Articles | Volume 16, issue 2
https://doi.org/10.5194/bg-16-437-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/bg-16-437-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Sedimentary alkalinity generation and long-term alkalinity development in the Baltic Sea
Baltic Nest Institute, Baltic Sea Centre, Stockholm University, 10691, Stockholm, Sweden
Department of Earth Sciences, Geochemistry, Utrecht University, P.O. Box 80.021, 3508 TA Utrecht, the Netherlands
now at: Soil Chemistry and Chemical Soil Quality, Wageningen University, P.O. Box 47, 6700 AA Wageningen, the Netherlands
Xiaole Sun
Baltic Sea Centre, Stockholm University, 10691, Stockholm, Sweden
Daniel C. Reed
Fisheries & Oceans Canada, Bedford Institute of Oceanography, Dartmouth, NS, Canada
Christoph Humborg
Baltic Sea Centre, Stockholm University, 10691, Stockholm, Sweden
Department of Environmental Science and Analytical Chemistry, Stockholm University, 10691, Stockholm, Sweden
Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland
Caroline P. Slomp
Department of Earth Sciences, Geochemistry, Utrecht University, P.O. Box 80.021, 3508 TA Utrecht, the Netherlands
Bo G. Gustafsson
Baltic Nest Institute, Baltic Sea Centre, Stockholm University, 10691, Stockholm, Sweden
Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland
Related authors
Erik Gustafsson, Bo G. Gustafsson, Martijn Hermans, Christoph Humborg, and Christian Stranne
Geosci. Model Dev., 17, 7157–7179, https://doi.org/10.5194/gmd-17-7157-2024, https://doi.org/10.5194/gmd-17-7157-2024, 2024
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Methane (CH4) cycling in the Baltic Proper is studied through model simulations, enabling a first estimate of key CH4 fluxes. A preliminary budget identifies benthic CH4 release as the dominant source and two main sinks: CH4 oxidation in the water (92 % of sinks) and outgassing to the atmosphere (8 % of sinks). This study addresses CH4 emissions from coastal seas and is a first step toward understanding the relative importance of open-water outgassing compared with local coastal hotspots.
Filippa Fransner, Agneta Fransson, Christoph Humborg, Erik Gustafsson, Letizia Tedesco, Robinson Hordoir, and Jonas Nycander
Biogeosciences, 16, 863–879, https://doi.org/10.5194/bg-16-863-2019, https://doi.org/10.5194/bg-16-863-2019, 2019
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Although rivers carry large amounts of organic material to the oceans, little is known about what fate it meets when it reaches the sea. In this study we are investigating the fate of the carbon in this organic matter by the use of a numerical model in combination with ship measurements from the northern Baltic Sea. Our results suggests that there is substantial remineralization taking place, transforming the organic carbon into CO2, which is released to the atmosphere.
Erik Gustafsson, Christoph Humborg, Göran Björk, Christian Stranne, Leif G. Anderson, Marc C. Geibel, Carl-Magnus Mörth, Marcus Sundbom, Igor P. Semiletov, Brett F. Thornton, and Bo G. Gustafsson
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-115, https://doi.org/10.5194/bg-2017-115, 2017
Preprint withdrawn
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In this study we quantify key carbon cycling processes on the East Siberian Arctic Shelf. A specific aim is to determine the pathways of terrestrial organic carbon (OC) supplied by rivers and coastline erosion – and particularly to what extent degradation of terrestrial OC contributes to air-sea CO2 exchange. We estimate that the shelf is a weak CO2 sink, although this sink is considerably reduced mainly by degradation of eroded OC and to a lesser extent by degradation of riverine OC.
Erik Gustafsson, Bo G. Gustafsson, Martijn Hermans, Christoph Humborg, and Christian Stranne
Geosci. Model Dev., 17, 7157–7179, https://doi.org/10.5194/gmd-17-7157-2024, https://doi.org/10.5194/gmd-17-7157-2024, 2024
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Methane (CH4) cycling in the Baltic Proper is studied through model simulations, enabling a first estimate of key CH4 fluxes. A preliminary budget identifies benthic CH4 release as the dominant source and two main sinks: CH4 oxidation in the water (92 % of sinks) and outgassing to the atmosphere (8 % of sinks). This study addresses CH4 emissions from coastal seas and is a first step toward understanding the relative importance of open-water outgassing compared with local coastal hotspots.
Robin Klomp, Olga M. Żygadłowska, Mike S. M. Jetten, Véronique E. Oldham, Niels A. G. M. van Helmond, Caroline P. Slomp, and Wytze K. Lenstra
EGUsphere, https://doi.org/10.5194/egusphere-2024-1706, https://doi.org/10.5194/egusphere-2024-1706, 2024
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In marine sediments, dissolved Mn is present as either Mn(III) or Mn(II). We apply a reactive transport model to geochemical data for a seasonally anoxic and sulfidic coastal basin to determine the pathways of formation and removal of dissolved Mn(III) in the sediment. We demonstrate a critical role for reactions with Fe(II) and show evidence for substantial benthic release of dissolved Mn(III). Given the mobility of Mn(III), these findings have important implications for marine Mn cycling.
Julia Muchowski, Martin Jakobsson, Lars Umlauf, Lars Arneborg, Bo Gustafsson, Peter Holtermann, Christoph Humborg, and Christian Stranne
Ocean Sci., 19, 1809–1825, https://doi.org/10.5194/os-19-1809-2023, https://doi.org/10.5194/os-19-1809-2023, 2023
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We show observational data of highly increased mixing and vertical salt flux rates in a sparsely sampled region of the northern Baltic Sea. Co-located acoustic observations complement our in situ measurements and visualize turbulent mixing with high spatial resolution. The observed mixing is generally not resolved in numerical models of the area but likely impacts the exchange of water between the adjacent basins as well as nutrient and oxygen conditions in the Bothnian Sea.
Wout Krijgsman, Iuliana Vasiliev, Anouk Beniest, Timothy Lyons, Johanna Lofi, Gabor Tari, Caroline P. Slomp, Namik Cagatay, Maria Triantaphyllou, Rachel Flecker, Dan Palcu, Cecilia McHugh, Helge Arz, Pierre Henry, Karen Lloyd, Gunay Cifci, Özgür Sipahioglu, Dimitris Sakellariou, and the BlackGate workshop participants
Sci. Dril., 31, 93–110, https://doi.org/10.5194/sd-31-93-2022, https://doi.org/10.5194/sd-31-93-2022, 2022
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BlackGate seeks to MSP drill a transect to study the impact of dramatic hydrologic change in Mediterranean–Black Sea connectivity by recovering the Messinian to Holocene (~ 7 Myr) sedimentary sequence in the North Aegean, Marmara, and Black seas. These archives will reveal hydrographic, biotic, and climatic transitions studied by a broad scientific community spanning the stratigraphic, tectonic, biogeochemical, and microbiological evolution of Earth’s most recent saline and anoxic giant.
Eva Ehrnsten, Oleg Pavlovitch Savchuk, and Bo Gustav Gustafsson
Biogeosciences, 19, 3337–3367, https://doi.org/10.5194/bg-19-3337-2022, https://doi.org/10.5194/bg-19-3337-2022, 2022
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We studied the effects of benthic fauna, animals living on or in the seafloor, on the biogeochemical cycles of carbon, nitrogen and phosphorus using a model of the Baltic Sea ecosystem. By eating and excreting, the animals transform a large part of organic matter sinking to the seafloor into inorganic forms, which fuel plankton blooms. Simultaneously, when they move around (bioturbate), phosphorus is bound in the sediments. This reduces nitrogen-fixing plankton blooms and oxygen depletion.
Karol Kuliński, Gregor Rehder, Eero Asmala, Alena Bartosova, Jacob Carstensen, Bo Gustafsson, Per O. J. Hall, Christoph Humborg, Tom Jilbert, Klaus Jürgens, H. E. Markus Meier, Bärbel Müller-Karulis, Michael Naumann, Jørgen E. Olesen, Oleg Savchuk, Andreas Schramm, Caroline P. Slomp, Mikhail Sofiev, Anna Sobek, Beata Szymczycha, and Emma Undeman
Earth Syst. Dynam., 13, 633–685, https://doi.org/10.5194/esd-13-633-2022, https://doi.org/10.5194/esd-13-633-2022, 2022
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The paper covers the aspects related to changes in carbon, nitrogen, and phosphorus (C, N, P) external loads; their transformations in the coastal zone; changes in organic matter production (eutrophication) and remineralization (oxygen availability); and the role of sediments in burial and turnover of C, N, and P. Furthermore, this paper also focuses on changes in the marine CO2 system, the structure of the microbial community, and the role of contaminants for biogeochemical processes.
Tanya J. R. Lippmann, Michiel H. in 't Zandt, Nathalie N. L. Van der Putten, Freek S. Busschers, Marc P. Hijma, Pieter van der Velden, Tim de Groot, Zicarlo van Aalderen, Ove H. Meisel, Caroline P. Slomp, Helge Niemann, Mike S. M. Jetten, Han A. J. Dolman, and Cornelia U. Welte
Biogeosciences, 18, 5491–5511, https://doi.org/10.5194/bg-18-5491-2021, https://doi.org/10.5194/bg-18-5491-2021, 2021
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This paper is a step towards understanding the basal peat ecosystem beneath the North Sea. Plant remains followed parallel sequences. Methane concentrations were low with local exceptions, with the source likely being trapped pockets of millennia-old methane. Microbial community structure indicated the absence of a biofilter and was diverse across sites. Large carbon stores in the presence of methanogens and in the absence of methanotrophs have the potential to be metabolized into methane.
Martijn Hermans, Nils Risgaard-Petersen, Filip J. R. Meysman, and Caroline P. Slomp
Biogeosciences, 17, 5919–5938, https://doi.org/10.5194/bg-17-5919-2020, https://doi.org/10.5194/bg-17-5919-2020, 2020
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This paper demonstrates that the recently discovered cable bacteria are capable of using a mineral, known as siderite, as a source for the formation of iron oxides. This work also demonstrates that the activity of cable bacteria can lead to a distinct subsurface layer in the sediment that can be used as a marker for their activity.
Olivier Sulpis, Siv K. Lauvset, and Mathilde Hagens
Ocean Sci., 16, 847–862, https://doi.org/10.5194/os-16-847-2020, https://doi.org/10.5194/os-16-847-2020, 2020
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As direct measurements of seawater carbonate system variables, such as pH, are difficult to obtain, scientists use equilibrium constants to compute them from known variables. Using a compilation of in situ data, we show that the set of equilibrium constants preferred by the community is not consistent with measurements in cold, polar waters, where human-made ocean acidification is spreading rapidly. Closing knowledge gaps regarding seawater carbon chemistry in polar regions should be a priority.
Niels A. G. M. van Helmond, Elizabeth K. Robertson, Daniel J. Conley, Martijn Hermans, Christoph Humborg, L. Joëlle Kubeneck, Wytze K. Lenstra, and Caroline P. Slomp
Biogeosciences, 17, 2745–2766, https://doi.org/10.5194/bg-17-2745-2020, https://doi.org/10.5194/bg-17-2745-2020, 2020
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We studied the removal of phosphorus (P) and nitrogen (N) in the eutrophic Stockholm archipelago (SA). High sedimentation rates and sediment P contents lead to high P burial. Benthic denitrification is the primary nitrate-reducing pathway. Together, these mechanisms limit P and N transport to the open Baltic Sea. We expect that further nutrient load reduction will contribute to recovery of the SA from low-oxygen conditions and that the sediments will continue to remove part of the P and N loads.
Julien Richirt, Bettina Riedel, Aurélia Mouret, Magali Schweizer, Dewi Langlet, Dorina Seitaj, Filip J. R. Meysman, Caroline P. Slomp, and Frans J. Jorissen
Biogeosciences, 17, 1415–1435, https://doi.org/10.5194/bg-17-1415-2020, https://doi.org/10.5194/bg-17-1415-2020, 2020
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The paper presents the response of benthic foraminiferal communities to seasonal absence of oxygen coupled with the presence of hydrogen sulfide, considered very harmful for several living organisms.
Our results suggest that the foraminiferal community mainly responds as a function of the duration of the adverse conditions.
This knowledge is especially useful to better understand the ecology of benthic foraminifera but also in the context of palaeoceanographic interpretations.
Martin Jakobsson, Christian Stranne, Matt O'Regan, Sarah L. Greenwood, Bo Gustafsson, Christoph Humborg, and Elizabeth Weidner
Ocean Sci., 15, 905–924, https://doi.org/10.5194/os-15-905-2019, https://doi.org/10.5194/os-15-905-2019, 2019
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The bottom topography of the Baltic Sea is analysed using the digital depth model from the European Marine Observation and Data Network (EMODnet) published in 2018. Analyses include depth distribution vs. area and seafloor depth variation on a kilometre scale. The limits for the Baltic Sea and analysed sub-basins are from HELCOM. EMODnet is compared with the previously most widely used depth model and the area of deep water exchange between the Bothnian Sea and the Northern Baltic Proper.
Filippa Fransner, Agneta Fransson, Christoph Humborg, Erik Gustafsson, Letizia Tedesco, Robinson Hordoir, and Jonas Nycander
Biogeosciences, 16, 863–879, https://doi.org/10.5194/bg-16-863-2019, https://doi.org/10.5194/bg-16-863-2019, 2019
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Although rivers carry large amounts of organic material to the oceans, little is known about what fate it meets when it reaches the sea. In this study we are investigating the fate of the carbon in this organic matter by the use of a numerical model in combination with ship measurements from the northern Baltic Sea. Our results suggests that there is substantial remineralization taking place, transforming the organic carbon into CO2, which is released to the atmosphere.
Wytze K. Lenstra, Matthias Egger, Niels A. G. M. van Helmond, Emma Kritzberg, Daniel J. Conley, and Caroline P. Slomp
Biogeosciences, 15, 6979–6996, https://doi.org/10.5194/bg-15-6979-2018, https://doi.org/10.5194/bg-15-6979-2018, 2018
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We show that burial rates of phosphorus (P) in an estuary in the northern Baltic Sea are very high. We demonstrate that at high sedimentation rates, P retention in the sediment is related to the formation of vivianite. With a reactive transport model, we assess the sensitivity of sedimentary vivianite formation. We suggest that enrichments of iron and P in the sediment are linked to periods of enhanced riverine input of Fe, which subsequently strongly enhances P burial in coastal sediments.
Nikki Dijkstra, Mathilde Hagens, Matthias Egger, and Caroline P. Slomp
Biogeosciences, 15, 861–883, https://doi.org/10.5194/bg-15-861-2018, https://doi.org/10.5194/bg-15-861-2018, 2018
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We show that post-depositional formation of iron(II) phosphate as vivianite strongly alters the phosphorus record in sediments of the Bornholm Basin (Baltic Sea). These minerals began to precipitate in the lake sediments just after the last lake–marine transition ~ 7.5 kyr BP, migrated downwards and are now a stable feature. Formation of vivianite may affect sedimentary phosphorus records in other systems as well. This should be considered when using such records to reconstruct past environments.
Volker Brüchert, Lisa Bröder, Joanna E. Sawicka, Tommaso Tesi, Samantha P. Joye, Xiaole Sun, Igor P. Semiletov, and Vladimir A. Samarkin
Biogeosciences, 15, 471–490, https://doi.org/10.5194/bg-15-471-2018, https://doi.org/10.5194/bg-15-471-2018, 2018
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We determined the aerobic and anaerobic degradation rates of land- and marine-derived organic material in East Siberian shelf sediment. Marine plankton-derived organic carbon was the main source for the oxic dissolved carbon dioxide production, whereas terrestrial organic material significantly contributed to the production of carbon dioxide under anoxic conditions. Our direct degradation rate measurements provide new constraints for the present-day Arctic marine carbon budget.
Jassin Petersen, Christine Barras, Antoine Bézos, Carole La, Lennart J. de Nooijer, Filip J. R. Meysman, Aurélia Mouret, Caroline P. Slomp, and Frans J. Jorissen
Biogeosciences, 15, 331–348, https://doi.org/10.5194/bg-15-331-2018, https://doi.org/10.5194/bg-15-331-2018, 2018
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In Lake Grevelingen, a coastal ecosystem, foraminifera experience important temporal variations in oxygen concentration and in pore water manganese. The high resolution of LA-ICP-MS allows us to analyse the chambers of foraminiferal shells separately and to obtain signals from a series of calcification events. We estimate the variability in Mn/Ca observed within single shells due to biomineralization and show that a substantial part of the signal is related to environmental variability.
Ulrich Kotthoff, Jeroen Groeneveld, Jeanine L. Ash, Anne-Sophie Fanget, Nadine Quintana Krupinski, Odile Peyron, Anna Stepanova, Jonathan Warnock, Niels A. G. M. Van Helmond, Benjamin H. Passey, Ole Rønø Clausen, Ole Bennike, Elinor Andrén, Wojciech Granoszewski, Thomas Andrén, Helena L. Filipsson, Marit-Solveig Seidenkrantz, Caroline P. Slomp, and Thorsten Bauersachs
Biogeosciences, 14, 5607–5632, https://doi.org/10.5194/bg-14-5607-2017, https://doi.org/10.5194/bg-14-5607-2017, 2017
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We present reconstructions of paleotemperature, paleosalinity, and paleoecology from the Little Belt (Site M0059) over the past ~ 8000 years and evaluate the applicability of numerous proxies. Conditions were lacustrine until ~ 7400 cal yr BP. A transition to brackish–marine conditions then occurred within ~ 200 years. Salinity proxies rarely allowed quantitative estimates but revealed congruent results, while quantitative temperature reconstructions differed depending on the proxies used.
Tommaso Tesi, Marc C. Geibel, Christof Pearce, Elena Panova, Jorien E. Vonk, Emma Karlsson, Joan A. Salvado, Martin Kruså, Lisa Bröder, Christoph Humborg, Igor Semiletov, and Örjan Gustafsson
Ocean Sci., 13, 735–748, https://doi.org/10.5194/os-13-735-2017, https://doi.org/10.5194/os-13-735-2017, 2017
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Recent Arctic studies suggest that sea-ice decline and permafrost thawing will affect the phytoplankton in the Arctic Ocean. However, in what way the plankton composition will change as the warming proceeds remains elusive. Here we show that the carbon composition of plankton might change as a function of the enhanced terrestrial organic carbon supply and progressive sea-ice thawing.
Erik Gustafsson, Christoph Humborg, Göran Björk, Christian Stranne, Leif G. Anderson, Marc C. Geibel, Carl-Magnus Mörth, Marcus Sundbom, Igor P. Semiletov, Brett F. Thornton, and Bo G. Gustafsson
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-115, https://doi.org/10.5194/bg-2017-115, 2017
Preprint withdrawn
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In this study we quantify key carbon cycling processes on the East Siberian Arctic Shelf. A specific aim is to determine the pathways of terrestrial organic carbon (OC) supplied by rivers and coastline erosion – and particularly to what extent degradation of terrestrial OC contributes to air-sea CO2 exchange. We estimate that the shelf is a weak CO2 sink, although this sink is considerably reduced mainly by degradation of eroded OC and to a lesser extent by degradation of riverine OC.
Matthias Egger, Peter Kraal, Tom Jilbert, Fatimah Sulu-Gambari, Célia J. Sapart, Thomas Röckmann, and Caroline P. Slomp
Biogeosciences, 13, 5333–5355, https://doi.org/10.5194/bg-13-5333-2016, https://doi.org/10.5194/bg-13-5333-2016, 2016
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By combining detailed geochemical analyses with diagenetic modeling, we provide new insights into how methane dynamics may strongly overprint burial records of iron, sulfur and phosphorus in marine systems subject to changes in organic matter loading or water column salinity. A better understanding of these processes will improve our ability to read ancient sediment records and thus to predict the potential consequences of global warming and human-enhanced inputs of nutrients to the ocean.
C. Lenz, T. Jilbert, D.J. Conley, M. Wolthers, and C.P. Slomp
Biogeosciences, 12, 4875–4894, https://doi.org/10.5194/bg-12-4875-2015, https://doi.org/10.5194/bg-12-4875-2015, 2015
M. Hagens, C. P. Slomp, F. J. R. Meysman, D. Seitaj, J. Harlay, A. V. Borges, and J. J. Middelburg
Biogeosciences, 12, 1561–1583, https://doi.org/10.5194/bg-12-1561-2015, https://doi.org/10.5194/bg-12-1561-2015, 2015
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This study looks at the combined impacts of hypoxia and acidification, two major environmental stressors affecting coastal systems, in a seasonally stratified basin. Here, the surface water experiences less seasonality in pH than the bottom water despite higher process rates. This is due to a substantial reduction in the acid-base buffering capacity of the bottom water as it turns hypoxic in summer. This highlights the crucial role of the buffering capacity as a modulating factor in pH dynamics.
A. Sluijs, L. van Roij, G. J. Harrington, S. Schouten, J. A. Sessa, L. J. LeVay, G.-J. Reichart, and C. P. Slomp
Clim. Past, 10, 1421–1439, https://doi.org/10.5194/cp-10-1421-2014, https://doi.org/10.5194/cp-10-1421-2014, 2014
I. Ruvalcaba Baroni, R. P. M. Topper, N. A. G. M. van Helmond, H. Brinkhuis, and C. P. Slomp
Biogeosciences, 11, 977–993, https://doi.org/10.5194/bg-11-977-2014, https://doi.org/10.5194/bg-11-977-2014, 2014
A. F. Bouwman, M. F. P. Bierkens, J. Griffioen, M. M. Hefting, J. J. Middelburg, H. Middelkoop, and C. P. Slomp
Biogeosciences, 10, 1–22, https://doi.org/10.5194/bg-10-1-2013, https://doi.org/10.5194/bg-10-1-2013, 2013
Related subject area
Biogeochemistry: Coastal Ocean
Temperature-enhanced effects of iron on Southern Ocean phytoplankton
Riverine nutrient impact on global ocean nitrogen cycle feedbacks and marine primary production in an Earth system model
The Northeast Greenland Shelf as a potential late-summer CO2 source to the atmosphere
Technical note: Ocean Alkalinity Enhancement Pelagic Impact Intercomparison Project (OAEPIIP)
Estimates of carbon sequestration potential in an expanding Arctic fjord (Hornsund, Svalbard) affected by dark plumes of glacial meltwater
An assessment of ocean alkalinity enhancement using aqueous hydroxides: kinetics, efficiency, and precipitation thresholds
High metabolic zinc demand within native Amundsen and Ross Sea phytoplankton communities determined by stable isotope uptake rate measurements
Dissolved nitric oxide in the lower Elbe Estuary and the Port of Hamburg area
Variable contribution of wastewater treatment plant effluents to downstream nitrous oxide concentrations and emissions
Responses of microbial metabolic rates to non-equilibrated silicate vs calcium-based ocean alkalinity enhancement
Distribution of nutrients and dissolved organic matter in a eutrophic equatorial estuary: the Johor River and the East Johor Strait
Investigating the effect of silicate- and calcium-based ocean alkalinity enhancement on diatom silicification
Ocean alkalinity enhancement using sodium carbonate salts does not lead to measurable changes in Fe dynamics in a mesocosm experiment
Quantification and mitigation of bottom-trawling impacts on sedimentary organic carbon stocks in the North Sea
Influence of ocean alkalinity enhancement with olivine or steel slag on a coastal plankton community in Tasmania
Multi-model comparison of trends and controls of near-bed oxygen concentration on the northwest European continental shelf under climate change
Picoplanktonic methane production in eutrophic surface waters
Vertical mixing alleviates autumnal oxygen deficiency in the central North Sea
Hypoxia also occurs in small highly turbid estuaries: the example of the Charente (Bay of Biscay)
Assessing the impacts of simulated Ocean Alkalinity Enhancement on viability and growth of near-shore species of phytoplankton
Seasonality and response of ocean acidification and hypoxia to major environmental anomalies in the southern Salish Sea, North America (2014–2018)
The influence of zooplankton and oxygen on the particulate organic carbon flux in the Benguela Upwelling System
Oceanographic processes driving low-oxygen conditions inside Patagonian fjords
Above- and belowground plant mercury dynamics in a salt marsh estuary in Massachusetts, USA
Reviews and syntheses: Biological Indicators of Oxygen Stress in Water Breathing Animals
Variability and drivers of carbonate chemistry at shellfish aquaculture sites in the Salish Sea, British Columbia
Unusual Hemiaulus bloom influences ocean productivity in Northeastern US Shelf waters
Insights into carbonate environmental conditions in the Chukchi Sea
UAV approaches for improved mapping of vegetation cover and estimation of carbon storage of small saltmarshes: examples from Loch Fleet, northeast Scotland
Iron “ore” nothing: benthic iron fluxes from the oxygen-deficient Santa Barbara Basin enhance phytoplankton productivity in surface waters
Marine anoxia initiates giant sulfur-oxidizing bacterial mat proliferation and associated changes in benthic nitrogen, sulfur, and iron cycling in the Santa Barbara Basin, California Borderland
Uncertainty in the evolution of northwestern North Atlantic circulation leads to diverging biogeochemical projections
The additionality problem of ocean alkalinity enhancement
Short-term variation in pH in seawaters around coastal areas of Japan: characteristics and forcings
Revisiting the applicability and constraints of molybdenum- and uranium-based paleo redox proxies: comparing two contrasting sill fjords
Influence of a small submarine canyon on biogenic matter export flux in the lower St. Lawrence Estuary, eastern Canada
Single-celled bioturbators: benthic foraminifera mediate oxygen penetration and prokaryotic diversity in intertidal sediment
Assessing impacts of coastal warming, acidification, and deoxygenation on Pacific oyster (Crassostrea gigas) farming: a case study in the Hinase area, Okayama Prefecture, and Shizugawa Bay, Miyagi Prefecture, Japan
Multiple nitrogen sources for primary production inferred from δ13C and δ15N in the southern Sea of Japan
Influence of manganese cycling on alkalinity in the redox stratified water column of Chesapeake Bay
Estuarine flocculation dynamics of organic carbon and metals from boreal acid sulfate soils
Drivers of particle sinking velocities in the Peruvian upwelling system
Impacts and uncertainties of climate-induced changes in watershed inputs on estuarine hypoxia
Considerations for hypothetical carbon dioxide removal via alkalinity addition in the Amazon River watershed
High metabolism and periodic hypoxia associated with drifting macrophyte detritus in the shallow subtidal Baltic Sea
Production and accumulation of reef framework by calcifying corals and macroalgae on a remote Indian Ocean cay
Zooplankton community succession and trophic links during a mesocosm experiment in the coastal upwelling off Callao Bay (Peru)
Temporal and spatial evolution of bottom-water hypoxia in the St Lawrence estuarine system
Significant nutrient consumption in the dark subsurface layer during a diatom bloom: a case study on Funka Bay, Hokkaido, Japan
Contrasts in dissolved, particulate, and sedimentary organic carbon from the Kolyma River to the East Siberian Shelf
Charlotte Eich, Mathijs van Manen, J. Scott P. McCain, Loay J. Jabre, Willem H. van de Poll, Jinyoung Jung, Sven B. E. H. Pont, Hung-An Tian, Indah Ardiningsih, Gert-Jan Reichart, Erin M. Bertrand, Corina P. D. Brussaard, and Rob Middag
Biogeosciences, 21, 4637–4663, https://doi.org/10.5194/bg-21-4637-2024, https://doi.org/10.5194/bg-21-4637-2024, 2024
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Phytoplankton growth in the Southern Ocean (SO) is often limited by low iron (Fe) concentrations. Sea surface warming impacts Fe availability and can affect phytoplankton growth. We used shipboard Fe clean incubations to test how changes in Fe and temperature affect SO phytoplankton. Their abundances usually increased with Fe addition and temperature increase, with Fe being the major factor. These findings imply potential shifts in ecosystem structure, impacting food webs and elemental cycling.
Miriam Tivig, David P. Keller, and Andreas Oschlies
Biogeosciences, 21, 4469–4493, https://doi.org/10.5194/bg-21-4469-2024, https://doi.org/10.5194/bg-21-4469-2024, 2024
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Marine biological production is highly dependent on the availability of nitrogen and phosphorus. Rivers are the main source of phosphorus to the oceans but poorly represented in global model oceans. We include dissolved nitrogen and phosphorus from river export in a global model ocean and find that the addition of riverine phosphorus affects marine biology on millennial timescales more than riverine nitrogen alone. Globally, riverine phosphorus input increases primary production rates.
Esdoorn Willcox, Marcos Lemes, Thomas Juul-Pedersen, Mikael Kristian Sejr, Johnna Marchiano Holding, and Søren Rysgaard
Biogeosciences, 21, 4037–4050, https://doi.org/10.5194/bg-21-4037-2024, https://doi.org/10.5194/bg-21-4037-2024, 2024
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In this work, we measured the chemistry of seawater from samples obtained from different depths and locations off the east coast of the Northeast Greenland National Park to determine what is influencing concentrations of dissolved CO2. Historically, the region has always been thought to take up CO2 from the atmosphere, but we show that it is possible for the region to become a source in late summer. We discuss the variables that may be related to such changes.
Lennart Thomas Bach, Aaron James Ferderer, Julie LaRoche, and Kai Georg Schulz
Biogeosciences, 21, 3665–3676, https://doi.org/10.5194/bg-21-3665-2024, https://doi.org/10.5194/bg-21-3665-2024, 2024
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Ocean alkalinity enhancement (OAE) is an emerging marine CO2 removal method, but its environmental effects are insufficiently understood. The OAE Pelagic Impact Intercomparison Project (OAEPIIP) provides funding for a standardized and globally replicated microcosm experiment to study the effects of OAE on plankton communities. Here, we provide a detailed manual for the OAEPIIP experiment. We expect OAEPIIP to help build scientific consensus on the effects of OAE on plankton.
Marlena Szeligowska, Déborah Benkort, Anna Przyborska, Mateusz Moskalik, Bernabé Moreno, Emilia Trudnowska, and Katarzyna Błachowiak-Samołyk
Biogeosciences, 21, 3617–3639, https://doi.org/10.5194/bg-21-3617-2024, https://doi.org/10.5194/bg-21-3617-2024, 2024
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The European Arctic is experiencing rapid regional warming, causing glaciers that terminate in the sea to retreat onto land. Due to this process, the area of a well-studied fjord, Hornsund, has increased by around 100 km2 (40%) since 1976. Combining satellite and in situ data with a mathematical model, we estimated that, despite some negative consequences of glacial meltwater release, such emerging coastal waters could mitigate climate change by increasing carbon uptake and storage by sediments.
Mallory C. Ringham, Nathan Hirtle, Cody Shaw, Xi Lu, Julian Herndon, Brendan R. Carter, and Matthew D. Eisaman
Biogeosciences, 21, 3551–3570, https://doi.org/10.5194/bg-21-3551-2024, https://doi.org/10.5194/bg-21-3551-2024, 2024
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Ocean alkalinity enhancement leverages the large surface area and carbon storage capacity of the oceans to store atmospheric CO2 as dissolved bicarbonate. We monitored CO2 uptake in seawater treated with NaOH to establish operational boundaries for carbon removal experiments. Results show that CO2 equilibration occurred on the order of weeks to months, was consistent with values expected from equilibration calculations, and was limited by mineral precipitation at high pH and CaCO3 saturation.
Riss M. Kell, Rebecca J. Chmiel, Deepa Rao, Dawn M. Moran, Matthew R. McIlvin, Tristan J. Horner, Nicole L. Schanke, Robert B. Dunbar, Giacomo R. DiTullio, and Mak A. Saito
EGUsphere, https://doi.org/10.5194/egusphere-2024-2085, https://doi.org/10.5194/egusphere-2024-2085, 2024
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Southern Ocean phytoplankton play a pivotal role in regulating the uptake and sequestration of carbon dioxide from the atmosphere. This study describes a new stable zinc isotope uptake rate measurement method used to quantify zinc and cadmium uptake rates within native Southern Ocean phytoplankton communities. This data can better inform biogeochemical model predictions of primary production, carbon export, and atmospheric carbon dioxide flux.
Riel Carlo O. Ingeniero, Gesa Schulz, and Hermann W. Bange
Biogeosciences, 21, 3425–3440, https://doi.org/10.5194/bg-21-3425-2024, https://doi.org/10.5194/bg-21-3425-2024, 2024
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Our research is the first to measure dissolved NO concentrations in temperate estuarine waters, providing insights into its distribution under varying conditions and enhancing our understanding of its production processes. Dissolved NO was supersaturated in the Elbe Estuary, indicating that it is a source of atmospheric NO. The observed distribution of dissolved NO most likely resulted from nitrification.
Weiyi Tang, Jeff Talbott, Timothy Jones, and Bess B. Ward
Biogeosciences, 21, 3239–3250, https://doi.org/10.5194/bg-21-3239-2024, https://doi.org/10.5194/bg-21-3239-2024, 2024
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Wastewater treatment plants (WWTPs) are known to be hotspots of greenhouse gas emissions. However, the impact of WWTPs on the emission of the greenhouse gas N2O in downstream aquatic environments is less constrained. We found spatially and temporally variable but overall higher N2O concentrations and fluxes in waters downstream of WWTPs, pointing to the need for efficient N2O removal in addition to the treatment of nitrogen in WWTPs.
Laura Marin-Samper, Javier Arístegui, Nauzet Hernández-Hernández, and Ulf Riebesell
EGUsphere, https://doi.org/10.5194/egusphere-2024-1776, https://doi.org/10.5194/egusphere-2024-1776, 2024
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This study exposed a natural community to two non-CO2 equilibrated ocean alkalinity enhancement (OAE) deployments using different minerals. Adding alkalinity in this manner decreases dissolved CO2, essential for photosynthesis. While photosynthesis was not suppressed, bloom formation was delayed, potentially impacting marine food webs. The study emphasizes the need for further research on OAE without prior equilibration and its ecological implications
Amanda Y. L. Cheong, Kogila Vani Annammala, Ee Ling Yong, Yongli Zhou, Robert S. Nichols, and Patrick Martin
Biogeosciences, 21, 2955–2971, https://doi.org/10.5194/bg-21-2955-2024, https://doi.org/10.5194/bg-21-2955-2024, 2024
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We measured nutrients and dissolved organic matter for 1 year in a eutrophic tropical estuary to understand their sources and cycling. Our data show that the dissolved organic matter originates partly from land and partly from microbial processes in the water. Internal recycling is likely important for maintaining high nutrient concentrations, and we found that there is often excess nitrogen compared to silicon and phosphorus. Our data help to explain how eutrophication persists in this system.
Aaron Ferderer, Kai G. Schulz, Ulf Riebesell, Kirralee G. Baker, Zanna Chase, and Lennart T. Bach
Biogeosciences, 21, 2777–2794, https://doi.org/10.5194/bg-21-2777-2024, https://doi.org/10.5194/bg-21-2777-2024, 2024
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Ocean alkalinity enhancement (OAE) is a promising method of atmospheric carbon removal; however, its ecological impacts remain largely unknown. We assessed the effects of simulated silicate- and calcium-based mineral OAE on diatom silicification. We found that increased silicate concentrations from silicate-based OAE increased diatom silicification. In contrast, the enhancement of alkalinity had no effect on community silicification and minimal effects on the silicification of different genera.
David González-Santana, María Segovia, Melchor González-Dávila, Librada Ramírez, Aridane G. González, Leonardo J. Pozzo-Pirotta, Veronica Arnone, Victor Vázquez, Ulf Riebesell, and J. Magdalena Santana-Casiano
Biogeosciences, 21, 2705–2715, https://doi.org/10.5194/bg-21-2705-2024, https://doi.org/10.5194/bg-21-2705-2024, 2024
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In a recent experiment off the coast of Gran Canaria (Spain), scientists explored a method called ocean alkalinization enhancement (OAE), where carbonate minerals were added to seawater. This process changed the levels of certain ions in the water, affecting its pH and buffering capacity. The researchers were particularly interested in how this could impact the levels of essential trace metals in the water.
Lucas Porz, Wenyan Zhang, Nils Christiansen, Jan Kossack, Ute Daewel, and Corinna Schrum
Biogeosciences, 21, 2547–2570, https://doi.org/10.5194/bg-21-2547-2024, https://doi.org/10.5194/bg-21-2547-2024, 2024
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Seafloor sediments store a large amount of carbon, helping to naturally regulate Earth's climate. If disturbed, some sediment particles can turn into CO2, but this effect is not well understood. Using computer simulations, we found that bottom-contacting fishing gears release about 1 million tons of CO2 per year in the North Sea, one of the most heavily fished regions globally. We show how protecting certain areas could reduce these emissions while also benefitting seafloor-living animals.
Jiaying A. Guo, Robert F. Strzepek, Kerrie M. Swadling, Ashley T. Townsend, and Lennart T. Bach
Biogeosciences, 21, 2335–2354, https://doi.org/10.5194/bg-21-2335-2024, https://doi.org/10.5194/bg-21-2335-2024, 2024
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Ocean alkalinity enhancement aims to increase atmospheric CO2 sequestration by adding alkaline materials to the ocean. We assessed the environmental effects of olivine and steel slag powder on coastal plankton. Overall, slag is more efficient than olivine in releasing total alkalinity and, thus, in its ability to sequester CO2. Slag also had less environmental effect on the enclosed plankton communities when considering its higher CO2 removal potential based on this 3-week experiment.
Giovanni Galli, Sarah Wakelin, James Harle, Jason Holt, and Yuri Artioli
Biogeosciences, 21, 2143–2158, https://doi.org/10.5194/bg-21-2143-2024, https://doi.org/10.5194/bg-21-2143-2024, 2024
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This work shows that, under a high-emission scenario, oxygen concentration in deep water of parts of the North Sea and Celtic Sea can become critically low (hypoxia) towards the end of this century. The extent and frequency of hypoxia depends on the intensity of climate change projected by different climate models. This is the result of a complex combination of factors like warming, increase in stratification, changes in the currents and changes in biological processes.
Sandy E. Tenorio and Laura Farías
Biogeosciences, 21, 2029–2050, https://doi.org/10.5194/bg-21-2029-2024, https://doi.org/10.5194/bg-21-2029-2024, 2024
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Time series studies show that CH4 is highly dynamic on the coastal ocean surface and planktonic communities are linked to CH4 accumulation, as found in coastal upwelling off Chile. We have identified the crucial role of picoplankton (> 3 µm) in CH4 recycling, especially with the addition of methylated substrates (trimethylamine and methylphosphonic acid) during upwelling and non-upwelling periods. These insights improve understanding of surface ocean CH4 recycling, aiding CH4 emission estimates.
Charlotte A. J. Williams, Tom Hull, Jan Kaiser, Claire Mahaffey, Naomi Greenwood, Matthew Toberman, and Matthew R. Palmer
Biogeosciences, 21, 1961–1971, https://doi.org/10.5194/bg-21-1961-2024, https://doi.org/10.5194/bg-21-1961-2024, 2024
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Oxygen (O2) is a key indicator of ocean health. The risk of O2 loss in the productive coastal/continental slope regions is increasing. Autonomous underwater vehicles equipped with O2 optodes provide lots of data but have problems resolving strong vertical O2 changes. Here we show how to overcome this and calculate how much O2 is supplied to the low-O2 bottom waters via mixing. Bursts in mixing supply nearly all of the O2 to bottom waters in autumn, stopping them reaching ecologically low levels.
Sabine Schmidt and Ibrahima Iris Diallo
Biogeosciences, 21, 1785–1800, https://doi.org/10.5194/bg-21-1785-2024, https://doi.org/10.5194/bg-21-1785-2024, 2024
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Along the French coast facing the Bay of Biscay, the large Gironde and Loire estuaries suffer from hypoxia. This prompted a study of the small Charente estuary located between them. This work reveals a minimum oxygen zone in the Charente estuary, which extends for about 25 km. Temperature is the main factor controlling the hypoxia. This calls for the monitoring of small turbid macrotidal estuaries that are vulnerable to hypoxia, a risk expected to increase with global warming.
Jessica L. Oberlander, Mackenzie E. Burke, Cat A. London, and Hugh L. MacIntyre
EGUsphere, https://doi.org/10.5194/egusphere-2024-971, https://doi.org/10.5194/egusphere-2024-971, 2024
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OAE is a promising negative emission technology that could restore the oceanic pH and carbonate system to a pre-industrial state. To our knowledge, this paper is the first to assess the potential impact of OAE on phytoplankton through an analysis of prior studies and the effects of simulated OAE on photosynthetic competence. Our findings suggest that there may be little if any significant impact on most phytoplankton studied to date if OAE is conducted in well-flushed, near-shore environments.
Simone R. Alin, Jan A. Newton, Richard A. Feely, Samantha Siedlecki, and Dana Greeley
Biogeosciences, 21, 1639–1673, https://doi.org/10.5194/bg-21-1639-2024, https://doi.org/10.5194/bg-21-1639-2024, 2024
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We provide a new multi-stressor data product that allows us to characterize the seasonality of temperature, O2, and CO2 in the southern Salish Sea and delivers insights into the impacts of major marine heatwave and precipitation anomalies on regional ocean acidification and hypoxia. We also describe the present-day frequencies of temperature, O2, and ocean acidification conditions that cross thresholds of sensitive regional species that are economically or ecologically important.
Luisa Chiara Meiritz, Tim Rixen, Anja K. van der Plas, Tarron Lamont, and Niko Lahajnar
EGUsphere, https://doi.org/10.5194/egusphere-2024-700, https://doi.org/10.5194/egusphere-2024-700, 2024
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The transport of particles through the water column and their subsequent burial on the seafloor is an important process for carbon storage and the mediation of carbon dioxide in the oceans. Our results from the Benguela Upwelling System distinguish between the northern and southern parts of the study area and between passive (gravitational) and active (zooplankton) transport processes. The decomposition of organic matter is doubtlessly an important factor for the size of oxygen minimum zones.
Pamela Linford, Iván Pérez-Santos, Paulina Montero, Patricio A. Díaz, Claudia Aracena, Elías Pinilla, Facundo Barrera, Manuel Castillo, Aida Alvera-Azcárate, Mónica Alvarado, Gabriel Soto, Cécile Pujol, Camila Schwerter, Sara Arenas-Uribe, Pilar Navarro, Guido Mancilla-Gutiérrez, Robinson Altamirano, Javiera San Martín, and Camila Soto-Riquelme
Biogeosciences, 21, 1433–1459, https://doi.org/10.5194/bg-21-1433-2024, https://doi.org/10.5194/bg-21-1433-2024, 2024
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The Patagonian fjords comprise a world region where low-oxygen water and hypoxia conditions are observed. An in situ dataset was used to quantify the mechanism involved in the presence of these conditions in northern Patagonian fjords. Water mass analysis confirmed the contribution of Equatorial Subsurface Water in the advection of the low-oxygen water, and hypoxic conditions occurred when the community respiration rate exceeded the gross primary production.
Ting Wang, Buyun Du, Inke Forbrich, Jun Zhou, Joshua Polen, Elsie M. Sunderland, Prentiss H. Balcom, Celia Chen, and Daniel Obrist
Biogeosciences, 21, 1461–1476, https://doi.org/10.5194/bg-21-1461-2024, https://doi.org/10.5194/bg-21-1461-2024, 2024
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The strong seasonal increases of Hg in aboveground biomass during the growing season and the lack of changes observed after senescence in this salt marsh ecosystem suggest physiologically controlled Hg uptake pathways. The Hg sources found in marsh aboveground tissues originate from a mix of sources, unlike terrestrial ecosystems, where atmospheric GEM is the main source. Belowground plant tissues mostly take up Hg from soils. Overall, the salt marsh currently serves as a small net Hg sink.
Michael R. Roman, Andrew H. Altieri, Denise Breitburg, Erica Ferrer, Natalya D. Gallo, Shin-ichi Ito, Karin Limburg, Kenneth Rose, Moriaki Yasuhara, and Lisa A. Levin
EGUsphere, https://doi.org/10.5194/egusphere-2024-616, https://doi.org/10.5194/egusphere-2024-616, 2024
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Oxygen-depleted ocean waters have increased worldwide. In order to improve our understanding of the impacts of this oxygen loss on marine life it is essential that we develop reliable indicators that track the negative impacts of low oxygen. We review various indicators of oxygen stress for marine animals including their use, research needs and application to confront the challenges of ocean oxygen loss.
Eleanor Simpson, Debby Ianson, Karen E. Kohfeld, Ana C. Franco, Paul A. Covert, Marty Davelaar, and Yves Perreault
Biogeosciences, 21, 1323–1353, https://doi.org/10.5194/bg-21-1323-2024, https://doi.org/10.5194/bg-21-1323-2024, 2024
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Shellfish aquaculture operates in nearshore areas where data on ocean acidification parameters are limited. We show daily and seasonal variability in pH and saturation states of calcium carbonate at nearshore aquaculture sites in British Columbia, Canada, and determine the contributing drivers of this variability. We find that nearshore locations have greater variability than open waters and that the uptake of carbon by phytoplankton is the major driver of pH and saturation state variability.
S. Alejandra Castillo Cieza, Rachel H. R. Stanley, Pierre Marrec, Diana N. Fontaine, E. Taylor Crockford, Dennis J. McGillicuddy Jr., Arshia Mehta, Susanne Menden-Deuer, Emily E. Peacock, Tatiana A. Rynearson, Zoe O. Sandwith, Weifeng Zhang, and Heidi M. Sosik
Biogeosciences, 21, 1235–1257, https://doi.org/10.5194/bg-21-1235-2024, https://doi.org/10.5194/bg-21-1235-2024, 2024
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The coastal ocean in the northeastern USA provides many services, including fisheries and habitats for threatened species. In summer 2019, a bloom occurred of a large unusual phytoplankton, the diatom Hemiaulus, with nitrogen-fixing symbionts. This led to vast changes in productivity and grazing rates in the ecosystem. This work shows that the emergence of one species can have profound effects on ecosystem function. Such changes may become more prevalent as the ocean warms due to climate change.
Claudine Hauri, Brita Irving, Sam Dupont, Rémi Pagés, Donna D. W. Hauser, and Seth L. Danielson
Biogeosciences, 21, 1135–1159, https://doi.org/10.5194/bg-21-1135-2024, https://doi.org/10.5194/bg-21-1135-2024, 2024
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Arctic marine ecosystems are highly susceptible to impacts of climate change and ocean acidification. We present pH and pCO2 time series (2016–2020) from the Chukchi Ecosystem Observatory and analyze the drivers of the current conditions to get a better understanding of how climate change and ocean acidification could affect the ecological niches of organisms.
William Hiles, Lucy C. Miller, Craig Smeaton, and William E. N. Austin
Biogeosciences, 21, 929–948, https://doi.org/10.5194/bg-21-929-2024, https://doi.org/10.5194/bg-21-929-2024, 2024
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Saltmarsh soils may help to limit the rate of climate change by storing carbon. To understand their impacts, they must be accurately mapped. We use drone data to estimate the size of three saltmarshes in NE Scotland. We find that drone imagery, combined with tidal data, can reliably inform our understanding of saltmarsh size. When compared with previous work using vegetation communities, we find that our most reliable new estimates of stored carbon are 15–20 % smaller than previously estimated.
De'Marcus Robinson, Anh L. D. Pham, David J. Yousavich, Felix Janssen, Frank Wenzhöfer, Eleanor C. Arrington, Kelsey M. Gosselin, Marco Sandoval-Belmar, Matthew Mar, David L. Valentine, Daniele Bianchi, and Tina Treude
Biogeosciences, 21, 773–788, https://doi.org/10.5194/bg-21-773-2024, https://doi.org/10.5194/bg-21-773-2024, 2024
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The present study suggests that high release of ferrous iron from the seafloor of the oxygen-deficient Santa Barabara Basin (California) supports surface primary productivity, creating positive feedback on seafloor iron release by enhancing low-oxygen conditions in the basin.
David J. Yousavich, De'Marcus Robinson, Xuefeng Peng, Sebastian J. E. Krause, Frank Wenzhöfer, Felix Janssen, Na Liu, Jonathan Tarn, Franklin Kinnaman, David L. Valentine, and Tina Treude
Biogeosciences, 21, 789–809, https://doi.org/10.5194/bg-21-789-2024, https://doi.org/10.5194/bg-21-789-2024, 2024
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Declining oxygen (O2) concentrations in coastal oceans can threaten people’s ways of life and food supplies. Here, we investigate how mats of bacteria that proliferate on the seafloor of the Santa Barbara Basin sustain and potentially worsen these O2 depletion events through their unique chemoautotrophic metabolism. Our study shows how changes in seafloor microbiology and geochemistry brought on by declining O2 concentrations can help these mats grow as well as how that growth affects the basin.
Krysten Rutherford, Katja Fennel, Lina Garcia Suarez, and Jasmin G. John
Biogeosciences, 21, 301–314, https://doi.org/10.5194/bg-21-301-2024, https://doi.org/10.5194/bg-21-301-2024, 2024
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We downscaled two mid-century (~2075) ocean model projections to a high-resolution regional ocean model of the northwest North Atlantic (NA) shelf. In one projection, the NA shelf break current practically disappears; in the other it remains almost unchanged. This leads to a wide range of possible future shelf properties. More accurate projections of coastal circulation features would narrow the range of possible outcomes of biogeochemical projections for shelf regions.
Lennart Thomas Bach
Biogeosciences, 21, 261–277, https://doi.org/10.5194/bg-21-261-2024, https://doi.org/10.5194/bg-21-261-2024, 2024
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Ocean alkalinity enhancement (OAE) is a widely considered marine carbon dioxide removal method. OAE aims to accelerate chemical rock weathering, which is a natural process that slowly sequesters atmospheric carbon dioxide. This study shows that the addition of anthropogenic alkalinity via OAE can reduce the natural release of alkalinity and, therefore, reduce the efficiency of OAE for climate mitigation. However, the additionality problem could be mitigated via a variety of activities.
Tsuneo Ono, Daisuke Muraoka, Masahiro Hayashi, Makiko Yorifuji, Akihiro Dazai, Shigeyuki Omoto, Takehiro Tanaka, Tomohiro Okamura, Goh Onitsuka, Kenji Sudo, Masahiko Fujii, Ryuji Hamanoue, and Masahide Wakita
Biogeosciences, 21, 177–199, https://doi.org/10.5194/bg-21-177-2024, https://doi.org/10.5194/bg-21-177-2024, 2024
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We carried out parallel year-round observations of pH and related parameters in five stations around the Japan coast. It was found that short-term acidified situations with Omega_ar less than 1.5 occurred at four of five stations. Most of such short-term acidified events were related to the short-term low salinity event, and the extent of short-term pH drawdown at high freshwater input was positively correlated with the nutrient concentration of the main rivers that flow into the coastal area.
K. Mareike Paul, Martijn Hermans, Sami A. Jokinen, Inda Brinkmann, Helena L. Filipsson, and Tom Jilbert
Biogeosciences, 20, 5003–5028, https://doi.org/10.5194/bg-20-5003-2023, https://doi.org/10.5194/bg-20-5003-2023, 2023
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Seawater naturally contains trace metals such as Mo and U, which accumulate under low oxygen conditions on the seafloor. Previous studies have used sediment Mo and U contents as an archive of changing oxygen concentrations in coastal waters. Here we show that in fjords the use of Mo and U for this purpose may be impaired by additional processes. Our findings have implications for the reliable use of Mo and U to reconstruct oxygen changes in fjords.
Hannah Sharpe, Michel Gosselin, Catherine Lalande, Alexandre Normandeau, Jean-Carlos Montero-Serrano, Khouloud Baccara, Daniel Bourgault, Owen Sherwood, and Audrey Limoges
Biogeosciences, 20, 4981–5001, https://doi.org/10.5194/bg-20-4981-2023, https://doi.org/10.5194/bg-20-4981-2023, 2023
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We studied the impact of submarine canyon processes within the Pointe-des-Monts system on biogenic matter export and phytoplankton assemblages. Using data from three oceanographic moorings, we show that the canyon experienced two low-amplitude sediment remobilization events in 2020–2021 that led to enhanced particle fluxes in the deep-water column layer > 2.6 km offshore. Sinking phytoplankton fluxes were lower near the canyon compared to background values from the lower St. Lawrence Estuary.
Dewi Langlet, Florian Mermillod-Blondin, Noémie Deldicq, Arthur Bauville, Gwendoline Duong, Lara Konecny, Mylène Hugoni, Lionel Denis, and Vincent M. P. Bouchet
Biogeosciences, 20, 4875–4891, https://doi.org/10.5194/bg-20-4875-2023, https://doi.org/10.5194/bg-20-4875-2023, 2023
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Benthic foraminifera are single-cell marine organisms which can move in the sediment column. They were previously reported to horizontally and vertically transport sediment particles, yet the impact of their motion on the dissolved fluxes remains unknown. Using microprofiling, we show here that foraminiferal burrow formation increases the oxygen penetration depth in the sediment, leading to a change in the structure of the prokaryotic community.
Masahiko Fujii, Ryuji Hamanoue, Lawrence Patrick Cases Bernardo, Tsuneo Ono, Akihiro Dazai, Shigeyuki Oomoto, Masahide Wakita, and Takehiro Tanaka
Biogeosciences, 20, 4527–4549, https://doi.org/10.5194/bg-20-4527-2023, https://doi.org/10.5194/bg-20-4527-2023, 2023
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This is the first study of the current and future impacts of climate change on Pacific oyster farming in Japan. Future coastal warming and acidification may affect oyster larvae as a result of longer exposure to lower-pH waters. A prolonged spawning period may harm oyster processing by shortening the shipping period and reducing oyster quality. To minimize impacts on Pacific oyster farming, in addition to mitigation measures, local adaptation measures may be required.
Taketoshi Kodama, Atsushi Nishimoto, Ken-ichi Nakamura, Misato Nakae, Naoki Iguchi, Yosuke Igeta, and Yoichi Kogure
Biogeosciences, 20, 3667–3682, https://doi.org/10.5194/bg-20-3667-2023, https://doi.org/10.5194/bg-20-3667-2023, 2023
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Carbon and nitrogen are essential elements for organisms; their stable isotope ratios (13C : 12C, 15N : 14N) are useful tools for understanding turnover and movement in the ocean. In the Sea of Japan, the environment is rapidly being altered by human activities. The 13C : 12C of small organic particles is increased by active carbon fixation, and phytoplankton growth increases the values. The 15N : 14N variations suggest that nitrates from many sources contribute to organic production.
Aubin Thibault de Chanvalon, George W. Luther, Emily R. Estes, Jennifer Necker, Bradley M. Tebo, Jianzhong Su, and Wei-Jun Cai
Biogeosciences, 20, 3053–3071, https://doi.org/10.5194/bg-20-3053-2023, https://doi.org/10.5194/bg-20-3053-2023, 2023
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The intensity of the oceanic trap of CO2 released by anthropogenic activities depends on the alkalinity brought by continental weathering. Between ocean and continent, coastal water and estuaries can limit or favour the alkalinity transfer. This study investigate new interactions between dissolved metals and alkalinity in the oxygen-depleted zone of estuaries.
Joonas J. Virtasalo, Peter Österholm, and Eero Asmala
Biogeosciences, 20, 2883–2901, https://doi.org/10.5194/bg-20-2883-2023, https://doi.org/10.5194/bg-20-2883-2023, 2023
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We mixed acidic metal-rich river water from acid sulfate soils and seawater in the laboratory to study the flocculation of dissolved metals and organic matter in estuaries. Al and Fe flocculated already at a salinity of 0–2 to large organic flocs (>80 µm size). Precipitation of Al and Fe hydroxide flocculi (median size 11 µm) began when pH exceeded ca. 5.5. Mn transferred weakly to Mn hydroxides and Co to the flocs. Up to 50 % of Cu was associated with the flocs, irrespective of seawater mixing.
Moritz Baumann, Allanah Joy Paul, Jan Taucher, Lennart Thomas Bach, Silvan Goldenberg, Paul Stange, Fabrizio Minutolo, and Ulf Riebesell
Biogeosciences, 20, 2595–2612, https://doi.org/10.5194/bg-20-2595-2023, https://doi.org/10.5194/bg-20-2595-2023, 2023
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The sinking velocity of marine particles affects how much atmospheric CO2 is stored inside our oceans. We measured particle sinking velocities in the Peruvian upwelling system and assessed their physical and biochemical drivers. We found that sinking velocity was mainly influenced by particle size and porosity, while ballasting minerals played only a minor role. Our findings help us to better understand the particle sinking dynamics in this highly productive marine system.
Kyle E. Hinson, Marjorie A. M. Friedrichs, Raymond G. Najjar, Maria Herrmann, Zihao Bian, Gopal Bhatt, Pierre St-Laurent, Hanqin Tian, and Gary Shenk
Biogeosciences, 20, 1937–1961, https://doi.org/10.5194/bg-20-1937-2023, https://doi.org/10.5194/bg-20-1937-2023, 2023
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Climate impacts are essential for environmental managers to consider when implementing nutrient reduction plans designed to reduce hypoxia. This work highlights relative sources of uncertainty in modeling regional climate impacts on the Chesapeake Bay watershed and consequent declines in bay oxygen levels. The results demonstrate that planned water quality improvement goals are capable of reducing hypoxia levels by half, offsetting climate-driven impacts on terrestrial runoff.
Linquan Mu, Jaime B. Palter, and Hongjie Wang
Biogeosciences, 20, 1963–1977, https://doi.org/10.5194/bg-20-1963-2023, https://doi.org/10.5194/bg-20-1963-2023, 2023
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Enhancing ocean alkalinity accelerates carbon dioxide removal from the atmosphere. We hypothetically added alkalinity to the Amazon River and examined the increment of the carbon uptake by the Amazon plume. We also investigated the minimum alkalinity addition in which this perturbation at the river mouth could be detected above the natural variability.
Karl M. Attard, Anna Lyssenko, and Iván F. Rodil
Biogeosciences, 20, 1713–1724, https://doi.org/10.5194/bg-20-1713-2023, https://doi.org/10.5194/bg-20-1713-2023, 2023
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Aquatic plants produce a large amount of organic matter through photosynthesis that, following erosion, is deposited on the seafloor. In this study, we show that plant detritus can trigger low-oxygen conditions (hypoxia) in shallow coastal waters, making conditions challenging for most marine animals. We propose that the occurrence of hypoxia may be underestimated because measurements typically do not consider the region closest to the seafloor, where detritus accumulates.
M. James McLaughlin, Cindy Bessey, Gary A. Kendrick, John Keesing, and Ylva S. Olsen
Biogeosciences, 20, 1011–1026, https://doi.org/10.5194/bg-20-1011-2023, https://doi.org/10.5194/bg-20-1011-2023, 2023
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Coral reefs face increasing pressures from environmental change at present. The coral reef framework is produced by corals and calcifying algae. The Kimberley region of Western Australia has escaped land-based anthropogenic impacts. Specimens of the dominant coral and algae were collected from Browse Island's reef platform and incubated in mesocosms to measure calcification and production patterns of oxygen. This study provides important data on reef building and climate-driven effects.
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.
Mathilde Jutras, Alfonso Mucci, Gwenaëlle Chaillou, William A. Nesbitt, and Douglas W. R. Wallace
Biogeosciences, 20, 839–849, https://doi.org/10.5194/bg-20-839-2023, https://doi.org/10.5194/bg-20-839-2023, 2023
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The deep waters of the lower St Lawrence Estuary and gulf have, in the last decades, experienced a strong decline in their oxygen concentration. Below 65 µmol L-1, the waters are said to be hypoxic, with dire consequences for marine life. We show that the extent of the hypoxic zone shows a seven-fold increase in the last 20 years, reaching 9400 km2 in 2021. After a stable period at ~ 65 µmol L⁻¹ from 1984 to 2019, the oxygen level also suddenly decreased to ~ 35 µmol L-1 in 2020.
Sachi Umezawa, Manami Tozawa, Yuichi Nosaka, Daiki Nomura, Hiroji Onishi, Hiroto Abe, Tetsuya Takatsu, and Atsushi Ooki
Biogeosciences, 20, 421–438, https://doi.org/10.5194/bg-20-421-2023, https://doi.org/10.5194/bg-20-421-2023, 2023
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We conducted repetitive observations in Funka Bay, Japan, during the spring bloom 2019. We found nutrient concentration decreases in the dark subsurface layer during the bloom. Incubation experiments confirmed that diatoms could consume nutrients at a substantial rate, even in darkness. We concluded that the nutrient reduction was mainly caused by nutrient consumption by diatoms in the dark.
Dirk Jong, Lisa Bröder, Tommaso Tesi, Kirsi H. Keskitalo, Nikita Zimov, Anna Davydova, Philip Pika, Negar Haghipour, Timothy I. Eglinton, and Jorien E. Vonk
Biogeosciences, 20, 271–294, https://doi.org/10.5194/bg-20-271-2023, https://doi.org/10.5194/bg-20-271-2023, 2023
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With this study, we want to highlight the importance of studying both land and ocean together, and water and sediment together, as these systems function as a continuum, and determine how organic carbon derived from permafrost is broken down and its effect on global warming. Although on the one hand it appears that organic carbon is removed from sediments along the pathway of transport from river to ocean, it also appears to remain relatively ‘fresh’, despite this removal and its very old age.
Cited articles
Al-Hamdani, Z. and Reker, J.: Towards marine landscapes in the Baltic Sea,
BALANCE Interim Report No. 10, available at: http://balance-eu.org/
(last access: 28 April 2017), 2007.
Andersson, A. J., Mackenzie, F. T., and Lerman, A.: Coastal ocean CO2
– carbonic acid-carbonate sediment system of the Anthropocene, Global
Biogeochem. Cy., 20, GB1S92, https://doi.org/10.1029/2005GB002506, 2006.
Bauer, J. E., Cai, W.-J., Raymond, P. A., Bianchi, T. S., Hopkinson, C. S.,
and Regnier, P. A. G.: The changing carbon cycle of the coastal ocean,
Nature, 504, 61–70, https://doi.org/10.1038/nature12857, 2013.
Beldowski, J., Löffler, A., Schneider, B., and Joensuu, L.: Distribution
and biogeochemical control of total CO2 and total alkalinity in the
Baltic Sea, J. Marine Syst., 81, 252–259, https://doi.org/10.1016/j.jmarsys.2009.12.020,
2010.
Berner, R. A.: Sedimentary pyrite formation: An update, Geochim. Cosmochim.
Ac., 48, 605–615, https://doi.org/10.1016/0016-7037(84)90089-9, 1984.
Boesen, C. and Postma, D.: Pyrite formation in anoxic environments of the
Baltic, Am. J. Sci., 288, 575–603, https://doi.org/10.2475/ajs.288.6.575, 1988.
Boudreau, B. P.: Diagenetic Models and Their Implementation, Springer Berlin
Heidelberg, Berlin, Heidelberg, 1997.
Breitburg, D., Levin, L. A., Oschlies, A., Grégoire, M., Chavez, F. P.,
Conley, D. J., Garçon, V., Gilbert, D., Gutiérrez, D., Isensee, K.,
Jacinto, G. S., Limburg, K. E., Montes, I., Naqvi, S. W. A., Pitcher, G. C.,
Rabalais, N. N., Roman, M. R., Rose, K. A., Seibel, B. A., Telszewski, M.,
Yasuhara, M., and Zhang, J.: Declining oxygen in the global ocean and coastal
waters, Science, 359, eaam7240, https://doi.org/10.1126/science.aam7240, 2018.
Brenner, H., Braeckman, U., Le Guitton, M., and Meysman, F. J. R.: The impact
of sedimentary alkalinity release on the water column CO2 system in
the North Sea, Biogeosciences, 13, 841–863,
https://doi.org/10.5194/bg-13-841-2016, 2016.
Buch, K.: Kolsyrejämvikten i Baltiska Havet, Fennia, 68, 29–81, 1945.
Cai, W.-J., Hu, X., Huang, W.-J., Murrell, M. C., Lehrter, J. C., Lohrenz, S.
E., Chou, W.-C., Zhai, W., Hollibaugh, J. T., Wang, Y., Zhao, P., Guo, X.,
Gundersen, K., Dai, M., and Gong, G.-C.: Acidification of subsurface coastal
waters enhanced by eutrophication, Nat. Geosci., 4, 766–770,
https://doi.org/10.1038/ngeo1297, 2011.
Cai, W.-J., Huang, W.-J., Luther, G. W., Pierrot, D., Li, M., Testa, J., Xue,
M., Joesoef, A., Mann, R., Brodeur, J., Xu, Y.-Y., Chen, B., Hussain, N.,
Waldbusser, G. G., Cornwell, J., and Kemp, W. M.: Redox reactions and weak
buffering capacity lead to acidification in the Chesapeake Bay, Nat. Commun.,
8, 369, https://doi.org/10.1038/s41467-017-00417-7, 2017.
Carstensen, J., Andersen, J. H., Gustafsson, B. G., and Conley, D. J.:
Deoxygenation of the Baltic Sea during the last century, P. Natl. Acad. Sci.
USA, 111, 5628–5633, https://doi.org/10.1073/pnas.1323156111, 2014.
Chen, C.-T. A.: Shelf-vs. dissolution-generated alkalinity above the chemical
lysocline, Deep-Sea Res. Pt. II, 49, 5365–5375,
https://doi.org/10.1016/S0967-0645(02)00196-0, 2002.
Chen, C.-T. A. and Wang, S.-L.: Carbon, alkalinity and nutrient budgets on
the East China Sea continental shelf, J. Geophys. Res.-Oceans, 104,
20675–20686, https://doi.org/10.1029/1999JC900055, 1999.
Claremar, B., Wällstedt, T., Rutgersson, A., and Omstedt, A.: Deposition
of acidifying and neutralising compounds over the Baltic Sea drainage basin
between 1960 and 2006, Boreal Environ. Res., 18, 425–445, 2013.
Diaz, R. J. and Rosenberg, R.: Spreading Dead Zones and Consequences for
Marine Ecosystems, Science, 321, 926–929, https://doi.org/10.1126/science.1156401, 2008.
Dickson, A. G.: An exact definition of total alkalinity and a procedure for
the estimation of alkalinity and total inorganic carbon from titration data,
Deep-Sea Res. Pt. A, 28, 609–623, https://doi.org/10.1016/0198-0149(81)90121-7, 1981.
Dijkstra, N., Hagens, M., Egger, M., and Slomp, C. P.: Post-depositional
formation of vivianite-type minerals alters sediment phosphorus records,
Biogeosciences, 15, 861–883, https://doi.org/10.5194/bg-15-861-2018, 2018.
Dyrssen, D.: The Baltic-Kattegat-Skagerrak Estuarine System, Estuaries, 16,
446, https://doi.org/10.2307/1352592, 1993.
Egger, M., Jilbert, T., Behrends, T., Rivard, C., and Slomp, C. P.: Vivianite
is a major sink for phosphorus in methanogenic coastal surface sediments,
Geochim. Cosmochim. Ac., 169, 217–235, https://doi.org/10.1016/j.gca.2015.09.012, 2015a.
Egger, M., Rasigraf, O., Sapart, C. J., Jilbert, T., Jetten, M. S. M.,
Röckmann, T., van der Veen, C., Bândă, N., Kartal, B., Ettwig, K.
F., and Slomp, C. P.: Iron-Mediated Anaerobic Oxidation of Methane in
Brackish Coastal Sediments, Environ. Sci. Technol., 49, 277–283,
https://doi.org/10.1021/es503663z, 2015b.
Egger, M., Kraal, P., Jilbert, T., Sulu-Gambari, F., Sapart, C. J.,
Röckmann, T., and Slomp, C. P.: Anaerobic oxidation of methane alters
sediment records of sulfur, iron and phosphorus in the Black Sea,
Biogeosciences, 13, 5333–5355, https://doi.org/10.5194/bg-13-5333-2016,
2016.
Egger, M., Hagens, M., Sapart, C. J., Dijkstra, N., van Helmond, N. A. G. M.,
Mogollón, J. M., Risgaard-Petersen, N., van der Veen, C., Kasten, S.,
Riedinger, N., Böttcher, M. E., Röckmann, T., Jørgensen, B. B.,
and Slomp, C. P.: Iron oxide reduction in methane-rich deep Baltic Sea
sediments, Geochim. Cosmochim. Ac., 207, 256–276,
https://doi.org/10.1016/j.gca.2017.03.019, 2017.
Gattuso, J. P., Frankignoulle, M., and Wollast, R.: Carbon and carbonate
metabolism in coastal and aquatic ecosystems, Annu. Rev. Ecol. Syst., 29,
405–434, 1998.
Gripenberg, S.: On the alkalinity of Baltic waters, Journal du Conseil
International pour l'Exploration de la Mer, 26, 5–20, 1960.
Gustafsson, B. G.: Time-dependent modeling of the Baltic entrance area. 1.
Quantification of circulation and residence times in the Kattegat and the
Straits of the Baltic sill, Estuaries, 23, 231–252, https://doi.org/10.2307/1352830,
2000.
Gustafsson, B. G.: A Time-dependent Coupled-basin Model of the Baltic Sea,
C47, Earth Sciences Centre, Göteborg University, Göteborg, 2003.
Gustafsson, B. G., Schenk, F., Blenckner, T., Eilola, K., Meier, H. E. M.,
Müller-Karulis, B., Neumann, T., Ruoho-Airola, T., Savchuk, O. P., and
Zorita, E.: Reconstructing the Development of Baltic Sea Eutrophication
1850–2006, AMBIO, 41, 534–548, https://doi.org/10.1007/s13280-012-0318-x, 2012.
Gustafsson, E., Deutsch, B., Gustafsson, B. G., Humborg, C., and Mörth,
C.-M.: Carbon cycling in the Baltic Sea – The fate of allochthonous organic
carbon and its impact on air–sea CO2 exchange, J. Marine Syst., 129,
289–302, https://doi.org/10.1016/j.jmarsys.2013.07.005, 2014a.
Gustafsson, E., Wällstedt, T., Humborg, C., Mörth, C.-M., and
Gustafsson, B. G.: External total alkalinity loads versus internal
generation: The influence of nonriverine alkalinity sources in the Baltic
Sea, Global Biogeochem. Cy., 28, 1358–1370, https://doi.org/10.1002/2014GB004888, 2014b.
Gustafsson, E., Omstedt, A., and Gustafsson, B. G.: The air-water CO2
exchange of a coastal sea – A sensitivity study on factors that influence
the absorption and outgassing of CO2 in the Baltic Sea, J. Geophys.
Res.-Oceans, 120, 5342–5357, https://doi.org/10.1002/2015JC010832, 2015.
Gustafsson, E., Savchuk, O. P., Gustafsson, B. G., and Müller-Karulis,
B.: Key processes in the coupled carbon, nitrogen, and phosphorus cycling of
the Baltic Sea, Biogeochemistry, 134, 301–317,
https://doi.org/10.1007/s10533-017-0361-6, 2017.
Hagens, M., Hunter, K. A., Liss, P. S., and Middelburg, J. J.: Biogeochemical
context impacts seawater pH changes resulting from atmospheric sulfur and
nitrogen deposition, Geophys. Res. Lett., 41, 935–941,
https://doi.org/10.1002/2013GL058796, 2014.
Hagens, M., Slomp, C. P., Meysman, F. J. R., Seitaj, D., Harlay, J., Borges,
A. V., and Middelburg, J. J.: Biogeochemical processes and buffering capacity
concurrently affect acidification in a seasonally hypoxic coastal marine
basin, Biogeosciences, 12, 1561–1583,
https://doi.org/10.5194/bg-12-1561-2015, 2015.
Hassellöv, I.-M., Turner, D. R., Lauer, A., and Corbett, J. J.: Shipping
contributes to ocean acidification, Geophys. Res. Lett., 40, 2731–2736,
https://doi.org/10.1002/grl.50521, 2013.
Hofmann, A. F., Meysman, F. J. R., Soetaert, K., and Middelburg, J. J.: A
step-by-step procedure for pH model construction in aquatic systems,
Biogeosciences, 5, 227–251, https://doi.org/10.5194/bg-5-227-2008, 2008.
Hu, X. and Cai, W.-J.: An assessment of ocean margin anaerobic processes on
oceanic alkalinity budget, Global Biogeochem. Cy., 25, GB3003,
https://doi.org/10.1029/2010GB003859, 2011a.
Hu, X. and Cai, W.-J.: The impact of denitrification on the atmospheric
CO2 uptake potential of seawater, Mar. Chem., 127, 192–198,
https://doi.org/10.1016/j.marchem.2011.09.008, 2011b.
Jilbert, T. and Slomp, C. P.: Iron and manganese shuttles control the
formation of authigenic phosphorus minerals in the euxinic basins of the
Baltic Sea, Geochim. Cosmochim. Ac., 107, 155–169,
https://doi.org/10.1016/j.gca.2013.01.005, 2013.
Jilbert, T., Slomp, C. P., Gustafsson, B. G., and Boer, W.: (Table B1)
Geochemistry of Baltic Sea sediments, PANGAEA, https://doi.org/10.1594/PANGAEA.775277,
2011.
Jilbert, T., Slomp, C. P., Gustafsson, B. G., and Boer, W.: (Table A1)
Geochemistry of Baltic Sea porewater samples and bottom water oxygen
concentrations, PANGAEA, https://doi.org/10.1594/PANGAEA.775278, 2012.
Jørgensen, B. B.: The Sulfur Cycle of a Coastal Marine Sediment
(Limfjorden, Denmark), Limnol. Oceanogr., 22, 814–832, 1977.
Krumins, V., Gehlen, M., Arndt, S., Van Cappellen, P., and Regnier, P.:
Dissolved inorganic carbon and alkalinity fluxes from coastal marine
sediments: model estimates for different shelf environments and sensitivity
to global change, Biogeosciences, 10, 371–398,
https://doi.org/10.5194/bg-10-371-2013, 2013.
Kuliński, K., Schneider, B., Hammer, K., Machulik, U., and Schulz-Bull,
D.: The influence of dissolved organic matter on the acid–base system of the
Baltic Sea, J. Marine Syst., 132, 106–115,
https://doi.org/10.1016/j.jmarsys.2014.01.011, 2014.
Laurent, A., Fennel, K., Ko, D. S., and Lehrter, J.: Climate Change Projected
to Exacerbate Impacts of Coastal Eutrophication in the Northern Gulf of
Mexico, J. Geophys. Res.-Oceans, 123, 3408–3426, https://doi.org/10.1002/2017JC013583,
2018.
Lenz, C., Jilbert, T., Conley, D. J., and Slomp, C. P.: Hypoxia-driven
variations in iron and manganese shuttling in the Baltic Sea over the past
8 kyr, Geochem. Geophy. Geosy., 16, 3754–3766, https://doi.org/10.1002/2015GC005960,
2015a.
Lenz, C., Jilbert, T., Conley, D. J., Wolthers, M., and Slomp, C. P.: Are
recent changes in sediment manganese sequestration in the euxinic basins of
the Baltic Sea linked to the expansion of hypoxia?, Biogeosciences, 12,
4875–4894, https://doi.org/10.5194/bg-12-4875-2015, 2015b.
Lenz, C., Jilbert, T., Conley, D. J., and Slomp, C. P.: Total organic carbon
and selecetd elements of sediment core F80-A, PANGAEA,
https://doi.org/10.1594/PANGAEA.854127, 2015c.
Lepland, A. and Stevens, R. L.: Manganese authigenesis in the Landsort Deep,
Baltic Sea, Mar. Geol., 151, 1–25, https://doi.org/10.1016/S0025-3227(98)00046-2, 1998.
Łukawska-Matuszewska, K.: Contribution of non-carbonate inorganic and
organic alkalinity to total measured alkalinity in pore waters in marine
sediments (Gulf of Gdansk, S-E Baltic Sea), Mar. Chem., 186, 211–220,
https://doi.org/10.1016/j.marchem.2016.10.002, 2016.
Łukawska-Matuszewska, K. and Graca, B.: Pore water alkalinity below the
permanent halocline in the Gdańsk Deep (Baltic Sea) – Concentration
variability and benthic fluxes, Mar. Chem., 204, 49–61,
https://doi.org/10.1016/j.marchem.2018.05.011, 2018.
Łukawska-Matuszewska, K., Grzybowski, W., Szewczun, A., and Tarasiewicz,
P.: Constituents of organic alkalinity in pore water of marine sediments,
Mar. Chem., 200, 22–32, https://doi.org/10.1016/j.marchem.2018.01.012, 2018.
Middelburg, J. J. and Levin, L. A.: Coastal hypoxia and sediment
biogeochemistry, Biogeosciences, 6, 1273–1293,
https://doi.org/10.5194/bg-6-1273-2009, 2009.
Millero, F. J., Sotolongo, S., and Izaguirre, M.: The oxidation kinetics of
Fe(II) in seawater, Geochim. Cosmochim. Ac., 51, 793–801,
https://doi.org/10.1016/0016-7037(87)90093-7, 1987.
Müller, J. D., Schneider, B., and Rehder, G.: Long-term alkalinity trends
in the Baltic Sea and their implications for CO2-induced
acidification, Limnol. Oceanogr., 61, 1984–2002, https://doi.org/10.1002/lno.10349,
2016.
Ohlson, M. and Anderson, L.: Recent investigation of total carbonate in the
Baltic Sea: changes from the past as a result of acid rain?, Mar. Chem., 30,
259–267, https://doi.org/10.1016/0304-4203(90)90075-N, 1990.
Omstedt, A., Edman, M., Claremar, Bj., Frodin, P., Gustafsson, E., Humborg,
C., Hägg, H., Mörth, M., Rutgersson, A., Schurgers, G., Smith, B.,
Wällstedt, T., and Yurova, A.: Future changes in the Baltic Sea
acid–base (pH) and oxygen balances, Tellus B, 64, 19586,
https://doi.org/10.3402/tellusb.v64i0.19586, 2012.
Omstedt, A., Edman, M., Claremar, B., and Rutgersson, A.: Modelling the
contributions to marine acidification from deposited SOx,
NOx, and NHx in the Baltic Sea: Past and
present situations, Cont. Shelf Res., 111, 234–249,
https://doi.org/10.1016/j.csr.2015.08.024, 2015.
Perttilä, M., Terrihauta, S., Lemponen, P., Riikonen, J., Grau Garcia,
M., Hernández Abós, E., and Rodriquez Moles, J.:
Alkalinity–calcium–salinity relations in the Baltic Sea 1. Data description
and general considerations, Meri: Report Series of the Finnish Institute of
Marine Research, Finnish Institute of Marine Research, 2006.
Rabalais, N. N., Cai, W.-J., Carstensen, J., Conley, D. J., Fry, B., Hu, X.,
Quiñones-Rivera, Z., Rosenberg, R., Slomp, C. P., Turner, R. E., Voss,
M., Wissel, B., and Zhang, J.: Eutrophication-Driven Deoxygenation in the
Coastal Ocean, Oceanography, 27, 172–183, 2014.
Raiswell, R. and Canfield, D. E.: The Iron Biogeochemical Cycle Past and
Present, Geochem. Perspect., 1, 1–2, 2012.
Reed, D. C., Gustafsson, B. G., and Slomp, C. P.: Shelf-to-basin iron
shuttling enhances vivianite formation in deep Baltic Sea sediments, Earth
Planet. Sc. Lett., 434, 241–251, https://doi.org/10.1016/j.epsl.2015.11.033,
2016.
Regnier, P., Friedlingstein, P., Ciais, P., Mackenzie, F. T., Gruber, N.,
Janssens, I. A., Laruelle, G. G., Lauerwald, R., Luyssaert, S., Andersson, A.
J., Arndt, S., Arnosti, C., Borges, A. V., Dale, A. W., Gallego-Sala, A.,
Goddéris, Y., Goossens, N., Hartmann, J., Heinze, C., Ilyina, T., Joos,
F., LaRowe, D. E., Leifeld, J., Meysman, F. J. R., Munhoven, G., Raymond, P.
A., Spahni, R., Suntharalingam, P., and Thullner, M.: Anthropogenic
perturbation of the carbon fluxes from land to ocean, Nat. Geosci., 6,
597–607, https://doi.org/10.1038/ngeo1830, 2013.
Riedinger, N., Formolo, M. J., Lyons, T. W., Henkel, S., Beck, A., and
Kasten, S.: An inorganic geochemical argument for coupled anaerobic oxidation
of methane and iron reduction in marine sediments, Geobiology, 12, 172–181,
https://doi.org/10.1111/gbi.12077, 2014.
Ruppin, E.: Die Alkalinität des Meerwassers, Wissenschaftliche
Meeresuntersuchungen Abt. Kiel, 11, 277–302, 1909.
Sarmiento, J. L. and Gruber, N.: Ocean Biogeochemical Dynamics, Princeton
University Press, Princeton, NJ, 2006.
Savchuk, O. P., Gustafsson, B. G., and Müller-Karulis, B.: BALTSEM – a
marine model for the decision support within the Baltic Sea Region, Technical
Report No. 7, Baltic Nest Institute, Stockholm University, 2012.
Slomp, C. P., Mort, H. P., Jilbert, T., Reed, D. C., Gustafsson, B. G., and
Wolthers, M.: Coupled Dynamics of Iron and Phosphorus in Sediments of an
Oligotrophic Coastal Basin and the Impact of Anaerobic Oxidation of Methane,
PLOS ONE, 8, e62386, https://doi.org/10.1371/journal.pone.0062386, 2013.
Soetaert, K., Hofmann, A. F., Middelburg, J. J., Meysman, F. J. R., and
Greenwood, J.: The effect of biogeochemical processes on pH, Mar. Chem., 105,
30–51, https://doi.org/10.1016/j.marchem.2006.12.012, 2007.
Stigebrandt, A. and Gustafsson, B. G.: Improvement of Baltic Proper Water
Quality Using Large-scale Ecological Engineering, AMBIO, 36, 280–286,
https://doi.org/10.1579/0044-7447(2007)36[280:IOBPWQ]2.0.CO;2, 2007.
Sun, X., Mörth, C.-M., Humborg, C., and Gustafsson, B.: Temporal and
spatial variations of rock weathering and CO2 consumption in the
Baltic Sea catchment, Chem. Geol., 466, 57–69,
https://doi.org/10.1016/j.chemgeo.2017.04.028, 2017.
Szymczycha, B., Maciejewska, A., Winogradow, A., and Pempkowiak, J.: Could
submarine groundwater discharge be a significant carbon source to the
southern Baltic Sea?, Oceanologia, 56, 327–347, https://doi.org/10.5697/oc.56-2.327,
2014.
Thomas, H. and Schneider, B.: The seasonal cycle of carbon dioxide in Baltic
Sea surface waters, J. Marine Syst., 22, 53–67,
https://doi.org/10.1016/S0924-7963(99)00030-5, 1999.
Thomas, H., Schiettecatte, L.-S., Suykens, K., Koné, Y. J. M., Shadwick,
E. H., Prowe, A. E. F., Bozec, Y., de Baar, H. J. W., and Borges, A. V.:
Enhanced ocean carbon storage from anaerobic alkalinity generation in coastal
sediments, Biogeosciences, 6, 267–274,
https://doi.org/10.5194/bg-6-267-2009, 2009.
Tyrrell, T., Schneider, B., Charalampopoulou, A., and Riebesell, U.:
Coccolithophores and calcite saturation state in the Baltic and Black Seas,
Biogeosciences, 5, 485–494, https://doi.org/10.5194/bg-5-485-2008, 2008.
Ulfsbo, A., Hulth, S., and Anderson, L. G.: pH and biogeochemical processes
in the Gotland Basin of the Baltic Sea, Mar. Chem., 127, 20–30,
https://doi.org/10.1016/j.marchem.2011.07.004, 2011.
Ulfsbo, A., Kuliński, K., Anderson, L. G., and Turner, D. R.: Modelling
organic alkalinity in the Baltic Sea using a Humic-Pitzer approach, Mar.
Chem., 168, 18–26, https://doi.org/10.1016/j.marchem.2014.10.013, 2015.
van Heuven, S., Pierrot, D., Rae, J. W. B., Lewis, E., and Wallace, D. W. R.:
MATLAB Program Developed for CO2 System Calculations,
ORNL/CDIAC-105b, Carbon Dioxide Information Analysis Center, Oak Ridge
National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee,
https://doi.org/10.3334/CDIAC/otg.CO2SYS_MATLAB_v1.1, 2011.
Wallmann, K., Aloisi, G., Haeckel, M., Tishchenko, P., Pavlova, G., Greinert,
J., Kutterolf, S., and Eisenhauer, A.: Silicate weathering in anoxic marine
sediments, Geochim. Cosmochim. Ac., 72, 2895–2918,
https://doi.org/10.1016/j.gca.2008.03.026, 2008.
Wang, Y. and Van Cappellen, P.: A multicomponent reactive transport
model of
early diagenesis: Application to redox cycling in coastal marine sediments,
Geochim. Cosmochim. Ac., 60, 2993–3014, https://doi.org/10.1016/0016-7037(96)00140-8,
1996.
Wolf-Gladrow, D. A., Zeebe, R. E., Klaas, C., Körtzinger, A., and
Dickson, A. G.: Total alkalinity: The explicit conservative expression and
its application to biogeochemical processes, Mar. Chem., 106, 287–300,
https://doi.org/10.1016/j.marchem.2007.01.006, 2007.
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Short summary
This work highlights that iron (Fe) dynamics plays a key role in the release of alkalinity from sediments, as exemplified for the Baltic Sea. It furthermore demonstrates that burial of Fe sulfides should be included in alkalinity budgets of low-oxygen basins. The sedimentary alkalinity generation may undergo large changes depending on both organic matter loads and oxygen conditions. Enhanced release of alkalinity from the seafloor can increase the CO2 storage capacity of seawater.
This work highlights that iron (Fe) dynamics plays a key role in the release of alkalinity from...
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