Articles | Volume 22, issue 1
https://doi.org/10.5194/bg-22-71-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/bg-22-71-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
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08 Jan 2025
Research article | Highlight paper |
| 08 Jan 2025
| 08 Jan 2025
Particle fluxes by subtropical pelagic communities under ocean alkalinity enhancement
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany
Jan Taucher
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany
Silvan Urs Goldenberg
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany
Moritz Baumann
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany
Kristian Spilling
Marine and Freshwater Solutions, Finnish Environment Institute, Helsinki, Finland
Centre for Coastal Research, University of Agder, Kristiansand, Norway
Andrea Noche-Ferreira
Centre for Coastal Research, University of Agder, Kristiansand, Norway
Department of Natural Sciences, University of Agder, Kristiansand, Norway
Mari Vanharanta
Marine and Freshwater Solutions, Finnish Environment Institute, Helsinki, Finland
Tvärminne Zoological Station, University of Helsinki, Hanko, Finland
Ulf Riebesell
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany
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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.
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.
Giulia Faucher, Mathias Haunost, Allanah Joy Paul, Anne Ulrike Christiane Tietz, and Ulf Riebesell
EGUsphere, https://doi.org/10.5194/egusphere-2024-2201, https://doi.org/10.5194/egusphere-2024-2201, 2024
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OAE is being evaluated for its capacity to absorb atmospheric CO2 in the ocean, storing it long-term to mitigate climate change. As researchers plan for field tests to gain practical insights into OAE, sharing knowledge on its environmental impact on marine ecosystems is urgent. Our study examined NaOH-induced alkalinity increases on Emiliania huxleyi, a key coccolithophore species. We found that to prevent negative impacts on this species, the increase in ΔTA should not exceed 600 µmol kg-1.
Mathilde Dugenne, Marco Corrales-Ugalde, Jessica Y. Luo, Rainer Kiko, Todd D. O'Brien, Jean-Olivier Irisson, Fabien Lombard, Lars Stemmann, Charles Stock, Clarissa R. Anderson, Marcel Babin, Nagib Bhairy, Sophie Bonnet, Francois Carlotti, Astrid Cornils, E. Taylor Crockford, Patrick Daniel, Corinne Desnos, Laetitia Drago, Amanda Elineau, Alexis Fischer, Nina Grandrémy, Pierre-Luc Grondin, Lionel Guidi, Cecile Guieu, Helena Hauss, Kendra Hayashi, Jenny A. Huggett, Laetitia Jalabert, Lee Karp-Boss, Kasia M. Kenitz, Raphael M. Kudela, Magali Lescot, Claudie Marec, Andrew McDonnell, Zoe Mériguet, Barbara Niehoff, Margaux Noyon, Thelma Panaïotis, Emily Peacock, Marc Picheral, Emilie Riquier, Collin Roesler, Jean-Baptiste Romagnan, Heidi M. Sosik, Gretchen Spencer, Jan Taucher, Chloé Tilliette, and Marion Vilain
Earth Syst. Sci. Data, 16, 2971–2999, https://doi.org/10.5194/essd-16-2971-2024, https://doi.org/10.5194/essd-16-2971-2024, 2024
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Plankton and particles influence carbon cycling and energy flow in marine ecosystems. We used three types of novel plankton imaging systems to obtain size measurements from a range of plankton and particle sizes and across all major oceans. Data were compiled and cross-calibrated from many thousands of images, showing seasonal and spatial changes in particle size structure in different ocean basins. These datasets form the first release of the Pelagic Size Structure database (PSSdb).
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.
Librada Ramírez, Leonardo J. Pozzo-Pirotta, Aja Trebec, Víctor Manzanares-Vázquez, José L. Díez, Javier Arístegui, Ulf Riebesell, Stephen D. Archer, and María Segovia
EGUsphere, https://doi.org/10.5194/egusphere-2024-847, https://doi.org/10.5194/egusphere-2024-847, 2024
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We studied the potential effects of increasing ocean alkalinity on a natural plankton community in subtropical waters of the Atlantic near Gran Canaria, Spain. Alkalinity is the capacity of water to resist acidification and plankton are usually microscopic plants (phytoplankton) and animals (zooplankton), often less than 2,5 cm in length. This study suggests that increasing ocean alkalinity did not have a significant negative impact on the studied plankton community.
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.
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.
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.
Patricia Ayón Dejo, Elda Luz Pinedo Arteaga, Anna Schukat, Jan Taucher, Rainer Kiko, Helena Hauss, Sabrina Dorschner, Wilhelm Hagen, Mariona Segura-Noguera, and Silke Lischka
Biogeosciences, 20, 945–969, https://doi.org/10.5194/bg-20-945-2023, https://doi.org/10.5194/bg-20-945-2023, 2023
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Ocean upwelling regions are highly productive. With ocean warming, severe changes in upwelling frequency and/or intensity and expansion of accompanying oxygen minimum zones are projected. In a field experiment off Peru, we investigated how different upwelling intensities affect the pelagic food web and found failed reproduction of dominant zooplankton. The changes projected could severely impact the reproductive success of zooplankton communities and the pelagic food web in upwelling regions.
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.
Rainer Kiko, Marc Picheral, David Antoine, Marcel Babin, Léo Berline, Tristan Biard, Emmanuel Boss, Peter Brandt, Francois Carlotti, Svenja Christiansen, Laurent Coppola, Leandro de la Cruz, Emilie Diamond-Riquier, Xavier Durrieu de Madron, Amanda Elineau, Gabriel Gorsky, Lionel Guidi, Helena Hauss, Jean-Olivier Irisson, Lee Karp-Boss, Johannes Karstensen, Dong-gyun Kim, Rachel M. Lekanoff, Fabien Lombard, Rubens M. Lopes, Claudie Marec, Andrew M. P. McDonnell, Daniela Niemeyer, Margaux Noyon, Stephanie H. O'Daly, Mark D. Ohman, Jessica L. Pretty, Andreas Rogge, Sarah Searson, Masashi Shibata, Yuji Tanaka, Toste Tanhua, Jan Taucher, Emilia Trudnowska, Jessica S. Turner, Anya Waite, and Lars Stemmann
Earth Syst. Sci. Data, 14, 4315–4337, https://doi.org/10.5194/essd-14-4315-2022, https://doi.org/10.5194/essd-14-4315-2022, 2022
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The term
marine particlescomprises detrital aggregates; fecal pellets; bacterioplankton, phytoplankton and zooplankton; and even fish. Here, we present a global dataset that contains 8805 vertical particle size distribution profiles obtained with Underwater Vision Profiler 5 (UVP5) camera systems. These data are valuable to the scientific community, as they can be used to constrain important biogeochemical processes in the ocean, such as the flux of carbon to the deep sea.
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.
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.
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.
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.
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.
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.
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.
Thomas Hornick, Lennart T. Bach, Katharine J. Crawfurd, Kristian Spilling, Eric P. Achterberg, Jason N. Woodhouse, Kai G. Schulz, Corina P. D. Brussaard, Ulf Riebesell, and Hans-Peter Grossart
Biogeosciences, 14, 1–15, https://doi.org/10.5194/bg-14-1-2017, https://doi.org/10.5194/bg-14-1-2017, 2017
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.
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.
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
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
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
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
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
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
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
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
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
Earth System Science/Response to Global Change: Climate Change
Responses of field-grown maize to different soil types, water regimes, and contrasting vapor pressure deficit
Effect of the 2022 summer drought across forest types in Europe
Effect of terrestrial nutrient limitation on the estimation of the remaining carbon budget
Projected changes in forest fire season, the number of fires, and burnt area in Fennoscandia by 2100
New ozone–nitrogen model shows early senescence onset is the primary cause of ozone-induced reduction in grain quality of wheat
Ocean alkalinity enhancement approaches and the predictability of runaway precipitation processes: results of an experimental study to determine critical alkalinity ranges for safe and sustainable application scenarios
Long-term impacts of global temperature stabilization and overshoot on exploited marine species
Variations of polyphenols and carbohydrates of Emiliania huxleyi grown under simulated ocean acidification conditions
Modelling the nutritional implications of ozone on wheat protein and amino acids
Global and regional hydrological impacts of global forest expansion
The biological and preformed carbon pumps in perpetually slower and warmer oceans
The Effectiveness of Agricultural Carbon Dioxide Removal using the University of Victoria Earth System Climate Model
Toward more robust NPP projections in the North Atlantic Ocean
The Southern Ocean as the climate's freight train – driving ongoing global warming under zero-emission scenarios with ACCESS-ESM1.5
Review and syntheses: Ocean alkalinity enhancement and carbon dioxide removal through coastal enhanced silicate weathering with olivine
Mapping the future afforestation distribution of China constrained by a national afforestation plan and climate change
Southern Ocean phytoplankton under climate change: a shifting balance of bottom-up and top-down control
Coherency and time lag analyses between MODIS vegetation indices and climate across forests and grasslands in the European temperate zone
Direct foliar phosphorus uptake from wildfire ash
Unifying framework for assessing sensitivity for marine calcifiers to ocean alkalinity enhancement identifies winners, losers and biological thresholds – importance of caution with precautionary principle
The effect of forest cover changes on the regional climate conditions in Europe during the period 1986–2015
Carbon cycle feedbacks in an idealized simulation and a scenario simulation of negative emissions in CMIP6 Earth system models
Divergent responses of evergreen needle-leaf forests in Europe to the 2020 warm winter
Spatiotemporal heterogeneity in the increase in ocean acidity extremes in the northeastern Pacific
Anthropogenic climate change drives non-stationary phytoplankton internal variability
The response of wildfire regimes to Last Glacial Maximum carbon dioxide and climate
Simulated responses of soil carbon to climate change in CMIP6 Earth system models: the role of false priming
Alkalinity biases in CMIP6 Earth system models and implications for simulated CO2 drawdown via artificial alkalinity enhancement
Experiments of the efficacy of tree ring blue intensity as a climate proxy in central and western China
Burned area and carbon emissions across northwestern boreal North America from 2001–2019
Quantifying land carbon cycle feedbacks under negative CO2 emissions
The potential of an increased deciduous forest fraction to mitigate the effects of heat extremes in Europe
Ideas and perspectives: Alleviation of functional limitations by soil organisms is key to climate feedbacks from arctic soils
A comparison of the climate and carbon cycle effects of carbon removal by afforestation and an equivalent reduction in fossil fuel emissions
Stability of alkalinity in ocean alkalinity enhancement (OAE) approaches – consequences for durability of CO2 storage
Ideas and perspectives: Land–ocean connectivity through groundwater
Bioclimatic change as a function of global warming from CMIP6 climate projections
Reconciling different approaches to quantifying land surface temperature impacts of afforestation using satellite observations
Drivers of intermodel uncertainty in land carbon sink projections
Reviews and syntheses: A framework to observe, understand and project ecosystem response to environmental change in the East Antarctic Southern Ocean
Acidification impacts and acclimation potential of Caribbean benthic foraminifera assemblages in naturally discharging low-pH water
Monitoring vegetation condition using microwave remote sensing: the standardized vegetation optical depth index (SVODI)
Evaluation of soil carbon simulation in CMIP6 Earth system models
Diazotrophy as a key driver of the response of marine net primary productivity to climate change
Impact of negative and positive CO2 emissions on global warming metrics using an ensemble of Earth system model simulations
Acidification, deoxygenation, and nutrient and biomass declines in a warming Mediterranean Sea
Ocean alkalinity enhancement – avoiding runaway CaCO3 precipitation during quick and hydrated lime dissolution
Assessment of the impacts of biological nitrogen fixation structural uncertainty in CMIP6 earth system models
Soil carbon loss in warmed subarctic grasslands is rapid and restricted to topsoil
The European forest carbon budget under future climate conditions and current management practices
Thuy Huu Nguyen, Thomas Gaiser, Jan Vanderborght, Andrea Schnepf, Felix Bauer, Anja Klotzsche, Lena Lärm, Hubert Hüging, and Frank Ewert
Biogeosciences, 21, 5495–5515, https://doi.org/10.5194/bg-21-5495-2024, https://doi.org/10.5194/bg-21-5495-2024, 2024
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Leaf water potential was at certain thresholds, depending on soil type, water treatment, and weather conditions. In rainfed plots, the lower water availability in the stony soil resulted in fewer roots with a higher root tissue conductance than the silty soil. In the silty soil, higher stress in the rainfed soil led to more roots with a lower root tissue conductance than in the irrigated plot. Crop responses to water stress can be opposite, depending on soil water conditions that are compared.
Mana Gharun, Ankit Shekhar, Jingfeng Xiao, Xing Li, and Nina Buchmann
Biogeosciences, 21, 5481–5494, https://doi.org/10.5194/bg-21-5481-2024, https://doi.org/10.5194/bg-21-5481-2024, 2024
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In 2022, Europe's forests faced unprecedented dry conditions. Our study aimed to understand how different forest types respond to extreme drought. Using meteorological data and satellite imagery, we compared 2022 with two previous extreme years, 2003 and 2018. Despite less severe drought in 2022, forests showed a 30 % greater decline in photosynthesis compared to 2018 and 60 % more than 2003. This suggests an alarming level of vulnerability of forests across Europe to more frequent droughts.
Makcim L. De Sisto and Andrew H. MacDougall
Biogeosciences, 21, 4853–4873, https://doi.org/10.5194/bg-21-4853-2024, https://doi.org/10.5194/bg-21-4853-2024, 2024
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The remaining carbon budget (RCB) represents the allowable future CO2 emissions before a temperature target is reached. Understanding the uncertainty in the RCB is critical for effective climate regulation and policy-making. One major source of uncertainty is the representation of the carbon cycle in Earth system models. We assessed how nutrient limitation affects the estimation of the RCB. We found a reduction in the estimated RCB when nutrient limitation is taken into account.
Outi Kinnunen, Leif Backman, Juha Aalto, Tuula Aalto, and Tiina Markkanen
Biogeosciences, 21, 4739–4763, https://doi.org/10.5194/bg-21-4739-2024, https://doi.org/10.5194/bg-21-4739-2024, 2024
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Climate change is expected to increase the risk of forest fires. Ecosystem process model simulations are used to project changes in fire occurrence in Fennoscandia under six climate projections. The findings suggest a longer fire season, more fires, and an increase in burnt area towards the end of the century.
Jo Cook, Clare Brewster, Felicity Hayes, Nathan Booth, Sam Bland, Pritha Pande, Samarthia Thankappan, Håkan Pleijel, and Lisa Emberson
Biogeosciences, 21, 4809–4835, https://doi.org/10.5194/bg-21-4809-2024, https://doi.org/10.5194/bg-21-4809-2024, 2024
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At ground level, the air pollutant ozone (O3) damages wheat yield and quality. We modified the DO3SE-Crop model to simulate O3 effects on wheat quality and identified onset of leaf death as the key process affecting wheat quality upon O3 exposure. This aligns with expectations, as the onset of leaf death aids nutrient transfer from leaves to grains. Breeders should prioritize wheat varieties resistant to protein loss from delayed leaf death, to maintain yield and quality under O3 exposure.
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.
Anne L. Morée, Fabrice Lacroix, William W. L. Cheung, and Thomas L. Frölicher
EGUsphere, https://doi.org/10.5194/egusphere-2024-3090, https://doi.org/10.5194/egusphere-2024-3090, 2024
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Using novel Earth system model simulations and applying the Aerobic Growth Index, we show that only about half of the habitat loss for marine species is realized when temperature stabilization is initially reached. The maximum habitat loss happens over a century after peak warming in an overshoot scenario peaking at 2 °C before stabilizing at 1.5 °C. We also emphasize that species adaptation may play a key role in mitigating the long-term impacts of temperature stabilization and overshoot.
Milagros Rico, Paula Santiago-Díaz, Guillermo Samperio-Ramos, Melchor González-Dávila, and Juana Magdalena Santana-Casiano
Biogeosciences, 21, 4381–4394, https://doi.org/10.5194/bg-21-4381-2024, https://doi.org/10.5194/bg-21-4381-2024, 2024
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Changes in pH generate stress conditions, either because high pH drastically decreases the availability of trace metals such as Fe(II), a restrictive element for primary productivity, or because reactive oxygen species are increased with low pH. The metabolic functions and composition of microalgae can be affected. These modifications in metabolites are potential factors leading to readjustments in phytoplankton community structure and diversity and possible alteration in marine ecosystems.
Jo Cook, Durgesh Singh Yadav, Felicity Hayes, Nathan Booth, Sam Bland, Pritha Pande, Samarthia Thankappan, and Lisa Emberson
EGUsphere, https://doi.org/10.5194/egusphere-2024-2968, https://doi.org/10.5194/egusphere-2024-2968, 2024
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Ozone (O3) pollution reduces wheat yields and quality in India, affecting amino acids essential for nutrition, like lysine and methionine. Here, we improve the DO3SE-CropN model to simulate wheat’s protective processes against O3 and their impact on protein and amino acid concentrations. While the model captures O3-induced yield losses, it underestimates amino acid reductions. Further research is needed to refine the model, enabling future risk assessments of O3's impact on yields and nutrition.
James A. King, James Weber, Peter Lawrence, Stephanie Roe, Abigail L. S. Swann, and Maria Val Martin
Biogeosciences, 21, 3883–3902, https://doi.org/10.5194/bg-21-3883-2024, https://doi.org/10.5194/bg-21-3883-2024, 2024
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Tackling climate change by adding, restoring, or enhancing forests is gaining global support. However, it is important to investigate the broader implications of this. We used a computer model of the Earth to investigate a future where tree cover expanded as much as possible. We found that some tropical areas were cooler because of trees pumping water into the atmosphere, but this also led to soil and rivers drying. This is important because it might be harder to maintain forests as a result.
Benoît Pasquier, Mark Holzer, and Matthew A. Chamberlain
Biogeosciences, 21, 3373–3400, https://doi.org/10.5194/bg-21-3373-2024, https://doi.org/10.5194/bg-21-3373-2024, 2024
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How do perpetually slower and warmer oceans sequester carbon? Compared to the preindustrial state, we find that biological productivity declines despite warming-stimulated growth because of a lower nutrient supply from depth. This throttles the biological carbon pump, which still sequesters more carbon because it takes longer to return to the surface. The deep ocean is isolated from the surface, allowing more carbon from the atmosphere to pass through the ocean without contributing to biology.
Rebecca Chloe Evans and H. Damon Matthews
EGUsphere, https://doi.org/10.5194/egusphere-2024-1810, https://doi.org/10.5194/egusphere-2024-1810, 2024
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To mitigate our impact on the climate, research suggests that we will need to both drastically reduce emissions and perform carbon dioxide removal (CDR). We simulated future climates under three emissions scenarios, in which we removed some carbon from the air and put it into agricultural soil at varying rates. We found that agricultural CDR is much more effective at reducing global temperatures if done in a low emissions scenario and at a high rate, and it becomes less effective with time.
Stéphane Doléac, Marina Lévy, Roy El Hourany, and Laurent Bopp
EGUsphere, https://doi.org/10.5194/egusphere-2024-1820, https://doi.org/10.5194/egusphere-2024-1820, 2024
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Phytoplankton net primary production (NPP) is influenced by many processes, and their representation varies across Earth-system models. This leads to differing projections for NPP's future under climate change, especially in the North Atlantic. To address this, we identified and assessed the processes controlling NPP in each model. This assessment helped us select the most reliable models, significantly improving NPP projections in the region.
Matthew A. Chamberlain, Tilo Ziehn, and Rachel M. Law
Biogeosciences, 21, 3053–3073, https://doi.org/10.5194/bg-21-3053-2024, https://doi.org/10.5194/bg-21-3053-2024, 2024
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This paper explores the climate processes that drive increasing global average temperatures in zero-emission commitment (ZEC) simulations despite decreasing atmospheric CO2. ACCESS-ESM1.5 shows the Southern Ocean to continue to warm locally in all ZEC simulations. In ZEC simulations that start after the emission of more than 1000 Pg of carbon, the influence of the Southern Ocean increases the global temperature.
Luna J. J. Geerts, Astrid Hylén, and Filip J. R. Meysman
EGUsphere, https://doi.org/10.5194/egusphere-2024-1824, https://doi.org/10.5194/egusphere-2024-1824, 2024
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Coastal enhanced silicate weathering (CESW) with olivine is a promising method for capturing CO2 from the atmosphere, yet studies in field conditions are lacking. We bridge the gap between theoretical studies and the real-world environment by estimating the predictability of CESW parameters and identifying aspects to consider when applying CESW. A major source of uncertainty is the lack of experimental studies with sediment, which can heavily influence the speed and efficiency of CO2 drawdown.
Shuaifeng Song, Xuezhen Zhang, and Xiaodong Yan
Biogeosciences, 21, 2839–2858, https://doi.org/10.5194/bg-21-2839-2024, https://doi.org/10.5194/bg-21-2839-2024, 2024
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We mapped the distribution of future potential afforestation regions based on future high-resolution climate data and climate–vegetation models. After considering the national afforestation policy and climate change, we found that the future potential afforestation region was mainly located around and to the east of the Hu Line. This study provides a dataset for exploring the effects of future afforestation.
Tianfei Xue, Jens Terhaar, A. E. Friederike Prowe, Thomas L. Frölicher, Andreas Oschlies, and Ivy Frenger
Biogeosciences, 21, 2473–2491, https://doi.org/10.5194/bg-21-2473-2024, https://doi.org/10.5194/bg-21-2473-2024, 2024
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Phytoplankton play a crucial role in marine ecosystems. However, climate change's impact on phytoplankton biomass remains uncertain, particularly in the Southern Ocean. In this region, phytoplankton biomass within the water column is likely to remain stable in response to climate change, as supported by models. This stability arises from a shallower mixed layer, favoring phytoplankton growth but also increasing zooplankton grazing due to phytoplankton concentration near the surface.
Kinga Kulesza and Agata Hościło
Biogeosciences, 21, 2509–2527, https://doi.org/10.5194/bg-21-2509-2024, https://doi.org/10.5194/bg-21-2509-2024, 2024
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We present coherence and time lags in spectral response of three vegetation types in the European temperate zone to the influencing meteorological factors and teleconnection indices for the period 2002–2022. Vegetation condition in broadleaved forest, coniferous forest and pastures was measured with MODIS NDVI and EVI, and the coherence between NDVI and EVI and meteorological elements was described using the methods of wavelet coherence and Pearson’s linear correlation with time lag.
Anton Lokshin, Daniel Palchan, and Avner Gross
Biogeosciences, 21, 2355–2365, https://doi.org/10.5194/bg-21-2355-2024, https://doi.org/10.5194/bg-21-2355-2024, 2024
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Ash particles from wildfires are rich in phosphorus (P), a crucial nutrient that constitutes a limiting factor in 43 % of the world's land ecosystems. We hypothesize that wildfire ash could directly contribute to plant nutrition. We find that fire ash application boosts the growth of plants, but the only way plants can uptake P from fire ash is through the foliar uptake pathway and not through the roots. The fertilization impact of fire ash was also maintained under elevated levels of CO2.
Nina Bednaršek, Greg Pelletier, Hanna van de Mortel, Marisol García-Reyes, Richard Feely, and Andrew Dickson
EGUsphere, https://doi.org/10.5194/egusphere-2024-947, https://doi.org/10.5194/egusphere-2024-947, 2024
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The environmental impacts of ocean alkalinity enhancement (OAE) are unknown. A conceptual framework was developed showing 40 % of species to respond positively, 20 % negatively and 40 % with neutral response upon alkalinity addition. Biological thresholds were found between 10 to 500 µmol/kg NaOH addition, emphasizing lab experiments to be conducted at lower dosages. A precautionary approach is warranted to avoid potential risks.
Marcus Breil, Vanessa K. M. Schneider, and Joaquim G. Pinto
Biogeosciences, 21, 811–824, https://doi.org/10.5194/bg-21-811-2024, https://doi.org/10.5194/bg-21-811-2024, 2024
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The general impact of afforestation on the regional climate conditions in Europe during the period 1986–2015 is investigated. For this purpose, a regional climate model simulation is performed, in which afforestation during this period is considered, and results are compared to a simulation in which this is not the case. Results show that afforestation had discernible impacts on the climate change signal in Europe, which may have mitigated the local warming trend, especially in summer in Europe.
Ali Asaadi, Jörg Schwinger, Hanna Lee, Jerry Tjiputra, Vivek Arora, Roland Séférian, Spencer Liddicoat, Tomohiro Hajima, Yeray Santana-Falcón, and Chris D. Jones
Biogeosciences, 21, 411–435, https://doi.org/10.5194/bg-21-411-2024, https://doi.org/10.5194/bg-21-411-2024, 2024
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Carbon cycle feedback metrics are employed to assess phases of positive and negative CO2 emissions. When emissions become negative, we find that the model disagreement in feedback metrics increases more strongly than expected from the assumption that the uncertainties accumulate linearly with time. The geographical patterns of such metrics over land highlight that differences in response between tropical/subtropical and temperate/boreal ecosystems are a major source of model disagreement.
Mana Gharun, Ankit Shekhar, Lukas Hörtnagl, Luana Krebs, Nicola Arriga, Mirco Migliavacca, Marilyn Roland, Bert Gielen, Leonardo Montagnani, Enrico Tomelleri, Ladislav Šigut, Matthias Peichl, Peng Zhao, Marius Schmidt, Thomas Grünwald, Mika Korkiakoski, Annalea Lohila, and Nina Buchmann
EGUsphere, https://doi.org/10.5194/egusphere-2023-2964, https://doi.org/10.5194/egusphere-2023-2964, 2024
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Effect of winter warming on forest CO2 fluxes has rarely been investigated. We tested the effect of the warm winter in 2020 on the forest CO2 fluxes across 14 sites in Europe and found that in colder sites net ecosystem productivity (NEP) declined during the warm winter, while in the warmer sites NEP increased. Warming leads to increased respiration fluxes but if not translated into a direct warming of the soil might not enhance productivity, if the soil within the rooting zone remains frozen.
Flora Desmet, Matthias Münnich, and Nicolas Gruber
Biogeosciences, 20, 5151–5175, https://doi.org/10.5194/bg-20-5151-2023, https://doi.org/10.5194/bg-20-5151-2023, 2023
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Ocean acidity extremes in the upper 250 m depth of the northeastern Pacific rapidly increase with atmospheric CO2 rise, which is worrisome for marine organisms that rapidly experience pH levels outside their local environmental conditions. Presented research shows the spatiotemporal heterogeneity in this increase between regions and depths. In particular, the subsurface increase is substantially slowed down by the presence of mesoscale eddies, often not resolved in Earth system models.
Geneviève W. Elsworth, Nicole S. Lovenduski, Kristen M. Krumhardt, Thomas M. Marchitto, and Sarah Schlunegger
Biogeosciences, 20, 4477–4490, https://doi.org/10.5194/bg-20-4477-2023, https://doi.org/10.5194/bg-20-4477-2023, 2023
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Anthropogenic climate change will influence marine phytoplankton over the coming century. Here, we quantify the influence of anthropogenic climate change on marine phytoplankton internal variability using an Earth system model ensemble and identify a decline in global phytoplankton biomass variance with warming. Our results suggest that climate mitigation efforts that account for marine phytoplankton changes should also consider changes in phytoplankton variance driven by anthropogenic warming.
Olivia Haas, Iain Colin Prentice, and Sandy P. Harrison
Biogeosciences, 20, 3981–3995, https://doi.org/10.5194/bg-20-3981-2023, https://doi.org/10.5194/bg-20-3981-2023, 2023
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We quantify the impact of CO2 and climate on global patterns of burnt area, fire size, and intensity under Last Glacial Maximum (LGM) conditions using three climate scenarios. Climate change alone did not produce the observed LGM reduction in burnt area, but low CO2 did through reducing vegetation productivity. Fire intensity was sensitive to CO2 but strongly affected by changes in atmospheric dryness. Low CO2 caused smaller fires; climate had the opposite effect except in the driest scenario.
Rebecca M. Varney, Sarah E. Chadburn, Eleanor J. Burke, Simon Jones, Andy J. Wiltshire, and Peter M. Cox
Biogeosciences, 20, 3767–3790, https://doi.org/10.5194/bg-20-3767-2023, https://doi.org/10.5194/bg-20-3767-2023, 2023
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This study evaluates soil carbon projections during the 21st century in CMIP6 Earth system models. In general, we find a reduced spread of changes in global soil carbon in CMIP6 compared to the previous CMIP5 generation. The reduced CMIP6 spread arises from an emergent relationship between soil carbon changes due to change in plant productivity and soil carbon changes due to changes in turnover time. We show that this relationship is consistent with false priming under transient climate change.
Claudia Hinrichs, Peter Köhler, Christoph Völker, and Judith Hauck
Biogeosciences, 20, 3717–3735, https://doi.org/10.5194/bg-20-3717-2023, https://doi.org/10.5194/bg-20-3717-2023, 2023
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This study evaluated the alkalinity distribution in 14 climate models and found that most models underestimate alkalinity at the surface and overestimate it in the deeper ocean. It highlights the need for better understanding and quantification of processes driving alkalinity distribution and calcium carbonate dissolution and the importance of accounting for biases in model results when evaluating potential ocean alkalinity enhancement experiments.
Yonghong Zheng, Huanfeng Shen, Rory Abernethy, and Rob Wilson
Biogeosciences, 20, 3481–3490, https://doi.org/10.5194/bg-20-3481-2023, https://doi.org/10.5194/bg-20-3481-2023, 2023
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Investigations in central and western China show that tree ring inverted latewood intensity expresses a strong positive relationship with growing-season temperatures, indicating exciting potential for regions south of 30° N that are traditionally not targeted for temperature reconstructions. Earlywood BI also shows good potential to reconstruct hydroclimate parameters in some humid areas and will enhance ring-width-based hydroclimate reconstructions in the future.
Stefano Potter, Sol Cooperdock, Sander Veraverbeke, Xanthe Walker, Michelle C. Mack, Scott J. Goetz, Jennifer Baltzer, Laura Bourgeau-Chavez, Arden Burrell, Catherine Dieleman, Nancy French, Stijn Hantson, Elizabeth E. Hoy, Liza Jenkins, Jill F. Johnstone, Evan S. Kane, Susan M. Natali, James T. Randerson, Merritt R. Turetsky, Ellen Whitman, Elizabeth Wiggins, and Brendan M. Rogers
Biogeosciences, 20, 2785–2804, https://doi.org/10.5194/bg-20-2785-2023, https://doi.org/10.5194/bg-20-2785-2023, 2023
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Here we developed a new burned-area detection algorithm between 2001–2019 across Alaska and Canada at 500 m resolution. We estimate 2.37 Mha burned annually between 2001–2019 over the domain, emitting 79.3 Tg C per year, with a mean combustion rate of 3.13 kg C m−2. We found larger-fire years were generally associated with greater mean combustion. The burned-area and combustion datasets described here can be used for local- to continental-scale applications of boreal fire science.
V. Rachel Chimuka, Claude-Michel Nzotungicimpaye, and Kirsten Zickfeld
Biogeosciences, 20, 2283–2299, https://doi.org/10.5194/bg-20-2283-2023, https://doi.org/10.5194/bg-20-2283-2023, 2023
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We propose a new method to quantify carbon cycle feedbacks under negative CO2 emissions. Our method isolates the lagged carbon cycle response to preceding positive emissions from the response to negative emissions. Our findings suggest that feedback parameters calculated with the novel approach are larger than those calculated with the conventional approach whereby carbon cycle inertia is not corrected for, with implications for the effectiveness of carbon dioxide removal in reducing CO2 levels.
Marcus Breil, Annabell Weber, and Joaquim G. Pinto
Biogeosciences, 20, 2237–2250, https://doi.org/10.5194/bg-20-2237-2023, https://doi.org/10.5194/bg-20-2237-2023, 2023
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A promising strategy for mitigating burdens of heat extremes in Europe is to replace dark coniferous forests with brighter deciduous forests. The consequence of this would be reduced absorption of solar radiation, which should reduce the intensities of heat periods. In this study, we show that deciduous forests have a certain cooling effect on heat period intensities in Europe. However, the magnitude of the temperature reduction is quite small.
Gesche Blume-Werry, Jonatan Klaminder, Eveline J. Krab, and Sylvain Monteux
Biogeosciences, 20, 1979–1990, https://doi.org/10.5194/bg-20-1979-2023, https://doi.org/10.5194/bg-20-1979-2023, 2023
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Northern soils store a lot of carbon. Most research has focused on how this carbon storage is regulated by cold temperatures. However, it is soil organisms, from minute bacteria to large earthworms, that decompose the organic material. Novel soil organisms from further south could increase decomposition rates more than climate change does and lead to carbon losses. We therefore advocate for including soil organisms when predicting the fate of soil functions in warming northern ecosystems.
Koramanghat Unnikrishnan Jayakrishnan and Govindasamy Bala
Biogeosciences, 20, 1863–1877, https://doi.org/10.5194/bg-20-1863-2023, https://doi.org/10.5194/bg-20-1863-2023, 2023
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Afforestation and reducing fossil fuel emissions are two important mitigation strategies to reduce the amount of global warming. Our work shows that reducing fossil fuel emissions is relatively more effective than afforestation for the same amount of carbon removed from the atmosphere. However, understanding of the processes that govern the biophysical effects of afforestation should be improved before considering our results for climate policy.
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.
Damian L. Arévalo-Martínez, Amir Haroon, Hermann W. Bange, Ercan Erkul, Marion Jegen, Nils Moosdorf, Jens Schneider von Deimling, Christian Berndt, Michael Ernst Böttcher, Jasper Hoffmann, Volker Liebetrau, Ulf Mallast, Gudrun Massmann, Aaron Micallef, Holly A. Michael, Hendrik Paasche, Wolfgang Rabbel, Isaac Santos, Jan Scholten, Katrin Schwalenberg, Beata Szymczycha, Ariel T. Thomas, Joonas J. Virtasalo, Hannelore Waska, and Bradley A. Weymer
Biogeosciences, 20, 647–662, https://doi.org/10.5194/bg-20-647-2023, https://doi.org/10.5194/bg-20-647-2023, 2023
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Groundwater flows at the land–ocean transition and the extent of freshened groundwater below the seafloor are increasingly relevant in marine sciences, both because they are a highly uncertain term of biogeochemical budgets and due to the emerging interest in the latter as a resource. Here, we discuss our perspectives on future research directions to better understand land–ocean connectivity through groundwater and its potential responses to natural and human-induced environmental changes.
Morgan Sparey, Peter Cox, and Mark S. Williamson
Biogeosciences, 20, 451–488, https://doi.org/10.5194/bg-20-451-2023, https://doi.org/10.5194/bg-20-451-2023, 2023
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Accurate climate models are vital for mitigating climate change; however, projections often disagree. Using Köppen–Geiger bioclimate classifications we show that CMIP6 climate models agree well on the fraction of global land surface that will change classification per degree of global warming. We find that 13 % of land will change climate per degree of warming from 1 to 3 K; thus, stabilising warming at 1.5 rather than 2 K would save over 7.5 million square kilometres from bioclimatic change.
Huanhuan Wang, Chao Yue, and Sebastiaan Luyssaert
Biogeosciences, 20, 75–92, https://doi.org/10.5194/bg-20-75-2023, https://doi.org/10.5194/bg-20-75-2023, 2023
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This study provided a synthesis of three influential methods to quantify afforestation impact on surface temperature. Results showed that actual effect following afforestation was highly dependent on afforestation fraction. When full afforestation is assumed, the actual effect approaches the potential effect. We provided evidence the afforestation faction is a key factor in reconciling different methods and emphasized that it should be considered for surface cooling impacts in policy evaluation.
Ryan S. Padrón, Lukas Gudmundsson, Laibao Liu, Vincent Humphrey, and Sonia I. Seneviratne
Biogeosciences, 19, 5435–5448, https://doi.org/10.5194/bg-19-5435-2022, https://doi.org/10.5194/bg-19-5435-2022, 2022
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The answer to how much carbon land ecosystems are projected to remove from the atmosphere until 2100 is different for each Earth system model. We find that differences across models are primarily explained by the annual land carbon sink dependence on temperature and soil moisture, followed by the dependence on CO2 air concentration, and by average climate conditions. Our insights on why each model projects a relatively high or low land carbon sink can help to reduce the underlying uncertainty.
Julian Gutt, Stefanie Arndt, David Keith Alan Barnes, Horst Bornemann, Thomas Brey, Olaf Eisen, Hauke Flores, Huw Griffiths, Christian Haas, Stefan Hain, Tore Hattermann, Christoph Held, Mario Hoppema, Enrique Isla, Markus Janout, Céline Le Bohec, Heike Link, Felix Christopher Mark, Sebastien Moreau, Scarlett Trimborn, Ilse van Opzeeland, Hans-Otto Pörtner, Fokje Schaafsma, Katharina Teschke, Sandra Tippenhauer, Anton Van de Putte, Mia Wege, Daniel Zitterbart, and Dieter Piepenburg
Biogeosciences, 19, 5313–5342, https://doi.org/10.5194/bg-19-5313-2022, https://doi.org/10.5194/bg-19-5313-2022, 2022
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Long-term ecological observations are key to assess, understand and predict impacts of environmental change on biotas. We present a multidisciplinary framework for such largely lacking investigations in the East Antarctic Southern Ocean, combined with case studies, experimental and modelling work. As climate change is still minor here but is projected to start soon, the timely implementation of this framework provides the unique opportunity to document its ecological impacts from the very onset.
Daniel François, Adina Paytan, Olga Maria Oliveira de Araújo, Ricardo Tadeu Lopes, and Cátia Fernandes Barbosa
Biogeosciences, 19, 5269–5285, https://doi.org/10.5194/bg-19-5269-2022, https://doi.org/10.5194/bg-19-5269-2022, 2022
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Our analysis revealed that under the two most conservative acidification projections foraminifera assemblages did not display considerable changes. However, a significant decrease in species richness was observed when pH decreases to 7.7 pH units, indicating adverse effects under high-acidification scenarios. A micro-CT analysis revealed that calcified tests of Archaias angulatus were of lower density in low pH, suggesting no acclimation capacity for this species.
Leander Moesinger, Ruxandra-Maria Zotta, Robin van der Schalie, Tracy Scanlon, Richard de Jeu, and Wouter Dorigo
Biogeosciences, 19, 5107–5123, https://doi.org/10.5194/bg-19-5107-2022, https://doi.org/10.5194/bg-19-5107-2022, 2022
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The standardized vegetation optical depth index (SVODI) can be used to monitor the vegetation condition, such as whether the vegetation is unusually dry or wet. SVODI has global coverage, spans the past 3 decades and is derived from multiple spaceborne passive microwave sensors of that period. SVODI is based on a new probabilistic merging method that allows the merging of normally distributed data even if the data are not gap-free.
Rebecca M. Varney, Sarah E. Chadburn, Eleanor J. Burke, and Peter M. Cox
Biogeosciences, 19, 4671–4704, https://doi.org/10.5194/bg-19-4671-2022, https://doi.org/10.5194/bg-19-4671-2022, 2022
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Soil carbon is the Earth’s largest terrestrial carbon store, and the response to climate change represents one of the key uncertainties in obtaining accurate global carbon budgets required to successfully militate against climate change. The ability of climate models to simulate present-day soil carbon is therefore vital. This study assesses soil carbon simulation in the latest ensemble of models which allows key areas for future model development to be identified.
Laurent Bopp, Olivier Aumont, Lester Kwiatkowski, Corentin Clerc, Léonard Dupont, Christian Ethé, Thomas Gorgues, Roland Séférian, and Alessandro Tagliabue
Biogeosciences, 19, 4267–4285, https://doi.org/10.5194/bg-19-4267-2022, https://doi.org/10.5194/bg-19-4267-2022, 2022
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The impact of anthropogenic climate change on the biological production of phytoplankton in the ocean is a cause for concern because its evolution could affect the response of marine ecosystems to climate change. Here, we identify biological N fixation and its response to future climate change as a key process in shaping the future evolution of marine phytoplankton production. Our results show that further study of how this nitrogen fixation responds to environmental change is essential.
Negar Vakilifard, Richard G. Williams, Philip B. Holden, Katherine Turner, Neil R. Edwards, and David J. Beerling
Biogeosciences, 19, 4249–4265, https://doi.org/10.5194/bg-19-4249-2022, https://doi.org/10.5194/bg-19-4249-2022, 2022
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To remain within the Paris climate agreement, there is an increasing need to develop and implement carbon capture and sequestration techniques. The global climate benefits of implementing negative emission technologies over the next century are assessed using an Earth system model covering a wide range of plausible climate states. In some model realisations, there is continued warming after emissions cease. This continued warming is avoided if negative emissions are incorporated.
Marco Reale, Gianpiero Cossarini, Paolo Lazzari, Tomas Lovato, Giorgio Bolzon, Simona Masina, Cosimo Solidoro, and Stefano Salon
Biogeosciences, 19, 4035–4065, https://doi.org/10.5194/bg-19-4035-2022, https://doi.org/10.5194/bg-19-4035-2022, 2022
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Future projections under the RCP8.5 and RCP4.5 emission scenarios of the Mediterranean Sea biogeochemistry at the end of the 21st century show different levels of decline in nutrients, oxygen and biomasses and an acidification of the water column. The signal intensity is stronger under RCP8.5 and in the eastern Mediterranean. Under RCP4.5, after the second half of the 21st century, biogeochemical variables show a recovery of the values observed at the beginning of the investigated period.
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.
Taraka Davies-Barnard, Sönke Zaehle, and Pierre Friedlingstein
Biogeosciences, 19, 3491–3503, https://doi.org/10.5194/bg-19-3491-2022, https://doi.org/10.5194/bg-19-3491-2022, 2022
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Biological nitrogen fixation is the largest natural input of new nitrogen onto land. Earth system models mainly represent global total terrestrial biological nitrogen fixation within observational uncertainties but overestimate tropical fixation. The model range of increase in biological nitrogen fixation in the SSP3-7.0 scenario is 3 % to 87 %. While biological nitrogen fixation is a key source of new nitrogen, its predictive power for net primary productivity in models is limited.
Niel Verbrigghe, Niki I. W. Leblans, Bjarni D. Sigurdsson, Sara Vicca, Chao Fang, Lucia Fuchslueger, Jennifer L. Soong, James T. Weedon, Christopher Poeplau, Cristina Ariza-Carricondo, Michael Bahn, Bertrand Guenet, Per Gundersen, Gunnhildur E. Gunnarsdóttir, Thomas Kätterer, Zhanfeng Liu, Marja Maljanen, Sara Marañón-Jiménez, Kathiravan Meeran, Edda S. Oddsdóttir, Ivika Ostonen, Josep Peñuelas, Andreas Richter, Jordi Sardans, Páll Sigurðsson, Margaret S. Torn, Peter M. Van Bodegom, Erik Verbruggen, Tom W. N. Walker, Håkan Wallander, and Ivan A. Janssens
Biogeosciences, 19, 3381–3393, https://doi.org/10.5194/bg-19-3381-2022, https://doi.org/10.5194/bg-19-3381-2022, 2022
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In subarctic grassland on a geothermal warming gradient, we found large reductions in topsoil carbon stocks, with carbon stocks linearly declining with warming intensity. Most importantly, however, we observed that soil carbon stocks stabilised within 5 years of warming and remained unaffected by warming thereafter, even after > 50 years of warming. Moreover, in contrast to the large topsoil carbon losses, subsoil carbon stocks remained unaffected after > 50 years of soil warming.
Roberto Pilli, Ramdane Alkama, Alessandro Cescatti, Werner A. Kurz, and Giacomo Grassi
Biogeosciences, 19, 3263–3284, https://doi.org/10.5194/bg-19-3263-2022, https://doi.org/10.5194/bg-19-3263-2022, 2022
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To become carbon neutral by 2050, the European Union (EU27) forest C sink should increase to −450 Mt CO2 yr-1. Our study highlights that under current management practices (i.e. excluding any policy scenario) the forest C sink of the EU27 member states and the UK may decrease to about −250 Mt CO2eq yr-1 in 2050. The expected impacts of future climate change, however, add a considerable uncertainty, potentially nearly doubling or halving the sink associated with forest management.
Cited articles
Arístegui, J., Tett, P., Hernández-Guerra, A., Basterretxea, G., Montero, M. F., Wild, K., Sangrá, P., Hernández-Leon, S., Canton, M., García-Braun, J. A., Pacheco, M., and Barton, E. D.: The influence of island-generated eddies on chlorophyll distribution: a study of mesoscale variation around Gran Canaria, Deep-Sea Res. Pt. I, 44, 71–96, https://doi.org/10.1016/S0967-0637(96)00093-3, 1997.
Armstrong, R. A., Lee, C., Hedges, J. I., Honjo, S., and Wakeham, S. G.: A new, mechanistic model for organic carbon fluxes in the ocean based on the quantitative association of POC with ballast minerals, Deep-Sea Res. Pt. II, 49, 219–236, https://doi.org/10.1016/S0967-0645(01)00101-1, 2001.
Bach, L. T.: Reconsidering the role of carbonate ion concentration in calcification by marine organisms, Biogeosciences, 12, 4939–4951, https://doi.org/10.5194/bg-12-4939-2015, 2015.
Bach, L. T., Riebesell, U., Sett, S., Febiri, S., Rzepka, P., and Schulz, K. G.: An approach for particle sinking velocity measurements in the 3–400 µm size range and considerations on the effect of temperature on sinking rates, Mar. Biol., 159, 1853–1864, https://doi.org/10.1007/s00227-012-1945-2, 2012.
Bach, L. T., Boxhammer, T., Larsen, A., Hildebrandt, N., Schulz, K. G., and Riebesell, U.: Influence of plankton community structure on the sinking velocity of marine aggregates, Global Biogeochem. Cy., 30, 1145–1165, https://doi.org/10.1029/2019GB006256, 2016.
Bach, L. T., Alvarez-Fernandez, S., Hornick, T., Stuhr, A., and Riebesell, U.: Simulated ocean acidification reveals winners and losers in coastal phytoplankton, PLOS ONE 12, e0188198, https://doi.org/10.1371/journal.pone.0188198, 2017.
Bach, L. T., Gill, S. J., Rickaby, R. E. M., Gore, S., and Renforth, P.: CO2 Removal With Enhanced Weathering and Ocean Alkalinity Enhancement, Frontiers in Climate, 1, 7, https://doi.org/10.3389/fclim.2019.00007, 2019a.
Bach, L. T., Hernández-Hernández, N., Taucher, J., Spisla, C., Sforna, C., Riebesell, U., and Arístegui, J.: Effects of Elevated CO2 on a Natural Diatom Community in the Subtropical NE Atlantic, Front. Mar. Sci., 6, 320, https://doi.org/10.3389/fmars.2019.00075, 2019b.
Bach, L. T., Stange, P., Taucher, J., Achterberg, E. P., Algueró-Muñiz, M., Horn, H., Esposito, M., and Riebesell, U.: The Influence of Plankton Community Structure on Sinking Velocity and Remineralization Rate of Marine Aggregates, Global Biogeochem. Cy., 33, 971–994, https://doi.org/10.1029/2019GB006256, 2019c.
Bach, L. T., Paul, A. J., Boxhammer, T., von der Esch, E., Graco, M., Schulz, K. G., Achterberg, E., Aguayo, P., Arístegui, J., Ayón, P., Baños, I., Bernales, A., Boegeholz, A. S., Chavez, F., Chavez, G., Chen, S.-M., Doering, K., Filella, A., Fischer, M., Grasse, P., Haunost, M., Hennke, J., Hernández-Hernández, N., Hopwood, M., Igarza, M., Kalter, V., Kittu, L., Kohnert, P., Ledesma, J., Lieberum, C., Lischka, S., Löscher, C., Ludwig, A., Mendoza, U., Meyer, J., Meyer, J., Minutolo, F., Ortiz Cortes, J., Piiparinen, J., Sforna, C., Spilling, K., Sanchez, S., Spisla, C., Sswat, M., Zavala Moreira, M., and Riebesell, U.: Factors controlling plankton community production, export flux, and particulate matter stoichiometry in the coastal upwelling system off Peru, Biogeosciences, 17, 4831–4852, https://doi.org/10.5194/bg-17-4831-2020, 2020.
Barton, E. D., Arìstegui, J., Tett, P., Cantón, M., Garcìa-Braun, J., Hernández-León, S., Nykjaer, L., Almeida, C., Almunia, J., Ballesteros, S., Basterretxea, G., Escánez, J., Garcìa-Weill, L., Hernández-Guerra, A., López-Laatzen, F., Molina, R., Montero, M. F., Navarro-Pérez, E., Rodrìguez, J. M., van Lenning, K., Vélez, H., and Wild, K.: The transition zone of the Canary Current upwelling region, Prog. Oceanogr., 41, 455–504, https://doi.org/10.1016/S0079-6611(98)00023-8, 1998.
Basterretxea, G., Barton, E. D., Tett, P., Sangrá, P., Navarro-Perez, E., and Arı́stegui, J.: Eddy and deep chlorophyl maximum response to wind-shear in the lee of Gran Canaria, Deep-Sea Res. Pt. I, 49, 1087–1101, https://doi.org/10.1016/S0967-0637(02)00009-2, 2002.
Baumann, M., Taucher, J., Paul, A. J., Heinemann, M., Vanharanta, M., Bach, L. T., Spilling, K., Ortiz, J., Arístegui, J., Hernández-Hernández, N., Baños, I., and Riebesell, U.: Effect of Intensity and Mode of Artificial Upwelling on Particle Flux and Carbon Export, Frontiers in Marine Science, 8, 742142, https://doi.org/10.3389/fmars.2021.742142, 2021.
Beman, J. M., Chow, C.-E., King, A. L., Feng, Y., Fuhrman, J. A., Andersson, A., Bates, N. R., Popp, B. N., and Hutchins, D. A.: Global declines in oceanic nitrification rates as a consequence of ocean acidification, P. Natl. Acad. Sci. USA, 108, 208–213, https://doi.org/10.1073/pnas.1011053108, 2011.
Böckmann, S., Koch, F., Meyer, B., Pausch, F., Iversen, M., Driscoll, R., Laglera, L. M., Hassler, C., and Trimborn, S.: Salp fecal pellets release more bioavailable iron to Southern Ocean phytoplankton than krill fecal pellets, Curr. Biol., 31, P2737–2746.E3, https://doi.org/10.1016/j.cub.2021.02.033, 2021.
Bopp, L., Resplandy, L., Orr, J. C., Doney, S. C., Dunne, J. P., Gehlen, M., Halloran, P., Heinze, C., Ilyina, T., Séférian, R., Tjiputra, J., and Vichi, M.: Multiple stressors of ocean ecosystems in the 21st century: projections with CMIP5 models, Biogeosciences, 10, 6225–6245, https://doi.org/10.5194/bg-10-6225-2013, 2013.
Boxhammer, T., Bach, L. T., Czerny, J., and Riebesell, U.: Technical note: Sampling and processing of mesocosm sediment trap material for quantitative biogeochemical analysis, Biogeosciences, 13, 2849–2858, https://doi.org/10.5194/bg-13-2849-2016, 2016.
Boyd, P. W., Sherry, N. D., Berges, J. A., Bishop, J. K. B., Calvert, S. E., Charette, M. A., Giovannoni, S. J., Goldblatt, R., Harrison, P. J., Moran, S. B., Roy, S., Soon, M., Strom, S., Thibault, D., Vergin, K. L., Whitney, F. A., and Wong, C. S.: Transformations of biogenic particulates from the pelagic to the deep ocean realm, Deep-Sea Res. Pt. II, 46, 2761–2792, https://doi.org/10.1016/S0967-0645(99)00083-1, 1999.
Brečević, L. and Nielsen, A. E.: Solubility of amorphous calcium carbonate, J. Cryst. Growth, 98, 504–510, https://doi.org/10.1016/0022-0248(89)90168-1, 1989.
Byrne, C. D., Law, R. J., Hudson, P. M., Thain, J. E., and Fileman, T. W.: Measurements of the dispersion of liquid industrial waste discharged into the wake of a dumping vessel, Water Res., 22, 1577–1584, https://doi.org/10.1016/0043-1354(88)90171-6, 1988.
Cabanes, D. J. E., Norman, L., Santos-Echeandía, J., Iversen, M. H., Trimborn, S., Laglera, L. M., and Hassler, C. S.: First Evaluation of the Role of Salp Fecal Pellets on Iron Biogeochemistry, Front Mar. Sci., 3, 289, https://doi.org/10.3389/fmars.2016.00289, 2017.
Cherabier, P. and Ferrière, R.: Eco-evolutionary responses of the microbial loop to surface ocean warming and consequences for primary production, ISME J., 16, 1130–1139, https://doi.org/10.1038/s41396-021-01166-8, 2022.
Ciais, P., Sabine, C., Bala, G., Bopp, L., Brovkin, V., Canadell, J., Chhabra, A., DeFries, R., Galloway, J., and Heimann, M.: Carbon and Other Biogeochemical Cycles, in: Climate Change 2013 – The Physical Science Basis: Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Change, I. P. on C., Cambridge University Press, Cambridge, 465–570, https://doi.org/10.1017/CBO9781107415324.015, 2014.
Coverly, S., Kérouel, R., and Aminot, A.: A re-examination of matrix effects in the segmented-flow analysis of nutrients in sea and estuarine water, Anal. Chim. Acta, 712, 94–100, https://doi.org/10.1016/j.aca.2011.11.008, 2012.
Dai, M., Luo, Y., Achterberg, E. P., Browning, T. J., Cai, Y., Cao, Z., Chai, F., Chen, B., Church, M. J., Ci, D., Du, C., Gao, K., Guo, X., Hu, Z., Kao, S., Laws, E. A., Lee, Z., Lin, H., Liu, Q., Liu, X., Luo, W., Meng, F., Shang, S., Shi, D., Saito, H., Song, L., Wan, X. S., Wang, Y., Wang, W., Wen, Z., Xiu, P., Zhang, J., Zhang, R., and Zhou, K.: Upper Ocean Biogeochemistry of the Oligotrophic North Pacific Subtropical Gyre: From Nutrient Sources to Carbon Export, Rev. Geophys., 61, e2022RG000800, https://doi.org/10.1029/2022RG000800, 2023.
Dickson, A.: Standards for Ocean Measurements, Oceanography, 23, 34–47, https://doi.org/10.5670/oceanog.2010.22, 2010.
Doney, S. C., Fabry, V. J., Feely, R. A., and Kleypas, J. A.: Ocean Acidification, Annu. Rev. Mar. Sci., 1, 169–192, https://doi.org/10.1146/annurev.marine.010908.163834, 2009.
Endres, S., Galgani, L., Riebesell, U., Schulz, K.-G., and Engel, A.: Stimulated Bacterial Growth under Elevated pCO2: Results from an Off-Shore Mesocosm Study, PLoS One, 9, e99228, https://doi.org/10.1371/journal.pone.0099228, 2014.
Engel, A., Abramson, L., Szlosek, J., Liu, Z., Stewart, G., Hirschberg, D., and Lee, C.: Investigating the effect of ballasting by CaCO3 in Emiliania huxleyi, II, Deep-Sea Res. Pt. II, 56, 1408–1419, https://doi.org/10.1016/j.dsr2.2008.11.028, 2009.
Feng, E. Y., Koeve, W., Keller, D. P., and Oschlies, A.: Model-Based Assessment of the CO2 Sequestration Potential of Coastal Ocean Alkalinization, Earth's Future, 5, 1252–1266, https://doi.org/10.1002/2017EF000659, 2017.
Ferderer, A., Chase, Z., Kennedy, F., Schulz, K. G., and Bach, L. T.: Assessing the influence of ocean alkalinity enhancement on a coastal phytoplankton community, Biogeosciences, 19, 5375–5399, https://doi.org/10.5194/bg-19-5375-2022, 2022.
Francois, R., Honjo, S., Krishfield, R., and Manganini, S.: Factors controlling the flux of organic carbon to the bathypelagic zone of the ocean, Global Biogeochem. Cy., 16, 34-1–34-20, https://doi.org/10.1029/2001GB001722, 2002.
Freudenthal, T., Neuer, S., Meggers, H., Davenport, R., and Wefer, G.: Influence of lateral particle advection and organic matter degradation on sediment accumulation and stable nitrogen isotope ratios along a productivity gradient in the Canary Islands region, Mar. Geol., 177, 93–109, https://doi.org/10.1016/S0025-3227(01)00126-8, 2001.
Fumasoli, A., Bürgmann, H., Weissbrodt, D. G., Wells, G. F., Beck, K., Mohn, J., Morgenroth, E., and Udert, K. M.: Growth of Nitrosococcus-Related Ammonia Oxidizing Bacteria Coincides with Extremely Low pH Values in Wastewater with High Ammonia Content, Environ. Sci. Technol., 51, 6857–6866, https://doi.org/10.1021/acs.est.7b00392, 2017.
Gately, J. A., Kim, S. M., Jin, B., Brzezinski, M. A., and Iglesias-Rodriguez, M. D.: Coccolithophores and diatoms resilient to ocean alkalinity enhancement: A glimpse of hope?, Sci. Adv., 9, eadg6066, https://doi.org/10.1126/sciadv.adg6066, 2023.
Gattuso, J.-P., Magnan, A., Billé, R., Cheung, W. W. L., Howes, E. L., Joos, F., Allemand, D., Bopp, L., Cooley, S. R., Eakin, C. M., Hoegh-Guldberg, O., Kelly, R. P., Pörtner, H.-O., Rogers, A. D., Baxter, J. M., Laffoley, D., Osborn, D., Rankovic, A., Rochette, J., Sumaila, U. R., Treyer, S., and Turley, C.: Contrasting futures for ocean and society from different anthropogenic CO2 emissions scenarios, Science, 349, aac4722, https://doi.org/10.1126/science.aac4722, 2015.
GESAMP: High level review of a wide range of proposed marine geoengineering techniques, 98th ed., edited by: GESAMP, International Maritime Organization, London, https://doi.org/10.25607/OBP-1944, 2019.
González, M. F. and Ilyina, T.: Impacts of artificial ocean alkalinization on the carbon cycle and climate in Earth system simulations, Geophys. Res. Lett., 43, 6493–6502, https://doi.org/10.1002/2016GL068576, 2016.
Griffioen, J.: Enhanced weathering of olivine in seawater: the efficiency as revealed by thermodynamic scenario analysis, Sci. Total Environ., 575, 536–544, https://doi.org/10.1016/j.scitotenv.2016.09.008, 2017.
Guidi, L., Legendre, L., Reygondeau, G., Uitz, J., Stemmann, L., and Henson, S. A.: A new look at ocean carbon remineralization for estimating deepwater sequestration, Global Biogeochem. Cy., 29, 1044–1059, https://doi.org/10.1002/2014GB005063, 2015.
Hansen, H. P. and Koroleff, F.: Determination of nutrients, in: Methods of Seawater Analysis, 159–228, https://doi.org/10.1002/9783527613984.ch10, 1999.
Hartmann, J., West, A. J., Renforth, P., Köhler, P., La Rocha, C. L., Wolf-Gladrow, D. A., Dürr, H. H., and Scheffran, J.: Enhanced chemical weathering as a geoengineering strategy to reduce atmospheric carbon dioxide, supply nutrients, and mitigate ocean acidification, Rev. Geophys., 51, 113–149, https://doi.org/10.1002/rog.20004, 2013.
Hartmann, J., Suitner, N., Lim, C., Schneider, J., Marín-Samper, L., Arístegui, J., Renforth, P., Taucher, J., and Riebesell, U.: Stability of alkalinity in ocean alkalinity enhancement (OAE) approaches – consequences for durability of CO2 storage, Biogeosciences, 20, 781–802, https://doi.org/10.5194/bg-20-781-2023, 2023.
Hessen, D. O., Ågren, G. I., Anderson, T. R., Elser, J. J., and De Ruiter, P. C.: Carbon sequestration in ecosystems: the role of stoichiometry, Ecology, 85, 1179–1192, https://doi.org/10.1890/02-0251, 2004.
Honjo, S., Manganini, S. J., Krishfield, R. A., and Francois, R.: Particulate organic carbon fluxes to the ocean interior and factors controlling the biological pump, Prog. Oceanogr., 76, 217–285, https://doi.org/10.1016/j.pocean.2007.11.003, 2008.
Iversen, M. H.: Carbon Export in the Ocean: A Biologist's Perspective, Ann. Rev. Mar. Sci., 15, 357–381, https://doi.org/10.1146/annurev-marine-032122-035153, 2023.
Iversen, M. H. and Ploug, H.: Temperature effects on carbon-specific respiration rate and sinking velocity of diatom aggregates – potential implications for deep ocean export processes, Biogeosciences, 10, 4073–4085, https://doi.org/10.5194/bg-10-4073-2013, 2013.
Jokiel, P. L.: The reef coral two compartment proton flux model, J Exp Mar. Biol. Ecol, 409, 1–12, https://doi.org/10.1016/j.jembe.2011.10.008, 2011.
Jordan, R. W.: Coccolithophores, in: Encyclopedia of Microbiology (Third Edition), edited by: Schaechter, M., Academic Press, Oxford, 593–605, https://doi.org/10.1016/B978-012373944-5.00249-2, 2009.
Karthäuser, C., Ahmerkamp, S., Marchant, H. K., Bristow, L. A., Hauss, H., Iversen, M. H., Kiko, R., Maerz, J., Lavik, G., and Kuypers, M. M. M.: Small sinking particles control anammox rates in the Peruvian oxygen minimum zone, Nat. Commun., 12, 3235, https://doi.org/10.1038/s41467-021-23340-4, 2021.
Kheshgi, H. S.: Sequestering atmospheric carbon dioxide by increasing ocean alkalinity, Energy, 20, 915–922, https://doi.org/10.1016/0360-5442(95)00035-F, 1995.
Klaas, C. and Archer, D. E.: Association of sinking organic matter with various types of mineral ballast in the deep sea, Global Biogeochem. Cy., 16, 63-1–63-14, https://doi.org/10.1029/2001GB001765, 2002.
Koeve, W.: Upper ocean carbon fluxes in the Atlantic Ocean, Global Biogeochem. Cy., 16, 4-1–4-17, https://doi.org/10.1029/2001GB001836, 2002.
Köhler, P., Hartmann, J., and Wolf-Gladrow, D. A.: Geoengineering potential of artificially enhanced silicate weathering of olivine, P. Natl. Acad. Sci. USA, 107, 20228–20233, https://doi.org/10.1073/pnas.1000545107, 2010.
Kwon, E. Y., Primeau, F., and Sarmiento, J. L.: The impact of remineralization depth on the air–sea carbon balance, Nat. Geosci., 2, 630–635, https://doi.org/10.1038/ngeo612, 2009.
Le Moigne, F. A. C., Henson, S. A., Cavan, E., Georges, C., Pabortsava, K., Achterberg, E. P., Ceballos-Romero, E., Zubkov, M., and Sanders, R. J.: What causes the inverse relationship between primary production and export efficiency in the Southern Ocean?, Geophys. Res. Lett., 43, 4457–4466, https://doi.org/10.1002/2016GL068480, 2016.
Li, C., Luo, X., Huang, X., and Gu, B.: Effects of Temperature, Salinity, pH, and Light on Filtering and Grazing Rates of a Calanoid Copepod (Schmackeria dubia), Sci. World J., 8, 838071, https://doi.org/10.1100/tsw.2008.153, 2008.
Lüdecke, D., Ben-Shachar, M., Patil, I., Waggoner, P., and Makowski, D.: performance, J. Open Source Softw., 6, 3139, https://doi.org/10.21105/joss.03139, 2021.
Lueker, T. J., Dickson, A. G., and Keeling, C. D.: Ocean pCO2 calculated from dissolved inorganic carbon, alkalinity, and equations for K1 and K2, Mar. Chem., 70, 105–119, https://doi.org/10.1016/S0304-4203(00)00022-0, 2000.
Marion, G. M., Millero, F. J., and Feistel, R.: Precipitation of solid phase calcium carbonates and their effect on application of seawater SA–T–P models, Ocean Sci., 5, 285–291, https://doi.org/10.5194/os-5-285-2009, 2009.
Martínez-García, A., Sigman, D. M., Ren, H., Anderson, R. F., Straub, M., Hodell, D. A., Jaccard, S. L., Eglinton, T. I., and Haug, G. H.: Iron fertilization of the Subantarctic Ocean during the last ice age, Science, 343, 1347–1350, https://doi.org/10.1126/science.1246848, 2014.
Masson-Delmotte, V., Zhai, P., Pörtner, H.-O., Roberts, D., Skea, J., Shukla, P. R., al., et, and IPCC (Eds.): Climate Change 2021: The Physical Science Basis, Cambridge University Press, 2021.
McCave, I. N.: Particulate size spectra, behavior, and origin of nepheloid layers over the Nova Scotian Continental Rise, J. Geophys. Res.-Oceans, 88, 7647–7666, https://doi.org/10.1029/JC088iC12p07647, 1983.
Monteiro, F., Bach, L. T., Brownlee, C., Bown, P., E, R. R., Poulton, A. J., Tyrrell, T., Beaufort, L., Dutkiewicz, S., Gibbs, S., Gutowska, M. A., Lee, R., Riebesell, U., Young, J., and Ridgwell, A.: Why marine phytoplankton calcify, Sci. Adv., 2, e1501822, https://doi.org/10.1126/sciadv.1501822, 2016.
Moras, C. A., Bach, L. T., Cyronak, T., Joannes-Boyau, R., and Schulz, K. G.: Ocean alkalinity enhancement – avoiding runaway CaCO3 precipitation during quick and hydrated lime dissolution, Biogeosciences, 19, 3537–3557, https://doi.org/10.5194/bg-19-3537-2022, 2022.
Morris, A. W. and Riley, J. P.: The determination of nitrate in sea water, Anal. Chim. Acta, 29, 272–279, https://doi.org/10.1016/S0003-2670(00)88614-6, 1963.
Morse, J. W. and He, S.: Influences of T, S and
Mucci, A.: The solubility of calcite and aragonite in seawater at various salinities, temperatures, and one atmosphere total pressure, Am. J. Sci, 283, 780–799, 1983.
Mullin, J. B. and Riley, J. P.: The colorimetric determination of silicate with special reference to sea and natural waters, Anal. Chim. Acta, 12, 162–176, https://doi.org/10.1016/S0003-2670(00)87825-3, 1955.
Murphy, J. and Riley, J. P.: A modified single solution method for the determination of phosphate in natural waters, Anal. Chim. Acta, 27, 31–36, https://doi.org/10.1016/S0003-2670(00)88444-5, 1962.
National Acadmies of Sciences: A Research Strategy for Ocean-based Carbon Dioxide Removal and Sequestration, National Academies Press, Washington, D.C., https://doi.org/10.17226/26278, 2021.
Ortiz, J., Arístegui, J., Taucher, J., and Riebesell, U.: Artificial Upwelling in Singular and Recurring Mode: Consequences for Net Community Production and Metabolic Balance, Frontiers in Marine Science, 8, 743105, https://doi.org/10.3389/fmars.2021.743105, 2022.
Paquay, F. S. and Zeebe, R. E.: Assessing possible consequences of ocean liming on ocean pH, atmospheric CO2 concentration and associated costs, Int. J. Greenh. Gas Con., 17, 183–188, https://doi.org/10.1016/j.ijggc.2013.05.005, 2013.
Passow, U. and Carlson, C. A.: The biological pump in a high CO2 world, Mar. Ecol. Prog. Ser., 470, 249–271, https://doi.org/10.3354/meps09985, 2012.
Paul, A. J., Haunost, M., Goldenberg, S. U., Hartmann, J., Sánchez, N., Schneider, J., Suitner, N., and Riebesell, U.: Ocean alkalinity enhancement in an open ocean ecosystem: Biogeochemical responses and carbon storage durability, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2024-417, 2024.
Pierrot, D. E., Wallace, D. W. R., and Lewis, E.: MS Excel Program Developed for CO2 System Calculations, GitHub [code], https://github.com/dpierrot/co2sys_xl (last access: 14 October 2023), 2011.
Pinheiro, J., Bates, D., and R Core Team: nlme: Linear and Nonlinear Mixed Effects Models, R package version 3.1-160, https://CRAN.R-project.org/package=nlme (last access: 14 October 2023), 2022.
Piontek, J., Lunau, M., Händel, N., Borchard, C., Wurst, M., and Engel, A.: Acidification increases microbial polysaccharide degradation in the ocean, Biogeosciences, 7, 1615–1624, https://doi.org/10.5194/bg-7-1615-2010, 2010.
Ploug, H. and Grossart, H.-P.: Bacterial growth and grazing on diatom aggregates, Limnol. Oceanogr., 45, 1467–1475, https://doi.org/10.4319/lo.2000.45.7.1467, 2000.
Pommerening-Röser, A. and Koops, H. P.: Environmental pH as an important factor for the distribution of urease positive ammonia-oxidizing bacteria, Microbiol. Res., 160, 27–35, https://doi.org/10.1016/j.micres.2004.09.006, 2005.
Puig, P., Madron, X. D. de, Salat, J., Schroeder, K., Martín, J., Karageorgis, A. P., Palanques, A., Roullier, F., Lopez-Jurado, J. L., Emelianov, M., Moutin, T., and Houpert, L.: Thick bottom nepheloid layers in the western Mediterranean generated by deep dense shelf water cascading, Prog. Oceanogr., 111, 1–23, https://doi.org/10.1016/j.pocean.2012.10.003, 2013.
R Core Team: R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria, https://www.R-project.org/ (last access: 14 October 2023), 2021.
Renforth, P. and Henderson, G.: Assessing ocean alkalinity for carbon sequestration, Rev. Geophys., 55, 636–674, https://doi.org/10.1002/2016RG000533, 2017.
Riebesell, U., Wolf-Gladrow, D. A., and Smetacek, V.: Carbon dioxide limitation of marine phytoplankton growth rates, Nature, 361, 249–251, https://doi.org/10.1038/361249a0, 1993.
Riebesell, U., Czerny, J., von Bröckel, K., Boxhammer, T., Büdenbender, J., Deckelnick, M., Fischer, M., Hoffmann, D., Krug, S. A., Lentz, U., Ludwig, A., Muche, R., and Schulz, K. G.: Technical Note: A mobile sea-going mesocosm system – new opportunities for ocean change research, Biogeosciences, 10, 1835–1847, https://doi.org/10.5194/bg-10-1835-2013, 2013.
Riebesell, U., Bach, L. T., Bellerby, R. G. J., Monsalve, J., Boxhammer, T., Czerny, J., Larsen, A., Ludwig, A., and Schulz, K. G.: Competitive fitness of a predominant pelagic calcifier impaired by ocean acidification, Nat. Geosci., 10, 19–23, https://doi.org/10.1038/ngeo2854, 2017.
Ristow, G. H.: Wall correction factor for sinking cylinders in fluids, Phys. Rev. E, 55, 2808–2813, https://doi.org/10.1103/PhysRevE.55.2808, 1997.
Rothwell, R. G.: Sedimentary Rocks, in: Reference Module in Earth Systems and Environmental Sciences, Elsevier, https://doi.org/10.1016/B978-0-12-409548-9.10493-2, 2016.
Salter, I., Schiebel, R., Ziveri, P., Movellan, A., Lampitt, R., and Wolff, G. A.: Carbonate counter pump stimulated by natural iron fertilization in the Polar Frontal Zone, Nat. Geosci., 7, 885–889, https://doi.org/10.1038/ngeo2285, 2014.
Sarthou, G., Vincent, D., Christaki, U., Obernosterer, I., Timmermans, K. R., and Brussaard, C. P. D.: The fate of biogenic iron during a phytoplankton bloom induced by natural fertilisation: Impact of copepod grazing, Deep-Sea Res. Pt. II, 55, 734–751, https://doi.org/10.1016/j.dsr2.2007.12.033, 2008.
Schmittner, A., Oschlies, A., Schulz, K. G., and Riebesell, U.: Simulated 21st century's increase in oceanic suboxia by CO2-enhanced biotic carbon export, Global Biogeochem. Cy., 22, GB4008, https://doi.org/10.1029/2007GB003147, 2008.
Schneider, B., Schlitzer, R., Fischer, G., and Nöthig, E.-M.: Depth-dependent elemental compositions of particulate organic matter (POM) in the ocean, Global Biogeochem. Cy., 17, 1032, https://doi.org/10.1029/2002GB001871, 2003.
Shaffer, G.: Biogeochemical cycling in the global ocean, J. Geophys. Res.-Oceans, 101, 3723–3745, https://doi.org/10.1029/95JC03373, 1996.
Sharp, J. H.: Improved analysis for “particulate” organic carbon and nitrogen from seawater, Limnol. Oceanogr., 19, 984–989, https://doi.org/10.4319/lo.1974.19.6.0984, 1974.
Smith, P., Davis, S. J., Creutzig, F., Fuss, S., Minx, J., Gabrielle, B., Kato, E., Jackson, R. B., Cowie, A., and Kriegler, E.: Biophysical and economic limits to negative CO2 emissions, Nat. Clim. Change, 6, 42–50, https://doi.org/10.1038/nclimate2870, 2016.
Sprengel, C., Baumann, K. H., Henderiks, J., Henrich, R., and Neuer, S.: Modern coccolithophore and carbonate sedimentation along a productivity gradient in the Canary Islands region: seasonal export production and surface accumulation rates, Deep-Sea Res. Pt. II, 49, 3577–3598, https://doi.org/10.1016/S0967-0645(02)00099-1, 2002.
Stange, P., Taucher, J., Bach, L. T., Algueró-Muñiz, M., Horn, H. G., Krebs, L., Boxhammer, T., Nauendorf, A. K., and Riebesell, U.: Ocean Acidification-Induced Restructuring of the Plankton Food Web Can Influence the Degradation of Sinking Particles, Front. Mar. Sci., 5, 140, https://doi.org/10.3389/fmars.2018.00140, 2018.
Strickland, J. D. H. and Parsons, T. R.: A Practical Handbook of Seawater Analysis, 2nd edn., Ottawa, Canada, Fisheries Research Board of Canada, 310 pp., Bulletin Fisheries Research Board of Canada, 167, https://doi.org/10.25607/OBP-1791, 1972.
Stukel, M. R., Landry, M. R., Benitez-Nelson, C. R., and Goericke, R.: Trophic cycling and carbon export relationships in the California Current Ecosystem, Limnol. Oceanogr., 56, 1866–1878, https://doi.org/10.4319/lo.2011.56.5.1866, 2011.
Subhas, A. V, Marx, L., Reynolds, S., Flohr, A., Mawji, E. W., Brown, P. J., and Cael, B. B.: Microbial ecosystem responses to alkalinity enhancement in the North Atlantic Subtropical Gyre, Frontiers in Climate, 4, 784997, https://doi.org/10.3389/fclim.2022.784997, 2022.
Suessle, P., Taucher, J., Goldenberg, S. U., Baumann, M., Noche-Ferreira, A., and Vanharanta, M.: KOSMOS 2021 Gran Canaria mesocosm study on ocean alkalinity enhancement: sediment trap particle flux data and water column biogeochemistry, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.967359, 2024.
Suzuki, S., Kawachi, M., Tsukakoshi, C., Nakamura, A., Hagino, K., Inouye, I., and Ishida, K.: Unstable Relationship Between Braarudosphaera bigelowii (= Chrysochromulina parkeae) and Its Nitrogen-Fixing Endosymbiont, Front. Plant. Sci., 12, 74989, https://doi.org/10.3389/fpls.2021.749895, 2021.
Taucher, J. and Oschlies, A.: Can we predict the direction of marine primary production change under global warming?, Geophys. Res. Lett., 38, LO2603, https://doi.org/10.1029/2010GL045934, 2011.
Taucher, J., Bach, L. T., Boxhammer, T., Nauendorf, A., Consortium, T. G. C. K., Achterberg, E. P., Algueró-Muñiz, M., Arístegui, J., Czerny, J., Esposito, M., Guan, W., Haunost, M., Horn, H. G., Ludwig, A., Meyer, J., Spisla, C., Sswat, M., Stange, P., and Riebesell, U.: Influence of Ocean Acidification and Deep Water Upwelling on Oligotrophic Plankton Communities in the Subtropical North Atlantic, Front. Mar. Sci., 4, 85, https://doi.org/10.3389/fmars.2017.00085, 2017.
Taucher, J., Boxhammer, T., Bach, L. T., Paul, A. J., Schartau, M., Stange, P., and Riebesell, U.: Changing carbon-to-nitrogen ratios of organic-matter export under ocean acidification, Nat. Clim. Change, 11, 52–57, https://doi.org/10.1038/s41558-020-00915-5, 2021.
Taylor, L. L., Quirk, J., Thorley, R. M. S., Kharecha, P. A., Hansen, J., Ridgwell, A., Lomas, M. R., Banwart, S. A., and Beerling, D. J.: Enhanced weathering strategies for stabilizing climate and averting ocean acidification, Nat. Clim. Change, 6, 402–406, https://doi.org/10.1038/nclimate2882, 2016.
Utermöhl, H.: Zur Vervollkommnung der quantitativen Phytoplankton Methodik, in: Mitteilungen der IVL, Number 9, Schweizerbart Science Publishers, Stuttgart, Germany, ISBN 9783510520091, 1958.
Webb, A. L., Malin, G., Hopkins, F. E., Ho, K. L., Riebesell, U., Schulz, K., Larsen, A., and Liss, P.: Ocean acidification affects production of DMS and DMSP measured in a mesocosm study and cultures of Emiliania huxleyi and a mesocosm study, Environ. Chem., 13, 314–329, https://doi.org/10.1071/EN14268, 2016.
Welschmeyer, N. A.: Fluorometric analysis of chlorophyll a in the presence of chlorophyll b and pheopigments, Limnol. Oceanogr., 39, 1985–1992, https://doi.org/10.4319/lo.1994.39.8.1985, 1994.
Wickham, H., Averick, M., Bryan, J., Chang, W., McGowan, L., François, R., Grolemund, G., Hayes, A., Henry, L., Hester, J., Kuhn, M., Pedersen, T., Miller, E., Bache, S., Müller, K., Ooms, J., Robinson, D., Seidel, D., Spinu, V., Takahashi, K., Vaughan, D., Wilke, C., Woo, K., and Yutani, H.: Welcome to the Tidyverse, J. Open Source Softw., 4, 1686, https://doi.org/10.21105/joss.01686, 2019.
Wurgaft, E., Wang, Z. A., Churchill, J. H., Dellapenna, T., Song, S., Du, J., Ringham, M. C., Rivlin, T., and Lazar, B.: Particle Triggered Reactions as an Important Mechanism of Alkalinity and Inorganic Carbon Removal in River Plumes, Geophys. Res. Lett., 48, e2021GL093178, https://doi.org/10.1029/2021GL093178, 2021.
Xin, X., Goldenberg, S., Taucher, J., Stuhr, A., Aristegui, J., and Riebesell, U.: Resilience of phytoplankton and microzooplankton communities under ocean alkalinity enhancement in the oligotrophic ocean, Environ. Sci. Technol., 58, 20918–20930, https://doi.org/10.1021/acs.est.4c09838, 2025.
Zagarese, H. E., Sagrario, M. de los Á. G., Wolf-Gladrow, D., Nõges, P., Nõges, T., Kangur, K., Matsuzaki, S.-I. S., Kohzu, A., Vanni, M. J., Özkundakci, D., Echaniz, S. A., Vignatti, A., Grosman, F., Sanzano, P., Van Dam, B., and Knoll, L. B.: Patterns of CO2 concentration and inorganic carbon limitation of phytoplankton biomass in agriculturally eutrophic lakes, Water Res., 190, 116715, https://doi.org/10.1016/j.watres.2020.116715, 2021.
Zeebe, R. E. and Wolf-Gladrow, D. A.: CO2 in seawater: Equilibrium, kinetics, isotopes, edited by: Zeebe, R. E. and Wolf-Gladrow, D. A., Elsevier, Amsterdam, New York, 346 pp., ISBN 9780444509468, 2010.
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This paper examines the effects of ocean alkalinity enhancement (OAE) on a key biogeochemical process: the biological carbon pump. The findings suggest that, under the conditions studied, the biological pump will largely remain unaffected by OAE. Gaining insights into how such interventions influence complex oceanographic processes at the ecosystem level is essential for assessing both the efficacy and safety of OAE.
This paper examines the effects of ocean alkalinity enhancement (OAE) on a key biogeochemical...
Short summary
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.
Ocean alkalinity enhancement (OAE) is a negative emission technology which may alter marine...
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