Articles | Volume 12, issue 19
https://doi.org/10.5194/bg-12-5647-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-12-5647-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
07 Oct 2015
Research article |
| 07 Oct 2015
Effects of varied nitrate and phosphate supply on polysaccharidic and proteinaceous gel particle production during tropical phytoplankton bloom experiments
GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
C. Borchard
GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
A. Loginova
GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
J. Meyer
GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
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High primary production in the Peruvian upwelling system is followed by rapid heterotrophic utilization of organic matter and supports the formation of one of the most intense oxygen minimum zones (OMZs) in the world. Here, we estimated vertical fluxes of oxygen and dissolved organic matter (DOM) from the surface to the OMZ. Our results suggest that DOM remineralization substantially reduces oxygen concentration in the upper water column and controls the shape of the upper oxycline.
Soeren Thomsen, Johannes Karstensen, Rainer Kiko, Gerd Krahmann, Marcus Dengler, and Anja Engel
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Physical and biogeochemical observations from an autonomous underwater vehicle in combination with ship-based measurements are used to investigate remote and local drivers of the oxygen and nutrient variability off Mauritania. Beside the transport of oxygen and nutrients characteristics from remote areas towards Mauritania also local remineralization of organic material close to the seabed seems to be important for the distribution of oxygen and nutrients.
Carolina Cisternas-Novoa, Frédéric A. C. Le Moigne, and Anja Engel
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We investigate the composition and vertical fluxes of POM in two deep basins of the Baltic Sea (GB: Gotland Basin and LD: Landsort Deep). The two basins showed different O2 regimes resulting from the intrusion of oxygen-rich water from the North Sea that ventilated the deep waters in GB, but not in LD.
In GB, O2 intrusions lead to a high abundance of manganese oxides that aggregate with POM, altering its composition and vertical flux and contributing to a higher POC transfer efficiency in GB.
Cui-Ci Sun, Martin Sperling, and Anja Engel
Biogeosciences, 15, 3577–3589, https://doi.org/10.5194/bg-15-3577-2018, https://doi.org/10.5194/bg-15-3577-2018, 2018
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Biogenic gel particles such as transparent exopolymer particles (TEP) and Coomassie stainable particles (CSP) are important components in the sea-surface microlayer (SML). Their potential role in air–sea gas exchange and in primary organic aerosol emission has generated considerable research interest. Our wind wave channel experiment revealed how wind speed controls the accumulation and size distribution of biogenic gel particles in the SML.
Anja Engel, Hannes Wagner, Frédéric A. C. Le Moigne, and Samuel T. Wilson
Biogeosciences, 14, 1825–1838, https://doi.org/10.5194/bg-14-1825-2017, https://doi.org/10.5194/bg-14-1825-2017, 2017
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To better understand the role of oxygen for the biological carbon pump, we studied particle fluxes through hypoxic waters in the eastern tropical North Atlantic. Attenuation of organic carbon fluxes over depth was lower than expected from seawater temperatures, indicating co-effects of oxygen concentration. Differences were observed for individual organic components, suggesting that future carbon export fluxes may depend on changes in surface ocean organic matter quality under global change.
Helmke Hepach, Birgit Quack, Susann Tegtmeier, Anja Engel, Astrid Bracher, Steffen Fuhlbrügge, Luisa Galgani, Elliot L. Atlas, Johannes Lampel, Udo Frieß, and Kirstin Krüger
Atmos. Chem. Phys., 16, 12219–12237, https://doi.org/10.5194/acp-16-12219-2016, https://doi.org/10.5194/acp-16-12219-2016, 2016
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We present surface seawater measurements of bromo- and iodocarbons, which are involved in numerous atmospheric processes such as tropospheric and stratospheric ozone chemistry, from the highly productive Peruvian upwelling. By combining trace gas measurements, characterization of organic matter and phytoplankton species, and tropospheric modelling, we show that large amounts of iodocarbons produced from the pool of organic matter may contribute strongly to local tropospheric iodine loading.
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.
Luisa Galgani and Anja Engel
Biogeosciences, 13, 2453–2473, https://doi.org/10.5194/bg-13-2453-2016, https://doi.org/10.5194/bg-13-2453-2016, 2016
Anja Engel and Luisa Galgani
Biogeosciences, 13, 989–1007, https://doi.org/10.5194/bg-13-989-2016, https://doi.org/10.5194/bg-13-989-2016, 2016
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The sea-surface microlayer (SML) is a very thin layer at the interface between the ocean and the atmosphere. Organic compounds in the SML may influence the exchange of gases between seawater and air, as well as primary aerosol emission. Here, we report results from the SOPRAN M91 cruise, a field study to the coastal upwelling regime off Peru's coast in 2012. Our study provides novel insight to the relationship between plankton productivity, wind speed and organic matter accumulation in the SML.
A. N. Loginova, C. Borchard, J. Meyer, H. Hauss, R. Kiko, and A. Engel
Biogeosciences, 12, 6897–6914, https://doi.org/10.5194/bg-12-6897-2015, https://doi.org/10.5194/bg-12-6897-2015, 2015
C. Borchard and A. Engel
Biogeosciences, 12, 1271–1284, https://doi.org/10.5194/bg-12-1271-2015, https://doi.org/10.5194/bg-12-1271-2015, 2015
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
S. D. Archer, S. A. Kimmance, J. A. Stephens, F. E. Hopkins, R. G. J. Bellerby, K. G. Schulz, J. Piontek, and A. Engel
Biogeosciences, 10, 1893–1908, https://doi.org/10.5194/bg-10-1893-2013, https://doi.org/10.5194/bg-10-1893-2013, 2013
J. Unger, S. Endres, N. Wannicke, A. Engel, M. Voss, G. Nausch, and M. Nausch
Biogeosciences, 10, 1483–1499, https://doi.org/10.5194/bg-10-1483-2013, https://doi.org/10.5194/bg-10-1483-2013, 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
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
Mathilde Dugenne, Marco Corrales-Ugalde, Jessica Luo, Rainer Kiko, Todd 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 Discuss., https://doi.org/10.5194/essd-2023-479, https://doi.org/10.5194/essd-2023-479, 2023
Preprint under review for ESSD
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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).
Aleksandra Cherkasheva, Rustam Manurov, Piotr Kowalczuk, Alexandra N. Loginova, Monika Zabłocka, and Astrid Bracher
EGUsphere, https://doi.org/10.5194/egusphere-2023-2495, https://doi.org/10.5194/egusphere-2023-2495, 2023
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We aimed to improve the quality of regional Greenland Sea primary production estimates. Seventy two versions of primary production model setups were tested against field data. Best performing models had local biomass and light absorption profiles. Thus by using local parametrizations for these parameters we can improve Arctic primary production model performance. Annual Greenland Sea basin estimates are larger than previously reported.
Karine Sellegri, Theresa Barthelmeß, Jonathan Trueblood, Antonia Cristi, Evelyn Freney, Clémence Rose, Neill Barr, Mike Harvey, Karl Safi, Stacy Deppeler, Karen Thompson, Wayne Dillon, Anja Engel, and Cliff Law
Atmos. Chem. Phys., 23, 12949–12964, https://doi.org/10.5194/acp-23-12949-2023, https://doi.org/10.5194/acp-23-12949-2023, 2023
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The amount of sea spray emitted to the atmosphere depends on the ocean temperature, but this dependency is not well understood, especially when ocean biology is involved. In this study, we show that sea spray emissions are increased by up to a factor of 4 at low seawater temperatures compared to moderate temperatures, and we quantify the temperature dependence as a function of the ocean biogeochemistry.
Manon Rocco, Erin Dunne, Alexia Saint-Macary, Maija Peltola, Theresa Barthelmeß, Neill Barr, Karl Safi, Andrew Marriner, Stacy Deppeler, James Harnwell, Anja Engel, Aurélie Colomb, Alfonso Saiz-Lopez, Mike Harvey, Cliff S. Law, and Karine Sellegri
EGUsphere, https://doi.org/10.5194/egusphere-2023-516, https://doi.org/10.5194/egusphere-2023-516, 2023
Preprint archived
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During the Sea2cloud campaign in the Southern Pacific Ocean, we measured air-sea emissions from phytopankton of two key atmospheric compounds: DMS and MeSH. These compounds are well-known to play a great role in atmospheric chemistry and climate. We see in this paper that these compounds are most emited by the nanophytoplankton population. We provide here parameters for climate models to predict future trends of the emissions of these compounds and their roles and impacts on the global warming.
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.
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.
Lin Yang, Jing Zhang, Anja Engel, and Gui-Peng Yang
Biogeosciences, 19, 5251–5268, https://doi.org/10.5194/bg-19-5251-2022, https://doi.org/10.5194/bg-19-5251-2022, 2022
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Enrichment factors of dissolved organic matter (DOM) in the eastern marginal seas of China exhibited a significant spatio-temporal variation. Photochemical and enrichment processes co-regulated DOM enrichment in the sea-surface microlayer (SML). Autochthonous DOM was more frequently enriched in the SML than terrestrial DOM. DOM in the sub-surface water exhibited higher aromaticity than that in the SML.
Quentin Devresse, Kevin W. Becker, Arne Bendinger, Johannes Hahn, and Anja Engel
Biogeosciences, 19, 5199–5219, https://doi.org/10.5194/bg-19-5199-2022, https://doi.org/10.5194/bg-19-5199-2022, 2022
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Eddies are ubiquitous in the ocean and alter physical, chemical, and biological processes. However, how they affect organic carbon production and consumption is largely unknown. Here we show how an eddy triggers a cascade effect on biomass production and metabolic activities of phyto- and bacterioplankton. Our results may contribute to the improvement of biogeochemical models used to estimate carbon fluxes in the ocean.
Theresa Barthelmeß and Anja Engel
Biogeosciences, 19, 4965–4992, https://doi.org/10.5194/bg-19-4965-2022, https://doi.org/10.5194/bg-19-4965-2022, 2022
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Greenhouse gases released by human activity cause a global rise in mean temperatures. While scientists can predict how much of these gases accumulate in the atmosphere based on not only human-derived sources but also oceanic sinks, it is rather difficult to predict the major influence of coastal ecosystems. We provide a detailed study on the occurrence, composition, and controls of substances that suppress gas exchange. We thus help to determine what controls coastal greenhouse gas fluxes.
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.
Natalia Belkin, Tamar Guy-Haim, Maxim Rubin-Blum, Ayah Lazar, Guy Sisma-Ventura, Rainer Kiko, Arseniy R. Morov, Tal Ozer, Isaac Gertman, Barak Herut, and Eyal Rahav
Ocean Sci., 18, 693–715, https://doi.org/10.5194/os-18-693-2022, https://doi.org/10.5194/os-18-693-2022, 2022
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We studied how distinct water circulations that elevate (cyclone) or descend (anticyclone) water from the upper ocean affect the biomass, activity and diversity of planktonic microorganisms in the impoverished eastern Mediterranean. We show that cyclonic and anticyclonic eddies differ in their community composition and production. Moreover, the anticyclone may be a potential bio-invasion and dispersal vector, while the cyclone may serve as a thermal refugee for native species.
Manuela van Pinxteren, Tiera-Brandy Robinson, Sebastian Zeppenfeld, Xianda Gong, Enno Bahlmann, Khanneh Wadinga Fomba, Nadja Triesch, Frank Stratmann, Oliver Wurl, Anja Engel, Heike Wex, and Hartmut Herrmann
Atmos. Chem. Phys., 22, 5725–5742, https://doi.org/10.5194/acp-22-5725-2022, https://doi.org/10.5194/acp-22-5725-2022, 2022
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A class of marine particles (transparent exopolymer particles, TEPs) that is ubiquitously found in the world oceans was measured for the first time in ambient marine aerosol particles and marine cloud waters in the tropical Atlantic Ocean. TEPs are likely to have good properties for influencing clouds. We show that TEPs are transferred from the ocean to the marine atmosphere via sea-spray formation and our results suggest that they can also form directly in aerosol particles and in cloud water.
France Van Wambeke, Vincent Taillandier, Karine Desboeufs, Elvira Pulido-Villena, Julie Dinasquet, Anja Engel, Emilio Marañón, Céline Ridame, and Cécile Guieu
Biogeosciences, 18, 5699–5717, https://doi.org/10.5194/bg-18-5699-2021, https://doi.org/10.5194/bg-18-5699-2021, 2021
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Simultaneous in situ measurements of (dry and wet) atmospheric deposition and biogeochemical stocks and fluxes in the sunlit waters of the open Mediterranean Sea revealed complex physical and biological processes occurring within the mixed layer. Nitrogen (N) budgets were computed to compare the sources and sinks of N in the mixed layer. The transitory effect observed after a wet dust deposition impacted the microbial food web down to the deep chlorophyll maximum.
Frédéric Gazeau, France Van Wambeke, Emilio Marañón, Maria Pérez-Lorenzo, Samir Alliouane, Christian Stolpe, Thierry Blasco, Nathalie Leblond, Birthe Zäncker, Anja Engel, Barbara Marie, Julie Dinasquet, and Cécile Guieu
Biogeosciences, 18, 5423–5446, https://doi.org/10.5194/bg-18-5423-2021, https://doi.org/10.5194/bg-18-5423-2021, 2021
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Our study shows that the impact of dust deposition on primary production depends on the initial composition and metabolic state of the tested community and is constrained by the amount of nutrients added, to sustain both the fast response of heterotrophic prokaryotes and the delayed one of phytoplankton. Under future environmental conditions, heterotrophic metabolism will be more impacted than primary production, therefore reducing the capacity of surface waters to sequester anthropogenic CO2.
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.
Evelyn Freney, Karine Sellegri, Alessia Nicosia, Leah R. Williams, Matteo Rinaldi, Jonathan T. Trueblood, André S. H. Prévôt, Melilotus Thyssen, Gérald Grégori, Nils Haëntjens, Julie Dinasquet, Ingrid Obernosterer, France Van Wambeke, Anja Engel, Birthe Zäncker, Karine Desboeufs, Eija Asmi, Hilkka Timonen, and Cécile Guieu
Atmos. Chem. Phys., 21, 10625–10641, https://doi.org/10.5194/acp-21-10625-2021, https://doi.org/10.5194/acp-21-10625-2021, 2021
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In this work, we present observations of the organic aerosol content in primary sea spray aerosols (SSAs) continuously generated along a 5-week cruise in the Mediterranean. This information is combined with seawater biogeochemical properties also measured continuously along the ship track to develop a number of parametrizations that can be used in models to determine SSA organic content in oligotrophic waters that represent 60 % of the oceans from commonly measured seawater variables.
Mariana Hill Cruz, Iris Kriest, Yonss Saranga José, Rainer Kiko, Helena Hauss, and Andreas Oschlies
Biogeosciences, 18, 2891–2916, https://doi.org/10.5194/bg-18-2891-2021, https://doi.org/10.5194/bg-18-2891-2021, 2021
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In this study we use a regional biogeochemical model of the eastern tropical South Pacific Ocean to implicitly simulate the effect that fluctuations in populations of small pelagic fish, such as anchovy and sardine, may have on the biogeochemistry of the northern Humboldt Current System. To do so, we vary the zooplankton mortality in the model, under the assumption that these fishes eat zooplankton. We also evaluate the model for the first time against mesozooplankton observations.
Gerd Krahmann, Damian L. Arévalo-Martínez, Andrew W. Dale, Marcus Dengler, Anja Engel, Nicolaas Glock, Patricia Grasse, Johannes Hahn, Helena Hauss, Mark Hopwood, Rainer Kiko, Alexandra Loginova, Carolin R. Löscher, Marie Maßmig, Alexandra-Sophie Roy, Renato Salvatteci, Stefan Sommer, Toste Tanhua, and Hela Mehrtens
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2020-308, https://doi.org/10.5194/essd-2020-308, 2021
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The project "Climate-Biogeochemistry Interactions in the Tropical Ocean" (SFB 754) was a multidisciplinary research project active from 2008 to 2019 aimed at a better understanding of the coupling between the tropical climate and ocean circulation and the ocean's oxygen and nutrient balance. On 34 research cruises, mainly in the Southeast Tropical Pacific and the Northeast Tropical Atlantic, 1071 physical, chemical and biological data sets were collected.
France Van Wambeke, Elvira Pulido, Philippe Catala, Julie Dinasquet, Kahina Djaoudi, Anja Engel, Marc Garel, Sophie Guasco, Barbara Marie, Sandra Nunige, Vincent Taillandier, Birthe Zäncker, and Christian Tamburini
Biogeosciences, 18, 2301–2323, https://doi.org/10.5194/bg-18-2301-2021, https://doi.org/10.5194/bg-18-2301-2021, 2021
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Michaelis–Menten kinetics were determined for alkaline phosphatase, aminopeptidase and β-glucosidase in the Mediterranean Sea. Although the ectoenzymatic-hydrolysis contribution to heterotrophic prokaryotic needs was high in terms of N, it was low in terms of C. This study points out the biases in interpretation of the relative differences in activities among the three tested enzymes in regard to the choice of added concentrations of fluorogenic substrates.
Jonathan V. Trueblood, Alessia Nicosia, Anja Engel, Birthe Zäncker, Matteo Rinaldi, Evelyn Freney, Melilotus Thyssen, Ingrid Obernosterer, Julie Dinasquet, Franco Belosi, Antonio Tovar-Sánchez, Araceli Rodriguez-Romero, Gianni Santachiara, Cécile Guieu, and Karine Sellegri
Atmos. Chem. Phys., 21, 4659–4676, https://doi.org/10.5194/acp-21-4659-2021, https://doi.org/10.5194/acp-21-4659-2021, 2021
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Sea spray aerosols (SSAs) can be an important source of ice-nucleating particles (INPs) that impact cloud properties over the oceans. In the Mediterranean Sea, we found that the INPs in the seawater surface microlayer increased by an order of magnitude after a rain dust event that impacted iron and bacterial abundances. The INP properties of SSA (INPSSA) increased after a 3 d delay. Outside this event, INPSSA could be parameterized as a function of the seawater biogeochemistry.
Birthe Zäncker, Michael Cunliffe, and Anja Engel
Biogeosciences, 18, 2107–2118, https://doi.org/10.5194/bg-18-2107-2021, https://doi.org/10.5194/bg-18-2107-2021, 2021
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Fungi are found in numerous marine environments. Our study found an increased importance of fungi in the Ionian Sea, where bacterial and phytoplankton counts were reduced, but organic matter was still available, suggesting fungi might benefit from the reduced competition from bacteria in low-nutrient, low-chlorophyll (LNLC) regions.
Emilio Marañón, France Van Wambeke, Julia Uitz, Emmanuel S. Boss, Céline Dimier, Julie Dinasquet, Anja Engel, Nils Haëntjens, María Pérez-Lorenzo, Vincent Taillandier, and Birthe Zäncker
Biogeosciences, 18, 1749–1767, https://doi.org/10.5194/bg-18-1749-2021, https://doi.org/10.5194/bg-18-1749-2021, 2021
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The concentration of chlorophyll is commonly used as an indicator of the abundance of photosynthetic plankton (phytoplankton) in lakes and oceans. Our study investigates why a deep chlorophyll maximum, located near the bottom of the upper, illuminated layer develops in the Mediterranean Sea. We find that the acclimation of cells to low light is the main mechanism involved and that this deep maximum represents also a maximum in the biomass and carbon fixation activity of phytoplankton.
Nadja Triesch, Manuela van Pinxteren, Anja Engel, and Hartmut Herrmann
Atmos. Chem. Phys., 21, 163–181, https://doi.org/10.5194/acp-21-163-2021, https://doi.org/10.5194/acp-21-163-2021, 2021
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To investigate the sources of free amino acids (FAAs) in the marine atmosphere, concerted measurements (the simultaneous investigation of seawater, size-segregated aerosol particles and cloud water) were performed at the Cabo Verde islands. This study describes the transfer of FAAs as part of organic matter from the ocean into the atmosphere on a molecular level. In the investigated marine environment, a high enrichment of FAAs in submicron aerosol particles and in cloud droplets was observed.
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.
Alexandra N. Loginova, Andrew W. Dale, Frédéric A. C. Le Moigne, Sören Thomsen, Stefan Sommer, David Clemens, Klaus Wallmann, and Anja Engel
Biogeosciences, 17, 4663–4679, https://doi.org/10.5194/bg-17-4663-2020, https://doi.org/10.5194/bg-17-4663-2020, 2020
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We measured dissolved organic carbon (DOC), nitrogen (DON) and matter (DOM) optical properties in pore waters and near-bottom waters of the eastern tropical South Pacific off Peru. The difference between diffusion-driven and net fluxes of DOC and DON and qualitative changes in DOM optical properties suggested active microbial utilisation of the released DOM at the sediment–water interface. Our results suggest that the sediment release of DOM contributes to microbial processes in the area.
Sebastian Zeppenfeld, Manuela van Pinxteren, Anja Engel, and Hartmut Herrmann
Ocean Sci., 16, 817–830, https://doi.org/10.5194/os-16-817-2020, https://doi.org/10.5194/os-16-817-2020, 2020
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An analytical method combining electro-dialysis with high-performance anionic exchange chromatography coupled to pulsed amperometric detection was developed and optimized for analyzing free and combined carbohydrates in seawater and other saline environmental samples.
Antonio Tovar-Sánchez, Araceli Rodríguez-Romero, Anja Engel, Birthe Zäncker, Franck Fu, Emilio Marañón, María Pérez-Lorenzo, Matthieu Bressac, Thibaut Wagener, Sylvain Triquet, Guillaume Siour, Karine Desboeufs, and Cécile Guieu
Biogeosciences, 17, 2349–2364, https://doi.org/10.5194/bg-17-2349-2020, https://doi.org/10.5194/bg-17-2349-2020, 2020
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Residence times of particulate metals derived from aerosol deposition in the Sea Surface Microlayer of the Mediterranean Sea ranged from a couple of minutes (e.g., for Fe) to a few hours (e.g., for Cu). Microbial activity seems to play an important role in in this process and in the concentration and distribution of metals between diferent water layers.
Marie Maßmig, Jan Lüdke, Gerd Krahmann, and Anja Engel
Biogeosciences, 17, 215–230, https://doi.org/10.5194/bg-17-215-2020, https://doi.org/10.5194/bg-17-215-2020, 2020
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Little is known about the rates of bacterial element cycling in oxygen minimum zones (OMZs). We measured bacterial production and rates of extracellular hydrolytic enzymes at various in situ oxygen concentrations in the OMZ off Peru. Our field data show unhampered bacterial activity at low oxygen concentrations. Meanwhile bacterial degradation of organic matter substantially contributed to the formation of the OMZ.
Henk-Jan Hoving, Svenja Christiansen, Eduard Fabrizius, Helena Hauss, Rainer Kiko, Peter Linke, Philipp Neitzel, Uwe Piatkowski, and Arne Körtzinger
Ocean Sci., 15, 1327–1340, https://doi.org/10.5194/os-15-1327-2019, https://doi.org/10.5194/os-15-1327-2019, 2019
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The pelagic in situ observation system (PELAGIOS) is a towed observation system with HD video camera and environmental sensors. It is used for pelagic video transects down to 3000 m. The system enables the visualization and exploration of pelagic organisms (> 1 cm), in particular delicate gelatinous fauna, which cannot be captured by nets. The video and hydrographic data give insight into the biodiversity, abundance, and distribution of oceanic pelagic organisms from the surface to the deep sea.
Alexandra N. Loginova, Sören Thomsen, Marcus Dengler, Jan Lüdke, and Anja Engel
Biogeosciences, 16, 2033–2047, https://doi.org/10.5194/bg-16-2033-2019, https://doi.org/10.5194/bg-16-2033-2019, 2019
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High primary production in the Peruvian upwelling system is followed by rapid heterotrophic utilization of organic matter and supports the formation of one of the most intense oxygen minimum zones (OMZs) in the world. Here, we estimated vertical fluxes of oxygen and dissolved organic matter (DOM) from the surface to the OMZ. Our results suggest that DOM remineralization substantially reduces oxygen concentration in the upper water column and controls the shape of the upper oxycline.
Soeren Thomsen, Johannes Karstensen, Rainer Kiko, Gerd Krahmann, Marcus Dengler, and Anja Engel
Biogeosciences, 16, 979–998, https://doi.org/10.5194/bg-16-979-2019, https://doi.org/10.5194/bg-16-979-2019, 2019
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Physical and biogeochemical observations from an autonomous underwater vehicle in combination with ship-based measurements are used to investigate remote and local drivers of the oxygen and nutrient variability off Mauritania. Beside the transport of oxygen and nutrients characteristics from remote areas towards Mauritania also local remineralization of organic material close to the seabed seems to be important for the distribution of oxygen and nutrients.
Carolina Cisternas-Novoa, Frédéric A. C. Le Moigne, and Anja Engel
Biogeosciences, 16, 927–947, https://doi.org/10.5194/bg-16-927-2019, https://doi.org/10.5194/bg-16-927-2019, 2019
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We investigate the composition and vertical fluxes of POM in two deep basins of the Baltic Sea (GB: Gotland Basin and LD: Landsort Deep). The two basins showed different O2 regimes resulting from the intrusion of oxygen-rich water from the North Sea that ventilated the deep waters in GB, but not in LD.
In GB, O2 intrusions lead to a high abundance of manganese oxides that aggregate with POM, altering its composition and vertical flux and contributing to a higher POC transfer efficiency in GB.
Cui-Ci Sun, Martin Sperling, and Anja Engel
Biogeosciences, 15, 3577–3589, https://doi.org/10.5194/bg-15-3577-2018, https://doi.org/10.5194/bg-15-3577-2018, 2018
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Biogenic gel particles such as transparent exopolymer particles (TEP) and Coomassie stainable particles (CSP) are important components in the sea-surface microlayer (SML). Their potential role in air–sea gas exchange and in primary organic aerosol emission has generated considerable research interest. Our wind wave channel experiment revealed how wind speed controls the accumulation and size distribution of biogenic gel particles in the SML.
Johannes Karstensen, Florian Schütte, Alice Pietri, Gerd Krahmann, Björn Fiedler, Damian Grundle, Helena Hauss, Arne Körtzinger, Carolin R. Löscher, Pierre Testor, Nuno Vieira, and Martin Visbeck
Biogeosciences, 14, 2167–2181, https://doi.org/10.5194/bg-14-2167-2017, https://doi.org/10.5194/bg-14-2167-2017, 2017
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High-resolution observational data from underwater gliders and ships are used to investigate drivers and pathways of nutrient upwelling in high-productive whirling ecosystems (eddies). The data suggest that the upwelling is created by the interaction of wind-induced internal waves with the local rotation of the eddy. Because of differences in nutrient and oxygen pathways, a low-oxygen core is established at shallow depth in the high-productive eddies.
Anja Engel, Hannes Wagner, Frédéric A. C. Le Moigne, and Samuel T. Wilson
Biogeosciences, 14, 1825–1838, https://doi.org/10.5194/bg-14-1825-2017, https://doi.org/10.5194/bg-14-1825-2017, 2017
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To better understand the role of oxygen for the biological carbon pump, we studied particle fluxes through hypoxic waters in the eastern tropical North Atlantic. Attenuation of organic carbon fluxes over depth was lower than expected from seawater temperatures, indicating co-effects of oxygen concentration. Differences were observed for individual organic components, suggesting that future carbon export fluxes may depend on changes in surface ocean organic matter quality under global change.
Florian Schütte, Johannes Karstensen, Gerd Krahmann, Helena Hauss, Björn Fiedler, Peter Brandt, Martin Visbeck, and Arne Körtzinger
Biogeosciences, 13, 5865–5881, https://doi.org/10.5194/bg-13-5865-2016, https://doi.org/10.5194/bg-13-5865-2016, 2016
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Mesoscale eddies with very low–oxygen concentrations at shallow depth have been recently discovered in the eastern tropical North Atlantic. Our analysis shows that low oxygen eddies occur more frequent than expected and are found even close to the equator (8° N). From budget calculations we show that an oxygen reduction of 7 µmol/kg in the depth range of 50–150 m in the eastern tropical North Atlantic (peak reduction is 16 µmol/kg at 100 m depth) can be associated with the dispersion of these eddies.
Björn Fiedler, Damian S. Grundle, Florian Schütte, Johannes Karstensen, Carolin R. Löscher, Helena Hauss, Hannes Wagner, Alexandra Loginova, Rainer Kiko, Péricles Silva, Toste Tanhua, and Arne Körtzinger
Biogeosciences, 13, 5633–5647, https://doi.org/10.5194/bg-13-5633-2016, https://doi.org/10.5194/bg-13-5633-2016, 2016
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Oxygen-depleted mesoscale features in the open eastern tropical North Atlantic, which are formed in the Mauritanian upwelling region, were discovered recently. This study examines biogeochemical structure and magnitudes of related processes within these isolated water masses. We found very low oxygen concentrations and strongly enhanced acidity at near-surface depth. Oxygen utilization and downward carbon export were found to exceed known values for this ocean region.
Helmke Hepach, Birgit Quack, Susann Tegtmeier, Anja Engel, Astrid Bracher, Steffen Fuhlbrügge, Luisa Galgani, Elliot L. Atlas, Johannes Lampel, Udo Frieß, and Kirstin Krüger
Atmos. Chem. Phys., 16, 12219–12237, https://doi.org/10.5194/acp-16-12219-2016, https://doi.org/10.5194/acp-16-12219-2016, 2016
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We present surface seawater measurements of bromo- and iodocarbons, which are involved in numerous atmospheric processes such as tropospheric and stratospheric ozone chemistry, from the highly productive Peruvian upwelling. By combining trace gas measurements, characterization of organic matter and phytoplankton species, and tropospheric modelling, we show that large amounts of iodocarbons produced from the pool of organic matter may contribute strongly to local tropospheric iodine loading.
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.
Luisa Galgani and Anja Engel
Biogeosciences, 13, 2453–2473, https://doi.org/10.5194/bg-13-2453-2016, https://doi.org/10.5194/bg-13-2453-2016, 2016
Rainer Kiko, Helena Hauss, Friedrich Buchholz, and Frank Melzner
Biogeosciences, 13, 2241–2255, https://doi.org/10.5194/bg-13-2241-2016, https://doi.org/10.5194/bg-13-2241-2016, 2016
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The diel vertical migration of zooplankton and nekton results in an active export of carbon and nitrogen from the oceans surface layer. In vast areas of the ocean the daytime distribution depth of migrating organisms corresponds to the core of an oxygen minimum zone (OMZ). We show that exposure to OMZ conditions can result in a strong depression of respiration and ammonium excretion in zooplankton, a fact that needs to be considered when calculating carbon and nitrogen fluxes in OMZ regions.
Helena Hauss, Svenja Christiansen, Florian Schütte, Rainer Kiko, Miryam Edvam Lima, Elizandro Rodrigues, Johannes Karstensen, Carolin R. Löscher, Arne Körtzinger, and Björn Fiedler
Biogeosciences, 13, 1977–1989, https://doi.org/10.5194/bg-13-1977-2016, https://doi.org/10.5194/bg-13-1977-2016, 2016
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In a low-oxygen eddy in the tropical Atlantic, total zooplankton biomass was increased. Larger plankton avoided the oxygen minimum zone (OMZ, < 20 µmol O2 kg−1). We identified four strategies by different plankton groups: (i) shallow OMZ avoidance and compression at surface, (ii) migration to shallow OMZ core during daytime, migration to surface at nighttime, (iii) residing in shallow OMZ day and night and (iv) migration through the shallow OMZ from oxygenated depths to surface and back.
Anja Engel and Luisa Galgani
Biogeosciences, 13, 989–1007, https://doi.org/10.5194/bg-13-989-2016, https://doi.org/10.5194/bg-13-989-2016, 2016
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The sea-surface microlayer (SML) is a very thin layer at the interface between the ocean and the atmosphere. Organic compounds in the SML may influence the exchange of gases between seawater and air, as well as primary aerosol emission. Here, we report results from the SOPRAN M91 cruise, a field study to the coastal upwelling regime off Peru's coast in 2012. Our study provides novel insight to the relationship between plankton productivity, wind speed and organic matter accumulation in the SML.
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
C. R. Löscher, M. A. Fischer, S. C. Neulinger, B. Fiedler, M. Philippi, F. Schütte, A. Singh, H. Hauss, J. Karstensen, A. Körtzinger, S. Künzel, and R. A. Schmitz
Biogeosciences, 12, 7467–7482, https://doi.org/10.5194/bg-12-7467-2015, https://doi.org/10.5194/bg-12-7467-2015, 2015
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The waters of the tropical Atlantic Open Ocean usually contain comparably high concentrations of oxygen. Now, it became clear that there are watermasses related to eddies that are nearly anoxic. We surveyed one of those eddies and found a biosphere that largely differed from the usual biosphere present in this area with a specific community responsible for primary production and for degradation processes. Further, we found the very first indication for active nitrogen loss in the open Atlantic.
A. N. Loginova, C. Borchard, J. Meyer, H. Hauss, R. Kiko, and A. Engel
Biogeosciences, 12, 6897–6914, https://doi.org/10.5194/bg-12-6897-2015, https://doi.org/10.5194/bg-12-6897-2015, 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
C. Borchard and A. Engel
Biogeosciences, 12, 1271–1284, https://doi.org/10.5194/bg-12-1271-2015, https://doi.org/10.5194/bg-12-1271-2015, 2015
B. Heim, E. Abramova, R. Doerffer, F. Günther, J. Hölemann, A. Kraberg, H. Lantuit, A. Loginova, F. Martynov, P. P. Overduin, and C. Wegner
Biogeosciences, 11, 4191–4210, https://doi.org/10.5194/bg-11-4191-2014, https://doi.org/10.5194/bg-11-4191-2014, 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
S. D. Archer, S. A. Kimmance, J. A. Stephens, F. E. Hopkins, R. G. J. Bellerby, K. G. Schulz, J. Piontek, and A. Engel
Biogeosciences, 10, 1893–1908, https://doi.org/10.5194/bg-10-1893-2013, https://doi.org/10.5194/bg-10-1893-2013, 2013
J. Unger, S. Endres, N. Wannicke, A. Engel, M. Voss, G. Nausch, and M. Nausch
Biogeosciences, 10, 1483–1499, https://doi.org/10.5194/bg-10-1483-2013, https://doi.org/10.5194/bg-10-1483-2013, 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
J. Piontek, C. Borchard, M. Sperling, K. G. Schulz, U. Riebesell, and A. Engel
Biogeosciences, 10, 297–314, https://doi.org/10.5194/bg-10-297-2013, https://doi.org/10.5194/bg-10-297-2013, 2013
M. Sperling, J. Piontek, G. Gerdts, A. Wichels, H. Schunck, A.-S. Roy, J. La Roche, J. Gilbert, J. I. Nissimov, L. Bittner, S. Romac, U. Riebesell, and A. Engel
Biogeosciences, 10, 181–191, https://doi.org/10.5194/bg-10-181-2013, https://doi.org/10.5194/bg-10-181-2013, 2013
K. G. Schulz, R. G. J. Bellerby, C. P. D. Brussaard, J. Büdenbender, J. Czerny, A. Engel, M. Fischer, S. Koch-Klavsen, S. A. Krug, S. Lischka, A. Ludwig, M. Meyerhöfer, G. Nondal, A. Silyakova, A. Stuhr, and U. Riebesell
Biogeosciences, 10, 161–180, https://doi.org/10.5194/bg-10-161-2013, https://doi.org/10.5194/bg-10-161-2013, 2013
Related subject area
Biogeochemistry: Organic Biogeochemistry
Latitudinal distribution of biomarkers across the western Arctic Ocean and the Bering Sea: an approach to assess sympagic and pelagic algal production
Sinking fate and carbon export of zooplankton fecal pellets: insights from time-series sediment trap observations in the northern South China Sea
Environmental controls on the brGDGT and brGMGT distributions across the Seine River basin (NW France): Implications for bacterial tetraethers as a proxy for riverine runoff
Low cobalt inventories in the Amundsen and Ross seas driven by high demand for labile cobalt uptake among native phytoplankton communities
Potential bioavailability of representative pyrogenic organic matter compounds in comparison to natural dissolved organic matter pools
Distributions of bacteriohopanepolyols in lakes and coastal lagoons of the Azores Archipelago
Recently fixed carbon fuels microbial activity several meters below the soil surface
Environmental and hydrologic controls on sediment and organic carbon export from a subalpine catchment: insights from a time series
Climate and geology overwrite land use effects on soil organic nitrogen cycling on a continental scale
Compositions of dissolved organic matter in the ice-covered waters above the Aurora hydrothermal vent system, Gakkel Ridge, Arctic Ocean
Organic matter characteristics of a rapidly eroding permafrost cliff in NE Siberia (Lena Delta, Laptev Sea region)
Microbial labilization and diversification of pyrogenic dissolved organic matter
Bacterial and eukaryotic intact polar lipids point to in situ production as a key source of labile organic matter in hadal surface sediment of the Atacama Trench
What can we learn from amino acids about oceanic organic matter cycling and degradation?
Bacteriohopanetetrol-x: constraining its application as a lipid biomarker for marine anammox using the water column oxygen gradient of the Benguela upwelling system
Active and passive fluxes of carbon, nitrogen, and phosphorus in the northern South China Sea
Cyanobacteria net community production in the Baltic Sea as inferred from profiling pCO2 measurements
Reviews and syntheses: Heterotrophic fixation of inorganic carbon – significant but invisible flux in environmental carbon cycling
Revised fractional abundances and warm-season temperatures substantially improve brGDGT calibrations in lake sediments
Archaeal intact polar lipids in polar waters: a comparison between the Amundsen and Scotia seas
Reproducible determination of dissolved organic matter photosensitivity
Technical note: Uncovering the influence of methodological variations on the extractability of iron-bound organic carbon
Anthropocene climate warming enhances autochthonous carbon cycling in an upland Arctic lake, Disko Island, West Greenland
Novel hydrocarbon-utilizing soil mycobacteria synthesize unique mycocerosic acids at a Sicilian everlasting fire
Alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol L−1
Seasonal variability and sources of in situ brGDGT production in a permanently stratified African crater lake
Sediment release of dissolved organic matter to the oxygen minimum zone off Peru
Better molecular preservation of organic matter in an oxic than in a sulfidic depositional environment: evidence from Thalassiphora pelagica (Dinoflagellata, Eocene) cysts
Assessing branched tetraether lipids as tracers of soil organic carbon transport through the Carminowe Creek catchment (southwest England)
The nonconservative distribution pattern of organic matter in the Rajang, a tropical river with peatland in its estuary
Predominance of hexamethylated 6-methyl branched glycerol dialkyl glycerol tetraethers in the Mariana Trench: source and environmental implication
High-pH and anoxic conditions during soil organic matter extraction increases its electron-exchange capacity and ability to stimulate microbial Fe(III) reduction by electron shuttling
Sterol preservation in hypersaline microbial mats
Structural elucidation and environmental distributions of butanetriol and pentanetriol dialkyl glycerol tetraethers (BDGTs and PDGTs)
Distribution and degradation of terrestrial organic matter in the sediments of peat-draining rivers, Sarawak, Malaysian Borneo
Validation of carbon isotope fractionation in algal lipids as a pCO2 proxy using a natural CO2 seep (Shikine Island, Japan)
Composition and cycling of dissolved organic matter from tropical peatlands of coastal Sarawak, Borneo, revealed by fluorescence spectroscopy and parallel factor analysis
Latitudinal variations in δ30Si and δ15N signatures along the Peruvian shelf: quantifying the effects of nutrient utilization versus denitrification over the past 600 years
Diapycnal dissolved organic matter supply into the upper Peruvian oxycline
Composition and vertical flux of particulate organic matter to the oxygen minimum zone of the central Baltic Sea: impact of a sporadic North Sea inflow
Main drivers of transparent exopolymer particle distribution across the surface Atlantic Ocean
Biochemical and structural controls on the decomposition dynamics of boreal upland forest moss tissues
Spatiotemporal transformation of dissolved organic matter along an alpine stream flow path on the Qinghai–Tibet Plateau: importance of source and permafrost degradation
A quest for the biological sources of long chain alkyl diols in the western tropical North Atlantic Ocean
Long-chain diols in rivers: distribution and potential biological sources
Leaf wax n-alkanes in modern plants and topsoils from eastern Georgia (Caucasus) – implications for reconstructing regional paleovegetation
The role of diatom resting spores in pelagic–benthic coupling in the Southern Ocean
Calcium content and high calcium adaptation of plants in karst areas of southwestern Hunan, China
Substrate potential of last interglacial to Holocene permafrost organic matter for future microbial greenhouse gas production
Variation pattern of particulate organic carbon and nitrogen in oceans and inland waters
Youcheng Bai, Marie-Alexandrine Sicre, Jian Ren, Vincent Klein, Haiyan Jin, and Jianfang Chen
Biogeosciences, 21, 689–709, https://doi.org/10.5194/bg-21-689-2024, https://doi.org/10.5194/bg-21-689-2024, 2024
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Algal biomarkers were used to assess sea ice and pelagic algal production across the western Arctic Ocean with changing sea-ice conditions. They show three distinct areas along with a marked latitudinal gradient of sea ice over pelagic algal production in surface sediments that are reflected by the H-Print index. Our data also show that efficient grazing consumption accounted for the dramatic decrease of diatom-derived biomarkers in sediments compared to that of particulate matter.
Hanxiao Wang, Zhifei Liu, Jiaying Li, Baozhi Lin, Yulong Zhao, Xiaodong Zhang, Junyuan Cao, Jingwen Zhang, Hongzhe Song, and Wenzhuo Wang
Biogeosciences, 20, 5109–5123, https://doi.org/10.5194/bg-20-5109-2023, https://doi.org/10.5194/bg-20-5109-2023, 2023
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The sinking of zooplankton fecal pellets is a key process in the marine biological carbon pump. This study presents carbon export of four shapes of fecal pellets from two time-series sediment traps in the South China Sea. The results show that the sinking fate of fecal pellets is regulated by marine primary productivity, deep-dwelling zooplankton community, and deep-sea currents in the tropical marginal sea, thus providing a new perspective for exploring the carbon cycle in the world ocean.
Zhe-Xuan Zhang, Edith Parlanti, Christelle Anquetil, Jérôme Morelle, Anniet Laverman, Alexandre Thibault, Elisa Bou, and Arnaud Huguet
EGUsphere, https://doi.org/10.31223/X5PQ17, https://doi.org/10.31223/X5PQ17, 2023
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Bacterial tetraethers have important implications for palaeoclimate reconstruction. However, fundamental understanding of how these lipids are transformed from land to sea and which environmental factors influence their distributions is lacking. Here, we investigate the sources of brGDGTs and brGMGTs and the factors controlling their distributions in a large dataset (n=237). We propose a novel proxy to trace riverine runoff, which is applicable in modern systems and in paleorecord.
Rebecca J. Chmiel, Riss M. Kell, Deepa Rao, Dawn M. Moran, Giacomo R. DiTullio, and Mak A. Saito
Biogeosciences, 20, 3997–4027, https://doi.org/10.5194/bg-20-3997-2023, https://doi.org/10.5194/bg-20-3997-2023, 2023
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Cobalt is an important micronutrient for plankton, yet it is often scarce throughout the oceans. A 2017/2018 expedition to coastal Antarctica, including regions of the Amundsen Sea and the Ross Sea, discovered lower concentrations of cobalt compared to two past expeditions in 2005 and 2006, particularly for the type of cobalt preferred as a nutrient by phytoplankton. This loss may be due to changing inputs of other nutrients, causing higher uptake of cobalt by plankton over the last decade.
Emily B. Graham, Hyun-Seob Song, Samantha Grieger, Vanessa A. Garayburu-Caruso, James C. Stegen, Kevin D. Bladon, and Allison N. Myers-Pigg
Biogeosciences, 20, 3449–3457, https://doi.org/10.5194/bg-20-3449-2023, https://doi.org/10.5194/bg-20-3449-2023, 2023
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Intensifying wildfires are increasing pyrogenic organic matter (PyOM) production and its impact on water quality. Recent work indicates that PyOM may have a greater impact on aquatic biogeochemistry than previously assumed, driven by higher bioavailability. We provide a full assessment of the potential bioavailability of PyOM across its chemical spectrum. We indicate that PyOM can be actively transformed within the river corridor and, therefore, may be a growing source of riverine C emissions.
Nora Richter, Ellen C. Hopmans, Danica Mitrović, Pedro M. Raposeiro, Vítor Gonçalves, Ana C. Costa, Linda A. Amaral-Zettler, Laura Villanueva, and Darci Rush
Biogeosciences, 20, 2065–2098, https://doi.org/10.5194/bg-20-2065-2023, https://doi.org/10.5194/bg-20-2065-2023, 2023
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Bacteriohopanepolyols (BHPs) are a diverse class of lipids produced by bacteria across a wide range of environments. This study characterizes the diversity of BHPs in lakes and coastal lagoons in the Azores Archipelago, as well as a co-culture enriched for methanotrophs. We highlight the potential of BHPs as taxonomic markers for bacteria associated with certain ecological niches, which can be preserved in sedimentary records.
Andrea Scheibe, Carlos A. Sierra, and Marie Spohn
Biogeosciences, 20, 827–838, https://doi.org/10.5194/bg-20-827-2023, https://doi.org/10.5194/bg-20-827-2023, 2023
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We explored carbon cycling in soils in three climate zones in Chile down to a depth of 6 m, using carbon isotopes. Our results show that microbial activity several meters below the soil surface is mostly fueled by recently fixed carbon and that strong decomposition of soil organic matter only occurs in the upper decimeters of the soils. The study shows that different layers of the critical zone are tightly connected and that processes in the deep soil depend on recently fixed carbon.
Melissa Sophia Schwab, Hannah Gies, Chantal Valérie Freymond, Maarten Lupker, Negar Haghipour, and Timothy Ian Eglinton
Biogeosciences, 19, 5591–5616, https://doi.org/10.5194/bg-19-5591-2022, https://doi.org/10.5194/bg-19-5591-2022, 2022
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The majority of river studies focus on headwater or floodplain systems, while often neglecting intermediate river segments. Our study on the subalpine Sihl River bridges the gap between streams and lowlands and demonstrates that moderately steep river segments are areas of significant instream alterations, modulating the export of organic carbon over short distances.
Lisa Noll, Shasha Zhang, Qing Zheng, Yuntao Hu, Florian Hofhansl, and Wolfgang Wanek
Biogeosciences, 19, 5419–5433, https://doi.org/10.5194/bg-19-5419-2022, https://doi.org/10.5194/bg-19-5419-2022, 2022
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Cleavage of proteins to smaller nitrogen compounds allows microorganisms and plants to exploit the largest nitrogen reservoir in soils and is considered the bottleneck in soil organic nitrogen cycling. Results from soils covering a European transect show that protein turnover is constrained by soil geochemistry, shifts in climate and associated alterations in soil weathering and should be considered as a driver of soil nitrogen availability with repercussions on carbon cycle processes.
Muhammed Fatih Sert, Helge Niemann, Eoghan P. Reeves, Mats A. Granskog, Kevin P. Hand, Timo Kekäläinen, Janne Jänis, Pamela E. Rossel, Bénédicte Ferré, Anna Silyakova, and Friederike Gründger
Biogeosciences, 19, 2101–2120, https://doi.org/10.5194/bg-19-2101-2022, https://doi.org/10.5194/bg-19-2101-2022, 2022
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We investigate organic matter composition in the Arctic Ocean water column. We collected seawater samples from sea ice to deep waters at six vertical profiles near an active hydrothermal vent and its plume. In comparison to seawater, we found that the organic matter in waters directly affected by the hydrothermal plume had different chemical composition. We suggest that hydrothermal processes may influence the organic matter distribution in the deep ocean.
Charlotte Haugk, Loeka L. Jongejans, Kai Mangelsdorf, Matthias Fuchs, Olga Ogneva, Juri Palmtag, Gesine Mollenhauer, Paul J. Mann, P. Paul Overduin, Guido Grosse, Tina Sanders, Robyn E. Tuerena, Lutz Schirrmeister, Sebastian Wetterich, Alexander Kizyakov, Cornelia Karger, and Jens Strauss
Biogeosciences, 19, 2079–2094, https://doi.org/10.5194/bg-19-2079-2022, https://doi.org/10.5194/bg-19-2079-2022, 2022
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Buried animal and plant remains (carbon) from the last ice age were freeze-locked in permafrost. At an extremely fast eroding permafrost cliff in the Lena Delta (Siberia), we found this formerly frozen carbon well preserved. Our results show that ongoing degradation releases substantial amounts of this carbon, making it available for future carbon emissions. This mobilisation at the studied cliff and also similarly eroding sites bear the potential to affect rivers and oceans negatively.
Aleksandar I. Goranov, Andrew S. Wozniak, Kyle W. Bostick, Andrew R. Zimmerman, Siddhartha Mitra, and Patrick G. Hatcher
Biogeosciences, 19, 1491–1514, https://doi.org/10.5194/bg-19-1491-2022, https://doi.org/10.5194/bg-19-1491-2022, 2022
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Wildfire-derived molecules are ubiquitous in the aquatic environment, but their biological fate remains understudied. We have evaluated the compositional changes that occur to wildfire-derived molecules after incubation with soil microbes. We observe a significant degradation but also a production of numerous new labile molecules. Our results indicate that wildfire-derived molecules can be broken down and the carbon and nitrogen therein can be incorporated into microbial food webs.
Edgart Flores, Sebastian I. Cantarero, Paula Ruiz-Fernández, Nadia Dildar, Matthias Zabel, Osvaldo Ulloa, and Julio Sepúlveda
Biogeosciences, 19, 1395–1420, https://doi.org/10.5194/bg-19-1395-2022, https://doi.org/10.5194/bg-19-1395-2022, 2022
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In this study, we investigate the chemical diversity and abundance of microbial lipids as markers of organic matter sources in the deepest points of the Atacama Trench sediments and compare them to similar lipid stocks in shallower surface sediments and in the overlying water column. We evaluate possible organic matter provenance and some potential chemical adaptations of the in situ microbial community to the extreme conditions of high hydrostatic pressure in hadal realm.
Birgit Gaye, Niko Lahajnar, Natalie Harms, Sophie Anna Luise Paul, Tim Rixen, and Kay-Christian Emeis
Biogeosciences, 19, 807–830, https://doi.org/10.5194/bg-19-807-2022, https://doi.org/10.5194/bg-19-807-2022, 2022
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Amino acids were analyzed in a large number of samples of particulate and dissolved organic matter from coastal regions and the open ocean. A statistical analysis produced two new biogeochemical indicators. An indicator of sinking particle and sediment degradation (SDI) traces the degradation of organic matter from the surface waters into the sediments. A second indicator shows the residence time of suspended matter in the ocean (RTI).
Zoë R. van Kemenade, Laura Villanueva, Ellen C. Hopmans, Peter Kraal, Harry J. Witte, Jaap S. Sinninghe Damsté, and Darci Rush
Biogeosciences, 19, 201–221, https://doi.org/10.5194/bg-19-201-2022, https://doi.org/10.5194/bg-19-201-2022, 2022
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Anaerobic ammonium oxidation (anammox) is an important nitrogen-removal process in the ocean. We assess the distribution of bacteriohopanetetrol-x (BHT-x), used to trace past anammox, along a redox gradient in the water column of the Benguela upwelling system. BHT-x / BHT ratios of >0.18 correspond to the presence of living anammox bacteria and oxygen levels <50 μmol L−1. This allows for a more robust application of BHT-x to trace past marine anammox and deoxygenation in dynamic marine systems.
Jia-Jang Hung, Ching-Han Tung, Zong-Ying Lin, Yuh-ling Lee Chen, Shao-Hung Peng, Yen-Huei Lin, and Li-Shan Tsai
Biogeosciences, 18, 5141–5162, https://doi.org/10.5194/bg-18-5141-2021, https://doi.org/10.5194/bg-18-5141-2021, 2021
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We report measured active and passive fluxes and their controlling mechanisms in the northern South China Sea (NSCS). The total fluxes were higher than most reports in open oceans, indicating the significance of NSCS in atmospheric CO2 uptake and in storing that CO2 in the ocean’s interior. Winter cooling and extreme events enhanced nutrient availability and elevated fluxes. Global warming may have profound impacts on reducing ocean’s uptake and storage of CO2 in subtropical–tropical oceans.
Jens Daniel Müller, Bernd Schneider, Ulf Gräwe, Peer Fietzek, Marcus Bo Wallin, Anna Rutgersson, Norbert Wasmund, Siegfried Krüger, and Gregor Rehder
Biogeosciences, 18, 4889–4917, https://doi.org/10.5194/bg-18-4889-2021, https://doi.org/10.5194/bg-18-4889-2021, 2021
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Based on profiling pCO2 measurements from a field campaign, we quantify the biomass production of a cyanobacteria bloom in the Baltic Sea, the export of which would foster deep water deoxygenation. We further demonstrate how this biomass production can be accurately reconstructed from long-term surface measurements made on cargo vessels in combination with modelled temperature profiles. This approach enables a better understanding of a severe concern for the Baltic’s good environmental status.
Alexander Braun, Marina Spona-Friedl, Maria Avramov, Martin Elsner, Federico Baltar, Thomas Reinthaler, Gerhard J. Herndl, and Christian Griebler
Biogeosciences, 18, 3689–3700, https://doi.org/10.5194/bg-18-3689-2021, https://doi.org/10.5194/bg-18-3689-2021, 2021
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It is known that CO2 fixation by photoautotrophic organisms is the major sink from the atmosphere. While biologists are aware that CO2 fixation also occurs in heterotrophic organisms, this route of inorganic carbon, and its quantitative role, is hardly recognized in biogeochemistry. We demonstrate that a considerable amount of CO2 is fixed annually through anaplerotic reactions in heterotrophic organisms, and a significant quantity of inorganic carbon is temporally sequestered in biomass.
Jonathan H. Raberg, David J. Harning, Sarah E. Crump, Greg de Wet, Aria Blumm, Sebastian Kopf, Áslaug Geirsdóttir, Gifford H. Miller, and Julio Sepúlveda
Biogeosciences, 18, 3579–3603, https://doi.org/10.5194/bg-18-3579-2021, https://doi.org/10.5194/bg-18-3579-2021, 2021
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BrGDGT lipids are a proxy for temperature in lake sediments, but other parameters like pH can influence them, and seasonality can affect the temperatures they record. We find a warm-season bias at 43 new high-latitude sites. We also present a new method that deconvolves the effects of temperature, pH, and conductivity and generate global calibrations for these variables. Our study provides new paleoclimate tools, insight into brGDGTs at the biochemical level, and a new method for future study.
Charlotte L. Spencer-Jones, Erin L. McClymont, Nicole J. Bale, Ellen C. Hopmans, Stefan Schouten, Juliane Müller, E. Povl Abrahamsen, Claire Allen, Torsten Bickert, Claus-Dieter Hillenbrand, Elaine Mawbey, Victoria Peck, Aleksandra Svalova, and James A. Smith
Biogeosciences, 18, 3485–3504, https://doi.org/10.5194/bg-18-3485-2021, https://doi.org/10.5194/bg-18-3485-2021, 2021
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Long-term ocean temperature records are needed to fully understand the impact of West Antarctic Ice Sheet collapse. Glycerol dialkyl glycerol tetraethers (GDGTs) are powerful tools for reconstructing ocean temperature but can be difficult to apply to the Southern Ocean. Our results show active GDGT synthesis in relatively warm depths of the ocean. This research improves the application of GDGT palaeoceanographic proxies in the Southern Ocean.
Alec W. Armstrong, Leanne Powers, and Michael Gonsior
Biogeosciences, 18, 3367–3390, https://doi.org/10.5194/bg-18-3367-2021, https://doi.org/10.5194/bg-18-3367-2021, 2021
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Living things decay into organic matter, which can dissolve into water (like tea brewing). Tea receives its color by absorbing light. Similarly, this material absorbs light, which can then cause chemical reactions that change it. By measuring changes in these optical properties, we found that materials from some places are more sensitive to light than others. Comparing sensitivity to light helps us understand where these materials come from and what happens as they move through water.
Ben J. Fisher, Johan C. Faust, Oliver W. Moore, Caroline L. Peacock, and Christian März
Biogeosciences, 18, 3409–3419, https://doi.org/10.5194/bg-18-3409-2021, https://doi.org/10.5194/bg-18-3409-2021, 2021
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Organic carbon can be protected from microbial degradation in marine sediments through association with iron minerals on 1000-year timescales. Despite the importance of this carbon sink, our spatial and temporal understanding of iron-bound organic carbon interactions globally is poor. Here we show that caution must be applied when comparing quantification of iron-bound organic carbon extracted by different methods as the extraction strength and method specificity can be highly variable.
Mark A. Stevenson, Suzanne McGowan, Emma J. Pearson, George E. A. Swann, Melanie J. Leng, Vivienne J. Jones, Joseph J. Bailey, Xianyu Huang, and Erika Whiteford
Biogeosciences, 18, 2465–2485, https://doi.org/10.5194/bg-18-2465-2021, https://doi.org/10.5194/bg-18-2465-2021, 2021
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We link detailed stable isotope and biomarker analyses from the catchments of three Arctic upland lakes on Disko Island (West Greenland) to a recent dated sediment core to understand how carbon cycling has changed over the past ~500 years. We find that the carbon deposited in sediments in these upland lakes is predominately sourced from in-lake production due to the catchment's limited terrestrial vegetation and elevation and that recent increases in algal production link with climate change.
Nadine T. Smit, Laura Villanueva, Darci Rush, Fausto Grassa, Caitlyn R. Witkowski, Mira Holzheimer, Adriaan J. Minnaard, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 18, 1463–1479, https://doi.org/10.5194/bg-18-1463-2021, https://doi.org/10.5194/bg-18-1463-2021, 2021
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Soils from an everlasting fire (gas seep) in Sicily, Italy, reveal high relative abundances of novel uncultivated mycobacteria and unique 13C-depleted mycocerosic acids (multi-methyl branched fatty acids) close to the main gas seep. Our results imply that mycocerosic acids in combination with their depleted δ13C values offer a new biomarker tool to study the role of soil mycobacteria as hydrocarbon consumers in the modern and past global carbon cycle.
Marcus P. S. Badger
Biogeosciences, 18, 1149–1160, https://doi.org/10.5194/bg-18-1149-2021, https://doi.org/10.5194/bg-18-1149-2021, 2021
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Reconstructing ancient atmospheric CO2 is an important aim of palaeoclimate science in order to understand the Earth's climate system. One method, the alkenone proxy based on molecular fossils of coccolithophores, has been recently shown to be ineffective at low-to-moderate CO2 levels. In this paper I show that this is likely due to changes in the biogeochemistry of the coccolithophores when there is low carbon availability, but for much of the Cenozoic the alkenone proxy should have utility.
Loes G. J. van Bree, Francien Peterse, Allix J. Baxter, Wannes De Crop, Sigrid van Grinsven, Laura Villanueva, Dirk Verschuren, and Jaap S. Sinninghe Damsté
Biogeosciences, 17, 5443–5463, https://doi.org/10.5194/bg-17-5443-2020, https://doi.org/10.5194/bg-17-5443-2020, 2020
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Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are used as a paleothermometer based on their temperature dependence in global soils, but aquatic production complicates their use in lakes. BrGDGTs in the water column of Lake Chala, East Africa, respond to oxygen conditions and mixing. Changes in their signal can be linked to bacterial community composition rather than membrane adaptation to changing conditions. Their integrated signal in the sediment reflects mean air temperature.
Alexandra N. Loginova, Andrew W. Dale, Frédéric A. C. Le Moigne, Sören Thomsen, Stefan Sommer, David Clemens, Klaus Wallmann, and Anja Engel
Biogeosciences, 17, 4663–4679, https://doi.org/10.5194/bg-17-4663-2020, https://doi.org/10.5194/bg-17-4663-2020, 2020
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We measured dissolved organic carbon (DOC), nitrogen (DON) and matter (DOM) optical properties in pore waters and near-bottom waters of the eastern tropical South Pacific off Peru. The difference between diffusion-driven and net fluxes of DOC and DON and qualitative changes in DOM optical properties suggested active microbial utilisation of the released DOM at the sediment–water interface. Our results suggest that the sediment release of DOM contributes to microbial processes in the area.
Gerard J. M. Versteegh, Alexander J. P. Houben, and Karin A. F. Zonneveld
Biogeosciences, 17, 3545–3561, https://doi.org/10.5194/bg-17-3545-2020, https://doi.org/10.5194/bg-17-3545-2020, 2020
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Anoxic sediments mostly contain much more organic matter than oxic ones, and therefore organic matter in anoxic settings is often considered to be preserved better than in oxic settings. However, through the analysis of the same fossil dinoflagellate cyst species from both oxic and anoxic settings, we show that at a molecular level the preservation in the oxic sediments may be better since in the anoxic setting the cyst macromolecule has been altered by postdepositional modification.
Jingjing Guo, Miriam Glendell, Jeroen Meersmans, Frédérique Kirkels, Jack J. Middelburg, and Francien Peterse
Biogeosciences, 17, 3183–3201, https://doi.org/10.5194/bg-17-3183-2020, https://doi.org/10.5194/bg-17-3183-2020, 2020
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The fluxes of soil organic carbon (OC) transport from land to sea are poorly constrained, mostly due to the lack of a specific tracer for soil OC. Here we evaluate the use of specific molecules derived from soil bacteria as a tracer for soil OC in a small river catchment. We find that the initial soil signal is lost upon entering the aquatic environment. However, the local environmental history of the catchment is reflected by these molecules in the lake sediments that act as their sink.
Zhuo-Yi Zhu, Joanne Oakes, Bradley Eyre, Youyou Hao, Edwin Sien Aun Sia, Shan Jiang, Moritz Müller, and Jing Zhang
Biogeosciences, 17, 2473–2485, https://doi.org/10.5194/bg-17-2473-2020, https://doi.org/10.5194/bg-17-2473-2020, 2020
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Samples were collected in August 2016 in the Rajang River and its estuary, with tropical forest in the river basin and peatland in the estuary. Organic matter composition was influenced by transportation in the river basin, whereas peatland added clear biodegraded parts to the fluvial organic matter, which implies modification of the initial lability and/or starting points in the subsequent degradation and alternation processes after the organic matter enters the sea.
Wenjie Xiao, Yasong Wang, Yongsheng Liu, Xi Zhang, Linlin Shi, and Yunping Xu
Biogeosciences, 17, 2135–2148, https://doi.org/10.5194/bg-17-2135-2020, https://doi.org/10.5194/bg-17-2135-2020, 2020
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The hadal zone (6–11 km depth) is the least explored habitat on Earth. We studied microbial branched glycerol dialkyl glycerol tetraethers (brGDGTs) in the Challenger Deep, Mariana Trench. One unique feature is the strong predominance of 6-methyl brGDGT, which likely reflects an adaption of brGDGT-producing bacteria to alkaline seawater and low temperature. BrGDGTs, with elemental and isotopic data, suggest an autochthonous product for brGDGT. A new approach is proposed for brGDGT sourcing.
Yuge Bai, Edisson Subdiaga, Stefan B. Haderlein, Heike Knicker, and Andreas Kappler
Biogeosciences, 17, 683–698, https://doi.org/10.5194/bg-17-683-2020, https://doi.org/10.5194/bg-17-683-2020, 2020
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Biogeochemical processes of SOM are key for greenhouse gas emission and water quality. We extracted SOM by water or by NaOH–HCl under oxic–anoxic conditions. Chemical and anoxic extractions lead to higher SOM electron exchange capacities, resulting in stimulation of microbial Fe(III) reduction. Therefore, aqueous pH-neutral SOM extracts should be used to reflect environmental SOM redox processes, and artifacts of chemical extractions need to be considered when evaluating SOM redox processes.
Yan Shen, Volker Thiel, Pablo Suarez-Gonzalez, Sebastiaan W. Rampen, and Joachim Reitner
Biogeosciences, 17, 649–666, https://doi.org/10.5194/bg-17-649-2020, https://doi.org/10.5194/bg-17-649-2020, 2020
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Today, sterols are widespread in plants, animals, and fungi but are almost absent in the oldest rocks. Microbial mats, representing the earliest complex ecosystems on Earth, were omnipresent in Precambrian marine environments and may have degraded the sterols at that time. Here we analyze the distribution of sterols through a microbial mat. This provides insight into how variations in biological and nonbiological factors affect the preservation of sterols in modern and ancient microbial mats.
Sarah Coffinet, Travis B. Meador, Lukas Mühlena, Kevin W. Becker, Jan Schröder, Qing-Zeng Zhu, Julius S. Lipp, Verena B. Heuer, Matthew P. Crump, and Kai-Uwe Hinrichs
Biogeosciences, 17, 317–330, https://doi.org/10.5194/bg-17-317-2020, https://doi.org/10.5194/bg-17-317-2020, 2020
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This study deals with two membrane lipids called BDGTs and PDGTs. Membrane lipids are molecules forming the cell envelope of all organisms. Different organisms produce different lipids thus they can be used to detect the presence of specific organisms in the environment. We analyzed the structure of these new lipids and looked for potential producers. We found that they are likely made by microbes emitting methane below the sediment surface and could be used to track these specific microbes.
Ying Wu, Kun Zhu, Jing Zhang, Moritz Müller, Shan Jiang, Aazani Mujahid, Mohd Fakharuddin Muhamad, and Edwin Sien Aun Sia
Biogeosciences, 16, 4517–4533, https://doi.org/10.5194/bg-16-4517-2019, https://doi.org/10.5194/bg-16-4517-2019, 2019
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Our understanding of terrestrial organic matter (TOM) in tropical peat-draining rivers remains limited, especially in Southeast Asia. We explored the characteristics of TOM via bulk parameters and lignin phenols of sediment in Malaysia. This showed that the most important plant source of the organic matter in these rivers is woody angiosperm C3 plants with limited diagenetic alteration. This slower degradation of TOM may be a link to higher total nitrogen content, especially for the small river.
Caitlyn R. Witkowski, Sylvain Agostini, Ben P. Harvey, Marcel T. J. van der Meer, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 16, 4451–4461, https://doi.org/10.5194/bg-16-4451-2019, https://doi.org/10.5194/bg-16-4451-2019, 2019
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Carbon dioxide concentrations (pCO2) in the atmosphere play an integral role in Earth system dynamics, especially climate. Past climates help us understand future ones, but reconstructing pCO2 over the geologic record remains a challenge. This research demonstrates new approaches for exploring past pCO2 via the carbon isotope fractionation in general algal lipids, which we test over a high CO2 gradient from a naturally occurring CO2 seep.
Yongli Zhou, Patrick Martin, and Moritz Müller
Biogeosciences, 16, 2733–2749, https://doi.org/10.5194/bg-16-2733-2019, https://doi.org/10.5194/bg-16-2733-2019, 2019
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We found that peatlands in coastal Sarawak, Borneo, export extremely humified organic matter, which dominates the riverine organic matter pool and conservatively mixes with seawater, while the freshly produced fraction is low and stable in concentration at all salinities. We estimated that terrigenous fractions, which showed high photolability, still account for 20 % of the coastal dissolved organic carbon pool, implying the importance of peat-derived organic matter in the coastal carbon cycle.
Kristin Doering, Claudia Ehlert, Philippe Martinez, Martin Frank, and Ralph Schneider
Biogeosciences, 16, 2163–2180, https://doi.org/10.5194/bg-16-2163-2019, https://doi.org/10.5194/bg-16-2163-2019, 2019
Alexandra N. Loginova, Sören Thomsen, Marcus Dengler, Jan Lüdke, and Anja Engel
Biogeosciences, 16, 2033–2047, https://doi.org/10.5194/bg-16-2033-2019, https://doi.org/10.5194/bg-16-2033-2019, 2019
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High primary production in the Peruvian upwelling system is followed by rapid heterotrophic utilization of organic matter and supports the formation of one of the most intense oxygen minimum zones (OMZs) in the world. Here, we estimated vertical fluxes of oxygen and dissolved organic matter (DOM) from the surface to the OMZ. Our results suggest that DOM remineralization substantially reduces oxygen concentration in the upper water column and controls the shape of the upper oxycline.
Carolina Cisternas-Novoa, Frédéric A. C. Le Moigne, and Anja Engel
Biogeosciences, 16, 927–947, https://doi.org/10.5194/bg-16-927-2019, https://doi.org/10.5194/bg-16-927-2019, 2019
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We investigate the composition and vertical fluxes of POM in two deep basins of the Baltic Sea (GB: Gotland Basin and LD: Landsort Deep). The two basins showed different O2 regimes resulting from the intrusion of oxygen-rich water from the North Sea that ventilated the deep waters in GB, but not in LD.
In GB, O2 intrusions lead to a high abundance of manganese oxides that aggregate with POM, altering its composition and vertical flux and contributing to a higher POC transfer efficiency in GB.
Marina Zamanillo, Eva Ortega-Retuerta, Sdena Nunes, Pablo Rodríguez-Ros, Manuel Dall'Osto, Marta Estrada, Maria Montserrat Sala, and Rafel Simó
Biogeosciences, 16, 733–749, https://doi.org/10.5194/bg-16-733-2019, https://doi.org/10.5194/bg-16-733-2019, 2019
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Many marine microorganisms produce polysaccharide-rich transparent exopolymer particles (TEPs) for rather unknown reasons but with important consequences for the ocean carbon cycle, sea–air gas exchange and formation of organic aerosols. Here we compare surface–ocean distributions of TEPs and physical, chemical and biological variables along a N–S transect in the Atlantic Ocean. Our data suggest that phytoplankton and not bacteria are the main TEP producers, and solar radiation acts as a sink.
Michael Philben, Sara Butler, Sharon A. Billings, Ronald Benner, Kate A. Edwards, and Susan E. Ziegler
Biogeosciences, 15, 6731–6746, https://doi.org/10.5194/bg-15-6731-2018, https://doi.org/10.5194/bg-15-6731-2018, 2018
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We explored the relationship between chemical composition and the temperature sensitivity of moss decomposition using 959-day lab incubations. Mass loss was low despite the predominance of carbohydrates, indicating the persistence of labile C. Scanning electron microscopy revealed little change in the moss cell-wall structure. These results suggest that the moss cell-wall matrix protects labile C from decomposition, contributing to the globally important stocks of moss-derived C.
Yinghui Wang, Robert G. M. Spencer, David C. Podgorski, Anne M. Kellerman, Harunur Rashid, Phoebe Zito, Wenjie Xiao, Dandan Wei, Yuanhe Yang, and Yunping Xu
Biogeosciences, 15, 6637–6648, https://doi.org/10.5194/bg-15-6637-2018, https://doi.org/10.5194/bg-15-6637-2018, 2018
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With global warming, thawing of permafrost releases dissolved organic matter (DOM) into streams. By analyzing DOM along an alpine stream on the Qinghai–Tibet Plateau, we found DOM was mainly from the active layer, but with deepening of the active layer, the contribution of the deep permafrost layer increased, causing a change in the chemical composition of DOM. From the head- to downstream, DOM is undergoing rapid degradation, but some components are persistent and can be transported downstream.
Sergio Balzano, Julie Lattaud, Laura Villanueva, Sebastiaan W. Rampen, Corina P. D. Brussaard, Judith van Bleijswijk, Nicole Bale, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 5951–5968, https://doi.org/10.5194/bg-15-5951-2018, https://doi.org/10.5194/bg-15-5951-2018, 2018
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We tried to identify the microbes which biosynthesize a class of lipids widespread in seawater, the long chain alkyl diols (LCDs). We could not find any microorganism likely involved in the production of LCDs. The amounts of LCDs found are too high to be produced by living organisms and are likely to be part of the refractory organic matter persisting for long periods in the water column.
Julie Lattaud, Frédérique Kirkels, Francien Peterse, Chantal V. Freymond, Timothy I. Eglinton, Jens Hefter, Gesine Mollenhauer, Sergio Balzano, Laura Villanueva, Marcel T. J. van der Meer, Ellen C. Hopmans, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 4147–4161, https://doi.org/10.5194/bg-15-4147-2018, https://doi.org/10.5194/bg-15-4147-2018, 2018
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Long-chain diols (LCDs) are biomarkers that occur widespread in marine environments and also in lakes and rivers. In this study, we looked at the distribution of LCDs in three river systems (Godavari, Danube, and Rhine) in relation to season, precipitation, and temperature. We found out that the LCDs are likely being produced in calm areas of the river systems and that marine LCDs have a different distribution than riverine LCDs.
Marcel Bliedtner, Imke K. Schäfer, Roland Zech, and Hans von Suchodoletz
Biogeosciences, 15, 3927–3936, https://doi.org/10.5194/bg-15-3927-2018, https://doi.org/10.5194/bg-15-3927-2018, 2018
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In this study, we systematically analyze leaf wax derived n-alkane patterns in eastern Georgia to test their potential for paleoenvironmental reconstructions in the semi-humid to semi-arid central southern Caucasus region. We investigated the influence of vegetation types on the leaf wax signal in modern plants and topsoil material. Our results show distinct and systematic differences in the n-alkane patterns between vegetation types and prove their potential for vegetation reconstructions.
Mathieu Rembauville, Stéphane Blain, Clara Manno, Geraint Tarling, Anu Thompson, George Wolff, and Ian Salter
Biogeosciences, 15, 3071–3084, https://doi.org/10.5194/bg-15-3071-2018, https://doi.org/10.5194/bg-15-3071-2018, 2018
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Sinking phytoplankton from the surface ocean provide the principal energy source to deep-ocean ecosystems. Our aim was to understand how different phytoplankton communities impact the chemical nature of this sinking material. We show certain types of phytoplankton can preferentially export energy-rich storage compounds to the seafloor. Any climate-driven effects on phytoplankton community structure could thus impact remote deep-ocean ecosystems thousands of kilometres beneath the surface.
Xiaocong Wei, Xiangwen Deng, Wenhua Xiang, Pifeng Lei, Shuai Ouyang, Hongfang Wen, and Liang Chen
Biogeosciences, 15, 2991–3002, https://doi.org/10.5194/bg-15-2991-2018, https://doi.org/10.5194/bg-15-2991-2018, 2018
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Karst is a kind of typical calcium-rich environment, which is widely distributed. We measured the Ca2+ content of 41 plant species, as well as soil total Ca2+ and exchange Ca2+. We found out that different plants have different ways to high Ca2+ adaptation. According to the different high Ca2+ adaptation of the 17 dominant species, we divided them into 3 categories: Ca-indifferent plants, high-Ca plants and low-Ca plants. Our results can provide a theoretical basis for vegetation restoration.
Janina G. Stapel, Georg Schwamborn, Lutz Schirrmeister, Brian Horsfield, and Kai Mangelsdorf
Biogeosciences, 15, 1969–1985, https://doi.org/10.5194/bg-15-1969-2018, https://doi.org/10.5194/bg-15-1969-2018, 2018
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Climate warming in the Arctic results in thawing of permafrost deposits. This promotes the accessibility of freeze-locked old organic matter (OM) accumulated during the past. Characterizing OM of different depositional ages, we were able to show that OM from last glacial Yedoma deposits possess the highest potential to provide organic substrates such as acetate for microbial greenhouse gas production and therefore to accelerate the carbon–climate feedback cycle during ongoing global warming.
Changchun Huang, Quanliang Jiang, Ling Yao, Hao Yang, Chen Lin, Tao Huang, A-Xing Zhu, and Yimin Zhang
Biogeosciences, 15, 1827–1841, https://doi.org/10.5194/bg-15-1827-2018, https://doi.org/10.5194/bg-15-1827-2018, 2018
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The latitudinal dependency of POC / PON in ocean and inland water is significant, regulated by trophic state and climate, etc. factors. POC / PON significantly increased from coastal water (6.89 ± 2.38) to open ocean (7.59 ± 4.22) with the increasing rate of 0.0024 / km. The re-examination of the global relationship between, and variations in, POC and PON could be important for the global and regional coupling between the carbon and nitrogen cycles in the ocean and freshwater.
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