences, 21, 761–772, https://doi.org/10.5194/bg-21-761-2024, https://doi.org/10.5194/bg-21-761-2024, 2024
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Ocean alkalinity enhancement (OAE) is a promising approach to remove CO2 by accelerating natural rock weathering. However, some of the alkaline substances contain trace metals which could be toxic to marine life. By exposing three representative phytoplankton species to Ni released from alkaline materials, we observed varying responses of phytoplankton to nickel concentrations, suggesting caution should be taken and toxic thresholds should be avoided in OAE with Ni-rich materials.
Lennart Thomas Bach
Biogeosciences, 21, 261–277, https://doi.org/10.5194/bg-21-261-2024, https://doi.org/10.5194/bg-21-261-2024, 2024
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Ocean alkalinity enhancement (OAE) is a widely considered marine carbon dioxide removal method. OAE aims to accelerate chemical rock weathering, which is a natural process that slowly sequesters atmospheric carbon dioxide. This study shows that the addition of anthropogenic alkalinity via OAE can reduce the natural release of alkalinity and, therefore, reduce the efficiency of OAE for climate mitigation. However, the additionality problem could be mitigated via a variety of activities.
David T. Ho, Laurent Bopp, Jaime B. Palter, Matthew C. Long, Philip W. Boyd, Griet Neukermans, and Lennart T. Bach
State Planet, 2-oae2023, 12, https://doi.org/10.5194/sp-2-oae2023-12-2023, https://doi.org/10.5194/sp-2-oae2023-12-2023, 2023
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Monitoring, reporting, and verification (MRV) refers to the multistep process to quantify the amount of carbon dioxide removed by a carbon dioxide removal (CDR) activity. Here, we make recommendations for MRV for Ocean Alkalinity Enhancement (OAE) research, arguing that it has an obligation for comprehensiveness, reproducibility, and transparency, as it may become the foundation for assessing large-scale deployment. Both observations and numerical simulations will be needed for MRV.
Tyler Cyronak, Rebecca Albright, and Lennart T. Bach
State Planet, 2-oae2023, 7, https://doi.org/10.5194/sp-2-oae2023-7-2023, https://doi.org/10.5194/sp-2-oae2023-7-2023, 2023
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Ocean alkalinity enhancement (OAE) is a marine carbon dioxide removal (CDR) approach. Publicly funded research projects have begun, and philanthropic funding and start-ups are collectively pushing the field forward. This rapid progress in research activities has created an urgent need to learn if and how OAE can work at scale. This chapter of the Guide to Best Practices in Ocean Alkalinity Enhancement Research focuses on field experiments.
Ulf Riebesell, Daniela Basso, Sonja Geilert, Andrew W. Dale, and Matthias Kreuzburg
State Planet, 2-oae2023, 6, https://doi.org/10.5194/sp-2-oae2023-6-2023, https://doi.org/10.5194/sp-2-oae2023-6-2023, 2023
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Mesocosm experiments represent a highly valuable tool in determining the safe operating space of ocean alkalinity enhancement (OAE) applications. By combining realism and biological complexity with controllability and replication, they provide an ideal OAE test bed and a critical stepping stone towards field applications. Mesocosm approaches can also be helpful in testing the efficacy, efficiency and permanence of OAE applications.
Kai G. Schulz, Lennart T. Bach, and Andrew G. Dickson
State Planet, 2-oae2023, 2, https://doi.org/10.5194/sp-2-oae2023-2-2023, https://doi.org/10.5194/sp-2-oae2023-2-2023, 2023
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Ocean alkalinity enhancement is a promising approach for long-term anthropogenic carbon dioxide sequestration, required to avoid catastrophic climate change. In this chapter we describe its impacts on seawater carbonate chemistry speciation and highlight pitfalls that need to be avoided during sampling, storage, measurements, and calculations.
Andreas Oschlies, Lennart T. Bach, Rosalind E. M. Rickaby, Terre Satterfield, Romany Webb, and Jean-Pierre Gattuso
State Planet, 2-oae2023, 1, https://doi.org/10.5194/sp-2-oae2023-1-2023, https://doi.org/10.5194/sp-2-oae2023-1-2023, 2023
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Reaching promised climate targets will require the deployment of carbon dioxide removal (CDR). Marine CDR options receive more and more interest. Based on idealized theoretical studies, ocean alkalinity enhancement (OAE) appears as a promising marine CDR method. We provide an overview on the current situation of developing OAE as a marine CDR method and describe the history that has led to the creation of the OAE research best practice guide.
Moritz Baumann, Allanah Joy Paul, Jan Taucher, Lennart Thomas Bach, Silvan Goldenberg, Paul Stange, Fabrizio Minutolo, and Ulf Riebesell
Biogeosciences, 20, 2595–2612, https://doi.org/10.5194/bg-20-2595-2023, https://doi.org/10.5194/bg-20-2595-2023, 2023
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The sinking velocity of marine particles affects how much atmospheric CO2 is stored inside our oceans. We measured particle sinking velocities in the Peruvian upwelling system and assessed their physical and biochemical drivers. We found that sinking velocity was mainly influenced by particle size and porosity, while ballasting minerals played only a minor role. Our findings help us to better understand the particle sinking dynamics in this highly productive marine system.
Kristian Spilling, Jonna Piiparinen, Eric P. Achterberg, Javier Arístegui, Lennart T. Bach, Maria T. Camarena-Gómez, Elisabeth von der Esch, Martin A. Fischer, Markel Gómez-Letona, Nauzet Hernández-Hernández, Judith Meyer, Ruth A. Schmitz, and Ulf Riebesell
Biogeosciences, 20, 1605–1619, https://doi.org/10.5194/bg-20-1605-2023, https://doi.org/10.5194/bg-20-1605-2023, 2023
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We carried out an enclosure experiment using surface water off Peru with different additions of oxygen minimum zone water. In this paper, we report on enzyme activity and provide data on the decomposition of organic matter. We found very high activity with respect to an enzyme breaking down protein, suggesting that this is important for nutrient recycling both at present and in the future ocean.
Markus A. Min, David M. Needham, Sebastian Sudek, Nathan Kobun Truelove, Kathleen J. Pitz, Gabriela M. Chavez, Camille Poirier, Bente Gardeler, Elisabeth von der Esch, Andrea Ludwig, Ulf Riebesell, Alexandra Z. Worden, and Francisco P. Chavez
Biogeosciences, 20, 1277–1298, https://doi.org/10.5194/bg-20-1277-2023, https://doi.org/10.5194/bg-20-1277-2023, 2023
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Emerging molecular methods provide new ways of understanding how marine communities respond to changes in ocean conditions. Here, environmental DNA was used to track the temporal evolution of biological communities in the Peruvian coastal upwelling system and in an adjacent enclosure where upwelling was simulated. We found that the two communities quickly diverged, with the open ocean being one found during upwelling and the enclosure evolving to one found under stratified conditions.
Jens Hartmann, Niels Suitner, Carl Lim, Julieta Schneider, Laura Marín-Samper, Javier Arístegui, Phil Renforth, Jan Taucher, and Ulf Riebesell
Biogeosciences, 20, 781–802, https://doi.org/10.5194/bg-20-781-2023, https://doi.org/10.5194/bg-20-781-2023, 2023
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CO2 can be stored in the ocean via increasing alkalinity of ocean water. Alkalinity can be created via dissolution of alkaline materials, like limestone or soda. Presented research studies boundaries for increasing alkalinity in seawater. The best way to increase alkalinity was found using an equilibrated solution, for example as produced from reactors. Adding particles for dissolution into seawater on the other hand produces the risk of losing alkalinity and degassing of CO2 to the atmosphere.
Allanah Joy Paul, Lennart Thomas Bach, Javier Arístegui, Elisabeth von der Esch, Nauzet Hernández-Hernández, Jonna Piiparinen, Laura Ramajo, Kristian Spilling, and Ulf Riebesell
Biogeosciences, 19, 5911–5926, https://doi.org/10.5194/bg-19-5911-2022, https://doi.org/10.5194/bg-19-5911-2022, 2022
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We investigated how different deep water chemistry and biology modulate the response of surface phytoplankton communities to upwelling in the Peruvian coastal zone. Our results show that the most influential drivers were the ratio of inorganic nutrients (N : P) and the microbial community present in upwelling source water. These led to unexpected and variable development in the phytoplankton assemblage that could not be predicted by the amount of inorganic nutrients alone.
Aaron Ferderer, Zanna Chase, Fraser Kennedy, Kai G. Schulz, and Lennart T. Bach
Biogeosciences, 19, 5375–5399, https://doi.org/10.5194/bg-19-5375-2022, https://doi.org/10.5194/bg-19-5375-2022, 2022
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Ocean alkalinity enhancement has the capacity to remove vast quantities of carbon from the atmosphere, but its effect on marine ecosystems is largely unknown. We assessed the effect of increased alkalinity on a coastal phytoplankton community when seawater was equilibrated and not equilibrated with atmospheric CO2. We found that the phytoplankton community was moderately affected by increased alkalinity and equilibration with atmospheric CO2 had little influence on this effect.
Jiaying Abby Guo, Robert Strzepek, Anusuya Willis, Aaron Ferderer, and Lennart Thomas Bach
Biogeosciences, 19, 3683–3697, https://doi.org/10.5194/bg-19-3683-2022, https://doi.org/10.5194/bg-19-3683-2022, 2022
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Ocean alkalinity enhancement is a CO2 removal method with significant potential, but it can lead to a perturbation of the ocean with trace metals such as nickel. This study tested the effect of increasing nickel concentrations on phytoplankton growth and photosynthesis. We found that the response to nickel varied across the 11 phytoplankton species tested here, but the majority were rather insensitive. We note, however, that responses may be different under other experimental conditions.
Charly A. Moras, Lennart T. Bach, Tyler Cyronak, Renaud Joannes-Boyau, and Kai G. Schulz
Biogeosciences, 19, 3537–3557, https://doi.org/10.5194/bg-19-3537-2022, https://doi.org/10.5194/bg-19-3537-2022, 2022
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This research presents the first laboratory results of quick and hydrated lime dissolution in natural seawater. These two minerals are of great interest for ocean alkalinity enhancement, a strategy aiming to decrease atmospheric CO2 concentrations. Following the dissolution of these minerals, we identified several hurdles and presented ways to avoid them or completely negate them. Finally, we proceeded to various simulations in today’s oceans to implement the strategy at its highest potential.
Bernhard Aichner, David Dubbert, Christine Kiel, Katrin Kohnert, Igor Ogashawara, Andreas Jechow, Sarah-Faye Harpenslager, Franz Hölker, Jens Christian Nejstgaard, Hans-Peter Grossart, Gabriel Singer, Sabine Wollrab, and Stella Angela Berger
Earth Syst. Sci. Data, 14, 1857–1867, https://doi.org/10.5194/essd-14-1857-2022, https://doi.org/10.5194/essd-14-1857-2022, 2022
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Water isotopes were measured along transects and in the form of time series in northeastern German lakes. The spatial patterns within the data and their seasonal variability are related to morphological and hydrological properties of the studied lake systems. They are further useful for the understanding of biogeochemical and ecological characteristics of these lakes.
Shao-Min Chen, Ulf Riebesell, Kai G. Schulz, Elisabeth von der Esch, Eric P. Achterberg, and Lennart T. Bach
Biogeosciences, 19, 295–312, https://doi.org/10.5194/bg-19-295-2022, https://doi.org/10.5194/bg-19-295-2022, 2022
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Oxygen minimum zones in the ocean are characterized by enhanced carbon dioxide (CO2) levels and are being further acidified by increasing anthropogenic atmospheric CO2. Here we report CO2 system measurements in a mesocosm study offshore Peru during a rare coastal El Niño event to investigate how CO2 dynamics may respond to ongoing ocean deoxygenation. Our observations show that nitrogen limitation, productivity, and plankton community shift play an important role in driving the CO2 dynamics.
Kai G. Schulz, Eric P. Achterberg, Javier Arístegui, Lennart T. Bach, Isabel Baños, Tim Boxhammer, Dirk Erler, Maricarmen Igarza, Verena Kalter, Andrea Ludwig, Carolin Löscher, Jana Meyer, Judith Meyer, Fabrizio Minutolo, Elisabeth von der Esch, Bess B. Ward, and Ulf Riebesell
Biogeosciences, 18, 4305–4320, https://doi.org/10.5194/bg-18-4305-2021, https://doi.org/10.5194/bg-18-4305-2021, 2021
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Upwelling of nutrient-rich deep waters to the surface make eastern boundary upwelling systems hot spots of marine productivity. This leads to subsurface oxygen depletion and the transformation of bioavailable nitrogen into inert N2. Here we quantify nitrogen loss processes following a simulated deep water upwelling. Denitrification was the dominant process, and budget calculations suggest that a significant portion of nitrogen that could be exported to depth is already lost in the surface ocean.
Neil J. Wyatt, Angela Milne, Eric P. Achterberg, Thomas J. Browning, Heather A. Bouman, E. Malcolm S. Woodward, and Maeve C. Lohan
Biogeosciences, 18, 4265–4280, https://doi.org/10.5194/bg-18-4265-2021, https://doi.org/10.5194/bg-18-4265-2021, 2021
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Using data collected during two expeditions to the South Atlantic Ocean, we investigated how the interaction between external sources and biological activity influenced the availability of the trace metals zinc and cobalt. This is important as both metals play essential roles in the metabolism and growth of phytoplankton and thus influence primary productivity of the oceans. We found seasonal changes in both processes that helped explain upper-ocean trace metal cycling.
Refat Abdel-Basset, Elhagag Ahmed Hasssan, and Hans-Peter Grossart
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-146, https://doi.org/10.5194/bg-2021-146, 2021
Manuscript not accepted for further review
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The aim of this work is to explore the ability of the cyanobacterium Dolichospermum flosaquae in microbially-induced calcium carbonate precipitation (MICP). Environmentally, MICP controls the availability of calcium, carbon and phosphorus in freshwater lakes and carbon exchange with the atmosphere. Citrate, at 4 mg/L, induced the highest carbonate alkalinity, the highest calcium consumption, the highest urease activity along with the lowest photosynthetic and respiratory oxygen exchange.
Maximiliano J. Vergara-Jara, Mark J. Hopwood, Thomas J. Browning, Insa Rapp, Rodrigo Torres, Brian Reid, Eric P. Achterberg, and José Luis Iriarte
Ocean Sci., 17, 561–578, https://doi.org/10.5194/os-17-561-2021, https://doi.org/10.5194/os-17-561-2021, 2021
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Ash from the Calbuco 2015 eruption spread across northern Patagonia, the SE Pacific and the SW Atlantic. In the Pacific, a phytoplankton bloom corresponded closely to the volcanic ash plume, suggesting that ash fertilized this region of the ocean. No such fertilization was found in the Atlantic where nutrients plausibly supplied by ash were likely already in excess of phytoplankton demand. In Patagonia, the May bloom was more intense than usual, but the mechanistic link to ash was less clear.
Michelle N. Simone, Kai G. Schulz, Joanne M. Oakes, and Bradley D. Eyre
Biogeosciences, 18, 1823–1838, https://doi.org/10.5194/bg-18-1823-2021, https://doi.org/10.5194/bg-18-1823-2021, 2021
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Estuaries are responsible for a large contribution of dissolved organic carbon (DOC) to the global C cycle, but it is unknown how this will change in the future. DOC fluxes from unvegetated sediments were investigated ex situ subject to conditions of warming and ocean acidification. The future climate shifted sediment fluxes from a slight DOC source to a significant sink, with global coastal DOC export decreasing by 80 %. This has global implications for C cycling and long-term C storage.
Yu-Te Hsieh, Walter Geibert, E. Malcolm S. Woodward, Neil J. Wyatt, Maeve C. Lohan, Eric P. Achterberg, and Gideon M. Henderson
Biogeosciences, 18, 1645–1671, https://doi.org/10.5194/bg-18-1645-2021, https://doi.org/10.5194/bg-18-1645-2021, 2021
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The South Atlantic near 40° S is one of the high-productivity and most dynamic nutrient regions in the oceans, but the sources and fluxes of trace elements (TEs) to this region remain unclear. This study investigates seawater Ra-228 and provides important constraints on ocean mixing and dissolved TE fluxes to this region. Vertical mixing is a more important source than aeolian or shelf inputs in this region, but particulate or winter deep-mixing inputs may be required to balance the TE budgets.
Hans van Haren, Corina P. D. Brussaard, Loes J. A. Gerringa, Mathijs H. van Manen, Rob Middag, and Ruud Groenewegen
Ocean Sci., 17, 301–318, https://doi.org/10.5194/os-17-301-2021, https://doi.org/10.5194/os-17-301-2021, 2021
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Changes in ocean temperature may affect vertical density stratification, which may hamper turbulent exchange and thus nutrient availability for phytoplankton growth. To quantify varying physical conditions, we sampled the upper 500 m along 17 ± 5° W between [30, 63]° N in summer. South to north, temperature decreased with stratification while turbulence and nutrient fluxes remained constant, likely due to internal waves breaking and little affected by the physical process of global warming.
Harriet L. Wilson, Ana I. Ayala, Ian D. Jones, Alec Rolston, Don Pierson, Elvira de Eyto, Hans-Peter Grossart, Marie-Elodie Perga, R. Iestyn Woolway, and Eleanor Jennings
Hydrol. Earth Syst. Sci., 24, 5559–5577, https://doi.org/10.5194/hess-24-5559-2020, https://doi.org/10.5194/hess-24-5559-2020, 2020
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Lakes are often described in terms of vertical layers. The
epilimnionrefers to the warm surface layer that is homogeneous due to mixing. The depth of the epilimnion can influence air–water exchanges and the vertical distribution of biological variables. We compared various methods for defining the epilimnion layer and found large variability between methods. Certain methods may be better suited for applications such as multi-lake comparison and assessing the impact of climate change.
Refat Abdel-Basset, Elhagag Ahmed Hassan, and Hans-Peter Grossart
Biogeosciences Discuss., https://doi.org/10.5194/bg-2020-378, https://doi.org/10.5194/bg-2020-378, 2020
Revised manuscript not accepted
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This work was planned and implemented to evaluate the capacity of the Cyanobacterium Dolichospermum flosaquae in microbially induced calcium carbonate precipitation (MICP), which in turn exerts numerous impacts in biogeochemistry of freshwater lakes. MICP is also a determinant of atmospheric carbon emission and eutrophication. Calcium citrate was the most inductive for MICP powered by photosynthesis. The results can be modeled for the implications of MICP in biogeochemical cycles of Ca, C & P.
Jan Lüdke, Marcus Dengler, Stefan Sommer, David Clemens, Sören Thomsen, Gerd Krahmann, Andrew W. Dale, Eric P. Achterberg, and Martin Visbeck
Ocean Sci., 16, 1347–1366, https://doi.org/10.5194/os-16-1347-2020, https://doi.org/10.5194/os-16-1347-2020, 2020
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We analyse the intraseasonal variability of the alongshore circulation off Peru in early 2017, this circulation is very important for the supply of nutrients to the upwelling regime. The causes of this variability and its impact on the biogeochemistry are investigated. The poleward flow is strengthened during the observed time period, likely by a downwelling coastal trapped wave. The stronger current causes an increase in nitrate and reduces the deficit of fixed nitrogen relative to phosphorus.
Ruifang C. Xie, Frédéric A. C. Le Moigne, Insa Rapp, Jan Lüdke, Beat Gasser, Marcus Dengler, Volker Liebetrau, and Eric P. Achterberg
Biogeosciences, 17, 4919–4936, https://doi.org/10.5194/bg-17-4919-2020, https://doi.org/10.5194/bg-17-4919-2020, 2020
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Thorium-234 (234Th) is widely used to study carbon fluxes from the surface ocean to depth. But few studies stress the relevance of oceanic advection and diffusion on the downward 234Th fluxes in nearshore environments. Our study in offshore Peru showed strong temporal variations in both the importance of physical processes on 234Th flux estimates and the oceanic residence time of 234Th, whereas salinity-derived seawater 238U activities accounted for up to 40 % errors in 234Th flux estimates.
Lennart Thomas Bach, Allanah Joy Paul, Tim Boxhammer, Elisabeth von der Esch, Michelle Graco, Kai Georg Schulz, Eric Achterberg, Paulina Aguayo, Javier Arístegui, Patrizia Ayón, Isabel Baños, Avy Bernales, Anne Sophie Boegeholz, Francisco Chavez, Gabriela Chavez, Shao-Min Chen, Kristin Doering, Alba Filella, Martin Fischer, Patricia Grasse, Mathias Haunost, Jan Hennke, Nauzet Hernández-Hernández, Mark Hopwood, Maricarmen Igarza, Verena Kalter, Leila Kittu, Peter Kohnert, Jesus Ledesma, Christian Lieberum, Silke Lischka, Carolin Löscher, Andrea Ludwig, Ursula Mendoza, Jana Meyer, Judith Meyer, Fabrizio Minutolo, Joaquin Ortiz Cortes, Jonna Piiparinen, Claudia Sforna, Kristian Spilling, Sonia Sanchez, Carsten Spisla, Michael Sswat, Mabel Zavala Moreira, and Ulf Riebesell
Biogeosciences, 17, 4831–4852, https://doi.org/10.5194/bg-17-4831-2020, https://doi.org/10.5194/bg-17-4831-2020, 2020
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The eastern boundary upwelling system off Peru is among Earth's most productive ocean ecosystems, but the factors that control its functioning are poorly constrained. Here we used mesocosms, moored ~ 6 km offshore Peru, to investigate how processes in plankton communities drive key biogeochemical processes. We show that nutrient and light co-limitation keep productivity and export at a remarkably constant level while stoichiometry changes strongly with shifts in plankton community structure.
Stacy Deppeler, Kai G. Schulz, Alyce Hancock, Penelope Pascoe, John McKinlay, and Andrew Davidson
Biogeosciences, 17, 4153–4171, https://doi.org/10.5194/bg-17-4153-2020, https://doi.org/10.5194/bg-17-4153-2020, 2020
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Our study showed how ocean acidification can exert both direct and indirect influences on the interactions among trophic levels within the microbial loop. Microbial grazer abundance was reduced at CO2 concentrations at and above 634 µatm, while microbial communities increased in abundance, likely due to a reduction in being grazed. Such changes in predator–prey interactions with ocean acidification could have significant effects on the food web and biogeochemistry in the Southern Ocean.
Shangbin Xiao, Liu Liu, Wei Wang, Andreas Lorke, Jason Woodhouse, and Hans-Peter Grossart
Hydrol. Earth Syst. Sci., 24, 3871–3880, https://doi.org/10.5194/hess-24-3871-2020, https://doi.org/10.5194/hess-24-3871-2020, 2020
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To better understand the fate of methane (CH4) and carbon dioxide (CO2) in freshwaters, dissolved CH4 and CO2 need to be measured with a high temporal resolution. We developed the Fast-Response Automated Gas Equilibrator (FaRAGE) for real-time in situ measurement of dissolved gases in water. FaRAGE can achieve a short response time (CH4:
t95 % = 12 s; CO2:
t95 % = 10 s) while retaining a high equilibration ratio and accuracy.
Anna Plass, Christian Schlosser, Stefan Sommer, Andrew W. Dale, Eric P. Achterberg, and Florian Scholz
Biogeosciences, 17, 3685–3704, https://doi.org/10.5194/bg-17-3685-2020, https://doi.org/10.5194/bg-17-3685-2020, 2020
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We compare the cycling of Fe and Cd in sulfidic sediments of the Peruvian oxygen minimum zone. Due to the contrasting solubility of their sulfide minerals, the sedimentary Fe release and Cd burial fluxes covary with spatial and temporal distributions of H2S. Depending on the solubility of their sulfide minerals, sedimentary trace metal fluxes will respond differently to ocean deoxygenation/expansion of H2S concentrations, which may change trace metal stoichiometry of upwelling water masses.
Giulia Faucher, Ulf Riebesell, and Lennart Thomas Bach
Clim. Past, 16, 1007–1025, https://doi.org/10.5194/cp-16-1007-2020, https://doi.org/10.5194/cp-16-1007-2020, 2020
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We designed five experiments choosing different coccolithophore species that have been evolutionarily distinct for millions of years. If all species showed the same morphological response to an environmental driver, this could be indicative of a response pattern that is conserved over geological timescales. We found an increase in the percentage of malformed coccoliths under altered CO2, providing evidence that this response could be used as paleo-proxy for episodes of acute CO2 perturbations.
Mark J. Hopwood, Dustin Carroll, Thorben Dunse, Andy Hodson, Johnna M. Holding, José L. Iriarte, Sofia Ribeiro, Eric P. Achterberg, Carolina Cantoni, Daniel F. Carlson, Melissa Chierici, Jennifer S. Clarke, Stefano Cozzi, Agneta Fransson, Thomas Juul-Pedersen, Mie H. S. Winding, and Lorenz Meire
The Cryosphere, 14, 1347–1383, https://doi.org/10.5194/tc-14-1347-2020, https://doi.org/10.5194/tc-14-1347-2020, 2020
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Here we compare and contrast results from five well-studied Arctic field sites in order to understand how glaciers affect marine biogeochemistry and marine primary production. The key questions are listed as follows. Where and when does glacial freshwater discharge promote or reduce marine primary production? How does spatio-temporal variability in glacial discharge affect marine primary production? And how far-reaching are the effects of glacial discharge on marine biogeochemistry?
Claudia Frey, Hermann W. Bange, Eric P. Achterberg, Amal Jayakumar, Carolin R. Löscher, Damian L. Arévalo-Martínez, Elizabeth León-Palmero, Mingshuang Sun, Xin Sun, Ruifang C. Xie, Sergey Oleynik, and Bess B. Ward
Biogeosciences, 17, 2263–2287, https://doi.org/10.5194/bg-17-2263-2020, https://doi.org/10.5194/bg-17-2263-2020, 2020
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The production of N2O via nitrification and denitrification associated with low-O2 waters is a major source of oceanic N2O. We investigated the regulation and dynamics of these processes with respect to O2 and organic matter inputs. The transcription of the key nitrification gene amoA rapidly responded to changes in O2 and strongly correlated with N2O production rates. N2O production by denitrification was clearly stimulated by organic carbon, implying that its supply controls N2O production.
Mark J. Hopwood, Nicolas Sanchez, Despo Polyviou, Øystein Leiknes, Julián Alberto Gallego-Urrea, Eric P. Achterberg, Murat V. Ardelan, Javier Aristegui, Lennart Bach, Sengul Besiktepe, Yohann Heriot, Ioanna Kalantzi, Tuba Terbıyık Kurt, Ioulia Santi, Tatiana M. Tsagaraki, and David Turner
Biogeosciences, 17, 1309–1326, https://doi.org/10.5194/bg-17-1309-2020, https://doi.org/10.5194/bg-17-1309-2020, 2020
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Hydrogen peroxide, H2O2, is formed naturally in sunlight-exposed water by photochemistry. At high concentrations it is undesirable to biological cells because it is a stressor. Here, across a range of incubation experiments in diverse marine environments (Gran Canaria, the Mediterranean, Patagonia and Svalbard), we determine that two factors consistently affect the H2O2 concentrations irrespective of geographical location: bacteria abundance and experiment design.
Mark J. Hopwood, Carolina Santana-González, Julian Gallego-Urrea, Nicolas Sanchez, Eric P. Achterberg, Murat V. Ardelan, Martha Gledhill, Melchor González-Dávila, Linn Hoffmann, Øystein Leiknes, Juana Magdalena Santana-Casiano, Tatiana M. Tsagaraki, and David Turner
Biogeosciences, 17, 1327–1342, https://doi.org/10.5194/bg-17-1327-2020, https://doi.org/10.5194/bg-17-1327-2020, 2020
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Fe is an essential micronutrient. Fe(III)-organic species are thought to account for > 99 % of dissolved Fe in seawater. Here we quantified Fe(II) during experiments in Svalbard, Gran Canaria, and Patagonia. Fe(II) was always a measurable fraction of dissolved Fe up to 65 %. Furthermore, when Fe(II) was allowed to decay in the dark, it remained present longer than predicted by kinetic equations, suggesting that Fe(II) is a more important fraction of dissolved Fe in seawater than widely recognized.
Insa Rapp, Christian Schlosser, Jan-Lukas Menzel Barraqueta, Bernhard Wenzel, Jan Lüdke, Jan Scholten, Beat Gasser, Patrick Reichert, Martha Gledhill, Marcus Dengler, and Eric P. Achterberg
Biogeosciences, 16, 4157–4182, https://doi.org/10.5194/bg-16-4157-2019, https://doi.org/10.5194/bg-16-4157-2019, 2019
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The availability of iron (Fe) affects phytoplankton growth in large parts of the ocean. Shelf sediments, particularly in oxygen minimum zones, are a major source of Fe and other essential micronutrients, such as cobalt (Co) and manganese (Mn). We observed enhanced concentrations of Fe, Co, and Mn corresponding with low oxygen concentrations along the Mauritanian shelf, indicating that the projected future decrease in oxygen concentrations may result in increases in Fe, Mn, and Co concentrations.
Lennart Thomas Bach and Jan Taucher
Ocean Sci., 15, 1159–1175, https://doi.org/10.5194/os-15-1159-2019, https://doi.org/10.5194/os-15-1159-2019, 2019
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Diatoms are a group of phytoplankton species responsible for ~ 25 % of primary production on Earth. Ocean acidification (OA) could influence diatoms but the key question is if they become more or less important within marine food webs. We synthesize OA experiments with natural communities and found that diatoms are more likely to be positively than negatively affected by high CO2 and larger species may profit in particular. This has important implications for ecosystem services diatoms provide.
Jan-Lukas Menzel Barraqueta, Jessica K. Klar, Martha Gledhill, Christian Schlosser, Rachel Shelley, Hélène F. Planquette, Bernhard Wenzel, Geraldine Sarthou, and Eric P. Achterberg
Biogeosciences, 16, 1525–1542, https://doi.org/10.5194/bg-16-1525-2019, https://doi.org/10.5194/bg-16-1525-2019, 2019
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We used surface water dissolved aluminium concentrations collected in four different GEOTRACES cruises to determine atmospheric deposition fluxes to the ocean. We calculate atmospheric deposition fluxes for largely under-sampled regions of the Atlantic Ocean and thus provide new constraints for models of atmospheric deposition. The use of the MADCOW model is of major importance as dissolved aluminium is analysed within the GEOTRACES project at high spatial resolution.
Laura F. Korte, Franziska Pausch, Scarlett Trimborn, Corina P. D. Brussaard, Geert-Jan A. Brummer, Michèlle van der Does, Catarina V. Guerreiro, Laura T. Schreuder, Chris I. Munday, and Jan-Berend W. Stuut
Biogeosciences Discuss., https://doi.org/10.5194/bg-2018-484, https://doi.org/10.5194/bg-2018-484, 2018
Revised manuscript not accepted
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This paper shows the differences of nutrient release after dry and wet Saharan dust deposition in the tropical North Atlantic Ocean at 12° N. Incubation experiments were conducted along an east-west transect. Large differences were observed between both deposition types with wet deposition being the dominant source of phosphate, silicate, and iron. Both deposition types suggest that Saharan dust particles might be incorporated into marine snow aggregates and act as ballast mineral.
Géraldine Sarthou, Pascale Lherminier, Eric P. Achterberg, Fernando Alonso-Pérez, Eva Bucciarelli, Julia Boutorh, Vincent Bouvier, Edward A. Boyle, Pierre Branellec, Lidia I. Carracedo, Nuria Casacuberta, Maxi Castrillejo, Marie Cheize, Leonardo Contreira Pereira, Daniel Cossa, Nathalie Daniault, Emmanuel De Saint-Léger, Frank Dehairs, Feifei Deng, Floriane Desprez de Gésincourt, Jérémy Devesa, Lorna Foliot, Debany Fonseca-Batista, Morgane Gallinari, Maribel I. García-Ibáñez, Arthur Gourain, Emilie Grossteffan, Michel Hamon, Lars Eric Heimbürger, Gideon M. Henderson, Catherine Jeandel, Catherine Kermabon, François Lacan, Philippe Le Bot, Manon Le Goff, Emilie Le Roy, Alison Lefèbvre, Stéphane Leizour, Nolwenn Lemaitre, Pere Masqué, Olivier Ménage, Jan-Lukas Menzel Barraqueta, Herlé Mercier, Fabien Perault, Fiz F. Pérez, Hélène F. Planquette, Frédéric Planchon, Arnout Roukaerts, Virginie Sanial, Raphaëlle Sauzède, Catherine Schmechtig, Rachel U. Shelley, Gillian Stewart, Jill N. Sutton, Yi Tang, Nadine Tisnérat-Laborde, Manon Tonnard, Paul Tréguer, Pieter van Beek, Cheryl M. Zurbrick, and Patricia Zunino
Biogeosciences, 15, 7097–7109, https://doi.org/10.5194/bg-15-7097-2018, https://doi.org/10.5194/bg-15-7097-2018, 2018
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The GEOVIDE cruise (GEOTRACES Section GA01) was conducted in the North Atlantic Ocean and Labrador Sea in May–June 2014. In this special issue, results from GEOVIDE, including physical oceanography and trace element and isotope cyclings, are presented among 17 articles. Here, the scientific context, project objectives, and scientific strategy of GEOVIDE are provided, along with an overview of the main results from the articles published in the special issue.
Sergio Balzano, Julie Lattaud, Laura Villanueva, Sebastiaan W. Rampen, Corina P. D. Brussaard, Judith van Bleijswijk, Nicole Bale, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 5951–5968, https://doi.org/10.5194/bg-15-5951-2018, https://doi.org/10.5194/bg-15-5951-2018, 2018
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We tried to identify the microbes which biosynthesize a class of lipids widespread in seawater, the long chain alkyl diols (LCDs). We could not find any microorganism likely involved in the production of LCDs. The amounts of LCDs found are too high to be produced by living organisms and are likely to be part of the refractory organic matter persisting for long periods in the water column.
Jan-Lukas Menzel Barraqueta, Christian Schlosser, Hélène Planquette, Arthur Gourain, Marie Cheize, Julia Boutorh, Rachel Shelley, Leonardo Contreira Pereira, Martha Gledhill, Mark J. Hopwood, François Lacan, Pascale Lherminier, Geraldine Sarthou, and Eric P. Achterberg
Biogeosciences, 15, 5271–5286, https://doi.org/10.5194/bg-15-5271-2018, https://doi.org/10.5194/bg-15-5271-2018, 2018
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In the North Atlantic and Labrador Sea, low aerosol deposition and enhanced primary productivity control the dissolved aluminium (dAl) surface distribution, while remineralization of particles seems to control the distribution at depth. DAl in the ocean allows us to indirectly quantify the amount of dust deposited to a given region for a given period. Hence, the study of its distribution, cycling, sources, and sinks is of major importance to improve aerosol deposition models and climate models.
Christian Schlosser, Katrin Schmidt, Alfred Aquilina, William B. Homoky, Maxi Castrillejo, Rachel A. Mills, Matthew D. Patey, Sophie Fielding, Angus Atkinson, and Eric P. Achterberg
Biogeosciences, 15, 4973–4993, https://doi.org/10.5194/bg-15-4973-2018, https://doi.org/10.5194/bg-15-4973-2018, 2018
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Iron (Fe) emanating from the South Georgia shelf system fuels large phytoplankton blooms downstream of the island. However, the actual supply mechanisms of Fe are unclear. We found that shelf-sediment-derived iron and iron released from Antarctic krill control the Fe distribution in the shelf waters around South Georgia. The majority of the Fe appears to be derived from recycling of Fe-enriched particles that are transported with the water masses into the bloom region.
Yong Zhang, Lennart T. Bach, Kai T. Lohbeck, Kai G. Schulz, Luisa Listmann, Regina Klapper, and Ulf Riebesell
Biogeosciences, 15, 3691–3701, https://doi.org/10.5194/bg-15-3691-2018, https://doi.org/10.5194/bg-15-3691-2018, 2018
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To compare variations in physiological responses to pCO2 between populations, we measured growth, POC and PIC production rates at a pCO2 range from 120 to 2630 µatm for 17 strains of the coccolithophore Emiliania huxleyi from the Azores, Canary Islands, and Norwegian coast near Bergen. Optimal pCO2 for growth and POC production rates and tolerance to low pH was significantly higher for the Bergen population than the Azores and Canary Islands populations.
Natasha A. Gafar and Kai G. Schulz
Biogeosciences, 15, 3541–3560, https://doi.org/10.5194/bg-15-3541-2018, https://doi.org/10.5194/bg-15-3541-2018, 2018
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Emiliania huxleyi and Gephyrocapsa oceanica are the most prolific calcifying phytoplankton in today's oceans. We compare their sensitivity to combined anthropogenic stressors of temperature, light and CO2. For the future, we project a niche contraction for G. oceanica. Furthermore, there was good correlation of our new metric, the CaCO3 production potential, with satellite-derived concentrations in the modern ocean, indicating means of assessing overall coccolithophorid success in the future.
Alyce M. Hancock, Andrew T. Davidson, John McKinlay, Andrew McMinn, Kai G. Schulz, and Rick L. van den Enden
Biogeosciences, 15, 2393–2410, https://doi.org/10.5194/bg-15-2393-2018, https://doi.org/10.5194/bg-15-2393-2018, 2018
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Absorption of carbon dioxide (CO2) realized by humans is decreasing the ocean pH (ocean acidification). Single-celled organisms (microbes) support the Antarctic ecosystem, yet little is known about their sensitivity to ocean acidification. This study shows a shift in a natural Antarctic microbial community, with CO2 levels exceeding 634 μatm changing the community composition and favouring small cells. This would have significant flow effects for Antarctic food webs and elemental cycles.
Nicole J. Bale, Tracy A. Villareal, Ellen C. Hopmans, Corina P. D. Brussaard, Marc Besseling, Denise Dorhout, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 1229–1241, https://doi.org/10.5194/bg-15-1229-2018, https://doi.org/10.5194/bg-15-1229-2018, 2018
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Associations between diatoms and N-fixing cyanobacteria (diatom–diazotroph associations, DDAs) play an important role in the N cycle of the tropical North Atlantic. Heterocysts are the site of N fixation and contain unique glycolipids. We measured these glycolipids in the water column and surface sediment from the tropical North Atlantic. We found a significant correlation between the concentration of glycolipid and of DDAs, strengthening their application as biomarkers.
Stacy Deppeler, Katherina Petrou, Kai G. Schulz, Karen Westwood, Imojen Pearce, John McKinlay, and Andrew Davidson
Biogeosciences, 15, 209–231, https://doi.org/10.5194/bg-15-209-2018, https://doi.org/10.5194/bg-15-209-2018, 2018
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We combined productivity and photophysiology measurements to investigate the effects of ocean acidification on a natural Antarctic marine microbial community. Our study identifies a threshold for CO2 tolerance in the phytoplankton community between 953 and 1140 μatm of CO2, above which productivity declines. Bacteria were tolerant to CO2 up to 1641 μatm. We identify physiological changes in the phytoplankton at high CO2 that allowed them to acclimate to the high CO2 treatment.
Coulson A. Lantz, Kai G. Schulz, Laura Stoltenberg, and Bradley D. Eyre
Biogeosciences, 14, 5377–5391, https://doi.org/10.5194/bg-14-5377-2017, https://doi.org/10.5194/bg-14-5377-2017, 2017
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This study examined the combined effect of seawater warming and organic matter enrichment on coral reef sediment metabolism. Sediments under control conditions were net autotrophic and net calcifying. Warming shifted the sediment to net heterotrophy and net dissolution, while organic matter enrichment increased net production and net calcification. When combined, the effects of each treatment were counterbalanced and sediment metabolism did not significantly differ from control treatments.
Katharine J. Crawfurd, Santiago Alvarez-Fernandez, Kristina D. A. Mojica, Ulf Riebesell, and Corina P. D. Brussaard
Biogeosciences, 14, 3831–3849, https://doi.org/10.5194/bg-14-3831-2017, https://doi.org/10.5194/bg-14-3831-2017, 2017
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Carbon dioxide (CO2) is increasing in the atmosphere and oceans. To simulate future conditions we manipulated CO2 concentrations of natural Baltic seawater in 55 m3 bags in situ. We saw increased growth rates and abundances of the smallest-sized eukaryotic phytoplankton and reduced abundances of other phytoplankton with increased CO2. Viral and bacterial abundances were also affected. This would lead to more carbon recycling in the surface water and affect marine food webs and the carbon cycle.
Giulia Faucher, Linn Hoffmann, Lennart T. Bach, Cinzia Bottini, Elisabetta Erba, and Ulf Riebesell
Biogeosciences, 14, 3603–3613, https://doi.org/10.5194/bg-14-3603-2017, https://doi.org/10.5194/bg-14-3603-2017, 2017
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The main goal of this study was to understand if, similarly to the fossil record, high quantities of toxic metals induce coccolith dwarfism in coccolithophore species. We investigated, for the first time, the effects of trace metals on coccolithophore species other than E. huxleyi and on coccolith morphology and size. Our data show a species-specific sensitivity to trace metal concentration, allowing the recognition of the most-, intermediate- and least-tolerant taxa to trace metal enrichments.
Hanieh T. Farid, Kai G. Schulz, and Andrew L. Rose
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-129, https://doi.org/10.5194/bg-2017-129, 2017
Manuscript not accepted for further review
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This study provides new insights into: (a) how organic exudates from a marine cyanobacterium may influence iron speciation and bioavailability in the extracellular milieu; and (b) approaches for evaluating rate constants for Fe(II) oxidation in the presence of unknown organic ligands. Given that microorganisms play critical roles in biochemical cycling of trace metals in water systems, the findings are expected to improve nutrient uptake models and be of interest to broad range of readers.
Mitchell Call, Kai G. Schulz, Matheus C. Carvalho, Isaac R. Santos, and Damien T. Maher
Biogeosciences, 14, 1305–1313, https://doi.org/10.5194/bg-14-1305-2017, https://doi.org/10.5194/bg-14-1305-2017, 2017
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The conventional method for determining dissolved inorganic carbon (DIC) and it carbon stable isotope ratio (δ13C–DIC) can be a laborious process which can limit sampling frequency. This paper presents a new approach to autonomously determine DIC & δ13C–DIC at high temporal resolution. The simple method requires no customised design. Instead it uses two commercially available instruments and achieved a sampling resolution of 16 mins with precision and accuracy comparable to conventional methods.
Silke Lischka, Lennart T. Bach, Kai-Georg Schulz, and Ulf Riebesell
Biogeosciences, 14, 447–466, https://doi.org/10.5194/bg-14-447-2017, https://doi.org/10.5194/bg-14-447-2017, 2017
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We conducted a large-scale field experiment using 55 m3 floating containers (mesocosms) to investigate consequences of near-future projected CO2 elevations (ocean acidification) on a Baltic Sea plankton community in Storfjärden (Finland). The focus of our study was on single- and multicelled small-sized organisms dwelling in the water column. Our results suggest that increasing CO2 concentrations may change the species composition and promote specific food web interactions.
Enis Hrustić, Risto Lignell, Ulf Riebesell, and Tron Frede Thingstad
Biogeosciences, 14, 379–387, https://doi.org/10.5194/bg-14-379-2017, https://doi.org/10.5194/bg-14-379-2017, 2017
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Phytoplankton in the ocean's stratified layer are limited by mineral nutrients, normally nitrogen, phosphorus, or iron. It is important to know not only which element is limiting, but also the surplus of the secondary limiting element. We explore here, in temperate mesotrophic waters, a bioassay based on alkaline phosphatase that provides information on both of these.
Rafael Bermúdez, Monika Winder, Annegret Stuhr, Anna-Karin Almén, Jonna Engström-Öst, and Ulf Riebesell
Biogeosciences, 13, 6625–6635, https://doi.org/10.5194/bg-13-6625-2016, https://doi.org/10.5194/bg-13-6625-2016, 2016
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Increasing CO2 is changing seawater chemistry towards a lower pH, which affects marine organisms. We investigate the response of a brackish plankton community to a CO2 gradient in terms of structure and fatty acid composition. The structure was resilient to CO2 and did not diverge between treatments. FA was influenced by community structure, which was driven by silicate and phosphate. This suggests that CO2 effects are dampened in communities already experiencing high natural pCO2 fluctuation.
Anu Vehmaa, Anna-Karin Almén, Andreas Brutemark, Allanah Paul, Ulf Riebesell, Sara Furuhagen, and Jonna Engström-Öst
Biogeosciences, 13, 6171–6182, https://doi.org/10.5194/bg-13-6171-2016, https://doi.org/10.5194/bg-13-6171-2016, 2016
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Ocean acidification is challenging phenotypic plasticity of individuals and populations. We studied phenotypic plasticity of the calanoid copepod Acartia bifilosa in the course of a pelagic, large-volume mesocosm study in the Baltic Sea. We found significant negative effects of ocean acidification on adult female copepod size and egg hatching success. Overall, these results indicate that A. bifilosa could be affected by projected near-future CO2 levels.
Kristian Spilling, Kai G. Schulz, Allanah J. Paul, Tim Boxhammer, Eric P. Achterberg, Thomas Hornick, Silke Lischka, Annegret Stuhr, Rafael Bermúdez, Jan Czerny, Kate Crawfurd, Corina P. D. Brussaard, Hans-Peter Grossart, and Ulf Riebesell
Biogeosciences, 13, 6081–6093, https://doi.org/10.5194/bg-13-6081-2016, https://doi.org/10.5194/bg-13-6081-2016, 2016
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We performed an experiment in the Baltic Sea in order to investigate the consequences of the increasing CO2 levels on biological processes in the free water mass. There was more accumulation of organic carbon at high CO2 levels. Surprisingly, this was caused by reduced loss processes (respiration and bacterial production) in a high-CO2 environment, and not by increased photosynthetic fixation of CO2. Our carbon budget can be used to better disentangle the effects of ocean acidification.
Francesca Gallo, Kai G. Schulz, Eduardo B. Azevedo, João Madruga, and Joana Barcelos e Ramos
Biogeosciences Discuss., https://doi.org/10.5194/bg-2016-352, https://doi.org/10.5194/bg-2016-352, 2016
Revised manuscript not accepted
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Global change driven by humans activities may affect phytoplankton, which are important primary producers. Assessing the combined effect of turbulence and ocean acidification on the species Asterionellopsis glacialis, we found that turbulence magnifies the acidification stress, with negative effects on their growth. In the natural environment, this might have consequences to phytoplankton community composition and production with feedbacks to climate.
Kristian Spilling, Allanah J. Paul, Niklas Virkkala, Tom Hastings, Silke Lischka, Annegret Stuhr, Rafael Bermúdez, Jan Czerny, Tim Boxhammer, Kai G. Schulz, Andrea Ludwig, and Ulf Riebesell
Biogeosciences, 13, 4707–4719, https://doi.org/10.5194/bg-13-4707-2016, https://doi.org/10.5194/bg-13-4707-2016, 2016
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Anthropogenic carbon dioxide (CO2) emissions are reducing the pH in the world's oceans. We determined the plankton community composition and measured primary production, respiration rates and carbon export during an ocean acidification experiment. Our results suggest that increased CO2 reduced respiration and increased net carbon fixation at high CO2. This did not, however, translate into higher carbon export, and consequently did not work as a negative feedback mechanism for decreasing pH.
Juntian Xu, Lennart T. Bach, Kai G. Schulz, Wenyan Zhao, Kunshan Gao, and Ulf Riebesell
Biogeosciences, 13, 4637–4643, https://doi.org/10.5194/bg-13-4637-2016, https://doi.org/10.5194/bg-13-4637-2016, 2016
Alison L. Webb, Emma Leedham-Elvidge, Claire Hughes, Frances E. Hopkins, Gill Malin, Lennart T. Bach, Kai Schulz, Kate Crawfurd, Corina P. D. Brussaard, Annegret Stuhr, Ulf Riebesell, and Peter S. Liss
Biogeosciences, 13, 4595–4613, https://doi.org/10.5194/bg-13-4595-2016, https://doi.org/10.5194/bg-13-4595-2016, 2016
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This paper presents concentrations of several trace gases produced by the Baltic Sea phytoplankton community during a mesocosm experiment with five different CO2 levels. Average concentrations of dimethylsulphide were lower in the highest CO2 mesocosms over a 6-week period, corresponding to previous mesocosm experiment results. No dimethylsulfoniopropionate was detected due to a methodological issue. Concentrations of iodine- and bromine-containing halocarbons were unaffected by increasing CO2.
Allanah J. Paul, Eric P. Achterberg, Lennart T. Bach, Tim Boxhammer, Jan Czerny, Mathias Haunost, Kai-Georg Schulz, Annegret Stuhr, and Ulf Riebesell
Biogeosciences, 13, 3901–3913, https://doi.org/10.5194/bg-13-3901-2016, https://doi.org/10.5194/bg-13-3901-2016, 2016
Carolin R. Löscher, Hermann W. Bange, Ruth A. Schmitz, Cameron M. Callbeck, Anja Engel, Helena Hauss, Torsten Kanzow, Rainer Kiko, Gaute Lavik, Alexandra Loginova, Frank Melzner, Judith Meyer, Sven C. Neulinger, Markus Pahlow, Ulf Riebesell, Harald Schunck, Sören Thomsen, and Hannes Wagner
Biogeosciences, 13, 3585–3606, https://doi.org/10.5194/bg-13-3585-2016, https://doi.org/10.5194/bg-13-3585-2016, 2016
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The ocean loses oxygen due to climate change. Addressing this issue in tropical ocean regions (off Peru and Mauritania), we aimed to understand the effects of oxygen depletion on various aspects of marine biogeochemistry, including primary production and export production, the nitrogen cycle, greenhouse gas production, organic matter fluxes and remineralization, and the role of zooplankton and viruses.
Anna Jansson, Silke Lischka, Tim Boxhammer, Kai G. Schulz, and Joanna Norkko
Biogeosciences, 13, 3377–3385, https://doi.org/10.5194/bg-13-3377-2016, https://doi.org/10.5194/bg-13-3377-2016, 2016
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We studied the responses of larvae of Macoma balthica to a range of future CO2 scenarios using large mesocosms encompassing the entire pelagic community. We focused on the growth and settlement process of M. balthica when exposed to future CO2 levels, and found the size and time to settlement to increase along the CO2 gradient, suggesting a developmental delay. The strong impact of increasing CO2 on early-stage bivalves is alarming as these stages are crucial for sustaining viable populations.
Matthew P. Humphreys, Florence M. Greatrix, Eithne Tynan, Eric P. Achterberg, Alex M. Griffiths, Claudia H. Fry, Rebecca Garley, Alison McDonald, and Adrian J. Boyce
Earth Syst. Sci. Data, 8, 221–233, https://doi.org/10.5194/essd-8-221-2016, https://doi.org/10.5194/essd-8-221-2016, 2016
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This paper reports the stable isotope composition of dissolved inorganic carbon in seawater for a transect from west to east across the North Atlantic Ocean. The results can be used to study oceanic uptake of anthropogenic carbon dioxide, and also to investigate the natural biological carbon pump. We also provide stable DIC isotope results for two batches of Dickson seawater CRMs to enable intercomparisons with other studies.
Monika Nausch, Lennart Thomas Bach, Jan Czerny, Josephine Goldstein, Hans-Peter Grossart, Dana Hellemann, Thomas Hornick, Eric Pieter Achterberg, Kai-Georg Schulz, and Ulf Riebesell
Biogeosciences, 13, 3035–3050, https://doi.org/10.5194/bg-13-3035-2016, https://doi.org/10.5194/bg-13-3035-2016, 2016
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Studies investigating the effect of increasing CO2 levels on the phosphorus cycle in natural waters are lacking although phosphorus often controls phytoplankton development in aquatic systems. The aim of our study was to analyse effects of elevated CO2 levels on phosphorus pool sizes and uptake. Therefore, we conducted a CO2-manipulation mesocosm experiment in the Storfjärden (western Gulf of Finland, Baltic Sea) in summer 2012. We compared the phosphorus dynamics in different mesocosm treatment
Tim Boxhammer, Lennart T. Bach, Jan Czerny, and Ulf Riebesell
Biogeosciences, 13, 2849–2858, https://doi.org/10.5194/bg-13-2849-2016, https://doi.org/10.5194/bg-13-2849-2016, 2016
Douwe S. Maat, Nicole J. Bale, Ellen C. Hopmans, Jaap S. Sinninghe Damsté, Stefan Schouten, and Corina P. D. Brussaard
Biogeosciences, 13, 1667–1676, https://doi.org/10.5194/bg-13-1667-2016, https://doi.org/10.5194/bg-13-1667-2016, 2016
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This study shows that the phytoplankter Micromonas pusilla alters its lipid composition when the macronutrient phosphate is in low supply. This reduction in phospholipids is directly dependent on the strength of the limitation. Furthermore we show that, when M. pusilla is infected by viruses, lipid remodeling is lower. The study was carried out to investigate how phytoplankton and its viruses are affected by environmental factors and how this affects food web dynamics.
Anna-Karin Almén, Anu Vehmaa, Andreas Brutemark, Lennart Bach, Silke Lischka, Annegret Stuhr, Sara Furuhagen, Allanah Paul, J. Rafael Bermúdez, Ulf Riebesell, and Jonna Engström-Öst
Biogeosciences, 13, 1037–1048, https://doi.org/10.5194/bg-13-1037-2016, https://doi.org/10.5194/bg-13-1037-2016, 2016
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We studied the effects of ocean acidification (OA) on the aquatic crustacean Eurytemora affinis and measured offspring production in relation to pH, chlorophyll, algae, fatty acids, and oxidative stress. No effects on offspring production or pH effects via food were found. E. affinis seems robust against OA on a physiological level and did probably not face acute pH stress in the treatments, as the species naturally face large pH fluctuations.
J. Meyer, C. R. Löscher, S. C. Neulinger, A. F. Reichel, A. Loginova, C. Borchard, R. A. Schmitz, H. Hauss, R. Kiko, and U. Riebesell
Biogeosciences, 13, 781–794, https://doi.org/10.5194/bg-13-781-2016, https://doi.org/10.5194/bg-13-781-2016, 2016
J. Brandsma, T. R. Sutton, J. M. Herniman, J. E. Hunter, T. E. G. Biggs, C. Evans, C. P. D. Brussaard, A. D. Postle, T. J. Jenkins, and G. J. Langley
Biogeosciences Discuss., https://doi.org/10.5194/bg-2016-13, https://doi.org/10.5194/bg-2016-13, 2016
Manuscript not accepted for further review
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Marine phytoplankton fix around 1 billion tonnes of carbon as lipid biomass each year. We present a new method for analysing complex lipid mixtures from phytoplankton biomass using supercritical fluid technology which has better resolution and is several times faster than existing methods. Thus, it enables larger-scale and more in-depth studies of phytoplankton lipid metabolism, the way it is controlled by ecological and environmental processes, and its impact on global biogeochemistry.
M. N. Müller, J. Barcelos e Ramos, K. G. Schulz, U. Riebesell, J. Kaźmierczak, F. Gallo, L. Mackinder, Y. Li, P. N. Nesterenko, T. W. Trull, and G. M. Hallegraeff
Biogeosciences, 12, 6493–6501, https://doi.org/10.5194/bg-12-6493-2015, https://doi.org/10.5194/bg-12-6493-2015, 2015
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The White Cliffs of Dover date back to the Cretaceous and are made up of microscopic chalky shells which were produced mainly by marine phytoplankton (coccolithophores). This is iconic proof for their success at times of relatively high seawater calcium concentrations and, as shown here, to be linked to their ability to precipitate calcium as chalk. The invention of calcification can thus be considered an evolutionary milestone allowing coccolithophores to thrive at times when others struggled.
A. Singh, S. E. Baer, U. Riebesell, A. C. Martiny, and M. W. Lomas
Biogeosciences, 12, 6389–6403, https://doi.org/10.5194/bg-12-6389-2015, https://doi.org/10.5194/bg-12-6389-2015, 2015
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Stoichiometry of macronutrients in the subtropical ocean is important to understand how biogeochemical cycles are coupled. We observed that elemental stoichiometry was much higher in the dissolved organic-matter pools than in the particulate organic matter pools. In addition ratios vary with depth due to changes in growth rates of specific phytoplankton groups, namely cyanobacteria. These data will improve biogeochemical models by placing observational constraints on these ratios.
A. J. Paul, L. T. Bach, K.-G. Schulz, T. Boxhammer, J. Czerny, E. P. Achterberg, D. Hellemann, Y. Trense, M. Nausch, M. Sswat, and U. Riebesell
Biogeosciences, 12, 6181–6203, https://doi.org/10.5194/bg-12-6181-2015, https://doi.org/10.5194/bg-12-6181-2015, 2015
Y. Zhang, N. Mahowald, R. A. Scanza, E. Journet, K. Desboeufs, S. Albani, J. F. Kok, G. Zhuang, Y. Chen, D. D. Cohen, A. Paytan, M. D. Patey, E. P. Achterberg, J. P. Engelbrecht, and K. W. Fomba
Biogeosciences, 12, 5771–5792, https://doi.org/10.5194/bg-12-5771-2015, https://doi.org/10.5194/bg-12-5771-2015, 2015
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A new technique to determine a size-fractionated global soil elemental emission inventory based on a global soil and mineralogical data set is introduced. Spatial variability of mineral dust elemental fractions (8 elements, e.g., Ca, Fe, Al) is identified on a global scale, particularly for Ca. The Ca/Al ratio ranged between 0.1 and 5.0 and is confirmed as an indicator of dust source regions by a global dust model. Total and soluble dust element fluxes into different ocean basins are estimated.
T. Larsen, L. T. Bach, R. Salvatteci, Y. V. Wang, N. Andersen, M. Ventura, and M. D. McCarthy
Biogeosciences, 12, 4979–4992, https://doi.org/10.5194/bg-12-4979-2015, https://doi.org/10.5194/bg-12-4979-2015, 2015
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A tiny fraction of marine algae escapes decomposition and is buried in sediments. Since tools are needed to track the fate of algal organic carbon, we tested whether naturally occurring isotope variability among amino acids from algae and bacteria can be used as source diagnostic fingerprints. We found that isotope fingerprints track algal amino acid sources with high fidelity across different growth conditions, and that the fingerprints can be used to quantify bacterial amino acids in sediment.
L. T. Bach
Biogeosciences, 12, 4939–4951, https://doi.org/10.5194/bg-12-4939-2015, https://doi.org/10.5194/bg-12-4939-2015, 2015
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Calcification by marine organisms reacts to changing seawater carbonate chemistry, but it is unclear which components of the carbonate system drive the observed response. This study uncovers proportionalities between different carbonate chemistry parameters. These enable us to understand why calcification often correlates well with carbonate ion concentration, and they imply that net CaCO3 formation in high latitudes is not more vulnerable to ocean acidification than formation in low latitudes.
M. P. Humphreys, E. P. Achterberg, A. M. Griffiths, A. McDonald, and A. J. Boyce
Earth Syst. Sci. Data, 7, 127–135, https://doi.org/10.5194/essd-7-127-2015, https://doi.org/10.5194/essd-7-127-2015, 2015
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We present measurements of the stable carbon isotope composition of seawater dissolved inorganic carbon. The samples were collected during two research cruises in boreal summer 2012 in the northeastern Atlantic and Nordic Seas. The results can be used to investigate the marine carbon cycle, providing information about biological productivity and oceanic uptake of anthropogenic carbon dioxide.
J. Meyer and U. Riebesell
Biogeosciences, 12, 1671–1682, https://doi.org/10.5194/bg-12-1671-2015, https://doi.org/10.5194/bg-12-1671-2015, 2015
K. Spilling, A. Kremp, R. Klais, K. Olli, and T. Tamminen
Biogeosciences, 11, 7275–7289, https://doi.org/10.5194/bg-11-7275-2014, https://doi.org/10.5194/bg-11-7275-2014, 2014
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Recent evidence suggests that competition between phytoplankton groups is significantly affected by changing climatic factors. We investigated the effects of phytoplankton community composition on spring bloom carbon flows. The comparison of differing communities showed that community structure significantly affected C accumulation parameters. Climate-driven changes in phytoplankton dominance patterns will have far-reaching consequences for major biogeochemical cycles.
S. A. Krueger-Hadfield, C. Balestreri, J. Schroeder, A. Highfield, P. Helaouët, J. Allum, R. Moate, K. T. Lohbeck, P. I. Miller, U. Riebesell, T. B. H. Reusch, R. E. M. Rickaby, J. Young, G. Hallegraeff, C. Brownlee, and D. C. Schroeder
Biogeosciences, 11, 5215–5234, https://doi.org/10.5194/bg-11-5215-2014, https://doi.org/10.5194/bg-11-5215-2014, 2014
K. Attermeyer, T. Hornick, Z. E. Kayler, A. Bahr, E. Zwirnmann, H.-P. Grossart, and K. Premke
Biogeosciences, 11, 1479–1489, https://doi.org/10.5194/bg-11-1479-2014, https://doi.org/10.5194/bg-11-1479-2014, 2014
M. N. Müller, M. Lebrato, U. Riebesell, J. Barcelos e Ramos, K. G. Schulz, S. Blanco-Ameijeiras, S. Sett, A. Eisenhauer, and H. M. Stoll
Biogeosciences, 11, 1065–1075, https://doi.org/10.5194/bg-11-1065-2014, https://doi.org/10.5194/bg-11-1065-2014, 2014
D. S. Maat, N. J. Bale, E. C. Hopmans, A.-C. Baudoux, J. S. Sinninghe Damsté, S. Schouten, and C. P. D. Brussaard
Biogeosciences, 11, 185–194, https://doi.org/10.5194/bg-11-185-2014, https://doi.org/10.5194/bg-11-185-2014, 2014
A. Silyakova, R. G. J. Bellerby, K. G. Schulz, J. Czerny, T. Tanaka, G. Nondal, U. Riebesell, A. Engel, T. De Lange, and A. Ludvig
Biogeosciences, 10, 4847–4859, https://doi.org/10.5194/bg-10-4847-2013, https://doi.org/10.5194/bg-10-4847-2013, 2013
W. H. van de Poll, G. Kulk, K. R. Timmermans, C. P. D. Brussaard, H. J. van der Woerd, M. J. Kehoe, K. D. A. Mojica, R. J. W. Visser, P. D. Rozema, and A. G. J. Buma
Biogeosciences, 10, 4227–4240, https://doi.org/10.5194/bg-10-4227-2013, https://doi.org/10.5194/bg-10-4227-2013, 2013
C. Motegi, T. Tanaka, J. Piontek, C. P. D. Brussaard, J.-P. Gattuso, and M. G. Weinbauer
Biogeosciences, 10, 3285–3296, https://doi.org/10.5194/bg-10-3285-2013, https://doi.org/10.5194/bg-10-3285-2013, 2013
J. Czerny, K. G. Schulz, T. Boxhammer, R. G. J. Bellerby, J. Büdenbender, A. Engel, S. A. Krug, A. Ludwig, K. Nachtigall, G. Nondal, B. Niehoff, A. Silyakova, and U. Riebesell
Biogeosciences, 10, 3109–3125, https://doi.org/10.5194/bg-10-3109-2013, https://doi.org/10.5194/bg-10-3109-2013, 2013
F. E. Hopkins, S. A. Kimmance, J. A. Stephens, R. G. J. Bellerby, C. P. D. Brussaard, J. Czerny, K. G. Schulz, and S. D. Archer
Biogeosciences, 10, 2331–2345, https://doi.org/10.5194/bg-10-2331-2013, https://doi.org/10.5194/bg-10-2331-2013, 2013
J. Czerny, K. G. Schulz, S. A. Krug, A. Ludwig, and U. Riebesell
Biogeosciences, 10, 1937–1941, https://doi.org/10.5194/bg-10-1937-2013, https://doi.org/10.5194/bg-10-1937-2013, 2013
U. Riebesell, J. Czerny, K. von Bröckel, T. Boxhammer, J. Büdenbender, M. Deckelnick, M. Fischer, D. Hoffmann, S. A. Krug, U. Lentz, A. Ludwig, R. Muche, and K. G. Schulz
Biogeosciences, 10, 1835–1847, https://doi.org/10.5194/bg-10-1835-2013, https://doi.org/10.5194/bg-10-1835-2013, 2013
N. Aberle, K. G. Schulz, A. Stuhr, A. M. Malzahn, A. Ludwig, and U. Riebesell
Biogeosciences, 10, 1471–1481, https://doi.org/10.5194/bg-10-1471-2013, https://doi.org/10.5194/bg-10-1471-2013, 2013
A. de Kluijver, K. Soetaert, J. Czerny, K. G. Schulz, T. Boxhammer, U. Riebesell, and J. J. Middelburg
Biogeosciences, 10, 1425–1440, https://doi.org/10.5194/bg-10-1425-2013, https://doi.org/10.5194/bg-10-1425-2013, 2013
A. Engel, C. Borchard, J. Piontek, K. G. Schulz, U. Riebesell, and R. Bellerby
Biogeosciences, 10, 1291–1308, https://doi.org/10.5194/bg-10-1291-2013, https://doi.org/10.5194/bg-10-1291-2013, 2013
C. P. D. Brussaard, A. A. M. Noordeloos, H. Witte, M. C. J. Collenteur, K. Schulz, A. Ludwig, and U. Riebesell
Biogeosciences, 10, 719–731, https://doi.org/10.5194/bg-10-719-2013, https://doi.org/10.5194/bg-10-719-2013, 2013
A.-S. Roy, S. M. Gibbons, H. Schunck, S. Owens, J. G. Caporaso, M. Sperling, J. I. Nissimov, S. Romac, L. Bittner, M. Mühling, U. Riebesell, J. LaRoche, and J. A. Gilbert
Biogeosciences, 10, 555–566, https://doi.org/10.5194/bg-10-555-2013, https://doi.org/10.5194/bg-10-555-2013, 2013
T. Tanaka, S. Alliouane, R. G. B. Bellerby, J. Czerny, A. de Kluijver, U. Riebesell, K. G. Schulz, A. Silyakova, and J.-P. Gattuso
Biogeosciences, 10, 315–325, https://doi.org/10.5194/bg-10-315-2013, https://doi.org/10.5194/bg-10-315-2013, 2013
J. Piontek, C. Borchard, M. Sperling, K. G. Schulz, U. Riebesell, and A. Engel
Biogeosciences, 10, 297–314, https://doi.org/10.5194/bg-10-297-2013, https://doi.org/10.5194/bg-10-297-2013, 2013
M. Sperling, J. Piontek, G. Gerdts, A. Wichels, H. Schunck, A.-S. Roy, J. La Roche, J. Gilbert, J. I. Nissimov, L. Bittner, S. Romac, U. Riebesell, and A. Engel
Biogeosciences, 10, 181–191, https://doi.org/10.5194/bg-10-181-2013, https://doi.org/10.5194/bg-10-181-2013, 2013
K. G. Schulz, R. G. J. Bellerby, C. P. D. Brussaard, J. Büdenbender, J. Czerny, A. Engel, M. Fischer, S. Koch-Klavsen, S. A. Krug, S. Lischka, A. Ludwig, M. Meyerhöfer, G. Nondal, A. Silyakova, A. Stuhr, and U. Riebesell
Biogeosciences, 10, 161–180, https://doi.org/10.5194/bg-10-161-2013, https://doi.org/10.5194/bg-10-161-2013, 2013
Related subject area
Biogeochemistry: Environmental Microbiology
Technical note: Flow cytometry assays for the detection, counting and cell sorting of polyphosphate-accumulating bacteria
Animal burrowing at cold seep ecotones boosts productivity by linking macromolecule turnover with chemosynthesis and nutrient cycling
Clouds influence the functioning of airborne microorganisms
Grazing mortality as a controlling factor in the uncultured non-cyanobacterial diazotroph (Gamma A) around the Kuroshio region
Ideas and perspectives: Microorganisms in the air through the lenses of atmospheric chemistry and microphysics
Effects of surface water interactions with karst groundwater on microbial biomass, metabolism, and production
Overview: Global change effects on terrestrial biogeochemistry at the plant–soil interface
Changes in diazotrophic community structure associated with Kuroshio succession in the northern South China Sea
Technical note: A comparison of methods for estimating coccolith mass
Fractionation of stable carbon isotopes during formate consumption in anoxic rice paddy soils and lake sediments
Characteristics of bacterial and fungal communities and their associations with sugar compounds in atmospheric aerosols at a rural site in northern China
Responses of globally important phytoplankton species to olivine dissolution products and implications for carbon dioxide removal via ocean alkalinity enhancement
Differentiation of cognate bacterial communities in thermokarst landscapes: implications for ecological consequences of permafrost degradation
A multi-phase biogeochemical model for mitigating earthquake-induced liquefaction via microbially induced desaturation and calcium carbonate precipitation
Phosphorus regulates ectomycorrhizal fungi biomass production in a Norway spruce forest
Reallocation of elemental content and macromolecules in the coccolithophore Emiliania huxleyi to acclimate to climate change
Abrasion of sedimentary rocks as a source of hydrogen peroxide and nutrients to subglacial ecosystems
Nitrous oxide (N2O) synthesis by the freshwater cyanobacterium Microcystis aeruginosa
Interdisciplinary strategy to assess the impact of meteorological variables on the biochemical composition of the rain and the dynamics of a small eutrophic lake under rain forcing
Depth-related patterns in microbial community responses to complex organic matter in the western North Atlantic Ocean
Assessing the influence of ocean alkalinity enhancement on a coastal phytoplankton community
Eddy-enhanced primary production sustains heterotrophic microbial activities in the Eastern Tropical North Atlantic
Composition and niche-specific characteristics of microbial consortia colonizing Marsberg copper mine in the Rhenish Massif
Diversity and assembly processes of microbial eukaryotic communities in Fildes Peninsula Lakes (West Antarctica)
Nitrophobic ectomycorrhizal fungi are associated with enhanced hydrophobicity of soil organic matter in a Norway spruce forest
Physiological control on carbon isotope fractionation in marine phytoplankton
Implementation of mycorrhizal mechanisms into soil carbon model improves the prediction of long-term processes of plant litter decomposition
Impact of dust addition on the microbial food web under present and future conditions of pH and temperature
Fractionation of stable carbon isotopes during acetate consumption by methanogenic and sulfidogenic microbial communities in rice paddy soils and lake sediments
Hydrothermal trace metal release and microbial metabolism in the northeastern Lau Basin of the South Pacific Ocean
Sedimentation rate and organic matter dynamics shape microbiomes across a continental margin
Disturbance triggers non-linear microbe–environment feedbacks
Hydrographic fronts shape productivity, nitrogen fixation, and microbial community composition in the southern Indian Ocean and the Southern Ocean
Microbial and geo-archaeological records reveal the growth rate, origin and composition of desert rock surface communities
Metagenomic insights into the metabolism of microbial communities that mediate iron and methane cycling in Lake Kinneret iron-rich methanic sediments
Spatiotemporal patterns of N2 fixation in coastal waters derived from rate measurements and remote sensing
Biotic and abiotic transformation of amino acids in cloud water: experimental studies and atmospheric implications
Potential bioavailability of organic matter from atmospheric particles to marine heterotrophic bacteria
Microbial functional signature in the atmospheric boundary layer
New insight to niche partitioning and ecological function of ammonia oxidizing archaea in subtropical estuarine ecosystem
Impact of reactive surfaces on the abiotic reaction between nitrite and ferrous iron and associated nitrogen and oxygen isotope dynamics
Reviews and syntheses: Bacterial bioluminescence – ecology and impact in the biological carbon pump
Salinity-dependent algae uptake and subsequent carbon and nitrogen metabolisms of two intertidal foraminifera (Ammonia tepida and Haynesina germanica)
On giant shoulders: how a seamount affects the microbial community composition of seawater and sponges
Spatial variations in sedimentary N-transformation rates in the North Sea (German Bight)
Patterns of (trace) metals and microorganisms in the Rainbow hydrothermal vent plume at the Mid-Atlantic Ridge
Co-occurrence of Fe and P stress in natural populations of the marine diazotroph Trichodesmium
Senescence as the main driver of iodide release from a diverse range of marine phytoplankton
Reviews and syntheses: Biological weathering and its consequences at different spatial levels – from nanoscale to global scale
Deep-sea sponge grounds as nutrient sinks: denitrification is common in boreo-Arctic sponges
Clémentin Bouquet, Hermine Billard, Cécile C. Bidaud, Jonathan Colombet, Young-Tae Chang, Joan Artigas, Isabelle Batisson, Karim Benzerara, Fériel Skouri-Panet, Elodie Duprat, and Anne-Catherine Lehours
Biogeosciences, 22, 1729–1744, https://doi.org/10.5194/bg-22-1729-2025, https://doi.org/10.5194/bg-22-1729-2025, 2025
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In the context of the ecological sustainability of phosphorus, the ubiquitous presence of polyphosphate-accumulating bacteria in natural environments invites efforts to reveal their unknown roles in the biogeochemical cycle of phosphorus. In this study, we evaluated the potential of combining the staining of intracellular polyphosphate granules and their subsequent detection by flow cytometry for the detection, quantification and cell sorting of polyphosphate-accumulating bacteria.
Maxim Rubin-Blum, Eyal Rahav, Guy Sisma-Ventura, Yana Yudkovski, Zoya Harbuzov, Or M. Bialik, Oded Ezra, Anneleen Foubert, Barak Herut, and Yizhaq Makovsky
Biogeosciences, 22, 1321–1340, https://doi.org/10.5194/bg-22-1321-2025, https://doi.org/10.5194/bg-22-1321-2025, 2025
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Chemotones, transition zones in chemosynthetic ecosystems, alter geochemical cycles and biodiversity. We studied seep chemotones, which are heavily burrowed by ghost shrimp. To investigate if burrowing affects habitat functionality, we surveyed the seafloor with deep-sea vehicles, analyzed sediment, and explored microbial communities in burrows. We found chemosynthetic biofilms, linking them to macromolecule turnover and nutrient cycling. This process may play a crucial role in deep-sea cycles.
Raphaëlle Péguilhan, Florent Rossi, Muriel Joly, Engy Nasr, Bérénice Batut, François Enault, Barbara Ervens, and Pierre Amato
Biogeosciences, 22, 1257–1275, https://doi.org/10.5194/bg-22-1257-2025, https://doi.org/10.5194/bg-22-1257-2025, 2025
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Using comparative metagenomics and metatranscriptomics, we examined the functioning of airborne microorganisms in clouds and a clear atmosphere. Clouds are atmospheric masses where multiple microbial processes are promoted compared with a clear atmosphere. Overrepresented microbial functions of interest include the processing of chemical compounds, biomass production, and regulation of oxidants. This has implications for biogeochemical cycles and microbial ecology.
Takuya Sato, Tamaha Yamaguchi, Kiyotaka Hidaka, Sayaka Sogawa, Takashi Setou, Taketoshi Kodama, Takuhei Shiozaki, and Kazutaka Takahashi
Biogeosciences, 22, 625–639, https://doi.org/10.5194/bg-22-625-2025, https://doi.org/10.5194/bg-22-625-2025, 2025
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Gamma A is a widespread non-cyanobacterial diazotroph that plays a crucial role in marine ecosystems, but its controlling factors are still largely unknown. This study, for the first time, quantified microzooplankton grazing on Gamma A and revealed the significance of grazing pressure on Gamma A distribution around the Kuroshio region. It highlights the importance of top-down controls on Gamma A abundance and the associated nitrogen cycle.
Barbara Ervens, Pierre Amato, Kifle Aregahegn, Muriel Joly, Amina Khaled, Tiphaine Labed-Veydert, Frédéric Mathonat, Leslie Nuñez López, Raphaëlle Péguilhan, and Minghui Zhang
Biogeosciences, 22, 243–256, https://doi.org/10.5194/bg-22-243-2025, https://doi.org/10.5194/bg-22-243-2025, 2025
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Atmospheric microorganisms are a small fraction of Earth's microbiome, with bacteria being a significant part. Aerosolized bacteria are airborne for a few days, encountering unique chemical and physical conditions affecting stress levels and survival. We explore chemical and microphysical conditions bacteria encounter, highlighting potential nutrient and oxidant limitations and diverse effects by pollutants, which may ultimately impact the microbiome's role in global ecosystems and biodiversity.
Adrian Barry-Sosa, Madison K. Flint, Justin C. Ellena, Jonathan B. Martin, and Brent C. Christner
Biogeosciences, 21, 3965–3984, https://doi.org/10.5194/bg-21-3965-2024, https://doi.org/10.5194/bg-21-3965-2024, 2024
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This study examined springs in north central Florida focusing on how interactions between the surface and subsurface affected the properties of groundwater microbes. We found that microbes reproduced at rates that greatly exceed those documented for any other aquifer. Although the groundwater discharged to spring runs contains low concentrations of nutrients, our results indicate that microbes have access to sources of energy and produce new cells at rates similar to surface waterbodies.
Lucia Fuchslueger, Emily Francesca Solly, Alberto Canarini, and Albert Carles Brangarí
Biogeosciences, 21, 3959–3964, https://doi.org/10.5194/bg-21-3959-2024, https://doi.org/10.5194/bg-21-3959-2024, 2024
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This overview of the special issue “Global change effects on terrestrial biogeochemistry at the plant–soil interface” features empirical, conceptual and modelling-based studies and outlines key findings on plant responses to elevated CO2; soil organism responses to warming; impacts on soil organic carbon, nitrogen and mineral nutrient cycling; and water level changes affecting greenhouse gas emissions, from the Arctic to the tropics, which are crucial for deciphering feedbacks to global change.
Han Zhang, Guangming Mai, Weicheng Luo, Meng Chen, Ran Duan, and Tuo Shi
Biogeosciences, 21, 2529–2546, https://doi.org/10.5194/bg-21-2529-2024, https://doi.org/10.5194/bg-21-2529-2024, 2024
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We report taxon-specific biogeography of N2-fixing microbes (diazotrophs) driven by Kuroshio intrusion (Kl) into the South China Sea. We show that the composition and distribution of distinct diazotrophic taxa shift with Kl-induced variations in physicochemical parameters of seawater and that Kl shapes diazotrophic community primarily as a stochastic process. This study thus has implications for the distribution of diazotrophs in a future warming ocean, as Kls are projected to intensify.
Celina Rebeca Valença, Luc Beaufort, Gustaaf Marinus Hallegraeff, and Marius Nils Müller
Biogeosciences, 21, 1601–1611, https://doi.org/10.5194/bg-21-1601-2024, https://doi.org/10.5194/bg-21-1601-2024, 2024
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Coccolithophores contribute to the global carbon cycle and their calcite structures (coccoliths) are used as a palaeoproxy to understand past oceanographic conditions. Here, we compared three frequently used methods to estimate coccolith mass from the model species Emiliania huxleyi and the results allow for a high level of comparability between the methods, facilitating future comparisons and consolidation of mass changes observed from ecophysiological and biogeochemical studies.
Ralf Conrad and Peter Claus
Biogeosciences, 21, 1161–1172, https://doi.org/10.5194/bg-21-1161-2024, https://doi.org/10.5194/bg-21-1161-2024, 2024
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Knowledge of carbon isotope fractionation is important for the assessment of the pathways involved in the degradation of organic matter. Formate is an important intermediate during this process. It was mainly converted to carbon dioxide and acetate both in the presence and absence of sulfate. Methane was only a minor product and was mainly formed from the acetate. The acetate was depleted in the heavy carbon atom relative to formate, while the carbon dioxide was enriched.
Mutong Niu, Shu Huang, Wei Hu, Yajie Wang, Wanyun Xu, Wan Wei, Qiang Zhang, Zihan Wang, Donghuan Zhang, Rui Jin, Libin Wu, Junjun Deng, Fangxia Shen, and Pingqing Fu
Biogeosciences, 20, 4915–4930, https://doi.org/10.5194/bg-20-4915-2023, https://doi.org/10.5194/bg-20-4915-2023, 2023
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Sugar compounds in air can trace the source of bioaerosols that affect public health and climate. In rural north China, we observed increased fungal activity at night and less variable bacterial community diversity. Certain night-increasing sugar compounds were more closely related to fungi than bacteria. The fungal community greatly influenced sugar compounds, while bacteria played a limited role. Caution is advised when using sugar compounds to trace airborne microbes, particularly bacteria.
David A. Hutchins, Fei-Xue Fu, Shun-Chung Yang, Seth G. John, Stephen J. Romaniello, M. Grace Andrews, and Nathan G. Walworth
Biogeosciences, 20, 4669–4682, https://doi.org/10.5194/bg-20-4669-2023, https://doi.org/10.5194/bg-20-4669-2023, 2023
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Applications of the mineral olivine are a promising means to capture carbon dioxide via coastal enhanced weathering, but little is known about the impacts on important marine phytoplankton. We examined the effects of olivine dissolution products on species from three major phytoplankton groups: diatoms, coccolithophores, and cyanobacteria. Growth and productivity were generally either unaffected or stimulated, suggesting the effects of olivine on key phytoplankton are negligible or positive.
Ze Ren, Shudan Ye, Hongxuan Li, Xilei Huang, and Luyao Chen
Biogeosciences, 20, 4241–4258, https://doi.org/10.5194/bg-20-4241-2023, https://doi.org/10.5194/bg-20-4241-2023, 2023
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Permafrost thaw initiates thermokarst landscape formation, resulting in distinct new habitats, including degraded permafrost soil, thermokarst lake sediments, and lake water. These distinct habitats harbored differentiated bacterial communities that originated from the same source, differing in diversity, assembly mechanisms, and environmental influences. The results imply ecological consequences of permafrost degradation in the face of further climate change.
Caitlyn A. Hall, Andre van Turnhout, Edward Kavazanjian Jr., Leon A. van Paassen, and Bruce Rittmann
Biogeosciences, 20, 2903–2917, https://doi.org/10.5194/bg-20-2903-2023, https://doi.org/10.5194/bg-20-2903-2023, 2023
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Earthquake-induced soil liquefaction poses a significant global threat. Microbially induced desaturation and precipitation (MIDP) via denitrification is a potentially sustainable, non-disruptive bacteria-driven ground improvement technique under existing structures. We developed a next-generation biogeochemical model to understand and predict the behavior of MIDP in the natural environment to design field-based hazard mitigation treatments.
Juan Pablo Almeida, Lorenzo Menichetti, Alf Ekblad, Nicholas P. Rosenstock, and Håkan Wallander
Biogeosciences, 20, 1443–1458, https://doi.org/10.5194/bg-20-1443-2023, https://doi.org/10.5194/bg-20-1443-2023, 2023
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In forests, trees allocate a significant amount of carbon belowground to support mycorrhizal symbiosis. In northern forests nitrogen normally regulates this allocation and consequently mycorrhizal fungi growth. In this study we demonstrate that in a conifer forest from Sweden, fungal growth is regulated by phosphorus instead of nitrogen. This is probably due to an increase in nitrogen deposition to soils caused by decades of human pollution that has altered the ecosystem nutrient regime.
Yong Zhang, Yong Zhang, Shuai Ma, Hanbing Chen, Jiabing Li, Zhengke Li, Kui Xu, Ruiping Huang, Hong Zhang, Yonghe Han, and Jun Sun
Biogeosciences, 20, 1299–1312, https://doi.org/10.5194/bg-20-1299-2023, https://doi.org/10.5194/bg-20-1299-2023, 2023
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We found that increasing light intensity compensates for the negative effects of low phosphorus (P) availability on cellular protein and nitrogen contents. Reduced P availability, increasing light intensity, and ocean acidification act synergistically to increase cellular contents of carbohydrate and POC and the allocation of POC to carbohydrate. These regulation mechanisms in Emiliania huxleyi could provide vital information for evaluating carbon cycle in marine ecosystems under global change.
Beatriz Gill-Olivas, Jon Telling, Mark Skidmore, and Martyn Tranter
Biogeosciences, 20, 929–943, https://doi.org/10.5194/bg-20-929-2023, https://doi.org/10.5194/bg-20-929-2023, 2023
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Microbial ecosystems have been found in all subglacial environments sampled to date. Yet, little is known of the sources of energy and nutrients that sustain these microbial populations. This study shows that crushing of sedimentary rocks, which contain organic carbon, carbonate and sulfide minerals, along with previously weathered silicate minerals, produces a range of compounds and nutrients which can be utilised by the diverse suite of microbes that inhabit glacier beds.
Federico Fabisik, Benoit Guieysse, Jonathan Procter, and Maxence Plouviez
Biogeosciences, 20, 687–693, https://doi.org/10.5194/bg-20-687-2023, https://doi.org/10.5194/bg-20-687-2023, 2023
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We show, for the first time, that pure cultures of the cyanobacterium Microcystis aeruginosa can synthesize the potent greenhouse gas N2O using nitrite as substrate. Our findings have broad environmental implications because M. aeruginosa is globally found in freshwater ecosystems and is often the dominant species found in algae blooms. Further research is now needed to determine the occurrence and significance of N2O emissions from ecosystems rich with M. aeruginosa.
Fanny Noirmain, Jean-Luc Baray, Frédéric Tridon, Philippe Cacault, Hermine Billard, Guillaume Voyard, Joël Van Baelen, and Delphine Latour
Biogeosciences, 19, 5729–5749, https://doi.org/10.5194/bg-19-5729-2022, https://doi.org/10.5194/bg-19-5729-2022, 2022
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We present a study linking rain, meteorology, and mountain lake phytoplankton dynamics on the basis of a case study at Aydat (France) in September 2020. The air mass origin mainly influences the rain chemical composition, which depends on the type of rain, convective or stratiform. Our results also highlighted a non-negligible presence of photosynthetic cells in rainwater. The impact of the atmospheric forcing on the lake could play a key role in phytoplankton dynamics in the temperate zone.
Sarah A. Brown, John Paul Balmonte, Adrienne Hoarfrost, Sherif Ghobrial, and Carol Arnosti
Biogeosciences, 19, 5617–5631, https://doi.org/10.5194/bg-19-5617-2022, https://doi.org/10.5194/bg-19-5617-2022, 2022
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Bacteria use extracellular enzymes to cut large organic matter to sizes small enough for uptake. We compared the enzymatic response of surface, mid-water, and deep-ocean bacteria to complex natural substrates. Bacteria in surface and mid-depth waters produced a much wider range of enzymes than those in the deep ocean and may therefore consume a broader range of organic matter. The extent to which organic matter is recycled by bacteria depends in part on its residence time at different depths.
Aaron Ferderer, Zanna Chase, Fraser Kennedy, Kai G. Schulz, and Lennart T. Bach
Biogeosciences, 19, 5375–5399, https://doi.org/10.5194/bg-19-5375-2022, https://doi.org/10.5194/bg-19-5375-2022, 2022
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Ocean alkalinity enhancement has the capacity to remove vast quantities of carbon from the atmosphere, but its effect on marine ecosystems is largely unknown. We assessed the effect of increased alkalinity on a coastal phytoplankton community when seawater was equilibrated and not equilibrated with atmospheric CO2. We found that the phytoplankton community was moderately affected by increased alkalinity and equilibration with atmospheric CO2 had little influence on this effect.
Quentin Devresse, Kevin W. Becker, Arne Bendinger, Johannes Hahn, and Anja Engel
Biogeosciences, 19, 5199–5219, https://doi.org/10.5194/bg-19-5199-2022, https://doi.org/10.5194/bg-19-5199-2022, 2022
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Eddies are ubiquitous in the ocean and alter physical, chemical, and biological processes. However, how they affect organic carbon production and consumption is largely unknown. Here we show how an eddy triggers a cascade effect on biomass production and metabolic activities of phyto- and bacterioplankton. Our results may contribute to the improvement of biogeochemical models used to estimate carbon fluxes in the ocean.
Sania Arif, Heiko Nacke, Elias Schliekmann, Andreas Reimer, Gernot Arp, and Michael Hoppert
Biogeosciences, 19, 4883–4902, https://doi.org/10.5194/bg-19-4883-2022, https://doi.org/10.5194/bg-19-4883-2022, 2022
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The natural enrichment of Chloroflexi (Ktedonobacteria) at the Kilianstollen Marsberg copper mine rocks being exposed to the acidic sulfate-rich leachate led to an investigation of eight metagenomically assembled genomes (MAGs) involved in copper and other transition heavy metal resistance in addition to low pH resistance and aromatic compounds degradation. The present study offers functional insights about a novel cold-adapted Ktedonobacteria MAG extremophily along with other phyla MAGs.
Chunmei Zhang, Huirong Li, Yinxin Zeng, Haitao Ding, Bin Wang, Yangjie Li, Zhongqiang Ji, Yonghong Bi, and Wei Luo
Biogeosciences, 19, 4639–4654, https://doi.org/10.5194/bg-19-4639-2022, https://doi.org/10.5194/bg-19-4639-2022, 2022
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The unique microbial eukaryotic community structure and lower diversity have been demonstrated in five freshwater lakes of the Fildes Peninsula, Antarctica. Stochastic processes and biotic co-occurrence patterns were shown to be important in shaping microbial eukaryotic communities in the area. Our study provides a better understanding of the dynamic patterns and ecological assembly processes of microbial eukaryotic communities in Antarctic oligotrophic lakes (Fildes Peninsula).
Juan Pablo Almeida, Nicholas P. Rosenstock, Susanne K. Woche, Georg Guggenberger, and Håkan Wallander
Biogeosciences, 19, 3713–3726, https://doi.org/10.5194/bg-19-3713-2022, https://doi.org/10.5194/bg-19-3713-2022, 2022
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Fungi living in symbiosis with tree roots can accumulate belowground, forming special tissues than can repel water. We measured the water repellency of organic material incubated belowground and correlated it with fungal growth. We found a positive association between water repellency and root symbiotic fungi. These results are important because an increase in soil water repellency can reduce the release of CO2 from soils into the atmosphere and mitigate the effects of greenhouse gasses.
Karen M. Brandenburg, Björn Rost, Dedmer B. Van de Waal, Mirja Hoins, and Appy Sluijs
Biogeosciences, 19, 3305–3315, https://doi.org/10.5194/bg-19-3305-2022, https://doi.org/10.5194/bg-19-3305-2022, 2022
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Reconstructions of past CO2 concentrations rely on proxy estimates, with one line of proxies relying on the CO2-dependence of stable carbon isotope fractionation in marine phytoplankton. Culturing experiments provide insights into which processes may impact this. We found, however, that the methods with which these culturing experiments are performed also influence 13C fractionation. Caution should therefore be taken when extrapolating results from these experiments to proxy applications.
Weilin Huang, Peter M. van Bodegom, Toni Viskari, Jari Liski, and Nadejda A. Soudzilovskaia
Biogeosciences, 19, 1469–1490, https://doi.org/10.5194/bg-19-1469-2022, https://doi.org/10.5194/bg-19-1469-2022, 2022
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This work focuses on one of the essential pathways of mycorrhizal impact on C cycles: the mediation of plant litter decomposition. We present a model based on litter chemical quality which precludes a conclusive examination of mycorrhizal impacts on soil C. It improves long-term decomposition predictions and advances our understanding of litter decomposition dynamics. It creates a benchmark in quantitatively examining the impacts of plant–microbe interactions on soil C dynamics.
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
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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.
Ralf Conrad, Pengfei Liu, and Peter Claus
Biogeosciences, 18, 6533–6546, https://doi.org/10.5194/bg-18-6533-2021, https://doi.org/10.5194/bg-18-6533-2021, 2021
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Acetate is an important intermediate during the anaerobic degradation of organic matter. It is consumed by methanogenic and sulfidogenic microorganisms accompanied by stable carbon isotope fractionation. We determined isotope fractionation under different conditions in two paddy soils and two lake sediments and also determined the composition of the microbial communities. Despite a relatively wide range of experimental conditions, the range of fractionation factors was quite moderate.
Natalie R. Cohen, Abigail E. Noble, Dawn M. Moran, Matthew R. McIlvin, Tyler J. Goepfert, Nicholas J. Hawco, Christopher R. German, Tristan J. Horner, Carl H. Lamborg, John P. McCrow, Andrew E. Allen, and Mak A. Saito
Biogeosciences, 18, 5397–5422, https://doi.org/10.5194/bg-18-5397-2021, https://doi.org/10.5194/bg-18-5397-2021, 2021
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A previous study documented an intense hydrothermal plume in the South Pacific Ocean; however, the iron release associated with this plume and the impact on microbiology were unclear. We describe metal concentrations associated with multiple hydrothermal plumes in this region and protein signatures of plume-influenced microbes. Our findings demonstrate that resources released from these systems can be transported away from their source and may alter the physiology of surrounding microbes.
Sabyasachi Bhattacharya, Tarunendu Mapder, Svetlana Fernandes, Chayan Roy, Jagannath Sarkar, Moidu Jameela Rameez, Subhrangshu Mandal, Abhijit Sar, Amit Kumar Chakraborty, Nibendu Mondal, Sumit Chatterjee, Bomba Dam, Aditya Peketi, Ranadhir Chakraborty, Aninda Mazumdar, and Wriddhiman Ghosh
Biogeosciences, 18, 5203–5222, https://doi.org/10.5194/bg-18-5203-2021, https://doi.org/10.5194/bg-18-5203-2021, 2021
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Physicochemical determinants of microbiome architecture across continental shelves–slopes are unknown, so we explored the geomicrobiology along 3 m sediment horizons of seasonal (shallow coastal) and perennial (deep sea) hypoxic zones of the Arabian Sea. Nature, concentration, and fate of the organic matter delivered to the sea floor were found to shape the microbiome across the western Indian margin, under direct–indirect influence of sedimentation rate and water column O2 level.
Aditi Sengupta, Sarah J. Fansler, Rosalie K. Chu, Robert E. Danczak, Vanessa A. Garayburu-Caruso, Lupita Renteria, Hyun-Seob Song, Jason Toyoda, Jacqueline Hager, and James C. Stegen
Biogeosciences, 18, 4773–4789, https://doi.org/10.5194/bg-18-4773-2021, https://doi.org/10.5194/bg-18-4773-2021, 2021
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Conceptual models link microbes with the environment but are untested. We test a recent model using riverbed sediments. We exposed sediments to disturbances, going dry and becoming wet again. As the length of dry conditions got longer, there was a sudden shift in the ecology of microbes, chemistry of organic matter, and rates of microbial metabolism. We propose a new model based on feedbacks initiated by disturbance that cascade across biological, chemical, and functional aspects of the system.
Cora Hörstmann, Eric J. Raes, Pier Luigi Buttigieg, Claire Lo Monaco, Uwe John, and Anya M. Waite
Biogeosciences, 18, 3733–3749, https://doi.org/10.5194/bg-18-3733-2021, https://doi.org/10.5194/bg-18-3733-2021, 2021
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Microbes are the main drivers of productivity and nutrient cycling in the ocean. We present a combined approach assessing C and N uptake and microbial community diversity across ecological provinces in the Southern Ocean and southern Indian Ocean. Provinces showed distinct genetic fingerprints, but microbial activity varied gradually across regions, correlating with nutrient concentrations. Our study advances the biogeographic understanding of microbial diversity across C and N uptake regimes.
Nimrod Wieler, Tali Erickson Gini, Osnat Gillor, and Roey Angel
Biogeosciences, 18, 3331–3342, https://doi.org/10.5194/bg-18-3331-2021, https://doi.org/10.5194/bg-18-3331-2021, 2021
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Biological rock crusts (BRCs) are common microbial-based assemblages covering rocks in drylands. BRCs play a crucial role in arid environments because of the limited activity of plants and soil. Nevertheless, BRC development rates have never been dated. Here we integrated archaeological, microbiological and geological methods to provide a first estimation of the growth rate of BRCs under natural conditions. This can serve as an affordable dating tool in archaeological sites in arid regions.
Michal Elul, Maxim Rubin-Blum, Zeev Ronen, Itay Bar-Or, Werner Eckert, and Orit Sivan
Biogeosciences, 18, 2091–2106, https://doi.org/10.5194/bg-18-2091-2021, https://doi.org/10.5194/bg-18-2091-2021, 2021
Mindaugas Zilius, Irma Vybernaite-Lubiene, Diana Vaiciute, Donata Overlingė, Evelina Grinienė, Anastasija Zaiko, Stefano Bonaglia, Iris Liskow, Maren Voss, Agneta Andersson, Sonia Brugel, Tobia Politi, and Paul A. Bukaveckas
Biogeosciences, 18, 1857–1871, https://doi.org/10.5194/bg-18-1857-2021, https://doi.org/10.5194/bg-18-1857-2021, 2021
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In fresh and brackish waters, algal blooms are often dominated by cyanobacteria, which have the ability to utilize atmospheric nitrogen. Cyanobacteria are also unusual in that they float to the surface and are dispersed by wind-driven currents. Their patchy and dynamic distribution makes it difficult to track their abundance and quantify their effects on nutrient cycling. We used remote sensing to map the distribution of cyanobacteria in a large Baltic lagoon and quantify their contributions.
Saly Jaber, Muriel Joly, Maxence Brissy, Martin Leremboure, Amina Khaled, Barbara Ervens, and Anne-Marie Delort
Biogeosciences, 18, 1067–1080, https://doi.org/10.5194/bg-18-1067-2021, https://doi.org/10.5194/bg-18-1067-2021, 2021
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Our study is of interest to atmospheric scientists and environmental microbiologists, as we show that clouds can be considered a medium where bacteria efficiently degrade and transform amino acids, in competition with chemical processes. As current atmospheric multiphase models are restricted to chemical degradation of organic compounds, our conclusions motivate further model development.
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
Romie Tignat-Perrier, Aurélien Dommergue, Alban Thollot, Olivier Magand, Timothy M. Vogel, and Catherine Larose
Biogeosciences, 17, 6081–6095, https://doi.org/10.5194/bg-17-6081-2020, https://doi.org/10.5194/bg-17-6081-2020, 2020
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The adverse atmospheric environmental conditions do not appear suited for microbial life. We conducted the first global comparative metagenomic analysis to find out if airborne microbial communities might be selected by their ability to resist these adverse conditions. The relatively higher concentration of fungi led to the observation of higher proportions of stress-related functions in air. Fungi might likely resist and survive atmospheric physical stress better than bacteria.
Yanhong Lu, Shunyan Cheung, Ling Chen, Shuh-Ji Kao, Xiaomin Xia, Jianping Gan, Minhan Dai, and Hongbin Liu
Biogeosciences, 17, 6017–6032, https://doi.org/10.5194/bg-17-6017-2020, https://doi.org/10.5194/bg-17-6017-2020, 2020
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Through a comprehensive investigation, we observed differential niche partitioning among diverse ammonia-oxidizing archaea (AOA) sublineages in a typical subtropical estuary. Distinct AOA communities observed at DNA and RNA levels suggested that a strong divergence in ammonia-oxidizing activity among different AOA groups occurs. Our result highlights the importance of identifying major ammonia oxidizers at RNA level in future studies.
Anna-Neva Visser, Scott D. Wankel, Pascal A. Niklaus, James M. Byrne, Andreas A. Kappler, and Moritz F. Lehmann
Biogeosciences, 17, 4355–4374, https://doi.org/10.5194/bg-17-4355-2020, https://doi.org/10.5194/bg-17-4355-2020, 2020
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This study focuses on the chemical reaction between Fe(II) and nitrite, which has been reported to produce high levels of the greenhouse gas N2O. We investigated the extent to which dead biomass and Fe(II) minerals might enhance this reaction. Here, nitrite reduction was highest when both additives were present but less pronounced if only Fe(II) minerals were added. Both reaction systems show distinct differences, rather low N2O levels, and indicated the abiotic production of N2.
Lisa Tanet, Séverine Martini, Laurie Casalot, and Christian Tamburini
Biogeosciences, 17, 3757–3778, https://doi.org/10.5194/bg-17-3757-2020, https://doi.org/10.5194/bg-17-3757-2020, 2020
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Bioluminescent bacteria, the most abundant light-emitting organisms in the ocean, can be free-living, be symbiotic or colonize organic particles. This review suggests that they act as a visual target and may indirectly influence the sequestration of biogenic carbon in oceans by increasing the attraction rate for consumers. We summarize the instrumentation available to quantify this impact in future studies and propose synthetic figures integrating these ecological and biogeochemical concepts.
Michael Lintner, Bianca Biedrawa, Julia Wukovits, Wolfgang Wanek, and Petra Heinz
Biogeosciences, 17, 3723–3732, https://doi.org/10.5194/bg-17-3723-2020, https://doi.org/10.5194/bg-17-3723-2020, 2020
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Foraminifera are unicellular marine organisms that play an important role in the marine element cycle. Changes of environmental parameters such as salinity or temperature have a significant impact on the faunal assemblages. Our experiments show that changing salinity in the German Wadden Sea immediately influences the foraminiferal community. It seems that A. tepida is better adapted to salinity fluctuations than H. germanica.
Kathrin Busch, Ulrike Hanz, Furu Mienis, Benjamin Mueller, Andre Franke, Emyr Martyn Roberts, Hans Tore Rapp, and Ute Hentschel
Biogeosciences, 17, 3471–3486, https://doi.org/10.5194/bg-17-3471-2020, https://doi.org/10.5194/bg-17-3471-2020, 2020
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Seamounts are globally abundant submarine structures that offer great potential to study the impacts and interactions of environmental gradients at a single geographic location. In an exemplary way, we describe potential mechanisms by which a seamount can affect the structure of pelagic and benthic (sponge-)associated microbial communities. We conclude that the geology, physical oceanography, biogeochemistry, and microbiology of seamounts are even more closely linked than currently appreciated.
Alexander Bratek, Justus E. E. van
Beusekom, Andreas Neumann, Tina Sanders, Jana Friedrich, Kay-Christian Emeis, and Kirstin Dähnke
Biogeosciences, 17, 2839–2851, https://doi.org/10.5194/bg-17-2839-2020, https://doi.org/10.5194/bg-17-2839-2020, 2020
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The following paper highlights the importance of benthic N-transformation rates in different sediment types in the southern North Sea as a source of fixed nitrogen for primary producers and also as a sink of fixed nitrogen. Sedimentary fluxes of dissolved inorganic nitrogen support ∼7 to 59 % of the average annual primary production. Semi-permeable and permeable sediments contribute ∼68 % of the total benthic N2 production rates, counteracting eutrophication in the southern North Sea.
Sabine Haalboom, David M. Price, Furu Mienis, Judith D. L. van Bleijswijk, Henko C. de Stigter, Harry J. Witte, Gert-Jan Reichart, and Gerard C. A. Duineveld
Biogeosciences, 17, 2499–2519, https://doi.org/10.5194/bg-17-2499-2020, https://doi.org/10.5194/bg-17-2499-2020, 2020
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Mineral mining in deep-sea hydrothermal settings will lead to the formation of plumes of fine-grained, chemically reactive, suspended matter. Understanding how natural hydrothermal plumes evolve as they disperse from their source, and how they affect their surrounding environment, may help in characterising the behaviour of the diluted part of mining plumes. The natural plume provided a heterogeneous, geochemically enriched habitat conducive to the development of a distinct microbial ecology.
Noelle A. Held, Eric A. Webb, Matthew M. McIlvin, David A. Hutchins, Natalie R. Cohen, Dawn M. Moran, Korinna Kunde, Maeve C. Lohan, Claire Mahaffey, E. Malcolm S. Woodward, and Mak A. Saito
Biogeosciences, 17, 2537–2551, https://doi.org/10.5194/bg-17-2537-2020, https://doi.org/10.5194/bg-17-2537-2020, 2020
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Trichodesmium is a globally important marine nitrogen fixer that stimulates primary production in the surface ocean. We surveyed metaproteomes of Trichodesmium populations across the North Atlantic and other oceans, and we found that they experience simultaneous phosphate and iron stress because of the biophysical limits of nutrient uptake. Importantly, nitrogenase was most abundant during co-stress, indicating the potential importance of this phenotype to global nitrogen and carbon cycling.
Helmke Hepach, Claire Hughes, Karen Hogg, Susannah Collings, and Rosie Chance
Biogeosciences, 17, 2453–2471, https://doi.org/10.5194/bg-17-2453-2020, https://doi.org/10.5194/bg-17-2453-2020, 2020
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Tropospheric iodine takes part in numerous atmospheric chemical cycles, including tropospheric ozone destruction and aerosol formation. Due to its significance for atmospheric processes, it is crucial to constrain its sources and sinks. This paper aims at investigating and understanding features of biogenic iodate-to-iodide reduction in microalgal monocultures. We find that phytoplankton senescence may play a crucial role in the release of iodide to the marine environment.
Roger D. Finlay, Shahid Mahmood, Nicholas Rosenstock, Emile B. Bolou-Bi, Stephan J. Köhler, Zaenab Fahad, Anna Rosling, Håkan Wallander, Salim Belyazid, Kevin Bishop, and Bin Lian
Biogeosciences, 17, 1507–1533, https://doi.org/10.5194/bg-17-1507-2020, https://doi.org/10.5194/bg-17-1507-2020, 2020
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Effects of biological activity on mineral weathering operate at scales ranging from short-term, microscopic interactions to global, evolutionary timescale processes. Microorganisms have had well-documented effects at large spatio-temporal scales, but to establish the quantitative significance of microscopic measurements for field-scale processes, higher-resolution studies of liquid chemistry at local weathering sites and improved upscaling to soil-scale dissolution rates are still required.
Christine Rooks, James Kar-Hei Fang, Pål Tore Mørkved, Rui Zhao, Hans Tore Rapp, Joana R. Xavier, and Friederike Hoffmann
Biogeosciences, 17, 1231–1245, https://doi.org/10.5194/bg-17-1231-2020, https://doi.org/10.5194/bg-17-1231-2020, 2020
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Sponge grounds are known as nutrient sources, providing nitrate and ammonium to the ocean. We found that they also can do the opposite: in six species from Arctic and North Atlantic sponge grounds, we measured high rates of denitrification, which remove these nutrients from the sea. Rates were highest when the sponge tissue got low in oxygen, which happens when sponges stop pumping because of stress. Sponge grounds may become nutrient sinks when exposed to stress.
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