Articles | Volume 18, issue 3
https://doi.org/10.5194/bg-18-775-2021
© Author(s) 2021. 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-18-775-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Technical note
| 
02 Feb 2021
Technical note |
| 02 Feb 2021
| 02 Feb 2021
Technical note: A universal method for measuring the thickness of microscopic calcite crystals, based on bidirectional circular polarization
Aix Marseille Univ, CNRS, IRD, INRAE, Coll. France, CEREGE,
Aix-en-Provence, France
Yves Gally
Aix Marseille Univ, CNRS, IRD, INRAE, Coll. France, CEREGE,
Aix-en-Provence, France
Baptiste Suchéras-Marx
Aix Marseille Univ, CNRS, IRD, INRAE, Coll. France, CEREGE,
Aix-en-Provence, France
Patrick Ferrand
Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel,
Marseille, France
Julien Duboisset
Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel,
Marseille, France
Related authors
Deborah N. Tangunan, Ian R. Hall, Luc Beaufort, Melissa A. Berke, Alexandra Nederbragt, and Paul R. Bown
EGUsphere, https://doi.org/10.5194/egusphere-2025-3557, https://doi.org/10.5194/egusphere-2025-3557, 2025
This preprint is open for discussion and under review for Climate of the Past (CP).
Short summary
Short summary
We examined ocean sediments from the tropical Indian Ocean to study water column structure and carbon cycling during the mid-Piacenzian Warm Period, about 3 million years ago, when atmospheric carbon dioxide levels were similar to today. Our findings reveal persistent upper ocean stratification and niche separation among plankton groups, which limited nutrient mixing and carbon export to the deep ocean. These results highlight how ocean layering can influence climate feedback in a warmer world.
Pauline Cornuault, Luc Beaufort, Heiko Pälike, Torsten Bickert, Karl-Heinz Baumann, and Michal Kucera
EGUsphere, https://doi.org/10.5194/egusphere-2025-198, https://doi.org/10.5194/egusphere-2025-198, 2025
Short summary
Short summary
We present new high-resolution data of the relative contribution of the two main pelagic carbonate producers (coccoliths and foraminifera) to the total pelagic carbonate production from the tropical Atlantic in past warm periods since the Miocene. Our findings suggests that the two groups responded differently to orbital forcing and oceanic changes in tropical ocean, but their proportion changes did not drive the changes in overall pelagic carbonate deposition.
Luc Beaufort and Anta-Clarisse Sarr
Clim. Past, 20, 1283–1301, https://doi.org/10.5194/cp-20-1283-2024, https://doi.org/10.5194/cp-20-1283-2024, 2024
Short summary
Short summary
At present, under low eccentricity, the tropical ocean experiences a limited seasonality. Based on eight climate simulations of sea surface temperature and primary production, we show that, during high-eccentricity times, significant seasons existed in the tropics due to annual changes in the Earth–Sun distance. Those tropical seasons are slowly shifting in the calendar year to be distinct from classical seasons. Their past dynamics should have influenced phenomena like ENSO and monsoons.
Celina Rebeca Valença, Luc Beaufort, Gustaaf Marinus Hallegraeff, and Marius Nils Müller
Biogeosciences, 21, 1601–1611, https://doi.org/10.5194/bg-21-1601-2024, https://doi.org/10.5194/bg-21-1601-2024, 2024
Short summary
Short summary
Coccolithophores contribute to the global carbon cycle and their calcite structures (coccoliths) are used as a palaeoproxy to understand past oceanographic conditions. Here, we compared three frequently used methods to estimate coccolith mass from the model species Emiliania huxleyi and the results allow for a high level of comparability between the methods, facilitating future comparisons and consolidation of mass changes observed from ecophysiological and biogeochemical studies.
Martin Tetard, Laetitia Licari, Ekaterina Ovsepyan, Kazuyo Tachikawa, and Luc Beaufort
Biogeosciences, 18, 2827–2841, https://doi.org/10.5194/bg-18-2827-2021, https://doi.org/10.5194/bg-18-2827-2021, 2021
Short summary
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Oxygen minimum zones are oceanic regions almost devoid of dissolved oxygen and are currently expanding due to global warming. Investigation of their past behaviour will allow better understanding of these areas and better prediction of their future evolution. A new method to estimate past [O2] was developed based on morphometric measurements of benthic foraminifera. This method and two other approaches based on foraminifera assemblages and porosity were calibrated using 45 core tops worldwide.
Martin Tetard, Ross Marchant, Giuseppe Cortese, Yves Gally, Thibault de Garidel-Thoron, and Luc Beaufort
Clim. Past, 16, 2415–2429, https://doi.org/10.5194/cp-16-2415-2020, https://doi.org/10.5194/cp-16-2415-2020, 2020
Short summary
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Radiolarians are marine micro-organisms that produce a siliceous shell that is preserved in the fossil record and can be used to reconstruct past climate variability. However, their study is only possible after a time-consuming manual selection of their shells from the sediment followed by their individual identification. Thus, we develop a new fully automated workflow consisting of microscopic radiolarian image acquisition, image processing and identification using artificial intelligence.
Xinquan Zhou, Stéphanie Duchamp-Alphonse, Masa Kageyama, Franck Bassinot, Luc Beaufort, and Christophe Colin
Clim. Past, 16, 1969–1986, https://doi.org/10.5194/cp-16-1969-2020, https://doi.org/10.5194/cp-16-1969-2020, 2020
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We provide a high-resolution primary productivity (PP) record of the northeastern Bay of Bengal over the last 26 000 years. Combined with climate model outputs, we show that PP over the glacial period is controlled by river input nutrients under low sea level conditions and after the Last Glacial Maximum is controlled by upper seawater salinity stratification related to monsoon precipitation. During the deglaciation the Atlantic meridional overturning circulation is the main forcing factor.
Priscilla Le Mézo, Luc Beaufort, Laurent Bopp, Pascale Braconnot, and Masa Kageyama
Clim. Past, 13, 759–778, https://doi.org/10.5194/cp-13-759-2017, https://doi.org/10.5194/cp-13-759-2017, 2017
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This paper focuses on the relationship between Arabian Sea biological productivity and the Indian summer monsoon in climates of the last 72 kyr. A general circulation model coupled to a biogeochemistry model simulates the changes in productivity and monsoon intensity and pattern. The paradigm stating that a stronger summer monsoon enhances productivity is not always verified in our simulations. This work highlights the importance of considering the monsoon pattern in addition to its intensity.
K. J. S. Meier, L. Beaufort, S. Heussner, and P. Ziveri
Biogeosciences, 11, 2857–2869, https://doi.org/10.5194/bg-11-2857-2014, https://doi.org/10.5194/bg-11-2857-2014, 2014
C. J. O'Brien, J. A. Peloquin, M. Vogt, M. Heinle, N. Gruber, P. Ajani, H. Andruleit, J. Arístegui, L. Beaufort, M. Estrada, D. Karentz, E. Kopczyńska, R. Lee, A. J. Poulton, T. Pritchard, and C. Widdicombe
Earth Syst. Sci. Data, 5, 259–276, https://doi.org/10.5194/essd-5-259-2013, https://doi.org/10.5194/essd-5-259-2013, 2013
Deborah N. Tangunan, Ian R. Hall, Luc Beaufort, Melissa A. Berke, Alexandra Nederbragt, and Paul R. Bown
EGUsphere, https://doi.org/10.5194/egusphere-2025-3557, https://doi.org/10.5194/egusphere-2025-3557, 2025
This preprint is open for discussion and under review for Climate of the Past (CP).
Short summary
Short summary
We examined ocean sediments from the tropical Indian Ocean to study water column structure and carbon cycling during the mid-Piacenzian Warm Period, about 3 million years ago, when atmospheric carbon dioxide levels were similar to today. Our findings reveal persistent upper ocean stratification and niche separation among plankton groups, which limited nutrient mixing and carbon export to the deep ocean. These results highlight how ocean layering can influence climate feedback in a warmer world.
Rajkumar Chowdhury, Redhouane Boudjehem, Baptiste Suchéras-Marx, Maxime Dupraz, Anico Kulow, Julio Cesar da Silva, Jean Louis Hazemann, Marie-Pierre Aubry, Javier Pérez, Alejandro Fernandez-Martinez, and Fabienne Giraud
EGUsphere, https://doi.org/10.5194/egusphere-2025-1840, https://doi.org/10.5194/egusphere-2025-1840, 2025
Short summary
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Nannoconus, a major marine planktonic biocarbonate producer of the Early Cretaceous (150–120 Ma), biomineralized heavy (200–1400 picogram) skeletons (5–20 μm) of interlocking lamellae spanned around a central canal, by an unknown process. With the first-ever application of synchrotron-based ptychographic X-ray computed tomography (PXCT) of nanometric resolution, we reconstructed the 3D skeleton by combining segments of lamellae and inferred its possible biomolecule(s)- “templated” calcification.
Pauline Cornuault, Luc Beaufort, Heiko Pälike, Torsten Bickert, Karl-Heinz Baumann, and Michal Kucera
EGUsphere, https://doi.org/10.5194/egusphere-2025-198, https://doi.org/10.5194/egusphere-2025-198, 2025
Short summary
Short summary
We present new high-resolution data of the relative contribution of the two main pelagic carbonate producers (coccoliths and foraminifera) to the total pelagic carbonate production from the tropical Atlantic in past warm periods since the Miocene. Our findings suggests that the two groups responded differently to orbital forcing and oceanic changes in tropical ocean, but their proportion changes did not drive the changes in overall pelagic carbonate deposition.
Luc Beaufort and Anta-Clarisse Sarr
Clim. Past, 20, 1283–1301, https://doi.org/10.5194/cp-20-1283-2024, https://doi.org/10.5194/cp-20-1283-2024, 2024
Short summary
Short summary
At present, under low eccentricity, the tropical ocean experiences a limited seasonality. Based on eight climate simulations of sea surface temperature and primary production, we show that, during high-eccentricity times, significant seasons existed in the tropics due to annual changes in the Earth–Sun distance. Those tropical seasons are slowly shifting in the calendar year to be distinct from classical seasons. Their past dynamics should have influenced phenomena like ENSO and monsoons.
Celina Rebeca Valença, Luc Beaufort, Gustaaf Marinus Hallegraeff, and Marius Nils Müller
Biogeosciences, 21, 1601–1611, https://doi.org/10.5194/bg-21-1601-2024, https://doi.org/10.5194/bg-21-1601-2024, 2024
Short summary
Short summary
Coccolithophores contribute to the global carbon cycle and their calcite structures (coccoliths) are used as a palaeoproxy to understand past oceanographic conditions. Here, we compared three frequently used methods to estimate coccolith mass from the model species Emiliania huxleyi and the results allow for a high level of comparability between the methods, facilitating future comparisons and consolidation of mass changes observed from ecophysiological and biogeochemical studies.
Martin Tetard, Laetitia Licari, Ekaterina Ovsepyan, Kazuyo Tachikawa, and Luc Beaufort
Biogeosciences, 18, 2827–2841, https://doi.org/10.5194/bg-18-2827-2021, https://doi.org/10.5194/bg-18-2827-2021, 2021
Short summary
Short summary
Oxygen minimum zones are oceanic regions almost devoid of dissolved oxygen and are currently expanding due to global warming. Investigation of their past behaviour will allow better understanding of these areas and better prediction of their future evolution. A new method to estimate past [O2] was developed based on morphometric measurements of benthic foraminifera. This method and two other approaches based on foraminifera assemblages and porosity were calibrated using 45 core tops worldwide.
Martin Tetard, Ross Marchant, Giuseppe Cortese, Yves Gally, Thibault de Garidel-Thoron, and Luc Beaufort
Clim. Past, 16, 2415–2429, https://doi.org/10.5194/cp-16-2415-2020, https://doi.org/10.5194/cp-16-2415-2020, 2020
Short summary
Short summary
Radiolarians are marine micro-organisms that produce a siliceous shell that is preserved in the fossil record and can be used to reconstruct past climate variability. However, their study is only possible after a time-consuming manual selection of their shells from the sediment followed by their individual identification. Thus, we develop a new fully automated workflow consisting of microscopic radiolarian image acquisition, image processing and identification using artificial intelligence.
Xinquan Zhou, Stéphanie Duchamp-Alphonse, Masa Kageyama, Franck Bassinot, Luc Beaufort, and Christophe Colin
Clim. Past, 16, 1969–1986, https://doi.org/10.5194/cp-16-1969-2020, https://doi.org/10.5194/cp-16-1969-2020, 2020
Short summary
Short summary
We provide a high-resolution primary productivity (PP) record of the northeastern Bay of Bengal over the last 26 000 years. Combined with climate model outputs, we show that PP over the glacial period is controlled by river input nutrients under low sea level conditions and after the Last Glacial Maximum is controlled by upper seawater salinity stratification related to monsoon precipitation. During the deglaciation the Atlantic meridional overturning circulation is the main forcing factor.
Baptiste Suchéras-Marx, Emanuela Mattioli, Pascal Allemand, Fabienne Giraud, Bernard Pittet, Julien Plancq, and Gilles Escarguel
Biogeosciences, 16, 2501–2510, https://doi.org/10.5194/bg-16-2501-2019, https://doi.org/10.5194/bg-16-2501-2019, 2019
Short summary
Short summary
Calcareous nannoplankton are photosynthetic plankton producing micrometric calcite platelets having a fossil record covering the past 200 Myr. Based on species richness, platelets size and abundance we observed four evolution phases through time: Jurassic–Early Cretaceous invasion phase of the open ocean, Early Cretaceous–K–Pg extinction specialization phase to the ecological niches, post-K–Pg mass extinction recovery and Eocene–Neogene establishment phase with domination of a few small species.
Priscilla Le Mézo, Luc Beaufort, Laurent Bopp, Pascale Braconnot, and Masa Kageyama
Clim. Past, 13, 759–778, https://doi.org/10.5194/cp-13-759-2017, https://doi.org/10.5194/cp-13-759-2017, 2017
Short summary
Short summary
This paper focuses on the relationship between Arabian Sea biological productivity and the Indian summer monsoon in climates of the last 72 kyr. A general circulation model coupled to a biogeochemistry model simulates the changes in productivity and monsoon intensity and pattern. The paradigm stating that a stronger summer monsoon enhances productivity is not always verified in our simulations. This work highlights the importance of considering the monsoon pattern in addition to its intensity.
Baptiste Suchéras-Marx, Fabienne Giraud, Alex Lena, and Alexandre Simionovici
J. Micropalaeontol., 36, 219–221, https://doi.org/10.1144/jmpaleo2016-013, https://doi.org/10.1144/jmpaleo2016-013, 2016
K. J. S. Meier, L. Beaufort, S. Heussner, and P. Ziveri
Biogeosciences, 11, 2857–2869, https://doi.org/10.5194/bg-11-2857-2014, https://doi.org/10.5194/bg-11-2857-2014, 2014
C. J. O'Brien, J. A. Peloquin, M. Vogt, M. Heinle, N. Gruber, P. Ajani, H. Andruleit, J. Arístegui, L. Beaufort, M. Estrada, D. Karentz, E. Kopczyńska, R. Lee, A. J. Poulton, T. Pritchard, and C. Widdicombe
Earth Syst. Sci. Data, 5, 259–276, https://doi.org/10.5194/essd-5-259-2013, https://doi.org/10.5194/essd-5-259-2013, 2013
Related subject area
Biogeochemistry: Biomineralization
Magnesium (Mg∕Ca, δ26Mg), boron (B∕Ca, δ11B), and calcium (Ca2+) geochemistry of Arctica islandica and Crassostrea virginica extrapallial fluid and shell under ocean acidification
Low sensitivity of a heavily calcified coccolithophore under increasing CO2: the case study of Helicosphaera carteri
The calcitic test growth rate of Spirillina vivipara (Foraminifera)
Impact of seawater sulfate concentration on sulfur concentration and isotopic composition in calcite of two cultured benthic foraminifera
Marked recent declines in boron in Baltic Sea cod otoliths – a bellwether of incipient acidification in a vast hypoxic system?
Ocean acidification enhances primary productivity and nocturnal carbonate dissolution in intertidal rock pools
Biomineralization of amorphous Fe-, Mn- and Si-rich mineral phases by cyanobacteria under oxic and alkaline conditions
Biogenic calcium carbonate as evidence for life
Element ∕ Ca ratios in Nodosariida (Foraminifera) and their potential application for paleoenvironmental reconstructions
Deciphering the origin of dubiofossils from the Pennsylvanian of the Paraná Basin, Brazil
Properties of exopolymeric substances (EPSs) produced during cyanobacterial growth: potential role in whiting events
Inorganic component in oak waterlogged archaeological wood and volcanic lake compartments
Ultradian rhythms in shell composition of photosymbiotic and non-photosymbiotic mollusks
Extracellular enzyme activity in the coastal upwelling system off Peru: a mesocosm experiment
Multi-proxy assessment of brachiopod shell calcite as a potential archive of seawater temperature and oxygen isotope composition
Upper-ocean flux of biogenic calcite produced by the Arctic planktonic foraminifera Neogloboquadrina pachyderma
Do bacterial viruses affect framboid-like mineral formation?
Calcification response of reef corals to seasonal upwelling in the northern Arabian Sea (Masirah Island, Oman)
Growth rate rather than temperature affects the B∕Ca ratio in the calcareous red alga Lithothamnion corallioides
Heavy metal uptake of nearshore benthic foraminifera during multi-metal culturing experiments
A stable ultrastructural pattern despite variable cell size in Lithothamnion corallioides
Decoupling salinity and carbonate chemistry: low calcium ion concentration rather than salinity limits calcification in Baltic Sea mussels
The patterns of elemental concentration (Ca, Na, Sr, Mg, Mn, Ba, Cu, Pb, V, Y, U and Cd) in shells of invertebrates representing different CaCO3 polymorphs: a case study from the brackish Gulf of Gdańsk (the Baltic Sea)
Carbonic anhydrase is involved in calcification by the benthic foraminifer Amphistegina lessonii
Distribution of chlorine and fluorine in benthic foraminifera
Rare earth elements in oyster shells: provenance discrimination and potential vital effects
Determining how biotic and abiotic variables affect the shell condition and parameters of Heliconoides inflatus pteropods from a sediment trap in the Cariaco Basin
Intercomparison of four methods to estimate coral calcification under various environmental conditions
Technical note: The silicon isotopic composition of choanoflagellates: implications for a mechanistic understanding of isotopic fractionation during biosilicification
Insights into architecture, growth dynamics, and biomineralization from pulsed Sr-labelled Katelysia rhytiphora shells (Mollusca, Bivalvia)
Subaqueous speleothems (Hells Bells) formed by the interplay of pelagic redoxcline biogeochemistry and specific hydraulic conditions in the El Zapote sinkhole, Yucatán Peninsula, Mexico
Kinetics of calcite precipitation by ureolytic bacteria under aerobic and anaerobic conditions
Coupled calcium and inorganic carbon uptake suggested by magnesium and sulfur incorporation in foraminiferal calcite
Planktonic foraminiferal spine versus shell carbonate Na incorporation in relation to salinity
Precipitation of calcium carbonate mineral induced by viral lysis of cyanobacteria: evidence from laboratory experiments
Mineral formation induced by cable bacteria performing long-distance electron transport in marine sediments
Variation in brachiopod microstructure and isotope geochemistry under low-pH–ocean acidification conditions
Weaving of biomineralization framework in rotaliid foraminifera: implications for paleoceanographic proxies
Marine and freshwater micropearls: biomineralization producing strontium-rich amorphous calcium carbonate inclusions is widespread in the genus Tetraselmis (Chlorophyta)
Carbon and nitrogen turnover in the Arctic deep sea: in situ benthic community response to diatom and coccolithophorid phytodetritus
Technical note: A refinement of coccolith separation methods: measuring the sinking characteristics of coccoliths
Improving the strength of sandy soils via ureolytic CaCO3 solidification by Sporosarcina ureae
Impact of salinity on element incorporation in two benthic foraminiferal species with contrasting magnesium contents
Calcification in a marginal sea – influence of seawater [Ca2+] and carbonate chemistry on bivalve shell formation
Effect of temperature rise and ocean acidification on growth of calcifying tubeworm shells (Spirorbis spirorbis): an in situ benthocosm approach
Phosphorus limitation and heat stress decrease calcification in Emiliania huxleyi
Anatomical structure overrides temperature controls on magnesium uptake – calcification in the Arctic/subarctic coralline algae Leptophytum laeve and Kvaleya epilaeve (Rhodophyta; Corallinales)
Coral calcifying fluid aragonite saturation states derived from Raman spectroscopy
Impact of trace metal concentrations on coccolithophore growth and morphology: laboratory simulations of Cretaceous stress
Ba incorporation in benthic foraminifera
Blanca Alvarez Caraveo, Maxence Guillermic, Alan Downey-Wall, Louise P. Cameron, Jill N. Sutton, John A. Higgins, Justin B. Ries, Katie Lotterhos, and Robert A. Eagle
Biogeosciences, 22, 2831–2851, https://doi.org/10.5194/bg-22-2831-2025, https://doi.org/10.5194/bg-22-2831-2025, 2025
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We studied the geochemistry of two bivalves: Crassostrea virginica and Arctica islandica. We examined the effects of three ocean acidification conditions (ambient, moderate, and high) on the geochemistry of C. virginica. We show that bivalves have high physiological control over the internal calcifying fluid, presenting a challenge in using elemental proxies for reconstructing seawater parameters.
Stefania Bianco, Manuela Bordiga, Gerald Langer, Patrizia Ziveri, Federica Cerino, Andrea Di Giulio, and Claudia Lupi
Biogeosciences, 22, 1821–1837, https://doi.org/10.5194/bg-22-1821-2025, https://doi.org/10.5194/bg-22-1821-2025, 2025
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This work focuses on the response in culture experiments to increasing CO2 of the coccolithophore species Helicosphaera carteri, a unicellular marine calcifying microalgae. The absence of significant changes in coccolith malformations, along with stable size, shape, and calcification-to-photosynthesis ratio, is indicative of H. carteri low sensitivity to CO2 rise, together with its ability to maintain a stable contribution to the marine rain ratio under future climate changes.
Yukiko Nagai, Katsuyuki Uematsu, Briony Mamo, and Takashi Toyofuku
Biogeosciences, 21, 1675–1684, https://doi.org/10.5194/bg-21-1675-2024, https://doi.org/10.5194/bg-21-1675-2024, 2024
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This research highlights Spirillina vivipara's calcification strategy, highlighting variability in foraminiferal test formation. By examining its rapid growth and high calcification rate, we explain ecological strategies correlating with its broad coastal distribution. These insights amplify our understanding of foraminiferal ecology and underscore their impact on marine carbon cycling and paleoclimate studies, advocating for a species-specific approach in future research.
Caroline Thaler, Guillaume Paris, Marc Dellinger, Delphine Dissard, Sophie Berland, Arul Marie, Amandine Labat, and Annachiara Bartolini
Biogeosciences, 20, 5177–5198, https://doi.org/10.5194/bg-20-5177-2023, https://doi.org/10.5194/bg-20-5177-2023, 2023
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Our study focuses on one of the most used microfossils in paleoenvironmental reconstructions: foraminifera. We set up a novel approach of long-term cultures under variable and controlled conditions. Our results highlight that foraminiferal tests can be used as a unique record of both SO42−/CaCO3 and δ34S seawater variation. This establishes geological formations composed of biogenic carbonates as a potential repository of paleoenvironmental seawater sulfate chemical and geochemical variation.
Karin E. Limburg, Yvette Heimbrand, and Karol Kuliński
Biogeosciences, 20, 4751–4760, https://doi.org/10.5194/bg-20-4751-2023, https://doi.org/10.5194/bg-20-4751-2023, 2023
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We found a 3-to-5-fold decline in boron in Baltic cod otoliths between the late 1990s and 2021. The trend correlates with declines in oxygen and pH but not with increased salinity. Otolith B : Ca correlated with phosphorus in a healthy out-group (Icelandic cod) but not in Baltic cod. The otolith biomarkers Mn : Mg (hypoxia proxy) and B : Ca in cod otoliths suggest a general increase in both hypoxia and acidification within Baltic intermediate and deep waters in the last decade.
Narimane Dorey, Sophie Martin, and Lester Kwiatkowski
Biogeosciences, 20, 4289–4306, https://doi.org/10.5194/bg-20-4289-2023, https://doi.org/10.5194/bg-20-4289-2023, 2023
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Human CO2 emissions are modifying ocean carbonate chemistry, causing ocean acidification and likely already impacting marine ecosystems. Here, we added CO2 to intertidal pools at the start of emersion to investigate the influence of future ocean acidification on net community production (NCP) and calcification (NCC). By day, adding CO2 fertilized the pools (+20 % NCP). By night, pools experienced net community dissolution, a dissolution that was further increased (+40 %) by the CO2 addition.
Karim Benzerara, Agnès Elmaleh, Maria Ciobanu, Alexis De Wever, Paola Bertolino, Miguel Iniesto, Didier Jézéquel, Purificación López-García, Nicolas Menguy, Elodie Muller, Fériel Skouri-Panet, Sufal Swaraj, Rosaluz Tavera, Christophe Thomazo, and David Moreira
Biogeosciences, 20, 4183–4195, https://doi.org/10.5194/bg-20-4183-2023, https://doi.org/10.5194/bg-20-4183-2023, 2023
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Iron and manganese are poorly soluble in oxic and alkaline solutions but much more soluble under anoxic conditions. As a result, authigenic minerals rich in Fe and/or Mn have been viewed as diagnostic of anoxic conditions. However, here we reveal a new case of biomineralization by specific cyanobacteria, forming abundant Fe(III)- and Mn(IV)-rich amorphous phases under oxic conditions in an alkaline lake. This might be an overlooked biotic contribution to the scavenging of Fe from water columns.
Sara Ronca, Francesco Mura, Marco Brandano, Angela Cirigliano, Francesca Benedetti, Alessandro Grottoli, Massimo Reverberi, Daniele Federico Maras, Rodolfo Negri, Ernesto Di Mauro, and Teresa Rinaldi
Biogeosciences, 20, 4135–4145, https://doi.org/10.5194/bg-20-4135-2023, https://doi.org/10.5194/bg-20-4135-2023, 2023
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The history of Earth is a story of the co-evolution of minerals and microbes. We present the evidence that moonmilk precipitation is driven by microorganisms within the rocks and not only on the rock surfaces. Moreover, the moonmilk produced within the rocks contributes to rock formation. The calcite speleothem moonmilk is the only known carbonate speleothem on Earth with undoubted biogenic origin, thus representing a biosignature of life.
Laura Pacho, Lennart de Nooijer, and Gert-Jan Reichart
Biogeosciences, 20, 4043–4056, https://doi.org/10.5194/bg-20-4043-2023, https://doi.org/10.5194/bg-20-4043-2023, 2023
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We analyzed Mg / Ca and other El / Ca (Na / Ca, B / Ca, Sr / Ca and Ba / Ca) in Nodosariata. Their calcite chemistry is markedly different to that of the other calcifying orders of foraminifera. We show a relation between the species average Mg / Ca and its sensitivity to changes in temperature. Differences were reflected in both the Mg incorporation and the sensitivities of Mg / Ca to temperature.
João Pedro Saldanha, Joice Cagliari, Rodrigo Scalise Horodyski, Lucas Del Mouro, and Mírian Liza Alves Forancelli Pacheco
Biogeosciences, 20, 3943–3979, https://doi.org/10.5194/bg-20-3943-2023, https://doi.org/10.5194/bg-20-3943-2023, 2023
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We analyze a complex and branched mineral structure with an obscure origin, considering form, matrix, composition, and context. Comparisons eliminate controlled biominerals. The structure's intricate history suggests microbial influence and alterations, followed by a thermal event. Complex interactions shaped its forms, making origin classification tougher. This study highlights the elaborated nature of dubiofossils, identifying challenges in distinguishing biominerals from abiotic minerals.
Marlisa Martinho de Brito, Irina Bundeleva, Frédéric Marin, Emmanuelle Vennin, Annick Wilmotte, Laurent Plasseraud, and Pieter T. Visscher
Biogeosciences, 20, 3165–3183, https://doi.org/10.5194/bg-20-3165-2023, https://doi.org/10.5194/bg-20-3165-2023, 2023
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Cyanobacterial blooms are associated with whiting events – natural occurrences of fine-grained carbonate precipitation in the water column. The role of organic matter (OM) produced by cyanobacteria in these events has been overlooked in previous research. Our laboratory experiments showed that OM affects the size and quantity of CaCO3 minerals. We propose a model of OM-associated CaCO3 precipitation during picoplankton blooms, which may have been neglected in modern and ancient events.
Giancarlo Sidoti, Federica Antonelli, Giulia Galotta, Maria Cristina Moscatelli, Davor Kržišnik, Vittorio Vinciguerra, Swati Tamantini, Rosita Marabottini, Natalia Macro, and Manuela Romagnoli
Biogeosciences, 20, 3137–3149, https://doi.org/10.5194/bg-20-3137-2023, https://doi.org/10.5194/bg-20-3137-2023, 2023
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The mineral content in archaeological wood pile dwellings and in the surrounding sediments in a volcanic lake was investigated. Calcium was the most abundant element; the second most abundant element was arsenic in sapwood. Sulfur, iron and potassium were also present. The mineral compounds are linked to the volcanic origin of the lake, to bioaccumulation processes induced by bacteria (i.e. sulfate-reducing bacteria) and to biochemical processes.
Niels J. de Winter, Daniel Killam, Lukas Fröhlich, Lennart de Nooijer, Wim Boer, Bernd R. Schöne, Julien Thébault, and Gert-Jan Reichart
Biogeosciences, 20, 3027–3052, https://doi.org/10.5194/bg-20-3027-2023, https://doi.org/10.5194/bg-20-3027-2023, 2023
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Mollusk shells are valuable recorders of climate and environmental changes of the past down to a daily resolution. To explore this potential, we measured changes in the composition of shells of two types of bivalves recorded at the hourly scale: the king scallop Pecten maximus and giant clams (Tridacna) that engaged in photosymbiosis. We find that photosymbiosis produces more day–night fluctuation in shell chemistry but that most of the variation is not periodic, perhaps recording weather.
Kristian Spilling, Jonna Piiparinen, Eric P. Achterberg, Javier Arístegui, Lennart T. Bach, Maria T. Camarena-Gómez, Elisabeth von der Esch, Martin A. Fischer, Markel Gómez-Letona, Nauzet Hernández-Hernández, Judith Meyer, Ruth A. Schmitz, and Ulf Riebesell
Biogeosciences, 20, 1605–1619, https://doi.org/10.5194/bg-20-1605-2023, https://doi.org/10.5194/bg-20-1605-2023, 2023
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We carried out an enclosure experiment using surface water off Peru with different additions of oxygen minimum zone water. In this paper, we report on enzyme activity and provide data on the decomposition of organic matter. We found very high activity with respect to an enzyme breaking down protein, suggesting that this is important for nutrient recycling both at present and in the future ocean.
Thomas Letulle, Danièle Gaspard, Mathieu Daëron, Florent Arnaud-Godet, Arnauld Vinçon-Laugier, Guillaume Suan, and Christophe Lécuyer
Biogeosciences, 20, 1381–1403, https://doi.org/10.5194/bg-20-1381-2023, https://doi.org/10.5194/bg-20-1381-2023, 2023
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This paper studies the chemistry of modern marine shells called brachiopods. We investigate the relationship of the chemistry of these shells with sea temperatures to test and develop tools for estimating sea temperatures in the distant past. Our results confirm that two of the investigated chemical markers could be useful thermometers despite some second-order variability independent of temperature. The other chemical markers investigated, however, should not be used as a thermometer.
Franziska Tell, Lukas Jonkers, Julie Meilland, and Michal Kucera
Biogeosciences, 19, 4903–4927, https://doi.org/10.5194/bg-19-4903-2022, https://doi.org/10.5194/bg-19-4903-2022, 2022
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This study analyses the production of calcite shells formed by one of the main Arctic pelagic calcifiers, the foraminifera N. pachyderma. Using vertically resolved profiles of shell concentration, size and weight, we show that calcification occurs throughout the upper 300 m with an average production flux below the calcification zone of 8 mg CaCO3 m−2 d−1 representing 23 % of the total pelagic biogenic carbonate production. The production flux is attenuated in the twilight zone by dissolution.
Paweł Działak, Marcin D. Syczewski, Kamil Kornaus, Mirosław Słowakiewicz, Łukasz Zych, and Andrzej Borkowski
Biogeosciences, 19, 4533–4550, https://doi.org/10.5194/bg-19-4533-2022, https://doi.org/10.5194/bg-19-4533-2022, 2022
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Bacteriophages comprise one of the factors that may influence mineralization processes. The number of bacteriophages in the environment usually exceeds the number of bacteria by an order of magnitude. One of the more interesting processes is the formation of framboidal pyrite, and it is not entirely clear what processes determine its formation. Our studies indicate that some bacterial viruses may influence the formation of framboid-like or spherical structures.
Philipp M. Spreter, Markus Reuter, Regina Mertz-Kraus, Oliver Taylor, and Thomas C. Brachert
Biogeosciences, 19, 3559–3573, https://doi.org/10.5194/bg-19-3559-2022, https://doi.org/10.5194/bg-19-3559-2022, 2022
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We investigate the calcification rate of reef corals from an upwelling zone, where low seawater pH and high nutrient concentrations represent a recent analogue for the future ocean. Calcification rate of the corals largely relies on extension growth. Variable responses of extension growth to nutrients either compensate or exacerbate negative effects of weak skeletal thickening associated with low seawater pH – a mechanism that is critical for the persistence of coral reefs under global change.
Giulia Piazza, Valentina A. Bracchi, Antonio Langone, Agostino N. Meroni, and Daniela Basso
Biogeosciences, 19, 1047–1065, https://doi.org/10.5194/bg-19-1047-2022, https://doi.org/10.5194/bg-19-1047-2022, 2022
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The coralline alga Lithothamnion corallioides is widely distributed in the Mediterranean Sea and NE Atlantic Ocean, where it constitutes rhodolith beds, which are diversity-rich ecosystems on the seabed. The boron incorporated in the calcified thallus of coralline algae (B/Ca) can be used to trace past changes in seawater carbonate and pH. This paper suggests a non-negligible effect of algal growth rate on B/Ca, recommending caution in adopting this proxy for paleoenvironmental reconstructions.
Sarina Schmidt, Ed C. Hathorne, Joachim Schönfeld, and Dieter Garbe-Schönberg
Biogeosciences, 19, 629–664, https://doi.org/10.5194/bg-19-629-2022, https://doi.org/10.5194/bg-19-629-2022, 2022
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The study addresses the potential of marine shell-forming organisms as proxy carriers for heavy metal contamination in the environment. The aim is to investigate if the incorporation of heavy metals is a direct function of their concentration in seawater. Culturing experiments with a metal mixture were carried out over a wide concentration range. Our results show shell-forming organisms to be natural archives that enable the determination of metals in polluted and pristine environments.
Valentina Alice Bracchi, Giulia Piazza, and Daniela Basso
Biogeosciences, 18, 6061–6076, https://doi.org/10.5194/bg-18-6061-2021, https://doi.org/10.5194/bg-18-6061-2021, 2021
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Ultrastructures of Lithothamnion corallioides, a crustose coralline alga collected from the Atlantic and Mediterranean Sea at different depths, show high-Mg-calcite cell walls formed by crystals with a specific shape and orientation that are unaffected by different environmental conditions of the living sites. This suggests that the biomineralization process is biologically controlled in coralline algae and can have interesting applications in paleontology.
Trystan Sanders, Jörn Thomsen, Jens Daniel Müller, Gregor Rehder, and Frank Melzner
Biogeosciences, 18, 2573–2590, https://doi.org/10.5194/bg-18-2573-2021, https://doi.org/10.5194/bg-18-2573-2021, 2021
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The Baltic Sea is expected to experience a rapid drop in salinity and increases in acidity and warming in the next century. Calcifying mussels dominate Baltic Sea seafloor ecosystems yet are sensitive to changes in seawater chemistry. We combine laboratory experiments and a field study and show that a lack of calcium causes extremely slow growth rates in mussels at low salinities. Subsequently, climate change in the Baltic may have drastic ramifications for Baltic seafloor ecosystems.
Anna Piwoni-Piórewicz, Stanislav Strekopytov, Emma Humphreys-Williams, and Piotr Kukliński
Biogeosciences, 18, 707–728, https://doi.org/10.5194/bg-18-707-2021, https://doi.org/10.5194/bg-18-707-2021, 2021
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Calcifying organisms occur globally in almost every environment, and the process of biomineralization is of great importance in the global carbon cycle and use of skeletons as environmental data archives. The composition of skeletons is very complex. It is determined by the mechanisms of biological control on biomineralization and the response of calcifying organisms to varying environmental drivers. Yet for trace elements, such as Cu, Pb and Cd, an impact of environmental factors is pronounced.
Siham de Goeyse, Alice E. Webb, Gert-Jan Reichart, and Lennart J. de Nooijer
Biogeosciences, 18, 393–401, https://doi.org/10.5194/bg-18-393-2021, https://doi.org/10.5194/bg-18-393-2021, 2021
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Foraminifera are calcifying organisms that play a role in the marine inorganic-carbon cycle and are widely used to reconstruct paleoclimates. However, the fundamental process by which they calcify remains essentially unknown. Here we use inhibitors to show that an enzyme is speeding up the conversion between bicarbonate and CO2. This helps the foraminifera acquire sufficient carbon for calcification and might aid their tolerance to elevated CO2 level.
Anne Roepert, Lubos Polerecky, Esmee Geerken, Gert-Jan Reichart, and Jack J. Middelburg
Biogeosciences, 17, 4727–4743, https://doi.org/10.5194/bg-17-4727-2020, https://doi.org/10.5194/bg-17-4727-2020, 2020
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We investigated, for the first time, the spatial distribution of chlorine and fluorine in the shell walls of four benthic foraminifera species: Ammonia tepida, Amphistegina lessonii, Archaias angulatus, and Sorites marginalis. Cross sections of specimens were imaged using nanoSIMS. The distribution of Cl and F was co-located with organics in the rotaliids and rather homogeneously distributed in miliolids. We suggest that the incorporation is governed by the biomineralization pathway.
Vincent Mouchi, Camille Godbillot, Vianney Forest, Alexey Ulianov, Franck Lartaud, Marc de Rafélis, Laurent Emmanuel, and Eric P. Verrecchia
Biogeosciences, 17, 2205–2217, https://doi.org/10.5194/bg-17-2205-2020, https://doi.org/10.5194/bg-17-2205-2020, 2020
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Rare earth elements (REEs) in coastal seawater are included in bivalve shells during growth, and a regional fingerprint can be defined for provenance and environmental monitoring studies. We present a large dataset of REE abundances from oysters from six locations in France. The cupped oyster can be discriminated from one locality to another, but this is not the case for the flat oyster. Therefore, provenance studies using bivalve shells based on REEs are not adapted for the flat oyster.
Rosie L. Oakes and Jocelyn A. Sessa
Biogeosciences, 17, 1975–1990, https://doi.org/10.5194/bg-17-1975-2020, https://doi.org/10.5194/bg-17-1975-2020, 2020
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Pteropods are a group of tiny swimming snails whose fragile shells put them at risk from ocean acidification. We investigated the factors influencing the thickness of pteropods shells in the Cariaco Basin, off Venezuela, which is unaffected by ocean acidification. We found that pteropods formed thicker shells when nutrient concentrations, an indicator of food availability, were highest, indicating that food may be an important factor in mitigating the effects of ocean acidification on pteropods.
Miguel Gómez Batista, Marc Metian, François Oberhänsli, Simon Pouil, Peter W. Swarzenski, Eric Tambutté, Jean-Pierre Gattuso, Carlos M. Alonso Hernández, and Frédéric Gazeau
Biogeosciences, 17, 887–899, https://doi.org/10.5194/bg-17-887-2020, https://doi.org/10.5194/bg-17-887-2020, 2020
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In this paper, we assessed four methods (total alkalinity anomaly, calcium anomaly, 45Ca incorporation, and 13C incorporation) to determine coral calcification of a reef-building coral. Under all conditions (light vs. dark incubations and ambient vs. lowered pH levels), calcification rates estimated using the alkalinity and calcium anomaly techniques as well as 45Ca incorporation were highly correlated, while significantly different results were obtained with the 13C incorporation technique.
Alan Marron, Lucie Cassarino, Jade Hatton, Paul Curnow, and Katharine R. Hendry
Biogeosciences, 16, 4805–4813, https://doi.org/10.5194/bg-16-4805-2019, https://doi.org/10.5194/bg-16-4805-2019, 2019
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Isotopic signatures of silica fossils can be used as archives of past oceanic silicon cycling, which is linked to marine carbon uptake. However, the biochemistry that lies behind such chemical fingerprints remains poorly understood. We present the first measurements of silicon isotopes in a group of protists closely related to animals, choanoflagellates. Our results highlight a taxonomic basis to silica isotope signatures, possibly via a shared transport pathway in choanoflagellates and animals.
Laura M. Otter, Oluwatoosin B. A. Agbaje, Matt R. Kilburn, Christoph Lenz, Hadrien Henry, Patrick Trimby, Peter Hoppe, and Dorrit E. Jacob
Biogeosciences, 16, 3439–3455, https://doi.org/10.5194/bg-16-3439-2019, https://doi.org/10.5194/bg-16-3439-2019, 2019
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This study uses strontium as a trace elemental marker in combination with high-resolution nano-analytical techniques to label the growth fronts of bivalves in controlled aquaculture conditions. The growing shells incorporate the labels and are used as
snapshotsvisualizing the growth processes across different shell architectures. These observations are combined with structural investigations across length scales and altogether allow for a detailed understanding of this shell.
Simon Michael Ritter, Margot Isenbeck-Schröter, Christian Scholz, Frank Keppler, Johannes Gescher, Lukas Klose, Nils Schorndorf, Jerónimo Avilés Olguín, Arturo González-González, and Wolfgang Stinnesbeck
Biogeosciences, 16, 2285–2305, https://doi.org/10.5194/bg-16-2285-2019, https://doi.org/10.5194/bg-16-2285-2019, 2019
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Unique and spectacular under water speleothems termed as Hells Bells were recently reported from sinkholes (cenotes) of the Yucatán Peninsula, Mexico. However, the mystery of their formation remained unresolved. Here, we present detailed geochemical analyses and delineate that the growth of Hells Bells results from a combination of biogeochemical processes and variable hydraulic conditions within the cenote.
Andrew C. Mitchell, Erika J. Espinosa-Ortiz, Stacy L. Parks, Adrienne J. Phillips, Alfred B. Cunningham, and Robin Gerlach
Biogeosciences, 16, 2147–2161, https://doi.org/10.5194/bg-16-2147-2019, https://doi.org/10.5194/bg-16-2147-2019, 2019
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Microbially induced carbonate mineral precipitation (MICP) is a natural process that is also being investigated for subsurface engineering applications including radionuclide immobilization and microfracture plugging. We demonstrate that rates of MICP from microbial urea hydrolysis (ureolysis) vary with different bacterial strains, but rates are similar in both oxygenated and oxygen-free conditions. Ureolysis MICP is therefore a viable biotechnology in the predominately oxygen-free subsurface.
Inge van Dijk, Christine Barras, Lennart Jan de Nooijer, Aurélia Mouret, Esmee Geerken, Shai Oron, and Gert-Jan Reichart
Biogeosciences, 16, 2115–2130, https://doi.org/10.5194/bg-16-2115-2019, https://doi.org/10.5194/bg-16-2115-2019, 2019
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Systematics in the incorporation of different elements in shells of marine organisms can be used to test calcification models and thus processes involved in precipitation of calcium carbonates. On different scales, we observe a covariation of sulfur and magnesium incorporation in shells of foraminifera, which provides insights into the mechanics behind shell formation. The observed patterns imply that all species of foraminifera actively take up calcium and carbon in a coupled process.
Eveline M. Mezger, Lennart J. de Nooijer, Jacqueline Bertlich, Jelle Bijma, Dirk Nürnberg, and Gert-Jan Reichart
Biogeosciences, 16, 1147–1165, https://doi.org/10.5194/bg-16-1147-2019, https://doi.org/10.5194/bg-16-1147-2019, 2019
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Seawater salinity is an important factor when trying to reconstruct past ocean conditions. Foraminifera, small organisms living in the sea, produce shells that incorporate more Na at higher salinities. The accuracy of reconstructions depends on the fundamental understanding involved in the incorporation and preservation of the original Na of the shell. In this study, we unravel the Na composition of different components of the shell and describe the relative contribution of these components.
Hengchao Xu, Xiaotong Peng, Shijie Bai, Kaiwen Ta, Shouye Yang, Shuangquan Liu, Ho Bin Jang, and Zixiao Guo
Biogeosciences, 16, 949–960, https://doi.org/10.5194/bg-16-949-2019, https://doi.org/10.5194/bg-16-949-2019, 2019
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Viruses have been acknowledged as important components of the marine system for the past 2 decades, but understanding of their role in the functioning of the geochemical cycle remains poor. Results show viral lysis of cyanobacteria can influence the carbonate equilibrium system remarkably and promotes the formation and precipitation of carbonate minerals. Amorphous calcium carbonate (ACC) and aragonite are evident in the lysate, implying that different precipitation processes have occurred.
Nicole M. J. Geerlings, Eva-Maria Zetsche, Silvia Hidalgo-Martinez, Jack J. Middelburg, and Filip J. R. Meysman
Biogeosciences, 16, 811–829, https://doi.org/10.5194/bg-16-811-2019, https://doi.org/10.5194/bg-16-811-2019, 2019
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Multicellular cable bacteria form long filaments that can reach lengths of several centimeters. They affect the chemistry and mineralogy of their surroundings and vice versa. How the surroundings affect the cable bacteria is investigated. They show three different types of biomineral formation: (1) a polymer containing phosphorus in their cells, (2) a sheath of clay surrounding the surface of the filament and (3) the encrustation of a filament via a solid phase containing iron and phosphorus.
Facheng Ye, Hana Jurikova, Lucia Angiolini, Uwe Brand, Gaia Crippa, Daniela Henkel, Jürgen Laudien, Claas Hiebenthal, and Danijela Šmajgl
Biogeosciences, 16, 617–642, https://doi.org/10.5194/bg-16-617-2019, https://doi.org/10.5194/bg-16-617-2019, 2019
Yukiko Nagai, Katsuyuki Uematsu, Chong Chen, Ryoji Wani, Jarosław Tyszka, and Takashi Toyofuku
Biogeosciences, 15, 6773–6789, https://doi.org/10.5194/bg-15-6773-2018, https://doi.org/10.5194/bg-15-6773-2018, 2018
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We interpret detailed SEM and time-lapse observations of the calcification process in living foraminifera, which we reveal to be directly linked to the construction mechanism of organic membranes where the calcium carbonate precipitation takes place. We show that these membranes are a highly perforated outline is first woven by skeletal pseudopodia and then later overlaid by a layer of membranous pseudopodia to close the gaps. The chemical composition is related to these structures.
Agathe Martignier, Montserrat Filella, Kilian Pollok, Michael Melkonian, Michael Bensimon, François Barja, Falko Langenhorst, Jean-Michel Jaquet, and Daniel Ariztegui
Biogeosciences, 15, 6591–6605, https://doi.org/10.5194/bg-15-6591-2018, https://doi.org/10.5194/bg-15-6591-2018, 2018
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The unicellular microalga Tetraselmis cordiformis (Chlorophyta) was recently discovered to form intracellular mineral inclusions, called micropearls, which had been previously overlooked. The present study shows that 10 Tetraselmis species out of the 12 tested share this biomineralization capacity, producing amorphous calcium carbonate inclusions often enriched in Sr. This novel biomineralization process can take place in marine, brackish or freshwater and is therefore a widespread phenomenon.
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
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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.
Hongrui Zhang, Heather Stoll, Clara Bolton, Xiaobo Jin, and Chuanlian Liu
Biogeosciences, 15, 4759–4775, https://doi.org/10.5194/bg-15-4759-2018, https://doi.org/10.5194/bg-15-4759-2018, 2018
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The sinking speeds of coccoliths are relevant for laboratory methods to separate coccoliths for geochemical analysis. However, in the absence of estimates of coccolith settling velocity, previous implementations have depended mainly on time-consuming method development by trial and error. In this study, the sinking velocities of cocooliths were carefully measured for the first time. We also provide an estimation of coccolith sinking velocity by shape, which will make coccolith separation easier.
Justin Michael Whitaker, Sai Vanapalli, and Danielle Fortin
Biogeosciences, 15, 4367–4380, https://doi.org/10.5194/bg-15-4367-2018, https://doi.org/10.5194/bg-15-4367-2018, 2018
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Materials, like soils or cements, can require repair. This study used a new bacterium (Sporosarcina ureae) in a repair method called "microbially induced carbonate precipitation" (MICP). In three trials, benefits were shown: S. ureae could make a model sandy soil much stronger by MICP, in fact better than a lot of other bacteria. However, MICP-treated samples got weaker in three trials of acid rain. In conclusion, S. ureae in MICP repair shows promise when used in appropriate climates.
Esmee Geerken, Lennart Jan de Nooijer, Inge van Dijk, and Gert-Jan Reichart
Biogeosciences, 15, 2205–2218, https://doi.org/10.5194/bg-15-2205-2018, https://doi.org/10.5194/bg-15-2205-2018, 2018
Jörn Thomsen, Kirti Ramesh, Trystan Sanders, Markus Bleich, and Frank Melzner
Biogeosciences, 15, 1469–1482, https://doi.org/10.5194/bg-15-1469-2018, https://doi.org/10.5194/bg-15-1469-2018, 2018
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The distribution of mussel in estuaries is limited but the mechanisms are not well understood. We document for the first time that reduced Ca2+ concentration in the low saline, brackish Baltic Sea affects the ability of mussel larvae to calcify the first larval shell. As complete formation of the shell is a prerequisite for successful development, impaired calcification during this sensitive life stage can have detrimental effects on the species' ability to colonize habitats.
Sha Ni, Isabelle Taubner, Florian Böhm, Vera Winde, and Michael E. Böttcher
Biogeosciences, 15, 1425–1445, https://doi.org/10.5194/bg-15-1425-2018, https://doi.org/10.5194/bg-15-1425-2018, 2018
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Spirorbis tube worms are common epibionts on brown algae in the Baltic Sea. We made experiments with Spirorbis in the
Kiel Outdoor Benthocosmsat CO2 and temperature conditions predicted for the year 2100. The worms were able to grow tubes even at CO2 levels favouring shell dissolution but did not survive at mean temperatures over 24° C. This indicates that Spirorbis worms will suffer from future excessive ocean warming and from ocean acidification fostering corrosion of their protective tubes.
Andrea C. Gerecht, Luka Šupraha, Gerald Langer, and Jorijntje Henderiks
Biogeosciences, 15, 833–845, https://doi.org/10.5194/bg-15-833-2018, https://doi.org/10.5194/bg-15-833-2018, 2018
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Calcifying phytoplankton play an import role in long-term CO2 removal from the atmosphere. We therefore studied the ability of a representative species to continue sequestrating CO2 under future climate conditions. We show that CO2 sequestration is negatively affected by both an increase in temperature and the resulting decrease in nutrient availability. This will impact the biogeochemical cycle of carbon and may have a positive feedback on rising CO2 levels.
Merinda C. Nash and Walter Adey
Biogeosciences, 15, 781–795, https://doi.org/10.5194/bg-15-781-2018, https://doi.org/10.5194/bg-15-781-2018, 2018
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Past seawater temperatures can be reconstructed using magnesium / calcium ratios of biogenic carbonates. As temperature increases, so does magnesium. Here we show that for these Arctic/subarctic coralline algae, anatomy is the first control on Mg / Ca, not temperature. When using coralline algae for temperature reconstruction, it is first necessary to check for anatomical influences on Mg / Ca.
Thomas M. DeCarlo, Juan P. D'Olivo, Taryn Foster, Michael Holcomb, Thomas Becker, and Malcolm T. McCulloch
Biogeosciences, 14, 5253–5269, https://doi.org/10.5194/bg-14-5253-2017, https://doi.org/10.5194/bg-14-5253-2017, 2017
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We present a new technique to quantify the chemical conditions under which corals build their skeletons by analysing them with lasers at a very fine resolution, down to 1/100th the width of a human hair. Our first applications to laboratory-cultured and wild corals demonstrates the complex interplay among seawater conditions (temperature and acidity), calcifying fluid chemistry, and bulk skeleton accretion, which will define the sensitivity of coral calcification to 21st century climate change.
Giulia Faucher, Linn Hoffmann, Lennart T. Bach, Cinzia Bottini, Elisabetta Erba, and Ulf Riebesell
Biogeosciences, 14, 3603–3613, https://doi.org/10.5194/bg-14-3603-2017, https://doi.org/10.5194/bg-14-3603-2017, 2017
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The main goal of this study was to understand if, similarly to the fossil record, high quantities of toxic metals induce coccolith dwarfism in coccolithophore species. We investigated, for the first time, the effects of trace metals on coccolithophore species other than E. huxleyi and on coccolith morphology and size. Our data show a species-specific sensitivity to trace metal concentration, allowing the recognition of the most-, intermediate- and least-tolerant taxa to trace metal enrichments.
Lennart J. de Nooijer, Anieke Brombacher, Antje Mewes, Gerald Langer, Gernot Nehrke, Jelle Bijma, and Gert-Jan Reichart
Biogeosciences, 14, 3387–3400, https://doi.org/10.5194/bg-14-3387-2017, https://doi.org/10.5194/bg-14-3387-2017, 2017
Cited articles
Beaufort, L.: Weight estimates of coccoliths using the optical properties
(birefringence) of calcite, Micropaleontology, 51, 289–298, 2005.
Beaufort, L. and Heussner, S.: Coccolithophorids on the continental slope
of the Bay of Biscay, I. Production, transport and contribution to mass
fluxes, Deep Sea Res. Pt. II, 46, 2147–2174, 1999.
Beaufort, L., Probert, I., and Buchet, N.: Effects of acidification and
primary production on coccolith weight: implications for carbonate transfer
from the surface to the deep ocean, Geochem. Geophys. Geosys., 8, 8, https://doi.org/10.1029/2006GC001493 2007.
Beaufort, L., Probert, I., de Garidel-Thoron, T., Bendif, E. M., Ruiz-Pino,
D., Metzl, N., Goyet, C., Buchet, N., Coupel, P., Grelaud, M., Rost, B.,
Rickaby, R. E. M., and de Vargas, C.: Sensitivity of coccolithophores to
carbonate chemistry and ocean acidification, Nature, 476, 80–84,
https://doi.org/10.1038/nature10295, 2011.
Beaufort, L., Barbarin, N., and Gally, Y.: Optical measurements to determine
the thickness of calcite crystals and the mass of thin carbonate particles
such as coccoliths, Nat. Protoc., 9, 633–642, https://doi.org/10.1038/nprot.2014.028,
2014.
Beuvier, T., Probert, I., Beaufort, L., Suchéras-Marx, B., Chushkin, Y.,
Zontone, F., and Gibaud, A.: X-ray nanotomography of coccolithophores
reveals that coccolith mass and segment number correlate with grid size,
Nature Commun., 10, 751, https://doi.org/10.1038/s41467-019-08635-x, 2019.
Bollmann, J.: Technical Note: Weight approximation of coccoliths using a circular polarizer and interference colour derived retardation estimates – (The CPR Method), Biogeosciences, 11, 1899–1910, https://doi.org/10.5194/bg-11-1899-2014, 2014.
Cubillos, J. C., Henderiks, J., Beaufort, L., Howard, W. R., and
Hallegraeff, G. M.: Reconstructing calcification in ancient
coccolithophores: Individual coccolith weight and morphology of Coccolithus
pelagicus (sensu lato), Mar. Micropaleontol., 92–93, 29–39,
https://doi.org/10.1016/j.marmicro.2012.04.005, 2012.
Fuertes, M. A., Flores, J. A., and Sierro, F. J.: The use of circularly
polarized light for biometry, identification and estimation of mass of
coccoliths, Mar. Micropaleontol., 113, 44–55,
https://doi.org/10.1016/j.marmicro.2014.08.007, 2014.
Giraudeau, J. and Beaufort, L.: Coccolithophores From Extant Population to
Fossil Assemblages, in: Developments in Marine Geology, Proxies in late
Cenozoic Paleoceanography, edited by: Hilaire-Marcel, C. and de Vernal, A.,
Elsevier, Amsterdam, 409–439, 2007.
González-Lemos, S., Guitián, J., Fuertes, M.-Á., Flores, J.-A., and Stoll, H. M.: Technical note: An empirical method for absolute calibration of coccolith thickness, Biogeosciences, 15, 1079–1091, https://doi.org/10.5194/bg-15-1079-2018, 2018.
Hassenkam, T., Johnsson, A., Bechgaard, K., and Stipp, S. L. S.: Tracking
single coccolith dissolution with picogram resolution and implications for
CO2 sequestration and ocean acidification, P. Natl. Acad. Sci. USA, 108, 8571–8576, https://doi.org/10.1073/pnas.1009447108, 2011.
Holligan, P. M., Fernandez, E., Aiken, J., Balch, W. M., Boyd, P., Burkill,
P. H., Finch, M., Groom, S. B., Malin, G., Muller, K., Purdie, D. A.,
Robinson, C., Trees, C. C., Turner, S. M., and van der Wal, P.: A
biogeochemical study of the coccolithophore, Emiliania huxleyi, in the North
Atlantic, Glob. Biogeochem. Cy., 7, 879–900, 1993.
Höning, D.: The impact of life on climate stabilisation over different
timescales, Geochem., Geophys., Geosys., 21, e2020GC009105, https://doi.org/10.1029/2020GC009105, 2020.
Jones, R. C.: A new calculus for the treatment of optical systems, I.
Description and Discussion of the Calculus, J. Opt. Soc. Am., 31, 488–493, https://doi.org/10.1364/JOSA.31.000488, 1941.
Köhler, A.: New method of illumination for photomicrographical purposes,
J. Roy. Microscopic. Soc., 14, 261–262, 1894.
Milliman, J. D. and Droxler, A. W.: Neritic and pelagic carbonate
sedimentation in the marine environment: ignorance is not bliss, Geol.
Rundsch., 85, 496–504, 1996.
Okada, H. and Honjo, S.: The distribution of oceanic coccolithophorids in
the Pacific, Deep Sea Res., 20, 355–374, 1973.
Ridgwell, A. and Zeebe, R. E.: The role of the global carbonate cycle in
the regulation and evolution of the Earth system, Earth Planet.
Sc. Lett., 234, 299–315, https://doi.org/10.1016/j.epsl.2005.03.006, 2005.
Suchéras-Marx, B. and Henderiks, J.: Downsizing the pelagic carbonate
factory: Impacts of calcareous nannoplankton evolution on carbonate burial
over the past 17 million years, Glob. Planet. Change, 123, 97–109,
https://doi.org/10.1016/j.gloplacha.2014.10.015, 2014.
Young, J., Didymus, J. M., Bown, P. R., Prins, B., and Mann, S.: Crystal
assembly and phylogenetic evolution in heterococcoliths, Nature, 356,
516–518, 1992.
Zeebe, R. E. and Westbroek, P.: A simple model for the CaCO3 saturation
state of the ocean: The “Strangelove,” the “Neritan,” and the “Cretan”
Ocean, Geochem., Geophys., Geosys., 4, 1104, https://doi.org/10.1029/2003GC000538, 2003.
Short summary
The coccoliths are major contributors to the particulate inorganic carbon in the ocean. They are extremely difficult to weigh because they are too small to be manipulated. We propose a universal method to measure thickness and weight of fine calcite using polarizing microscopy that does not require fine-tuning of the light or a calibration process. This method named "bidirectional circular polarization" uses two images taken with two directions of a circular polarizer.
The coccoliths are major contributors to the particulate inorganic carbon in the ocean. They are...
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