Articles | Volume 21, issue 3
https://doi.org/10.5194/bg-21-789-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-21-789-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
14 Feb 2024
Research article |
| 14 Feb 2024
| 14 Feb 2024
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
Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, 595 Charles E. Young Drive East, Los Angeles, CA 90095, USA
De'Marcus Robinson
Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, Math Science Building, 520 Portola Plaza, Los Angeles, CA 90095, USA
Xuefeng Peng
School of Earth, Ocean, and Environment, University of South Carolina, 701 Sumter Street, Columbia, SC 29208, USA
Sebastian J. E. Krause
Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, 595 Charles E. Young Drive East, Los Angeles, CA 90095, USA
Earth Research Institute, 6832 Ellison Hall, University of California, Santa Barbara, CA 93106-3060, USA
Frank Wenzhöfer
HGF-MPG Joint Research Group for Deep-Sea Ecology and Technology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
HGF-MPG Joint Research Group for Deep-Sea Ecology and Technology, Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany
Department of Biology, HADAL center, University of Southern Denmark, 5230 Odense M, Denmark
Felix Janssen
HGF-MPG Joint Research Group for Deep-Sea Ecology and Technology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
HGF-MPG Joint Research Group for Deep-Sea Ecology and Technology, Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany
Na Liu
Department of Earth Science and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA
Jonathan Tarn
Department of Earth Science and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA
Franklin Kinnaman
Department of Earth Science and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA
David L. Valentine
Department of Earth Science and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA
Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, 595 Charles E. Young Drive East, Los Angeles, CA 90095, USA
Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, Math Science Building, 520 Portola Plaza, Los Angeles, CA 90095, USA
Related authors
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
Short summary
Short summary
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.
Sebastian J. E. Krause, Jiarui Liu, David J. Yousavich, DeMarcus Robinson, David W. Hoyt, Qianhui Qin, Frank Wenzhöfer, Felix Janssen, David L. Valentine, and Tina Treude
Biogeosciences, 20, 4377–4390, https://doi.org/10.5194/bg-20-4377-2023, https://doi.org/10.5194/bg-20-4377-2023, 2023
Short summary
Short summary
Methane is a potent greenhouse gas, and hence it is important to understand its sources and sinks in the environment. Here we present new data from organic-rich surface sediments below an oxygen minimum zone off the coast of California (Santa Barbara Basin) demonstrating the simultaneous microbial production and consumption of methane, which appears to be an important process preventing the build-up of methane in these sediments and the emission into the water column and atmosphere.
Xuefeng Peng, David J. Yousavich, Annie Bourbonnais, Frank Wenzhoefer, Felix Janssen, Tina Treude, and David L. Valentine
EGUsphere, https://doi.org/10.5194/egusphere-2023-1498, https://doi.org/10.5194/egusphere-2023-1498, 2023
Short summary
Short summary
Biologically available (fixed) nitrogen (N) is a limiting nutrient for life in the ocean. Under low oxygen conditions, fixed N is either removed via denitrification or retained via dissimilatory nitrate reduction to ammonia (DNRA). Using in-situ incubations in the Santa Barbara Basin which undergoes seasonal anoxia, we found that benthic denitrification was the dominant nitrate reduction process, while nitrate availability and organic matter content control the relative importance of DNRA.
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
Short summary
Short summary
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.
Weiyi Tang, Bess B. Ward, Michael Beman, Laura Bristow, Darren Clark, Sarah Fawcett, Claudia Frey, François Fripiat, Gerhard J. Herndl, Mhlangabezi Mdutyana, Fabien Paulot, Xuefeng Peng, Alyson E. Santoro, Takuhei Shiozaki, Eva Sintes, Charles Stock, Xin Sun, Xianhui S. Wan, Min N. Xu, and Yao Zhang
Earth Syst. Sci. Data, 15, 5039–5077, https://doi.org/10.5194/essd-15-5039-2023, https://doi.org/10.5194/essd-15-5039-2023, 2023
Short summary
Short summary
Nitrification and nitrifiers play an important role in marine nitrogen and carbon cycles by converting ammonium to nitrite and nitrate. Nitrification could affect microbial community structure, marine productivity, and the production of nitrous oxide – a powerful greenhouse gas. We introduce the newly constructed database of nitrification and nitrifiers in the marine water column and guide future research efforts in field observations and model development of nitrification.
Sebastian J. E. Krause, Jiarui Liu, David J. Yousavich, DeMarcus Robinson, David W. Hoyt, Qianhui Qin, Frank Wenzhöfer, Felix Janssen, David L. Valentine, and Tina Treude
Biogeosciences, 20, 4377–4390, https://doi.org/10.5194/bg-20-4377-2023, https://doi.org/10.5194/bg-20-4377-2023, 2023
Short summary
Short summary
Methane is a potent greenhouse gas, and hence it is important to understand its sources and sinks in the environment. Here we present new data from organic-rich surface sediments below an oxygen minimum zone off the coast of California (Santa Barbara Basin) demonstrating the simultaneous microbial production and consumption of methane, which appears to be an important process preventing the build-up of methane in these sediments and the emission into the water column and atmosphere.
Xuefeng Peng, David J. Yousavich, Annie Bourbonnais, Frank Wenzhoefer, Felix Janssen, Tina Treude, and David L. Valentine
EGUsphere, https://doi.org/10.5194/egusphere-2023-1498, https://doi.org/10.5194/egusphere-2023-1498, 2023
Short summary
Short summary
Biologically available (fixed) nitrogen (N) is a limiting nutrient for life in the ocean. Under low oxygen conditions, fixed N is either removed via denitrification or retained via dissimilatory nitrate reduction to ammonia (DNRA). Using in-situ incubations in the Santa Barbara Basin which undergoes seasonal anoxia, we found that benthic denitrification was the dominant nitrate reduction process, while nitrate availability and organic matter content control the relative importance of DNRA.
Autun Purser, Laura Hehemann, Lilian Boehringer, Ellen Werner, Santiago E. A. Pineda-Metz, Lucie Vignes, Axel Nordhausen, Moritz Holtappels, and Frank Wenzhoefer
Earth Syst. Sci. Data, 14, 3635–3648, https://doi.org/10.5194/essd-14-3635-2022, https://doi.org/10.5194/essd-14-3635-2022, 2022
Short summary
Short summary
Within this paper we present the seafloor images, maps and acoustic camera data collected by a towed underwater research platform deployed in 20 locations across the eastern Weddell Sea, Antarctica, during the PS124 COSMUS expedition with the research icebreaker RV Polarstern in 2021. The 20 deployments highlight the great variability in seafloor structure and faunal communities present. Of key interest was the discovery of the largest fish nesting colony discovered globally to date.
Samuel T. Wilson, Alia N. Al-Haj, Annie Bourbonnais, Claudia Frey, Robinson W. Fulweiler, John D. Kessler, Hannah K. Marchant, Jana Milucka, Nicholas E. Ray, Parvadha Suntharalingam, Brett F. Thornton, Robert C. Upstill-Goddard, Thomas S. Weber, Damian L. Arévalo-Martínez, Hermann W. Bange, Heather M. Benway, Daniele Bianchi, Alberto V. Borges, Bonnie X. Chang, Patrick M. Crill, Daniela A. del Valle, Laura Farías, Samantha B. Joye, Annette Kock, Jabrane Labidi, Cara C. Manning, John W. Pohlman, Gregor Rehder, Katy J. Sparrow, Philippe D. Tortell, Tina Treude, David L. Valentine, Bess B. Ward, Simon Yang, and Leonid N. Yurganov
Biogeosciences, 17, 5809–5828, https://doi.org/10.5194/bg-17-5809-2020, https://doi.org/10.5194/bg-17-5809-2020, 2020
Short summary
Short summary
The oceans are a net source of the major greenhouse gases; however there has been little coordination of oceanic methane and nitrous oxide measurements. The scientific community has recently embarked on a series of capacity-building exercises to improve the interoperability of dissolved methane and nitrous oxide measurements. This paper derives from a workshop which discussed the challenges and opportunities for oceanic methane and nitrous oxide research in the near future.
Massimiliano Molari, Felix Janssen, Tobias R. Vonnahme, Frank Wenzhöfer, and Antje Boetius
Biogeosciences, 17, 3203–3222, https://doi.org/10.5194/bg-17-3203-2020, https://doi.org/10.5194/bg-17-3203-2020, 2020
Short summary
Short summary
Industrial-scale mining of deep-sea polymetallic nodules will remove nodules in large areas of the sea floor. We describe community composition of microbes associated with nodules of the Peru Basin. Our results show that nodules provide a unique ecological niche, playing an important role in shaping the diversity of the benthic deep-sea microbiome and potentially in element fluxes. We believe that our findings are highly relevant to expanding our knowledge of the impact associated with mining.
Laura Haffert, Matthias Haeckel, Henko de Stigter, and Felix Janssen
Biogeosciences, 17, 2767–2789, https://doi.org/10.5194/bg-17-2767-2020, https://doi.org/10.5194/bg-17-2767-2020, 2020
Short summary
Short summary
Deep-sea mining for polymetallic nodules is expected to have severe environmental impacts. Through prognostic modelling, this study aims to provide a holistic assessment of the biogeochemical recovery after a disturbance event. It was found that the recovery strongly depends on the impact type; e.g. complete removal of the surface sediment reduces seafloor nutrient fluxes over centuries.
Nathaniel Kemnitz, William M. Berelson, Douglas E. Hammond, Laura Morine, Maria Figueroa, Timothy W. Lyons, Simon Scharf, Nick Rollins, Elizabeth Petsios, Sydnie Lemieux, and Tina Treude
Biogeosciences, 17, 2381–2396, https://doi.org/10.5194/bg-17-2381-2020, https://doi.org/10.5194/bg-17-2381-2020, 2020
Short summary
Short summary
Our paper shows how sedimentation in a very low oxygen setting provides a unique record of environmental change. We look at the past 250 years through the filter of sediment accumulation via radioisotope dating and other physical and chemical analyses of these sediments. We conclude, remarkably, that there has been very little change in net sediment mass accumulation through the past 100–150 years, yet just prior to 1900 CE, sediments were accumulating at 50 %–70 % of today's rate.
Ulrike Braeckman, Felix Janssen, Gaute Lavik, Marcus Elvert, Hannah Marchant, Caroline Buckner, Christina Bienhold, and Frank Wenzhöfer
Biogeosciences, 15, 6537–6557, https://doi.org/10.5194/bg-15-6537-2018, https://doi.org/10.5194/bg-15-6537-2018, 2018
Short summary
Short summary
Global warming has altered Arctic phytoplankton communities, with unknown effects on deep-sea communities that depend strongly on food produced at the surface. We compared the responses of Arctic deep-sea benthos to input of phytodetritus from diatoms and coccolithophorids. Coccolithophorid carbon was 5× less recycled than diatom carbon. The utilization of the coccolithophorid carbon may be less efficient, so a shift from diatom to coccolithophorid blooms could entail a delay in carbon cycling.
Ralf Hoffmann, Ulrike Braeckman, Christiane Hasemann, and Frank Wenzhöfer
Biogeosciences, 15, 4849–4869, https://doi.org/10.5194/bg-15-4849-2018, https://doi.org/10.5194/bg-15-4849-2018, 2018
Short summary
Short summary
Our study links surface sea-ice cover and benthic oxygen fluxes in the Fram Strait via primary production, food supply, benthic community, and their functions. We show that sea-ice cover and water depth are the most important factors influencing the ecosystem. However, in water depths > 1500 m, the effect of sea ice fades out. Further, we discuss primary production and benthic remineralization patterns and developed a potential scenario for the benthic remineralization in a future Arctic Ocean.
Johanna Maltby, Lea Steinle, Carolin R. Löscher, Hermann W. Bange, Martin A. Fischer, Mark Schmidt, and Tina Treude
Biogeosciences, 15, 137–157, https://doi.org/10.5194/bg-15-137-2018, https://doi.org/10.5194/bg-15-137-2018, 2018
Short summary
Short summary
The activity and environmental controls of methanogenesis (MG) within the sulfate-reducing zone (0–30 cm below the seafloor) were investigated in organic-rich sediments of the seasonally hypoxic Eckernförde Bay, SW Baltic Sea. MG activity was mostly linked to non-competitive substrates. The major controls identified were organic matter availability, C / N, temperature, and O2 in the water column, revealing higher rates in warm, stratified, hypoxic seasons compared to colder, oxygenated seasons.
Lea Steinle, Johanna Maltby, Tina Treude, Annette Kock, Hermann W. Bange, Nadine Engbersen, Jakob Zopfi, Moritz F. Lehmann, and Helge Niemann
Biogeosciences, 14, 1631–1645, https://doi.org/10.5194/bg-14-1631-2017, https://doi.org/10.5194/bg-14-1631-2017, 2017
Short summary
Short summary
Large amounts of methane are produced in anoxic, coastal sediments, from which it can seep into the overlying water column. Aerobic oxidation of methane (MOx) mediated by methanotrophic bacteria is an important sink for methane before its evasion to the atmosphere. In a 2-year seasonal study, we investigated the spatio-temporal variability of MOx in a seasonally hypoxic coastal inlet using radiotracer-based methods. In experiments, we assessed the effect of variable oxygen concentrations on MOx.
Jessica Gier, Stefan Sommer, Carolin R. Löscher, Andrew W. Dale, Ruth A. Schmitz, and Tina Treude
Biogeosciences, 13, 4065–4080, https://doi.org/10.5194/bg-13-4065-2016, https://doi.org/10.5194/bg-13-4065-2016, 2016
Short summary
Short summary
Benthic nitrogen fixation and sulfate reduction were investigated in the Peruvian oxygen minimum zone. The data suggest a coupling of both activities to a large extent, but that also sulfide and organic matter availability are controlling the benthic diazotrophy in this area. The molecular analysis confirms the presence of heterotrophic diazotrophs. This work improves our understanding of N cycling in OMZ sediments and the understanding of N sources in the marine environment.
J. Maltby, S. Sommer, A. W. Dale, and T. Treude
Biogeosciences, 13, 283–299, https://doi.org/10.5194/bg-13-283-2016, https://doi.org/10.5194/bg-13-283-2016, 2016
Short summary
Short summary
The concurrence of methanogenesis and sulfate reduction was investigated in surface sediments (0–25cm b.s.f.) traversing the Peruvian margin. Surface methanogenesis was mainly based on non-competitive substrates to avoid competition with sulfate reducers. Accordingly, surface methanogenesis was mainly controlled by the availability of labile organic matter. The high relevance of surface methanogenesis especially on the shelf indicates its underestimated role within benthic methane budgeting.
P. Steeb, S. Krause, P. Linke, C. Hensen, A. W. Dale, M. Nuzzo, and T. Treude
Biogeosciences, 12, 6687–6706, https://doi.org/10.5194/bg-12-6687-2015, https://doi.org/10.5194/bg-12-6687-2015, 2015
Short summary
Short summary
We combined field, laboratory (sediment-flow-through system) and numerical modeling work to investigate cold seep sediments at Quespos Slide, offshore of Costa Rica. The results demonstrated the efficiency of the benthic methane filter and provided an estimate for its response time (ca. 170 days) to changes in fluid fluxes.
A. Lichtschlag, D. Donis, F. Janssen, G. L. Jessen, M. Holtappels, F. Wenzhöfer, S. Mazlumyan, N. Sergeeva, C. Waldmann, and A. Boetius
Biogeosciences, 12, 5075–5092, https://doi.org/10.5194/bg-12-5075-2015, https://doi.org/10.5194/bg-12-5075-2015, 2015
A. W. Dale, S. Sommer, U. Lomnitz, I. Montes, T. Treude, V. Liebetrau, J. Gier, C. Hensen, M. Dengler, K. Stolpovsky, L. D. Bryant, and K. Wallmann
Biogeosciences, 12, 1537–1559, https://doi.org/10.5194/bg-12-1537-2015, https://doi.org/10.5194/bg-12-1537-2015, 2015
J. Friedrich, F. Janssen, D. Aleynik, H. W. Bange, N. Boltacheva, M. N. Çagatay, A. W. Dale, G. Etiope, Z. Erdem, M. Geraga, A. Gilli, M. T. Gomoiu, P. O. J. Hall, D. Hansson, Y. He, M. Holtappels, M. K. Kirf, M. Kononets, S. Konovalov, A. Lichtschlag, D. M. Livingstone, G. Marinaro, S. Mazlumyan, S. Naeher, R. P. North, G. Papatheodorou, O. Pfannkuche, R. Prien, G. Rehder, C. J. Schubert, T. Soltwedel, S. Sommer, H. Stahl, E. V. Stanev, A. Teaca, A. Tengberg, C. Waldmann, B. Wehrli, and F. Wenzhöfer
Biogeosciences, 11, 1215–1259, https://doi.org/10.5194/bg-11-1215-2014, https://doi.org/10.5194/bg-11-1215-2014, 2014
S. Krause, P. Steeb, C. Hensen, V. Liebetrau, A. W. Dale, M. Nuzzo, and T. Treude
Biogeosciences, 11, 507–523, https://doi.org/10.5194/bg-11-507-2014, https://doi.org/10.5194/bg-11-507-2014, 2014
J. Felden, A. Lichtschlag, F. Wenzhöfer, D. de Beer, T. Feseker, P. Pop Ristova, G. de Lange, and A. Boetius
Biogeosciences, 10, 3269–3283, https://doi.org/10.5194/bg-10-3269-2013, https://doi.org/10.5194/bg-10-3269-2013, 2013
V. J. Bertics, C. R. Löscher, I. Salonen, A. W. Dale, J. Gier, R. A. Schmitz, and T. Treude
Biogeosciences, 10, 1243–1258, https://doi.org/10.5194/bg-10-1243-2013, https://doi.org/10.5194/bg-10-1243-2013, 2013
A. W. Dale, V. J. Bertics, T. Treude, S. Sommer, and K. Wallmann
Biogeosciences, 10, 629–651, https://doi.org/10.5194/bg-10-629-2013, https://doi.org/10.5194/bg-10-629-2013, 2013
Related subject area
Biogeochemistry: Coastal Ocean
Hypoxia also occurs in small highly turbid estuaries: the example of the Charente (Bay of Biscay)
Seasonality and response of ocean acidification and hypoxia to major environmental anomalies in the southern Salish Sea, North America (2014–2018)
Oceanographic processes driving low-oxygen conditions inside Patagonian fjords
Above- and belowground plant mercury dynamics in a salt marsh estuary in Massachusetts, USA
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
Quantification and mitigation of bottom trawling impacts on sedimentary organic carbon stocks in the North Sea
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
Ocean alkalinity enhancement using sodium carbonate salts does not impact Fe dynamics in a mesocosm experiment
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
Picoplanktonic methane production in eutrophic surface waters
Influence of Ocean Alkalinity Enhancement with Olivine or Steel Slag on a Coastal Plankton Community in Tasmania
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
Vertical mixing alleviates autumnal oxygen deficiency in the central North Sea
Intra-scenario variability of trends and controls of near-bed oxygen concentration on the Northwest European Continental Shelf under climate change
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
Sediment quality assessment in an industrialized Greek coastal marine area (western Saronikos Gulf)
Limits and CO2 equilibration of near-coast alkalinity enhancement
Role of phosphorus in the seasonal deoxygenation of the East China Sea shelf
Interannual variability of the initiation of the phytoplankton growing period in two French coastal ecosystems
Spatio-temporal distribution, photoreactivity and environmental control of dissolved organic matter in the sea-surface microlayer of the eastern marginal seas of China
Metabolic alkalinity release from large port facilities (Hamburg, Germany) and impact on coastal carbon storage
A Numerical reassessment of the Gulf of Mexico carbon system in connection with the Mississippi River and global ocean
Observed and projected global warming pressure on coastal hypoxia
Benthic alkalinity fluxes from coastal sediments of the Baltic and North seas: comparing approaches and identifying knowledge gaps
Investigating the effect of nickel concentration on phytoplankton growth to assess potential side-effects of ocean alkalinity enhancement
Unprecedented summer hypoxia in southern Cape Cod Bay: an ecological response to regional climate change?
Interannual variabilities, long-term trends, and regulating factors of low-oxygen conditions in the coastal waters off Hong Kong
Causes of the extensive hypoxia in the Gulf of Riga in 2018
Trawling effects on biogeochemical processes are mediated by fauna in high-energy biogenic-reef-inhabited coastal sediments
Drought recorded by Ba∕Ca in coastal benthic foraminifera
A nitrate budget of the Bohai Sea based on an isotope mass balance model
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Lucas Porz, Wenyan Zhang, Nils Gerrit Christiansen, Jan Kossack, Ute Daewel, and Corinna Schrum
EGUsphere, https://doi.org/10.5194/egusphere-2024-399, https://doi.org/10.5194/egusphere-2024-399, 2024
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
David González-Santana, María Segovia, Melchor González-Dávila, Librada Ramírez, Aridane G. González, Leonardo J. Pozzo, Veronica Arnone, Victor Vázquez, Ulf Riebesell, and J. Magdalena Santana-Casiano
EGUsphere, https://doi.org/10.5194/egusphere-2023-2868, https://doi.org/10.5194/egusphere-2023-2868, 2023
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Sandy E. Tenorio and Laura Farías
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-185, https://doi.org/10.5194/bg-2023-185, 2023
Revised manuscript accepted for BG
Short summary
Short summary
Time series studies show that CH4 is highly dynamic on the coastal ocean surface and that planktonic communities are linked to CH4 accumulation as is found in coastal upwelling off Central Chile. We’ve identified the crucial role of picoplankton (>3μm) in CH4 recycling, especially with the addition of methylated substrates (TMA and MPn) during upwelling and non-upwelling periods. These insights improve understanding of surface ocean CH4 recycling, aiding accurate CH4 emissions estimates.
Jiaying A. Guo, Robert F. Strzepek, Kerrie M. Swadling, Ashley T. Townsend, and Lennart T. Bach
EGUsphere, https://doi.org/10.5194/egusphere-2023-2120, https://doi.org/10.5194/egusphere-2023-2120, 2023
Short summary
Short summary
Ocean alkalinity enhancement (OAE) aims to increase atmospheric CO2 sequestration in the oceans by spreading ground alkaline materials into the ocean. To assess the environmental impacts of OAE, we used 53 L microcosms to test how coastal plankton communities respond to OAE with olivine or steel slag as alkalinity sources. Overall, steel slag is much more efficient for CO2 removal than olivine and appears to be induce less changes in the phytoplankton and zooplankton communities.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Charlotte Williams, Tom Hull, Matthew Palmer, Claire Mahaffey, Naomi Greenwood, Jan Kaiser, and Matthew Toberman
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-100, https://doi.org/10.5194/bg-2023-100, 2023
Revised manuscript accepted for BG
Short summary
Short summary
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 reach ecologically low levels.
Giovanni Galli, Sarah Wakelin, James Harle, Jason Holt, and Yuri Artioli
EGUsphere, https://doi.org/10.5194/egusphere-2023-1049, https://doi.org/10.5194/egusphere-2023-1049, 2023
Short summary
Short summary
In this work we looked at the projected change in bottom water oxygen content in an ensemble of ocean climate change models of the North Western European Shelf. What emerged is that, 1. oxygen decreases in all models, 2. in the models with the most warming, a change in circulation patterns is tied to the emergence of low oxygen hotspots in the Eastern North Sea, and, 3. in relatively shallow coastal areas increasing in primary production partially mitigates oxygen decline.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Georgia Filippi, Manos Dassenakis, Vasiliki Paraskevopoulou, and Konstantinos Lazogiannis
Biogeosciences, 20, 163–189, https://doi.org/10.5194/bg-20-163-2023, https://doi.org/10.5194/bg-20-163-2023, 2023
Short summary
Short summary
The pollution of the western Saronikos Gulf from heavy metals has been examined through the study of marine sediment cores. It is a deep gulf (maximum depth 440 m) near Athens affected by industrial and volcanic activity. Eight cores were received from various stations and depths and analysed for their heavy metal content and geochemical characteristics. The results were evaluated by using statistical methods, environmental indicators and comparisons with old data.
Jing He and Michael D. Tyka
Biogeosciences, 20, 27–43, https://doi.org/10.5194/bg-20-27-2023, https://doi.org/10.5194/bg-20-27-2023, 2023
Short summary
Short summary
Recently, ocean alkalinity enhancement (OAE) has gained interest as a scalable way to address the urgent need for negative CO2 emissions. In this paper we examine the capacity of different coastlines to tolerate alkalinity enhancement and the time scale of CO2 uptake following the addition of a given quantity of alkalinity. The results suggest that OAE has significant potential and identify specific favorable and unfavorable coastlines for its deployment.
Arnaud Laurent, Haiyan Zhang, and Katja Fennel
Biogeosciences, 19, 5893–5910, https://doi.org/10.5194/bg-19-5893-2022, https://doi.org/10.5194/bg-19-5893-2022, 2022
Short summary
Short summary
The Changjiang is the main terrestrial source of nutrients to the East China Sea (ECS). Nutrient delivery to the ECS has been increasing since the 1960s, resulting in low oxygen (hypoxia) during phytoplankton decomposition in summer. River phosphorus (P) has increased less than nitrogen, and therefore, despite the large nutrient delivery, phytoplankton growth can be limited by the lack of P. Here, we investigate this link between P limitation, phytoplankton production/decomposition, and hypoxia.
Coline Poppeschi, Guillaume Charria, Anne Daniel, Romaric Verney, Peggy Rimmelin-Maury, Michaël Retho, Eric Goberville, Emilie Grossteffan, and Martin Plus
Biogeosciences, 19, 5667–5687, https://doi.org/10.5194/bg-19-5667-2022, https://doi.org/10.5194/bg-19-5667-2022, 2022
Short summary
Short summary
This paper aims to understand interannual changes in the initiation of the phytoplankton growing period (IPGP) in the current context of global climate changes over the last 20 years. An important variability in the timing of the IPGP is observed with a trend towards a later IPGP during this last decade. The role and the impact of extreme events (cold spells, floods, and wind burst) on the IPGP is also detailed.
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
Short summary
Short summary
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.
Mona Norbisrath, Johannes Pätsch, Kirstin Dähnke, Tina Sanders, Gesa Schulz, Justus E. E. van Beusekom, and Helmuth Thomas
Biogeosciences, 19, 5151–5165, https://doi.org/10.5194/bg-19-5151-2022, https://doi.org/10.5194/bg-19-5151-2022, 2022
Short summary
Short summary
Total alkalinity (TA) regulates the oceanic storage capacity of atmospheric CO2. TA is also metabolically generated in estuaries and influences coastal carbon storage through its inflows. We used water samples and identified the Hamburg port area as the one with highest TA generation. Of the overall riverine TA load, 14 % is generated within the estuary. Using a biogeochemical model, we estimated potential effects on the coastal carbon storage under possible anthropogenic and climate changes.
Le Zhang and Z. George Xue
Biogeosciences, 19, 4589–4618, https://doi.org/10.5194/bg-19-4589-2022, https://doi.org/10.5194/bg-19-4589-2022, 2022
Short summary
Short summary
We adopt a high-resolution carbon model for the Gulf of Mexico (GoM) and calculate the decadal trends of important carbon system variables in the GoM from 2001 to 2019. The GoM surface CO2 values experienced a steady increase over the past 2 decades, and the ocean surface pH is declining. Although carbonate saturation rates remain supersaturated with aragonite, they show a slightly decreasing trend. The northern GoM is a stronger carbon sink than we thought.
Michael M. Whitney
Biogeosciences, 19, 4479–4497, https://doi.org/10.5194/bg-19-4479-2022, https://doi.org/10.5194/bg-19-4479-2022, 2022
Short summary
Short summary
Coastal hypoxia is a major environmental problem of increasing severity. The 21st-century projections analyzed indicate global coastal waters will warm and experience rapid declines in oxygen. The forecasted median coastal trends for increasing sea surface temperature and decreasing oxygen capacity are 48 % and 18 % faster than the rates observed over the last 4 decades. Existing hypoxic areas are expected to worsen, and new hypoxic areas likely will emerge under these warming-related pressures.
Bryce Van Dam, Nele Lehmann, Mary A. Zeller, Andreas Neumann, Daniel Pröfrock, Marko Lipka, Helmuth Thomas, and Michael Ernst Böttcher
Biogeosciences, 19, 3775–3789, https://doi.org/10.5194/bg-19-3775-2022, https://doi.org/10.5194/bg-19-3775-2022, 2022
Short summary
Short summary
We quantified sediment–water exchange at shallow sites in the North and Baltic seas. We found that porewater irrigation rates in the former were approximately twice as high as previously estimated, likely driven by relatively high bioirrigative activity. In contrast, we found small net fluxes of alkalinity, ranging from −35 µmol m−2 h−1 (uptake) to 53 µmol m−2 h−1 (release). We attribute this to low net denitrification, carbonate mineral (re-)precipitation, and sulfide (re-)oxidation.
Jiaying Abby Guo, Robert Strzepek, Anusuya Willis, Aaron Ferderer, and Lennart Thomas Bach
Biogeosciences, 19, 3683–3697, https://doi.org/10.5194/bg-19-3683-2022, https://doi.org/10.5194/bg-19-3683-2022, 2022
Short summary
Short summary
Ocean alkalinity enhancement is a CO2 removal method with significant potential, but it can lead to a perturbation of the ocean with trace metals such as nickel. This study tested the effect of increasing nickel concentrations on phytoplankton growth and photosynthesis. We found that the response to nickel varied across the 11 phytoplankton species tested here, but the majority were rather insensitive. We note, however, that responses may be different under other experimental conditions.
Malcolm E. Scully, W. Rockwell Geyer, David Borkman, Tracy L. Pugh, Amy Costa, and Owen C. Nichols
Biogeosciences, 19, 3523–3536, https://doi.org/10.5194/bg-19-3523-2022, https://doi.org/10.5194/bg-19-3523-2022, 2022
Short summary
Short summary
For two consecutive summers, the bottom waters in southern Cape Cod Bay became severely depleted of dissolved oxygen. Low oxygen levels in bottom waters have never been reported in this area before, and this unprecedented occurrence is likely the result of a new algae species that recently began blooming during the late-summer months. We present data suggesting that blooms of this new species are the result of regional climate change including warmer waters and changes in summer winds.
Zheng Chen, Bin Wang, Chuang Xu, Zhongren Zhang, Shiyu Li, and Jiatang Hu
Biogeosciences, 19, 3469–3490, https://doi.org/10.5194/bg-19-3469-2022, https://doi.org/10.5194/bg-19-3469-2022, 2022
Short summary
Short summary
Deterioration of low-oxygen conditions in the coastal waters off Hong Kong was revealed by monitoring data over two decades. The declining wind forcing and the increasing nutrient input contributed significantly to the areal expansion and intense deterioration of low-oxygen conditions. Also, the exacerbated eutrophication drove a shift in the dominant source of organic matter from terrestrial inputs to in situ primary production, which has probably led to an earlier onset of hypoxia in summer.
Stella-Theresa Stoicescu, Jaan Laanemets, Taavi Liblik, Māris Skudra, Oliver Samlas, Inga Lips, and Urmas Lips
Biogeosciences, 19, 2903–2920, https://doi.org/10.5194/bg-19-2903-2022, https://doi.org/10.5194/bg-19-2903-2022, 2022
Short summary
Short summary
Coastal basins with high input of nutrients often suffer from oxygen deficiency. In summer 2018, the extent of oxygen depletion was exceptional in the Gulf of Riga. We analyzed observational data and found that extensive oxygen deficiency appeared since the water layer close to the seabed, where oxygen is consumed, was separated from the surface layer. The problem worsens if similar conditions restricting vertical transport of oxygen occur more frequently in the future.
Justin C. Tiano, Jochen Depestele, Gert Van Hoey, João Fernandes, Pieter van Rijswijk, and Karline Soetaert
Biogeosciences, 19, 2583–2598, https://doi.org/10.5194/bg-19-2583-2022, https://doi.org/10.5194/bg-19-2583-2022, 2022
Short summary
Short summary
This study gives an assessment of bottom trawling on physical, chemical, and biological characteristics in a location known for its strong currents and variable habitats. Although trawl gears only removed the top 1 cm of the seabed surface, impacts on reef-building tubeworms significantly decreased carbon and nutrient cycling. Lighter trawls slightly reduced the impact on fauna and nutrients. Tubeworms were strongly linked to biogeochemical and faunal aspects before but not after trawling.
Inda Brinkmann, Christine Barras, Tom Jilbert, Tomas Næraa, K. Mareike Paul, Magali Schweizer, and Helena L. Filipsson
Biogeosciences, 19, 2523–2535, https://doi.org/10.5194/bg-19-2523-2022, https://doi.org/10.5194/bg-19-2523-2022, 2022
Short summary
Short summary
The concentration of the trace metal barium (Ba) in coastal seawater is a function of continental input, such as riverine discharge. Our geochemical records of the severely hot and dry year 2018, and following wet year 2019, reveal that prolonged drought imprints with exceptionally low Ba concentrations in benthic foraminiferal calcium carbonates of coastal sediments. This highlights the potential of benthic Ba / Ca to trace past climate extremes and variability in coastal marine records.
Shichao Tian, Birgit Gaye, Jianhui Tang, Yongming Luo, Wenguo Li, Niko Lahajnar, Kirstin Dähnke, Tina Sanders, Tianqi Xiong, Weidong Zhai, and Kay-Christian Emeis
Biogeosciences, 19, 2397–2415, https://doi.org/10.5194/bg-19-2397-2022, https://doi.org/10.5194/bg-19-2397-2022, 2022
Short summary
Short summary
We constrain the nitrogen budget and in particular the internal sources and sinks of nitrate in the Bohai Sea by using a mass-based and dual stable isotope approach based on δ15N and δ18O of nitrate. Based on available mass fluxes and isotope data an updated nitrogen budget is proposed. Compared to previous estimates, it is more complete and includes the impact of the interior cycle (nitrification) on the nitrate pool. The main external nitrogen sources are rivers contributing 19.2 %–25.6 %.
Cited articles
Algar, C. K. and Vallino, J. J.: Predicting microbial nitrate reduction pathways in coastal sediments, Aquat. Microb. Ecol., 71, 223–238, 2014.
An, S. and Gardner, W. S.: Dissimilatory nitrate reduction to ammonium (DNRA) as a nitrogen link, versus denitrification as a sink in a shallow estuary (Laguna Madre/Baffin Bay, Texas), Mar. Ecol. Prog. Ser., 237, 41–50, 2002.
Bernhard, J. M., Buck, K. R., Farmer, M. A., and Bowser, S. S.: The Santa Barbara Basin is a symbiosis oasis, Nature, 403, 77–80, 2000.
Bernhard, J. M., Visscher, P. T., and Bowser, S. S.: Submillimeter life positions of bacteria, protists, and metazoans in laminated sediments of the Santa Barbara Basin, Limnol. Oceanogr., 48, 813–828, 2003.
Bernhard, J. M., Casciotti, K. L., McIlvin, M. R., Beaudoin, D. J., Visscher, P. T., and Edgcomb, V. P.: Potential importance of physiologically diverse benthic foraminifera in sedimentary nitrate storage and respiration, J. Geophys. Res.-Biogeo., 117, https://doi.org/10.1029/2012JG001949, 2012.
Bograd, S. J., Schwing, F. B., Castro, C. G., and Timothy, D. A.: Bottom water renewal in the Santa Barbara Basin, J. Geophys. Res.-Oceans, 107, 3216, https://doi.org/10.1029/2001JC001291, 2002.
Bonaglia, S., Nascimento, F. A., Bartoli, M., Klawonn, I., and Brüchert, V.: Meiofauna increases bacterial denitrification in marine sediments, Nat. Commun., 5, 5133, https://doi.org/10.1038/ncomms6133, 2014.
Boudreau, B. P. and Jorgensen, B. B.: The benthic boundary layer: Transport processes and biogeochemistry, ISBN 9780195118810, 2001.
Bourbonnais, A., Letscher, R. T., Bange, H. W., Echevin, V., Larkum, J., Mohn, J., Yoshida, N., and Altabet, M. A.: N2O production and consumption from stable isotopic and concentration data in the Peruvian coastal upwelling system, Global Biogeochem. Cy., 31, 678–698, 2017.
Bremner, J.: Biogenic sediments on the South West African continental margin, https://api.semanticscholar.org/CorpusID:133192933 (last access: 1 February 2024), 1981.
Brüchert, V., Jørgensen, B. B., Neumann, K., Riechmann, D., Schlösser, M., and Schulz, H.: Regulation of bacterial sulfate reduction and hydrogen sulfide fluxes in the central Namibian coastal upwelling zone, Geochim. Cosmochim. Ac., 67, 4505–4518, 2003.
Caffrey, J. M., Bonaglia, S., and Conley, D. J.: Short exposure to oxygen and sulfide alter nitrification, denitrification, and DNRA activity in seasonally hypoxic estuarine sediments, FEMS Microb. Lett., 366, fny288, https://doi.org/10.1093/femsle/fny288, 2019.
Canfield, D. E.: Reactive iron in marine sediments, Geochim. Cosmochim. Ac., 53, 619–632, 1989.
Canfield, D. E., Stewart, F. J., Thamdrup, B., De Brabandere, L., Dalsgaard, T., Delong, E. F., Revsbech, N. P., and Ulloa, O.: A cryptic sulfur cycle in oxygen-minimum–zone waters off the Chilean coast, Science, 330, 1375–1378, 2010.
Charoenpong, C. N., Bristow, L. A., and Altabet, M. A.: A continuous flow isotope ratio mass spectrometry method for high precision determination of dissolved gas ratios and isotopic composition, Limnol. Oceanogr.-Meth., 12, 323–337, 2014.
Cline, J. D.: Spectrophometric determination of hydrogen sulfide in natural waters, Limnol. Oceanogr., 14, 454–458, 1969.
Dale, A. W., Sommer, S., Bohlen, L., Treude, T., Bertics, V. J., Bange, H. W., Pfannkuche, O., Schorp, T., Mattsdotter, M., and Wallmann, K.: Rates and regulation of nitrogen cycling in seasonally hypoxic sediments during winter (Boknis Eck, SW Baltic Sea): Sensitivity to environmental variables, Estuar. Coast. Shelf S., 95, 14–28, 2011.
Dale, A. W., Bertics, V. J., Treude, T., Sommer, S., and Wallmann, K.: Modeling benthic–pelagic nutrient exchange processes and porewater distributions in a seasonally hypoxic sediment: evidence for massive phosphate release by Beggiatoa?, Biogeosciences, 10, 629–651, https://doi.org/10.5194/bg-10-629-2013, 2013.
Dale, A. W., Sommer, S., Ryabenko, E., Noffke, A., Bohlen, L., Wallmann, K., Stolpovsky, K., Greinert, J., and Pfannkuche, O.: Benthic nitrogen fluxes and fractionation of nitrate in the Mauritanian oxygen minimum zone (Eastern Tropical North Atlantic), Geochim. Cosmochim. Ac., 134, 234–256, 2014.
Dale, A. W., Sommer, S., Lomnitz, U., Montes, I., Treude, T., Liebetrau, V., Gier, J., Hensen, C., Dengler, M., Stolpovsky, K., Bryant, L. D., and Wallmann, K.: Organic carbon production, mineralisation and preservation on the Peruvian margin, Biogeosciences, 12, 1537–1559, https://doi.org/10.5194/bg-12-1537-2015, 2015.
Dale, A. W., Sommer, S., Lomnitz, U., Bourbonnais, A., and Wallmann, K.: Biological nitrate transport in sediments on the Peruvian margin mitigates benthic sulfide emissions and drives pelagic N loss during stagnation events, Deep-Sea Res. Pt. I, 112, 123–136, 2016.
De Brabandere, L., Bonaglia, S., Kononets, M. Y., Viktorsson, L., Stigebrandt, A., Thamdrup, B., and Hall, P. O.: Oxygenation of an anoxic fjord basin strongly stimulates benthic denitrification and DNRA, Biogeochemistry, 126, 131–152, 2015.
Emery, K., Hülsemann, J., and Rodolfo, K.: Influence of turbidity currents upon basin waters, Limnol. Oceanogr., 7, 439–446, 1962.
Emmer, E. and Thunell, R. C.: Nitrogen isotope variations in Santa Barbara Basin sediments: Implications for denitrification in the eastern tropical North Pacific during the last 50 000 years, Paleoceanography, 15, 377–387, 2000.
Fossing, H., Gallardo, V. A., Jørgensen, B. B., Hüttel, M., Nielsen, L. P., Schulz, H., Canfield, D. E., Forster, S., Glud, R. N., and Gundersen, J. K.: Concentration and transport of nitrate by the mat-forming sulphur bacterium Thioploca, Nature, 374, 713–715, 1995.
García-Robledo, E., Corzo, A., and Papaspyrou, S.: A fast and direct spectrophotometric method for the sequential determination of nitrate and nitrite at low concentrations in small volumes, Mar. Chem., 162, 30–36, 2014.
Gier, J., Sommer, S., Löscher, C. R., Dale, A. W., Schmitz, R. A., and Treude, T.: Nitrogen fixation in sediments along a depth transect through the Peruvian oxygen minimum zone, Biogeosciences, 13, 4065–4080, https://doi.org/10.5194/bg-13-4065-2016, 2016.
Glud, R. N., Gundersen, J. K., and Ramsing, N. B.: Electrochemical and optical oxygen microsensors for in situ measurements, in: In situ monitoring of aquatic systems: Chemical analysis and speciation, edited by: Buffle, J., and Horvai, G., Wiley, ISBN 0471489794, 2000.
Goericke, R., Bograd, S. J., and Grundle, D. S.: Denitrification and flushing of the Santa Barbara Basin bottom waters, Deep-Sea Res. Pt. II, 112, 53–60, 2015.
Grasshoff, K., Ehrhardt, M., and Kremling, K.: Methods of seawater analysis, Wiley-VCH Verlag GmbH, Weinheim, 632 pp., 1999.
Gundersen, J. K. and Jørgensen, B. B.: Microstructure of diffusive boundary layers and the oxygen uptake of the sea floor, Nature, 345, 604–607, 1990.
Hall, P. O. J. and Aller, R. C.: Rapid small-volume flow injection analysis for SCO2 and NH
Hardison, A. K., Algar, C. K., Giblin, A. E., and Rich, J. J.: Influence of organic carbon and nitrate loading on partitioning between dissimilatory nitrate reduction to ammonium (DNRA) and N2 production, Geochim. Cosmochim. Ac., 164, 146–160, 2015.
Harris, D., Horwáth, W. R., and Van Kessel, C.: Acid fumigation of soils to remove carbonates prior to total organic carbon or carbon-13 isotopic analysis, Soil Sci. Soc. Am. J., 65, 1853–1856, 2001.
Hermans, M., Lenstra, W. K., Hidalgo-Martinez, S., van Helmond, N. A., Witbaard, R., Meysman, F. J., Gonzalez, S., and Slomp, C. P.: Abundance and biogeochemical impact of cable bacteria in Baltic Sea sediments, Environ. Sci. Technol., 53, 7494–7503, 2019.
Hossain, M., Bhattacharya, P., Frape, S. K., Jacks, G., Islam, M. M., Rahman, M. M., von Brömssen, M., Hasan, M. A., and Ahmed, K. M.: Sediment color tool for targeting arsenic-safe aquifers for the installation of shallow drinking water tubewells, Sci. Total Environ., 493, 615–625, 2014.
Huettel, M., Forster, S., Kloser, S., and Fossing, H.: Vertical migration in the sediment-dwelling sulfur bacteria Thioploca spp. in overcoming diffusion limitations, Appl. Environ. Microb., 62, 1863–1872, 1996.
Hylén, A., Bonaglia, S., Robertson, E., Marzocchi, U., Kononets, M., and Hall, P. O.: Enhanced benthic nitrous oxide and ammonium production after natural oxygenation of long anoxic sediments, Limnol. Oceanogr., 67, 419–433, 2022.
Høgslund, S., Revsbech, N. P., Kuenen, J. G., Jørgensen, B. B., Gallardo, V. A., v. d. Vossenberg, J., Nielsen, J. L., Holmkvist, L., Arning, E. T., and Nielsen, L. P.: Physiology and behaviour of marine Thioploca, ISME J., 3, 647–657, 2009.
Jeroschewsky, P., Steuckart, C., and Kuehl, M.: An amperometric microsensor for the determination af H2S in aquatic environments, Anal. Chem., 68, 4351–4357, 1996.
Jørgensen, B.: Distribution of colorless sulfur bacteria (Beggiatoa spp.) in a coastal marine sediment, Mar. Biol., 41, 19–28, 1977.
Jørgensen, B. B.: A comparison of methods for the quantification of bacterial sulphate reduction in coastal marine sediments: I. Measurements with radiotracer techniques, Geomicrobiol. J., 1, 11–27, 1978.
Jørgensen, B. B. and Nelson, D. C.: Sulfide oxidation in marine sediments: Geochemistry meets microbiology, Geol. Soc. Am. Spec. Pap., 379, 63–81, 2004.
Kallmeyer, J., Ferdelman, T. G., Weber, A., Fossing, H., and Jørgensen, B. B.: A cold chromium distillation procedure for radiolabeled sulfide applied to sulfate reduction measurements, Limnol. Oceanogr.-Meth., 2, 171–180, 2004.
Kamp, A., de Beer, D., Nitsch, J. L., Lavik, G., and Stief, P.: Diatoms respire nitrate to survive dark and anoxic conditions, Proceedings of the National Academy of Sciences, 108, 5649–5654, 2011.
Kamp, A., Høgslund, S., Risgaard-Petersen, N., and Stief, P.: Nitrate storage and dissimilatory nitrate reduction by eukaryotic microbes, Fron. Microbiol., 6, 1492, https://doi.org/10.3389/fmicb.2015.01492, 2015.
Kessler, A. J., Wawryk, M., Marzocchi, U., Roberts, K. L., Wong, W. W., Risgaard Petersen, N., Meysman, F. J., Glud, R. N., and Cook, P. L.: Cable bacteria promote DNRA through iron sulfide dissolution, Limnol. Oceanogr., 64, 1228–1238, 2019.
Kjeldsen, K. U., Schreiber, L., Thorup, C. A., Boesen, T., Bjerg, J. T., Yang, T., Dueholm, M. S., Larsen, S., Risgaard-Petersen, N., and Nierychlo, M.: On the evolution and physiology of cable bacteria, P. Natl. Acad. Sci. USA, 116, 19116–19125, 2019.
Kononets, M., Tengberg, A., Nilsson, M., Ekeroth, N., Hylén, A., Robertson, E. K., Van De Velde, S., Bonaglia, S., Rütting, T., and Blomqvist, S.: In situ incubations with the Gothenburg benthic chamber landers: Applications and quality control, J. Mar. Syst., 214, 103475, https://doi.org/10.1016/j.jmarsys.2020.103475, 2021.
Kraft, B., Tegetmeyer, H. E., Sharma, R., Klotz, M. G., Ferdelman, T. G., Hettich, R. L., Geelhoed, J. S., and Strous, M.: The environmental controls that govern the end product of bacterial nitrate respiration, Science, 345, 676–679, 2014.
Kuwabara, J. S., van Geen, A., McCorkle, D. C., and Bernhard, J. M.: Dissolved sulfide distributions in the water column and sediment pore waters of the Santa Barbara Basin, Geochim. Cosmochim. Ac., 63, 2199–2209, 1999.
Lazo-Murphy, B. M., Larson, S., Staines, S., Bruck, H., McHenry, J., Bourbonnais, A., and Peng, X.: Nitrous oxide production and isotopomer composition by fungi isolated from salt marsh sediments, Front. Mar. Sci., 9, 1098508, https://doi.org/10.3389/fmars.2022.1098508, 2022.
Levin, L. A., Gutierrez, D., Rathburn, A. E., Neira, C., Sellanes, J., Munoz, P., Gallardo, V. A., and Salamance, M.: Bethic processes on the Peru margin: a transect across the oxygen minimum zone during the 1997-98 El Nino, Prog. Oceanog., 53, 1–27, 2002.
Marchant, H. K., Lavik, G., Holtappels, M., and Kuypers, M. M.: The fate of nitrate in intertidal permeable sediments, PloS one, 9, e104517, https://doi.org/10.1371/journal.pone.0104517, 2014.
Marzocchi, U., Bonaglia, S., van de Velde, S., Hall, P. O., Schramm, A., Risgaard Petersen, N., and Meysman, F. J.: Transient bottom water oxygenation creates a niche for cable bacteria in long term anoxic sediments of the Eastern Gotland Basin, Environ. Microbiol., 20, 3031–3041, 2018.
Marzocchi, U., Trojan, D., Larsen, S., Louise Meyer, R., Peter Revsbech, N., Schramm, A., Peter Nielsen, L., and Risgaard-Petersen, N.: Electric coupling between distant nitrate reduction and sulfide oxidation in marine sediment, ISME Jo., 8, 1682–1690, 2014.
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.
Mortimer, C. H.: The exchange of dissolved substances between mud and water in lakes, J. Ecol., 29, 280–329, 1941.
Mosch, T., Sommer, S., Dengler, M., Noffke, A., Bohlen, L., Pfannkuche, O., Liebetrau, V., and Wallmann, K.: Factors influencing the distribution of epibenthic megafauna across the Peruvian oxygen minimum zone, Deep-Sea Res. Pt. I, 68, 123–135, 2012.
Mußmann, M., Schulz, H. N., Strotmann, B., Kjær, T., Nielsen, L. P., Rosselló Mora, R. A., Amann, R. I., and Jørgensen, B. B.: Phylogeny and distribution of nitrate storing Beggiatoa spp. in coastal marine sediments, Environ. Microbiol., 5, 523–533, 2003.
Myhre, S. E., Pak, D., Borreggine, M., Kennett, J. P., Nicholson, C., Hill, T. M., and Deutsch, C.: Oxygen minimum zone biotic baseline transects for paleoceanographic reconstructions in Santa Barbara Basin, CA, Deep-Sea Res. Pt. II, 150, 118–131, 2018.
Naik, R., Naqvi, S., and Araujo, J.: Anaerobic carbon mineralisation through sulphate reduction in the inner shelf sediments of eastern Arabian Sea, Estuar. Coast., 40, 134–144, 2017.
Noffke, A., Sommer, S., Dale, A., Hall, P., and Pfannkuche, O.: Benthic nutrient fluxes in the Eastern Gotland Basin (Baltic Sea) with particular focus on microbial mat ecosystems, J. Mar. Syst., 158, 1–12, 2016.
Noffke, A., Hensen, C., Sommer, S., Scholz, F., Bohlen, L., Mosch, T., Graco, M., and Wallmann, K.: Benthic iron and phosphorus fluxes across the Peruvian oxygen minimum zone, Limnol. Oceanogr., 57, 851–867, 2012.
Pavlova, G. Y., Tishchenko, P. Y., Volkova, T., Dickson, A., and Wallmann, K.: Intercalibration of Bruevich's method to determine the total alkalinity in seawater, Oceanology, 48, 438–443, 2008.
Peng, X., Ji, Q., Angell, J. H., Kearns, P. J., Yang, H. J., Bowen, J. L., and Ward, B. B.: Long term fertilization alters the relative importance of nitrate reduction pathways in salt marsh sediments, J. Geophys. Res.-Biogeo., 121, 2082–2095, 2016.
Peng, X., Yousavich, D. J., Bourbonnais, A., Wenzhoefer, F., Janssen, F., Treude, T., and Valentine, D. L.: The fate of fixed nitrogen in Santa Barbara Basin sediments during seasonal anoxia, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2023-1498, 2023.
Pfeffer, C., Larsen, S., Song, J., Dong, M., Besenbacher, F., Meyer, R. L., Kjeldsen, K. U., Schreiber, L., Gorby, Y. A., and El-Naggar, M. Y.: Filamentous bacteria transport electrons over centimetre distances, Nature, 491, 218–221, 2012.
Plass, A., Schlosser, C., Sommer, S., Dale, A. W., Achterberg, E. P., and Scholz, F.: The control of hydrogen sulfide on benthic iron and cadmium fluxes in the oxygen minimum zone off Peru, Biogeosciences, 17, 3685–3704, https://doi.org/10.5194/bg-17-3685-2020, 2020.
Porubsky, W., Weston, N., and Joye, S.: Benthic metabolism and the fate of dissolved inorganic nitrogen in intertidal sediments, Eastuar. Coast. Shelf S., 83, 392–402, 2009.
Preisler, A., De Beer, D., Lichtschlag, A., Lavik, G., Boetius, A., and Jørgensen, B. B.: Biological and chemical sulfide oxidation in a Beggiatoa inhabited marine sediment, ISME J., 1, 341–351, 2007.
Prokopenko, M., Hammond, D., Berelson, W., Bernhard, J., Stott, L., and Douglas, R.: Nitrogen cycling in the sediments of Santa Barbara basin and Eastern Subtropical North Pacific: Nitrogen isotopes, diagenesis and possible chemosymbiosis between two lithotrophs (Thioploca and Anammox) – “riding on a glider”, Earth Planet. Sc. Lett., 242, 186–204, 2006.
Qin, Q., Kinnaman, F. S., Gosselin, K. M., Liu, N., Treude, T., and Valentine, D. L.: Seasonality of Water Column Methane Oxidation and Deoxygenation in a Dynamic Marine Environment, Geochim. Cosmochim. Ac., 336, 219–230, https://doi.org/10.1016/j.gca.2022.09.017, 2022.
Raiswell, R. and Canfield, D. E.: The iron biogeochemical cycle past and present, Geochem. Perspec., 1, 1–2, 2012.
Reimers, C. E., Ruttenberg, K. C., Canfield, D. E., Christiansen, M. B., and Martin, J. B.: Porewater pH and authigenic phases formed in the uppermost sediments of Santa Barbara Basin, Geochim. Cosmochim. Acta, 60, 4037–4057, 1996.
Revsbech, N. P. and Jørgensen, B. B.: Microelectrodes: their use in microbial ecology, edited by: Marshall, K. C., Adv. Microb. Ecol., 9, 293–352, https://doi.org/10.1007/978-1-4757-0611-6_7, 1986.
Risgaard-Petersen, N., Langezaal, A. M., Ingvardsen, S., Schmid, M. C., Jetten, M. S. M., Op den Camp, H. J. M., Derksen, J. W. M., Pina-Ochoa, E., Eriksson, S. P., Nielsen, L. P., Revsbech, N. P., Cedhagen, T., and Zwaan van der, G. J.: Evidence for complete denitrification in a benthic foraminifer, Nature, 443, 93–96, 2006.
Robinson, D., Pham, A. L. D., Yousavich, D. J., Janssen, F., Wenzhöfer, F., Arrington, E. C., Gosselin, K. M., Sandoval-Belmar, M., Mar, M., Valentine, D. L., Bianchi, D., and Treude, T.: Iron “ore” nothing: benthic iron fluxes from the oxygen-deficient Santa Barbara Basin enhance phytoplankton productivity in surface waters, Biogeosciences, 21, 773–788, https://doi.org/10.5194/bg-21-773-2024, 2024.
Sayama, M.: Presence of nitrate-accumulating sulfur bacteria and their influence on nitrogen cycling in a shallow coastal marine sediment, Appl. Environ. Microb., 67, 3481–3487, 2001.
Schauer, R., Risgaard-Petersen, N., Kjeldsen, K. U., Tataru Bjerg, J. J., B Jørgensen, B., Schramm, A., and Nielsen, L. P.: Succession of cable bacteria and electric currents in marine sediment, ISME J., 8, 1314–1322, 2014.
Schroller-Lomnitz, U., Hensen, C., Dale, A. W., Scholz, F., Clemens, D., Sommer, S., Noffke, A., and Wallmann, K.: Dissolved benthic phosphate, iron and carbon fluxes in the Mauritanian upwelling system and implications for ongoing deoxygenation, Deep-Sea Res. Pt. I, 143, 70–84, 2019.
Schulz, H. N. and Schulz, H. D.: Large sulfur bacteria and the formation of phosphorite, Science, 307, 416–418, 2005.
Schulz, H. N., Jorgensen, B. B., Fossing, H. A., and Ramsing, N. B.: Community structure of filamentous, sheath-building sulfur bacteria, Thioploca spp., off the coast of Chile, Appl. Environ. Microb., 62, 1855–1862, 1996.
Schulz, H. N., Brinkhoff, T., Ferdelman, T. G., Hernández Mariné, M., Teske, A., and Jørgensen, B. B.: Dense populations of a giant sulfur bacterium in Namibian shelf sediments, Science, 284, 493–495, 1999.
Seitaj, D., Schauer, R., Sulu-Gambari, F., Hidalgo-Martinez, S., Malkin, S. Y., Burdorf, L. D., Slomp, C. P., and Meysman, F. J.: Cable bacteria generate a firewall against euxinia in seasonally hypoxic basins, P. Natl. Acad. Sci. USA, 112, 13278–13283, 2015.
Sholkovitz, E.: Interstitial water chemistry of the Santa Barbara Basin sediments, Geochim. Cosmochim. Ac., 37, 2043-2073, 1973.
Sholkovitz, E. R. and Gieskes, J. M.: A Physical chemical study of the flushing of the santa barbara basin1, Limnol. Oceanogr., 16, 479–489, 1971.
Sigman, D. M., Robinson, R., Knapp, A., Van Geen, A., McCorkle, D., Brandes, J., and Thunell, R.: Distinguishing between water column and sedimentary denitrification in the Santa Barbara Basin using the stable isotopes of nitrate, Geochem. Geophy. Geosy., 4, https://doi.org/10.1029/2002GC000384, 2003.
Sommer, S., Gier, J., Treude, T., Lomnitz, U., Dengler, M., Cardich, J., and Dale, A. W.: Depletion of oxygen, nitrate and nitrite in the Peruvian oxygen minimum zone cause an imbalance of benthic nitrogen fluxes, Deep-Sea Res. Pt. I, 112, 113–122, 2016.
Stramma, L., Johnson, G. C., Sprintall, J., and Mohrholz, V.: Expanding oxygen-minimum zones in the tropical oceans, Science, 320, 655–658, 2008.
Sverdrup, H. and Allen, W.: Distribution of diatoms in relation to the character of water masses and currents off Southern California in 1938, J. Mar. Res., 2, 131–144, 1939.
Thunell, R. C.: Particle fluxes in a coastal upwelling zone: sediment trap results from Santa Barbara Basin, California, Deep-Sea Res. Pt. II, 45, 1863–1884, 1998.
Tiedje, J. M., Sexstone, A. J., Myrold, D. D., and Robinson, J. A.: Denitrification: ecological niches, competition and survival, Antonie van Leeuwenhoek, 48, 569–583, 1983.
Treude, T.: Biogeochemical reactions in marine sediments underlying anoxic water bodies, in: Anoxia: Paleontological Strategies and Evidence for Eukaryote Survival, edited by: Altenbach, A., Bernhard, J., and Seckbach, J., Cellular Origins, Life in Extreme Habitats and Astrobiology (COLE) Book Series, Springer, Dordrecht, 18–38, 2011.
Treude, T., Smith, C. R., Wenzhoefer, F., Carney, E., Bernardino, A. F., Hannides, A. K., Krueger, M., and Boetius, A.: Biogeochemistry of a deep-sea whale fall: sulfate reduction, sulfide efflux and methanogenesis, Mar. Ecol. Prog. Ser., 382, 1–21, 2009.
Treude, T., Hamdan, L. J., Lemieux, S., Dale, A. W., and Sommer, S.: Rapid sulfur cycling in sediments from the Peruvian oxygen minimum zone featuring simultaneous sulfate reduction and sulfide oxidation, Limnol. Oceanogr., 66, 2661–2671, 2021.
Treude, T. and Valentine, D. L.: Porewater geochemistry of sediments collected Fall 2019 in the Santa Barbara Basin using ROV Jason during R/V Atlantis cruise AT42-19 (Version 1) [data set], Biological and Chemical Oceanography Data Management Office (BCO-DMO). https://doi.org/10.26008/1912/BCO-DMO.867007.1, 2022a.
Treude, T. and Valentine, D. L.: Porosity and density of sediments collected Fall 2019 in the Santa Barbara Basin using ROV Jason during R/V Atlantis cruise AT42-19 (Version 1) [data set], Biological and Chemical Oceanography Data Management Office (BCO-DMO). https://doi.org/10.26008/1912/BCO-DMO.867113.1, 2022b.
Treude, T. and Valentine, D. L.: Microbial activity from sediments collected Fall 2019 in the Santa Barbara Basin using ROV Jason during R/V Atlantis cruise AT42-19 (Version 1) [data set], Biological and Chemical Oceanography Data Management Office (BCO-DMO). https://doi.org/10.26008/1912/BCO-DMO.867221.1, 2022c.
Treude, T. and Valentine, D. L.: Benthic fluxes of solutes measured by in-situ benthic flux chambers along two depth transects in the Santa Barbara Basin during November 219 (Version 1) [data Set], Biological and Chemical Oceanography Data Management Office (BCO-DMO). https://doi.org/10.26008/1912/bco-dmo.896706.1, 2023.
Valentine, D. L., Fisher, G. B., Pizarro, O., Kaiser, C. L., Yoerger, D., Breier, J. A., and Tarn, J.: Autonomous marine robotic technology reveals an expansive benthic bacterial community relevant to regional nitrogen biogeochemistry, Environ. Sci. Technol., 50, 11057–11065, 2016.
Van Cappellen, P. and Ingall, E. D.: Benthic phosphorus regeneration, net primary production, and ocean anoxia: A model of the coupled marine biogeochemical cycles of carbon and phosphorus, Paleoceanography, 9, 677–692, 1994.
Van De Velde, S., Lesven, L., Burdorf, L. D., Hidalgo-Martinez, S., Geelhoed, J. S., Van Rijswijk, P., Gao, Y., and Meysman, F. J.: The impact of electrogenic sulfur oxidation on the biogeochemistry of coastal sediments: A field study, Geochim. Cosmochim. Ac., 194, 211–232, 2016.
van de Velde, S. J., Hylén, A., Kononets, M., Marzocchi, U., Leermakers, M., Choumiline, K., Hall, P. O., and Meysman, F. J.: Elevated sedimentary removal of Fe, Mn, and trace elements following a transient oxygenation event in the Eastern Gotland Basin, central Baltic Sea, Geochim. Cosmochim. Ac., 271, 16–32, 2020.
van de Velde, S. J., Hylén, A., Eriksson, M., James, R. K., Kononets, M. Y., Robertson, E. K., and Hall, P. O.: Exceptionally high respiration rates in the reactive surface layer of sediments underlying oxygen-deficient bottom waters, P. Roy. Soc. A-Math. Phy., 479, 20230189, https://doi.org/10.1098/rspa.2023.0189, 2023.
Wallmann, K., José, Y. S., Hopwood, M. J., Somes, C. J., Dale, A. W., Scholz, F., Achterberg, E. P., and Oschlies, A.: Biogeochemical feedbacks may amplify ongoing and future ocean deoxygenation: a case study from the Peruvian oxygen minimum zone, Biogeochemistry, 159, 45–67, 2022.
Ward, B., Devol, A., Rich, J., Chang, B., Bulow, S., Naik, H., Pratihary, A., and Jayakumar, A.: Denitrification as the dominant nitrogen loss process in the Arabian Sea, Nature, 461, 78–81, 2009.
Zhang, L., Altabet, M. A., Wu, T., and Hadas, O.: Sensitive measurement of NH4 +
Zopfi, J., Kjær, T., Nielsen, L. P., and Jørgensen, B. B.: Ecology of Thioploca spp.: nitrate and sulfur storage in relation to chemical microgradients and influence of Thioploca spp. on the sedimentary nitrogen cycle, Appl. Environ. Microb., 67, 5530–5537, 2001.
Short summary
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.
Declining oxygen (O2) concentrations in coastal oceans can threaten people’s ways of life and...
Altmetrics
Final-revised paper
Preprint