Articles | Volume 42, issue 1
https://doi.org/10.5194/jm-42-33-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/jm-42-33-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Reply to Fordham and Welter-Schultes's comment on “Taxonomic review of living planktonic foraminifera” by Brummer and Kučera (2022)
MARUM Center for Marine Environmental Sciences, University of Bremen,
Leobener Straße 8, 28359 Bremen, Germany
Geert-Jan A. Brummer
Department of Ocean
Systems, Royal Netherlands Institute for Sea Research (NIOZ), Den Burg, the Netherlands
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The boron isotopic composition (δ11B) of foraminifera shells is an established proxy for the reconstruction of ocean pH. Applications to the Arctic oceans are however limited as robust calibrations in these regions are lacking. Here, we present a new calibration linking δ11B measured in two high-latitude foraminifera species to seawater pH. We show that the δ11B of the species analysed is well correlated with seawater pH and that this calibration can be applied to the paleorecord.
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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.
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Drivers for dinocyst assemblage compositions differ regionally and through time. Shifts in the assemblages can sometimes only be interpreted robustly by locally and sometimes globally calibrated transfer functions, questioning the reliability of environmental reconstructions. We suggest the necessity of a thorough evaluation of transfer function performance and significance for downcore applications to disclose the drivers for present and fossil dinocyst assemblages in a studied core location.
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We generated high-resolution records of carbonate accumulation rate from the Miocene to the Quaternary in the tropical Atlantic Ocean to characterize the variability in pelagic carbonate production during warm climates. It follows orbital cycles, responding to local changes in tropical conditions, as well as to long-term shifts in climate and ocean chemistry. These changes were sufficiently large to play a role in the carbon cycle and global climate evolution.
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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.
Geert-Jan A. Brummer and Michal Kučera
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To aid researchers working with living planktonic foraminifera, we provide a comprehensive review of names that we consider appropriate for extant species. We discuss the reasons for the decisions we made and provide a list of species and genus-level names as well as other names that have been used in the past but are considered inappropriate for living taxa, stating the reasons.
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The variability in the geochemistry among individual foraminifera is used to reconstruct seasonal to interannual climate variability. This method requires that each foraminifera shell accurately records environmental conditions, which we test here using a sediment trap time series. Even in the absence of environmental variability, planktonic foraminifera display variability in their stable isotope ratios that needs to be considered in the interpretation of individual foraminifera data.
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Planktonic foraminifera population dynamics has long been assumed to be controlled by synchronous reproduction and ontogenetic vertical migration (OVM). Due to contradictory observations, this concept became controversial. We here test it in the Atlantic ocean for four species of foraminifera representing the main clades. Our observations support the existence of synchronised reproduction and OVM but show that more than half of the population does not follow the canonical trajectory.
Markus Raitzsch, Jelle Bijma, Torsten Bickert, Michael Schulz, Ann Holbourn, and Michal Kučera
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At approximately 14 Ma, the East Antarctic Ice Sheet expanded to almost its current extent, but the role of CO2 in this major climate transition is not entirely known. We show that atmospheric CO2 might have varied on 400 kyr cycles linked to the eccentricity of the Earth’s orbit. The resulting change in weathering and ocean carbon cycle affected atmospheric CO2 in a way that CO2 rose after Antarctica glaciated, helping to stabilize the climate system on its way to the “ice-house” world.
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The boron isotopic composition (δ11B) of foraminifera shells is an established proxy for the reconstruction of ocean pH. Applications to the Arctic oceans are however limited as robust calibrations in these regions are lacking. Here, we present a new calibration linking δ11B measured in two high-latitude foraminifera species to seawater pH. We show that the δ11B of the species analysed is well correlated with seawater pH and that this calibration can be applied to the paleorecord.
Lukas Jonkers, Tonke Strack, Montserrat Alonso-Garcia, Simon D'haenens, Robert Huber, Michal Kucera, Iván Hernández-Almeida, Chloe L. C. Jones, Brett Metcalfe, Rajeev Saraswat, Lóránd Silye, Sanjay K. Verma, Muhamad Naim Abd Malek, Gerald Auer, Cátia F. Barbosa, Maria A. Barcena, Karl-Heinz Baumann, Flavia Boscolo-Galazzo, Joeven Austine S. Calvelo, Lucilla Capotondi, Martina Caratelli, Jorge Cardich, Humberto Carvajal-Chitty, Markéta Chroustová, Helen K. Coxall, Renata M. de Mello, Anne de Vernal, Paula Diz, Kirsty M. Edgar, Helena L. Filipsson, Ángela Fraguas, Heather L. Furlong, Giacomo Galli, Natalia L. García Chapori, Robyn Granger, Jeroen Groeneveld, Adil Imam, Rebecca Jackson, David Lazarus, Julie Meilland, Marína Molčan Matejová, Raphael Morard, Caterina Morigi, Sven N. Nielsen, Diana Ochoa, Maria Rose Petrizzo, Andrés S. Rigual-Hernández, Marina C. Rillo, Matthew L. Staitis, Gamze Tanık, Raúl Tapia, Nishant Vats, Bridget S. Wade, and Anna E. Weinmann
J. Micropalaeontol., 44, 145–168, https://doi.org/10.5194/jm-44-145-2025, https://doi.org/10.5194/jm-44-145-2025, 2025
Short summary
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Our study provides guidelines improving the reuse of marine microfossil assemblage data, which are valuable for understanding past ecosystems and environmental change. Based on a survey of 113 researchers, we identified key data attributes required for effective reuse. Analysis of a selection of datasets available online reveals a gap between the attributes scientists consider essential and the data currently available, highlighting the need for clearer data documentation and sharing practices.
Pauline Cornuault, Luc Beaufort, Heiko Pälike, Torsten Bickert, Karl-Heinz Baumann, and Michal Kucera
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Short summary
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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.
Miriam Pfeiffer, Hideko Takayanagi, Lars Reuning, Takaaki K. Watanabe, Saori Ito, Dieter Garbe-Schönberg, Tsuyoshi Watanabe, Chung-Che Wu, Chuan-Chou Shen, Jens Zinke, Geert-Jan A. Brummer, and Sri Yudawati Cahyarini
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A coral reconstruction of past climate shows changes in the seasonal cycle of sea surface temperature in the south-eastern tropical Indian Ocean. An enhanced seasonal cycle suggests that the tropical rainfall belt shifted northwards between 1856–1918. We explain this with greater warming in the north-eastern Indian Ocean relative to the south-east, which strengthens surface winds and coastal upwelling in the eastern Indian Ocean, leading to greater cooling south of the Equator.
Sabrina Hohmann, Michal Kucera, and Anne de Vernal
Clim. Past, 19, 2027–2051, https://doi.org/10.5194/cp-19-2027-2023, https://doi.org/10.5194/cp-19-2027-2023, 2023
Short summary
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Drivers for dinocyst assemblage compositions differ regionally and through time. Shifts in the assemblages can sometimes only be interpreted robustly by locally and sometimes globally calibrated transfer functions, questioning the reliability of environmental reconstructions. We suggest the necessity of a thorough evaluation of transfer function performance and significance for downcore applications to disclose the drivers for present and fossil dinocyst assemblages in a studied core location.
Pauline Cornuault, Thomas Westerhold, Heiko Pälike, Torsten Bickert, Karl-Heinz Baumann, and Michal Kucera
Biogeosciences, 20, 597–618, https://doi.org/10.5194/bg-20-597-2023, https://doi.org/10.5194/bg-20-597-2023, 2023
Short summary
Short summary
We generated high-resolution records of carbonate accumulation rate from the Miocene to the Quaternary in the tropical Atlantic Ocean to characterize the variability in pelagic carbonate production during warm climates. It follows orbital cycles, responding to local changes in tropical conditions, as well as to long-term shifts in climate and ocean chemistry. These changes were sufficiently large to play a role in the carbon cycle and global climate evolution.
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
Short summary
Short summary
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.
Geert-Jan A. Brummer and Michal Kučera
J. Micropalaeontol., 41, 29–74, https://doi.org/10.5194/jm-41-29-2022, https://doi.org/10.5194/jm-41-29-2022, 2022
Short summary
Short summary
To aid researchers working with living planktonic foraminifera, we provide a comprehensive review of names that we consider appropriate for extant species. We discuss the reasons for the decisions we made and provide a list of species and genus-level names as well as other names that have been used in the past but are considered inappropriate for living taxa, stating the reasons.
Lukas Jonkers, Geert-Jan A. Brummer, Julie Meilland, Jeroen Groeneveld, and Michal Kucera
Clim. Past, 18, 89–101, https://doi.org/10.5194/cp-18-89-2022, https://doi.org/10.5194/cp-18-89-2022, 2022
Short summary
Short summary
The variability in the geochemistry among individual foraminifera is used to reconstruct seasonal to interannual climate variability. This method requires that each foraminifera shell accurately records environmental conditions, which we test here using a sediment trap time series. Even in the absence of environmental variability, planktonic foraminifera display variability in their stable isotope ratios that needs to be considered in the interpretation of individual foraminifera data.
Lukas Jonkers, Oliver Bothe, and Michal Kucera
Clim. Past, 17, 2577–2581, https://doi.org/10.5194/cp-17-2577-2021, https://doi.org/10.5194/cp-17-2577-2021, 2021
Julie Meilland, Michael Siccha, Maike Kaffenberger, Jelle Bijma, and Michal Kucera
Biogeosciences, 18, 5789–5809, https://doi.org/10.5194/bg-18-5789-2021, https://doi.org/10.5194/bg-18-5789-2021, 2021
Short summary
Short summary
Planktonic foraminifera population dynamics has long been assumed to be controlled by synchronous reproduction and ontogenetic vertical migration (OVM). Due to contradictory observations, this concept became controversial. We here test it in the Atlantic ocean for four species of foraminifera representing the main clades. Our observations support the existence of synchronised reproduction and OVM but show that more than half of the population does not follow the canonical trajectory.
Markus Raitzsch, Jelle Bijma, Torsten Bickert, Michael Schulz, Ann Holbourn, and Michal Kučera
Clim. Past, 17, 703–719, https://doi.org/10.5194/cp-17-703-2021, https://doi.org/10.5194/cp-17-703-2021, 2021
Short summary
Short summary
At approximately 14 Ma, the East Antarctic Ice Sheet expanded to almost its current extent, but the role of CO2 in this major climate transition is not entirely known. We show that atmospheric CO2 might have varied on 400 kyr cycles linked to the eccentricity of the Earth’s orbit. The resulting change in weathering and ocean carbon cycle affected atmospheric CO2 in a way that CO2 rose after Antarctica glaciated, helping to stabilize the climate system on its way to the “ice-house” world.
Maike Leupold, Miriam Pfeiffer, Takaaki K. Watanabe, Lars Reuning, Dieter Garbe-Schönberg, Chuan-Chou Shen, and Geert-Jan A. Brummer
Clim. Past, 17, 151–170, https://doi.org/10.5194/cp-17-151-2021, https://doi.org/10.5194/cp-17-151-2021, 2021
Catarina Cavaleiro, Antje H. L. Voelker, Heather Stoll, Karl-Heinz Baumann, and Michal Kucera
Clim. Past, 16, 2017–2037, https://doi.org/10.5194/cp-16-2017-2020, https://doi.org/10.5194/cp-16-2017-2020, 2020
Cited articles
Brummer, G.-J. A. and Kučera, M.: Taxonomic review of living planktonic foraminifera, J. Micropalaeontol., 41, 29–74, https://doi.org/10.5194/jm-41-29-2022, 2022.
Fordham, B. G.: Miocene–Pleistocene planktic foraminifers from D. S. D. P.
Sites 208 and 77, and phylogeny and classification of Cenozoic species,
Evolutionary Monographs, 6, 1–200, 1986.
ICZN (International Commission on Zoological Nomenclature): International Code of
Zoological Nomenclature, Fourth edition, International Trust for Zoological
Nomenclature, London, I–XXIX, 1–306, ISBN 0 85301 006 4, 1999.
Loeblich Jr., A. R. and Tappan, H.: Foraminiferal genera and their
classification, Van Nostrand Reinhold Company, New York, 1–970, https://doi.org/10.1007/978-1-4899-5760-3, “1988”
(date of publication 22 December 1987; see Loeblich and Tappan, 1989).
Loeblich Jr., A. R. and Tappan, H.: Publication date of “Foraminiferal
genera and their classification”, J. Paleontol., 63, 253, 1989.