Articles | Volume 21, issue 11
https://doi.org/10.5194/bg-21-2877-2024
© 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-21-2877-2024
© 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 Jun 2024
Research article |
| 14 Jun 2024
| 14 Jun 2024
Disentangling influences of climate variability and lake-system evolution on climate proxies derived from isoprenoid and branched glycerol dialkyl glycerol tetraethers (GDGTs): the 250 kyr Lake Chala record
Utrecht University, Faculty of Geosciences, Department of Earth Sciences, Princetonlaan 8A, 3584 CB Utrecht, the Netherlands
Utrecht University, Faculty of Geosciences, Department of Earth Sciences, Princetonlaan 8A, 3584 CB Utrecht, the Netherlands
Dirk Verschuren
Ghent University, Department of Biology, Limnology Unit, K.L. Ledeganckstraat 35, 9000 Gent, Belgium
Aihemaiti Maitituerdi
Dr. Moses Strauss Department of Marine Geosciences, Leon H. Charney School of Marine Sciences, University of Haifa, Mount Carmel 3498838, Israel
Nicolas Waldmann
Dr. Moses Strauss Department of Marine Geosciences, Leon H. Charney School of Marine Sciences, University of Haifa, Mount Carmel 3498838, Israel
Jaap S. Sinninghe Damsté
Utrecht University, Faculty of Geosciences, Department of Earth Sciences, Princetonlaan 8A, 3584 CB Utrecht, the Netherlands
NIOZ Royal Netherlands Institute for Sea Research, Department of Marine Microbiology and Biogeochemistry, P.O. Box 59, 1790 AB, Den Burg, the Netherlands
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Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are used as a paleothermometer based on their temperature dependence in global soils, but aquatic production complicates their use in lakes. BrGDGTs in the water column of Lake Chala, East Africa, respond to oxygen conditions and mixing. Changes in their signal can be linked to bacterial community composition rather than membrane adaptation to changing conditions. Their integrated signal in the sediment reflects mean air temperature.
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Marlow Julius Cramwinckel, Lineke Woelders, Emiel P. Huurdeman, Francien Peterse, Stephen J. Gallagher, Jörg Pross, Catherine E. Burgess, Gert-Jan Reichart, Appy Sluijs, and Peter K. Bijl
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Erin L. McClymont, Heather L. Ford, Sze Ling Ho, Julia C. Tindall, Alan M. Haywood, Montserrat Alonso-Garcia, Ian Bailey, Melissa A. Berke, Kate Littler, Molly O. Patterson, Benjamin Petrick, Francien Peterse, A. Christina Ravelo, Bjørg Risebrobakken, Stijn De Schepper, George E. A. Swann, Kaustubh Thirumalai, Jessica E. Tierney, Carolien van der Weijst, Sarah White, Ayako Abe-Ouchi, Michiel L. J. Baatsen, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Ran Feng, Chuncheng Guo, Anna S. von der Heydt, Stephen Hunter, Xiangyi Li, Gerrit Lohmann, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Christian Stepanek, and Zhongshi Zhang
Clim. Past, 16, 1599–1615, https://doi.org/10.5194/cp-16-1599-2020, https://doi.org/10.5194/cp-16-1599-2020, 2020
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We examine the sea-surface temperature response to an interval of climate ~ 3.2 million years ago, when CO2 concentrations were similar to today and the near future. Our geological data and climate models show that global mean sea-surface temperatures were 2.3 to 3.2 ºC warmer than pre-industrial climate, that the mid-latitudes and high latitudes warmed more than the tropics, and that the warming was particularly enhanced in the North Atlantic Ocean.
Jingjing Guo, Miriam Glendell, Jeroen Meersmans, Frédérique Kirkels, Jack J. Middelburg, and Francien Peterse
Biogeosciences, 17, 3183–3201, https://doi.org/10.5194/bg-17-3183-2020, https://doi.org/10.5194/bg-17-3183-2020, 2020
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Emily Dearing Crampton-Flood, Lars J. Noorbergen, Damian Smits, R. Christine Boschman, Timme H. Donders, Dirk K. Munsterman, Johan ten Veen, Francien Peterse, Lucas Lourens, and Jaap S. Sinninghe Damsté
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Charlotte Miller, Jemma Finch, Trevor Hill, Francien Peterse, Marc Humphries, Matthias Zabel, and Enno Schefuß
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Tamara L. Fletcher, Lisa Warden, Jaap S. Sinninghe Damsté, Kendrick J. Brown, Natalia Rybczynski, John C. Gosse, and Ashley P. Ballantyne
Clim. Past, 15, 1063–1081, https://doi.org/10.5194/cp-15-1063-2019, https://doi.org/10.5194/cp-15-1063-2019, 2019
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Darci Rush, Helen M. Talbot, Marcel T. J. van der Meer, Ellen C. Hopmans, Ben Douglas, and Jaap S. Sinninghe Damsté
Biogeosciences, 16, 2467–2479, https://doi.org/10.5194/bg-16-2467-2019, https://doi.org/10.5194/bg-16-2467-2019, 2019
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Gabriella M. Weiss, David Chivall, Sebastian Kasper, Hideto Nakamura, Fiz da Costa, Philippe Soudant, Jaap S. Sinninghe Damsté, Stefan Schouten, and Marcel T. J. van der Meer
Biogeosciences Discuss., https://doi.org/10.5194/bg-2019-147, https://doi.org/10.5194/bg-2019-147, 2019
Preprint withdrawn
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Marijke W. de Bar, Jenny E. Ullgren, Robert C. Thunnell, Stuart G. Wakeham, Geert-Jan A. Brummer, Jan-Berend W. Stuut, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 16, 1705–1727, https://doi.org/10.5194/bg-16-1705-2019, https://doi.org/10.5194/bg-16-1705-2019, 2019
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We analyzed sediment traps from the Cariaco Basin, the tropical Atlantic and the Mozambique Channel to evaluate seasonal imprints in the concentrations and fluxes of long-chain diols (LDIs), in addition to the long-chain diol index proxy (sea surface temperature proxy) and the diol index (upwelling indicator). Despite significant degradation, LDI-derived temperatures were very similar for the sediment traps and seafloor sediments, and corresponded to annual mean sea surface temperatures.
Peleg Haruzi, Regina Katsman, Baruch Spiro, Matthias Halisch, and Nicolas Waldmann
Solid Earth Discuss., https://doi.org/10.5194/se-2019-21, https://doi.org/10.5194/se-2019-21, 2019
Revised manuscript not accepted
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We studied petrophysical characteristics of three consecutive sandstone layers of the Lower Cretaceous Hatira Formation from Israel. Evaluated micro- and macro-scale petrophysical properties predetermined the permeability of the layers, measured in turn in the lab and upscaled from pore-scale velocities. Two scales of porosity variations were found: at 300 μm scale due to pores size variability, and at 2 mm scale due to high and low porosity occlusions, suggested to control the permeability.
Marijke W. de Bar, Dave J. Stolwijk, Jerry F. McManus, Jaap S. Sinninghe Damsté, and Stefan Schouten
Clim. Past, 14, 1783–1803, https://doi.org/10.5194/cp-14-1783-2018, https://doi.org/10.5194/cp-14-1783-2018, 2018
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We present a past sea surface temperature and paleoproductivity record over the last 150 000 years for ODP Site 1234 (Chilean margin). We tested the applicability of long-chain diol proxies for the reconstrucion of SST (LDI), past upwelling conditions (diol index), and nutrient concentrations (NDI). The LDI likely reflects past temperature changes, but the diol index and NDI are perhaps more indicative of Proboscia diatom productivity rather than upwelling and/or nutrient conditions.
Florence Sylvestre, Mathieu Schuster, Hendrik Vogel, Moussa Abdheramane, Daniel Ariztegui, Ulrich Salzmann, Antje Schwalb, Nicolas Waldmann, and the ICDP CHADRILL Consortium
Sci. Dril., 24, 71–78, https://doi.org/10.5194/sd-24-71-2018, https://doi.org/10.5194/sd-24-71-2018, 2018
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CHADRILL aims to recover a sedimentary core spanning the Miocene–Pleistocene sediment succession of Lake Chad through deep drilling. This record will provide significant insights into the modulation of orbitally forced changes in northern African hydroclimate under different climate boundary conditions and the most continuous climatic and environmental record to be compared with hominid migrations across northern Africa and the implications for understanding human evolution.
Loeka L. Jongejans, Jens Strauss, Josefine Lenz, Francien Peterse, Kai Mangelsdorf, Matthias Fuchs, and Guido Grosse
Biogeosciences, 15, 6033–6048, https://doi.org/10.5194/bg-15-6033-2018, https://doi.org/10.5194/bg-15-6033-2018, 2018
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Arctic warming mobilizes belowground organic matter in northern high latitudes. This study focused on the size of organic carbon pools and organic matter quality in ice-rich permafrost on the Baldwin Peninsula, West Alaska. We analyzed biogeochemistry and found that three-quarters of the carbon is stored in degraded permafrost deposits. Nonetheless, using biomarker analyses, we showed that the organic matter in undisturbed yedoma permafrost has a higher potential for decomposition.
Sergio Balzano, Julie Lattaud, Laura Villanueva, Sebastiaan W. Rampen, Corina P. D. Brussaard, Judith van Bleijswijk, Nicole Bale, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 5951–5968, https://doi.org/10.5194/bg-15-5951-2018, https://doi.org/10.5194/bg-15-5951-2018, 2018
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We tried to identify the microbes which biosynthesize a class of lipids widespread in seawater, the long chain alkyl diols (LCDs). We could not find any microorganism likely involved in the production of LCDs. The amounts of LCDs found are too high to be produced by living organisms and are likely to be part of the refractory organic matter persisting for long periods in the water column.
Julian D. Hartman, Francesca Sangiorgi, Ariadna Salabarnada, Francien Peterse, Alexander J. P. Houben, Stefan Schouten, Henk Brinkhuis, Carlota Escutia, and Peter K. Bijl
Clim. Past, 14, 1275–1297, https://doi.org/10.5194/cp-14-1275-2018, https://doi.org/10.5194/cp-14-1275-2018, 2018
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We reconstructed sea surface temperatures for the Oligocene and Miocene periods (34–11 Ma) based on archaeal lipids from a site close to the Wilkes Land coast, Antarctica. Our record suggests generally warm to temperate surface waters: on average 17 °C. Based on the lithology, glacial and interglacial temperatures could be distinguished, showing an average 3 °C offset. The long-term temperature trend resembles the benthic δ18O stack, which may have implications for ice volume reconstructions.
Julie Lattaud, Frédérique Kirkels, Francien Peterse, Chantal V. Freymond, Timothy I. Eglinton, Jens Hefter, Gesine Mollenhauer, Sergio Balzano, Laura Villanueva, Marcel T. J. van der Meer, Ellen C. Hopmans, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 4147–4161, https://doi.org/10.5194/bg-15-4147-2018, https://doi.org/10.5194/bg-15-4147-2018, 2018
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Long-chain diols (LCDs) are biomarkers that occur widespread in marine environments and also in lakes and rivers. In this study, we looked at the distribution of LCDs in three river systems (Godavari, Danube, and Rhine) in relation to season, precipitation, and temperature. We found out that the LCDs are likely being produced in calm areas of the river systems and that marine LCDs have a different distribution than riverine LCDs.
Marc A. Besseling, Ellen C. Hopmans, R. Christine Boschman, Jaap S. Sinninghe Damsté, and Laura Villanueva
Biogeosciences, 15, 4047–4064, https://doi.org/10.5194/bg-15-4047-2018, https://doi.org/10.5194/bg-15-4047-2018, 2018
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Benthic archaea comprise a significant part of the total prokaryotic biomass in marine sediments. Here, we compared the archaeal diversity and intact polar lipid (IPL) composition in both surface and subsurface sediments with different oxygen regimes in the Arabian Sea oxygen minimum zone. The oxygenated sediments were dominated by Thaumarchaeota and IPL-GDGT-0. The anoxic sediment contained highly diverse archaeal communities and high relative abundances of IPL-GDGT-1 to -4.
Muhammed Ojoshogu Usman, Frédérique Marie Sophie Anne Kirkels, Huub Michel Zwart, Sayak Basu, Camilo Ponton, Thomas Michael Blattmann, Michael Ploetze, Negar Haghipour, Cameron McIntyre, Francien Peterse, Maarten Lupker, Liviu Giosan, and Timothy Ian Eglinton
Biogeosciences, 15, 3357–3375, https://doi.org/10.5194/bg-15-3357-2018, https://doi.org/10.5194/bg-15-3357-2018, 2018
Timme H. Donders, Niels A. G. M. van Helmond, Roel Verreussel, Dirk Munsterman, Johan ten Veen, Robert P. Speijer, Johan W. H. Weijers, Francesca Sangiorgi, Francien Peterse, Gert-Jan Reichart, Jaap S. Sinninghe Damsté, Lucas Lourens, Gesa Kuhlmann, and Henk Brinkhuis
Clim. Past, 14, 397–411, https://doi.org/10.5194/cp-14-397-2018, https://doi.org/10.5194/cp-14-397-2018, 2018
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The buildup and melting of ice during the early glaciations in the Northern Hemisphere, around 2.5 million years ago, were far shorter in duration than during the last million years. Based on molecular compounds and microfossils from sediments dating back to the early glaciations we show that the temperature on land and in the sea changed simultaneously and was a major factor in the ice buildup in the Northern Hemisphere. These data provide key insights into the dynamics of early glaciations.
Nicole J. Bale, Tracy A. Villareal, Ellen C. Hopmans, Corina P. D. Brussaard, Marc Besseling, Denise Dorhout, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 1229–1241, https://doi.org/10.5194/bg-15-1229-2018, https://doi.org/10.5194/bg-15-1229-2018, 2018
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Associations between diatoms and N-fixing cyanobacteria (diatom–diazotroph associations, DDAs) play an important role in the N cycle of the tropical North Atlantic. Heterocysts are the site of N fixation and contain unique glycolipids. We measured these glycolipids in the water column and surface sediment from the tropical North Atlantic. We found a significant correlation between the concentration of glycolipid and of DDAs, strengthening their application as biomarkers.
Martina Sollai, Ellen C. Hopmans, Nicole J. Bale, Anchelique Mets, Lisa Warden, Matthias Moros, and Jaap S. Sinninghe Damsté
Biogeosciences, 14, 5789–5804, https://doi.org/10.5194/bg-14-5789-2017, https://doi.org/10.5194/bg-14-5789-2017, 2017
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The Baltic Sea is characterized by recurring summer phytoplankton blooms, dominated by a few cyanobacterial species. These bacteria are able to use dinitrogen gas as the source for nitrogen and produce very specific lipids. We analyzed these lipids in a sediment core to study their presence over the past 7000 years. This reveals that cyanobacterial blooms have not only occurred in the last decades but were common at times when the Baltic was connected to the North Sea.
Gabriella M. Weiss, Eva Y. Pfannerstill, Stefan Schouten, Jaap S. Sinninghe Damsté, and Marcel T. J. van der Meer
Biogeosciences, 14, 5693–5704, https://doi.org/10.5194/bg-14-5693-2017, https://doi.org/10.5194/bg-14-5693-2017, 2017
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Algal-derived compounds allow us to make assumptions about environmental conditions in the past. In order to better understand how organisms record environmental conditions, we grew microscopic marine algae at different light intensities, salinities, and alkalinities in a temperature-controlled environment. We determined how these environmental parameters affected specific algal-derived compounds, especially their relative deuterium content, which seems to be mainly affected by salinity.
Julie Lattaud, Denise Dorhout, Hartmut Schulz, Isla S. Castañeda, Enno Schefuß, Jaap S. Sinninghe Damsté, and Stefan Schouten
Clim. Past, 13, 1049–1061, https://doi.org/10.5194/cp-13-1049-2017, https://doi.org/10.5194/cp-13-1049-2017, 2017
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The study of past sedimentary records from coastal margins allows us to reconstruct variations in terrestrial input into the marine realm and to gain insight into continental climatic variability. The study of two sediment cores close to river mouths allowed us to show the potential of long-chain diols as riverine input proxy.
Lien De Wispelaere, Samuel Bodé, Pedro Hervé-Fernández, Andreas Hemp, Dirk Verschuren, and Pascal Boeckx
Biogeosciences, 14, 73–88, https://doi.org/10.5194/bg-14-73-2017, https://doi.org/10.5194/bg-14-73-2017, 2017
Lisa Warden, Jung-Hyun Kim, Claudia Zell, Geert-Jan Vis, Henko de Stigter, Jérôme Bonnin, and Jaap S. Sinninghe Damsté
Biogeosciences, 13, 5719–5738, https://doi.org/10.5194/bg-13-5719-2016, https://doi.org/10.5194/bg-13-5719-2016, 2016
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Enhanced analytical techniques were applied to characterize fossilized microbial cell membrane lipids from samples in the Tagus River basin spanning the last 6000 years. Using the novel methods and calibration, the pH estimates were improved upon, and this study reveals new factors that should be considered when using this proxy as well as affirms the importance of examining the provenance of these lipids before applying them for paleoclimate reconstructions.
Sandra Mariam Heinzelmann, Nicole Jane Bale, Laura Villanueva, Danielle Sinke-Schoen, Catharina Johanna Maria Philippart, Jaap Smede Sinninghe Damsté, Stefan Schouten, and Marcel Teunis Jan van der Meer
Biogeosciences, 13, 5527–5539, https://doi.org/10.5194/bg-13-5527-2016, https://doi.org/10.5194/bg-13-5527-2016, 2016
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In order to understand microbial communities in the environment it is necessary to assess their metabolic potential. The hydrogen isotopic composition of fatty acids has been shown to be promising tool to study the general metabolism of microorganisms in pure culture. Here we showed that it is possible to study seasonal changes in the general metabolism of the whole community by studying the hydrogen isotopic composition of fatty acids.
François Klein, Hugues Goosse, Nicholas E. Graham, and Dirk Verschuren
Clim. Past, 12, 1499–1518, https://doi.org/10.5194/cp-12-1499-2016, https://doi.org/10.5194/cp-12-1499-2016, 2016
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This paper analyses global climate model simulations of long-term East African hydroclimate changes relative to proxy-based reconstructions over the last millennium. No common signal is found between model results and reconstructions as well as among the model time series, which suggests that simulated hydroclimate is mostly driven by internal variability rather than by common external forcing.
Laura K. Buckles, Dirk Verschuren, Johan W. H. Weijers, Christine Cocquyt, Maarten Blaauw, and Jaap S. Sinninghe Damsté
Clim. Past, 12, 1243–1262, https://doi.org/10.5194/cp-12-1243-2016, https://doi.org/10.5194/cp-12-1243-2016, 2016
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This paper discusses the underlying mechanisms of a method that uses specific membrane lipids present in the sediments of an African tropical lake to determine past changes in rainfall. With this method, past dry periods in the last 25 000 years can be assessed.
Douwe S. Maat, Nicole J. Bale, Ellen C. Hopmans, Jaap S. Sinninghe Damsté, Stefan Schouten, and Corina P. D. Brussaard
Biogeosciences, 13, 1667–1676, https://doi.org/10.5194/bg-13-1667-2016, https://doi.org/10.5194/bg-13-1667-2016, 2016
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This study shows that the phytoplankter Micromonas pusilla alters its lipid composition when the macronutrient phosphate is in low supply. This reduction in phospholipids is directly dependent on the strength of the limitation. Furthermore we show that, when M. pusilla is infected by viruses, lipid remodeling is lower. The study was carried out to investigate how phytoplankton and its viruses are affected by environmental factors and how this affects food web dynamics.
I. Neugebauer, M. J. Schwab, N. D. Waldmann, R. Tjallingii, U. Frank, E. Hadzhiivanova, R. Naumann, N. Taha, A. Agnon, Y. Enzel, and A. Brauer
Clim. Past, 12, 75–90, https://doi.org/10.5194/cp-12-75-2016, https://doi.org/10.5194/cp-12-75-2016, 2016
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Micro-facies changes and elemental variations in deep Dead Sea sediments are used to reconstruct relative lake level changes for the early last glacial period. The results indicate a close link of hydroclimatic variability in the Levant to North Atlantic-Mediterranean climates during the time of the build-up of Northern Hemisphere ice shields. First petrographic analyses of gravels in the deep core question the recent hypothesis of a Dead Sea dry-down at the end of the last interglacial.
F. Peterse, C. M. Moy, and T. I. Eglinton
Biogeosciences, 12, 933–943, https://doi.org/10.5194/bg-12-933-2015, https://doi.org/10.5194/bg-12-933-2015, 2015
I. Ssemmanda, V. Gelorini, and D. Verschuren
Clim. Past, 10, 2067–2080, https://doi.org/10.5194/cp-10-2067-2014, https://doi.org/10.5194/cp-10-2067-2014, 2014
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Using fossil pollen assemblages to trace vegetation response to relatively modest historical climate fluctuations is difficult. In this study, pollen data from a lake-sediment record in Queen Elizabeth National Park (Uganda) show that its landscape has been an open wooded savannah throughout the past 200 years, with known historical moisture-balance variation exerting modest effects on local tree cover (mostly Acacia and Ficus) and the occurrence of damp soil areas (promoting Phoenix palms).
Related subject area
Paleobiogeoscience: Proxy use, Development & Validation
Phylogeochemistry: exploring evolutionary constraints on belemnite rostrum element composition
Reconstructing central African hydroclimate over the past century using freshwater bivalve shell geochemistry
Effects of photosymbiosis and related processes on planktic foraminifera-bound nitrogen isotopes in South Atlantic sediments
Exploring macroevolutionary links in multi-species planktonic foraminiferal Mg∕Ca and δ18O from 15 Ma to recent
Reviews and syntheses: Review of proxies for low-oxygen paleoceanographic reconstructions
A long-term drought reconstruction based on oxygen isotope tree ring data for central and eastern parts of Europe (Romania)
Deep-sea stylasterid δ18O and δ13C maps inform sampling scheme for paleotemperature reconstructions
European forest cover during the Holocene reconstructed from pollen records
Electron backscatter diffraction analysis unveils foraminiferal calcite microstructure and processes of diagenetic alteration
Quantifying the δ15N trophic offset in a cold-water scleractinian coral (CWC): implications for the CWC diet and coral δ15N as a marine N cycle proxy
Stable oxygen isotopes of crocodilian tooth enamel allow tracking Plio-Pleistocene evolution of freshwater environments and climate in the Shungura Formation (Turkana Depression, Ethiopia)
Charcoal morphologies and morphometrics of a Eurasian grass-dominated system for robust interpretation of past fuel and fire type
Single-species dinoflagellate cyst carbon isotope fractionation in core-top sediments: environmental controls, CO2 dependency and proxy potential
Past fire dynamics inferred from polycyclic aromatic hydrocarbons and monosaccharide anhydrides in a stalagmite from the archaeological site of Mayapan, Mexico
Examination of the parameters controlling the triple oxygen isotope composition of grass leaf water and phytoliths at a Mediterranean site: a model–data approach
Biomarker characterization of the North Water Polynya, Baffin Bay: implications for local sea ice and temperature proxies
Technical note: No impact of alkenone extraction on foraminiferal stable isotope, trace element and boron isotope geochemistry
Experimental burial diagenesis of aragonitic biocarbonates: from organic matter loss to abiogenic calcite formation
A modern snapshot of the isotopic composition of lacustrine biogenic carbonates – records of seasonal water temperature variability
Performance of temperature and productivity proxies based on long-chain alkane-1, mid-chain diols at test: a 5-year sediment trap record from the Mauritanian upwelling
Validation of a coupled δ2Hn-alkane–δ18Osugar paleohygrometer approach based on a climate chamber experiment
Experimental production of charcoal morphologies to discriminate fuel source and fire type: an example from Siberian taiga
Toward a global calibration for quantifying past oxygenation in oxygen minimum zones using benthic Foraminifera
Calibration of Mg ∕ Ca and Sr ∕ Ca in coastal marine ostracods as a proxy for temperature
Technical note: Accelerate coccolith size separation via repeated centrifugation
Mg∕Ca, Sr∕Ca and stable isotopes from the planktonic foraminifera T. sacculifer: testing a multi-proxy approach for inferring paleotemperature and paleosalinity
Chemical destaining and the delta correction for blue intensity measurements of stained lake subfossil trees
Modern calibration of Poa flabellata (tussac grass) as a new paleoclimate proxy in the South Atlantic
Seawater pH reconstruction using boron isotopes in multiple planktonic foraminifera species with different depth habitats and their potential to constrain pH and pCO2 gradients
Bottom-water deoxygenation at the Peruvian margin during the last deglaciation recorded by benthic foraminifera
The pH dependency of the boron isotopic composition of diatom opal (Thalassiosira weissflogii)
Benthic foraminifera as tracers of brine production in the Storfjorden “sea ice factory”
Evaluation of bacterial glycerol dialkyl glycerol tetraether and 2H–18O biomarker proxies along a central European topsoil transect
Leaf wax n-alkane patterns and compound-specific δ13C of plants and topsoils from semi-arid and arid Mongolia
Organic-carbon-rich sediments: benthic foraminifera as bio-indicators of depositional environments
Strong correspondence between nitrogen isotope composition of foliage and chlorin across a rainfall gradient: implications for paleo-reconstruction of the nitrogen cycle
Environmental and biological controls on Na∕Ca ratios in scleractinian cold-water corals
Depth habitat of the planktonic foraminifera Neogloboquadrina pachyderma in the northern high latitudes explained by sea-ice and chlorophyll concentrations
Temporal variability in foraminiferal morphology and geochemistry at the West Antarctic Peninsula: a sediment trap study
Seasonality of archaeal lipid flux and GDGT-based thermometry in sinking particles of high-latitude oceans: Fram Strait (79° N) and Antarctic Polar Front (50° S)
Long-chain diols in settling particles in tropical oceans: insights into sources, seasonality and proxies
Multi-trace-element sea surface temperature coral reconstruction for the southern Mozambique Channel reveals teleconnections with the tropical Atlantic
Oxygen isotope composition of the final chamber of planktic foraminifera provides evidence of vertical migration and depth-integrated growth
Mg ∕ Ca and δ18O in living planktic foraminifers from the Caribbean, Gulf of Mexico and Florida Straits
Manganese incorporation in living (stained) benthic foraminiferal shells: a bathymetric and in-sediment study in the Gulf of Lions (NW Mediterranean)
Effects of light and temperature on Mg uptake, growth, and calcification in the proxy climate archive Clathromorphum compactum
A systematic look at chromium isotopes in modern shells – implications for paleo-environmental reconstructions
Reviews and syntheses: Revisiting the boron systematics of aragonite and their application to coral calcification
Physico-chemical and biological factors influencing dinoflagellate cyst production in the Cariaco Basin
Effects of alkalinity and salinity at low and high light intensity on hydrogen isotope fractionation of long-chain alkenones produced by Emiliania huxleyi
Alexander Pohle, Kevin Stevens, René Hoffmann, and Adrian Immenhauser
Biogeosciences, 22, 3073–3102, https://doi.org/10.5194/bg-22-3073-2025, https://doi.org/10.5194/bg-22-3073-2025, 2025
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Belemnite rostrum geochemistry is used as a proxy in palaeoceanography. Evolutionary patterns in element ratios (Mg/Ca, Sr/Ca, Mn/Ca, and Fe/Ca) from belemnite rostra based on a literature dataset are assessed. These proxy data reflect a complex interplay between evolutionary, ontogenetic, environmental, kinetic, and diagenetic effects. We coin the new term “phylogeochemistry” for this interdisciplinary research field.
Zita Kelemen, David P. Gillikin, and Steven Bouillon
Biogeosciences, 22, 2621–2635, https://doi.org/10.5194/bg-22-2621-2025, https://doi.org/10.5194/bg-22-2621-2025, 2025
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We analysed the C and O stable isotope composition (δ13C, δ18O) across the growth axis of museum-archived and recent Chambardia wissmanni shells from the Oubangui River (Congo basin) covering sections of the past ~120 years. Recent shells showed a much wider range of δ18O values compared to historical specimens, consistent with the suggestion that dry periods in the upper Congo basin have become more extreme in recent times and highlighting the potential of this species to reconstruct hydroclimatic conditions.
Alexandra Auderset, Sandi M. Smart, Yeongjun Ryu, Dario Marconi, Haojia Abby Ren, Lena Heins, Hubert Vonhof, Ralf Schiebel, Janne Repschläger, Daniel M. Sigman, Gerald H. Haug, and Alfredo Martínez-García
Biogeosciences, 22, 1887–1905, https://doi.org/10.5194/bg-22-1887-2025, https://doi.org/10.5194/bg-22-1887-2025, 2025
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This study uses foraminifera-bound nitrogen isotopes (FB-δ15N) to investigate photosymbiosis in planktic foraminifera. The analysis of South Atlantic shells, compared to a global dataset, shows that FB-δ15N distinguishes species with certain algal symbionts (dinoflagellates), likely due to internal ammonium recycling. However, the studied site stands out with its larger-than-expected FB-δ15N offsets, highlighting influences on FB-δ15N signatures in regions with strong environmental gradients.
Flavia Boscolo-Galazzo, David Evans, Elaine M. Mawbey, William R. Gray, Paul N. Pearson, and Bridget S. Wade
Biogeosciences, 22, 1095–1113, https://doi.org/10.5194/bg-22-1095-2025, https://doi.org/10.5194/bg-22-1095-2025, 2025
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Here we compare the Mg / Ca and oxygen isotope signatures for 57 recent to fossil species of planktonic foraminifera for the last 15 Myr. We find the occurrence of lineage-specific offsets in Mg / Ca conservative between ancestor-descendent species. Taking into account species kinship significantly improves temperature reconstructions, and we suggest that the occurrence of Mg / Ca offsets in modern species results from their evolution when ocean properties were different from today's.
Babette A.A. Hoogakker, Catherine Davis, Yi Wang, Stephanie Kusch, Katrina Nilsson-Kerr, Dalton S. Hardisty, Allison Jacobel, Dharma Reyes Macaya, Nicolaas Glock, Sha Ni, Julio Sepúlveda, Abby Ren, Alexandra Auderset, Anya V. Hess, Katrin J. Meissner, Jorge Cardich, Robert Anderson, Christine Barras, Chandranath Basak, Harold J. Bradbury, Inda Brinkmann, Alexis Castillo, Madelyn Cook, Kassandra Costa, Constance Choquel, Paula Diz, Jonas Donnenfield, Felix J. Elling, Zeynep Erdem, Helena L. Filipsson, Sebastián Garrido, Julia Gottschalk, Anjaly Govindankutty Menon, Jeroen Groeneveld, Christian Hallmann, Ingrid Hendy, Rick Hennekam, Wanyi Lu, Jean Lynch-Stieglitz, Lélia Matos, Alfredo Martínez-García, Giulia Molina, Práxedes Muñoz, Simone Moretti, Jennifer Morford, Sophie Nuber, Svetlana Radionovskaya, Morgan Reed Raven, Christopher J. Somes, Anja S. Studer, Kazuyo Tachikawa, Raúl Tapia, Martin Tetard, Tyler Vollmer, Xingchen Wang, Shuzhuang Wu, Yan Zhang, Xin-Yuan Zheng, and Yuxin Zhou
Biogeosciences, 22, 863–957, https://doi.org/10.5194/bg-22-863-2025, https://doi.org/10.5194/bg-22-863-2025, 2025
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Paleo-oxygen proxies can extend current records, constrain pre-anthropogenic baselines, provide datasets necessary to test climate models under different boundary conditions, and ultimately understand how ocean oxygenation responds on longer timescales. Here we summarize current proxies used for the reconstruction of Cenozoic seawater oxygen levels. This includes an overview of the proxy's history, how it works, resources required, limitations, and future recommendations.
Viorica Nagavciuc, Gerhard Helle, Maria Rădoane, Cătălin-Constantin Roibu, Mihai-Gabriel Cotos, and Monica Ionita
Biogeosciences, 22, 55–69, https://doi.org/10.5194/bg-22-55-2025, https://doi.org/10.5194/bg-22-55-2025, 2025
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We reconstructed drought conditions for the past 200 years for central and eastern parts of Europe (Romania) using δ18O in oak tree ring cellulose from Romania, revealing periods of both extreme wetness (e.g., 1905–1915) and dryness (e.g., 1818–1835). The most severe droughts occurred in the 19th and 21st centuries, likely linked to large-scale atmospheric circulation. This research highlights the potential of tree rings to improve our understanding of long-term climate variability in Europe.
Theresa M. King, Brad E. Rosenheim, and Noel P. James
Biogeosciences, 21, 5361–5379, https://doi.org/10.5194/bg-21-5361-2024, https://doi.org/10.5194/bg-21-5361-2024, 2024
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Corals can record ocean properties such as temperature in their skeletons. These records are useful for where and when we have no instrumental record like in the distant past. However, coral growth must be understood to interpret these records. Here, we analyze slices of a branching deep-sea coral from Antarctica to determine how to best sample these corals for past-climate work. We recommend sampling from the innermost portion of a coral skeleton for accurate temperature reconstructions.
Luke Fionn Sweeney, Sandy P. Harrison, and Marc Vander Linden
EGUsphere, https://doi.org/10.5194/egusphere-2024-1523, https://doi.org/10.5194/egusphere-2024-1523, 2024
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Changes in tree cover across Europe during the Holocene are reconstructed from fossil pollen data using a model developed with modern observations of tree cover and modern pollen assemblages. There is a rapid increase in tree cover after the last glacial with maximum cover during the mid-Holocene and a decline thereafter; the timing of the maximum and the speed of the increase and subsequent decrease vary regionally likely reflecting differences in climate trajectories and human influence.
Frances A. Procter, Sandra Piazolo, Eleanor H. John, Richard Walshaw, Paul N. Pearson, Caroline H. Lear, and Tracy Aze
Biogeosciences, 21, 1213–1233, https://doi.org/10.5194/bg-21-1213-2024, https://doi.org/10.5194/bg-21-1213-2024, 2024
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This study uses novel techniques to look at the microstructure of planktonic foraminifera (single-celled marine organisms) fossils, to further our understanding of how they form their hard exterior shells and how the microstructure and chemistry of these shells can change as a result of processes that occur after deposition on the seafloor. Understanding these processes is of critical importance for using planktonic foraminifera for robust climate and environmental reconstructions of the past.
Josie L. Mottram, Anne M. Gothmann, Maria G. Prokopenko, Austin Cordova, Veronica Rollinson, Katie Dobkowski, and Julie Granger
Biogeosciences, 21, 1071–1091, https://doi.org/10.5194/bg-21-1071-2024, https://doi.org/10.5194/bg-21-1071-2024, 2024
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Knowledge of ancient ocean N cycling can help illuminate past climate change. Using field and lab studies, this work ground-truths a promising proxy for marine N cycling, the N isotope composition of cold-water coral (CWC) skeletons. Our results estimate N turnover in CWC tissue; quantify the isotope effects between CWC tissue, diet, and skeleton; and suggest that CWCs possibly feed mainly on metazoan zooplankton, suggesting that the marine N proxy may be sensitive to the food web structure.
Axelle Gardin, Emmanuelle Pucéat, Géraldine Garcia, Jean-Renaud Boisserie, Adélaïde Euriat, Michael M. Joachimski, Alexis Nutz, Mathieu Schuster, and Olga Otero
Biogeosciences, 21, 437–454, https://doi.org/10.5194/bg-21-437-2024, https://doi.org/10.5194/bg-21-437-2024, 2024
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We introduce a novel approach using stable oxygen isotopes from crocodilian fossil teeth to unravel palaeohydrological changes in past continental contexts. Applying it to the Plio-Pleistocene Ethiopian Shungura Formation, we found a significant increase in δ18O in the last 3 million years, likely due to monsoonal shifts and reduced rainfall, and that the local diversity of waterbodies (lakes, rivers, ponds) became restricted.
Angelica Feurdean, Richard S. Vachula, Diana Hanganu, Astrid Stobbe, and Maren Gumnior
Biogeosciences, 20, 5069–5085, https://doi.org/10.5194/bg-20-5069-2023, https://doi.org/10.5194/bg-20-5069-2023, 2023
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This paper presents novel results of laboratory-produced charcoal forms from various grass, forb and shrub taxa from the Eurasian steppe to facilitate more robust interpretations of fuel sources and fire types in grassland-dominated ecosystems. Advancements in identifying fuel sources and changes in fire types make charcoal analysis relevant to studies of plant evolution and fire management.
Joost Frieling, Linda van Roij, Iris Kleij, Gert-Jan Reichart, and Appy Sluijs
Biogeosciences, 20, 4651–4668, https://doi.org/10.5194/bg-20-4651-2023, https://doi.org/10.5194/bg-20-4651-2023, 2023
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We present a first species-specific evaluation of marine core-top dinoflagellate cyst carbon isotope fractionation (εp) to assess natural pCO2 dependency on εp and explore its geological deep-time paleo-pCO2 proxy potential. We find that εp differs between genera and species and that in Operculodinium centrocarpum, εp is controlled by pCO2 and nutrients. Our results highlight the added value of δ13C analyses of individual micrometer-scale sedimentary organic carbon particles.
Julia Homann, Niklas Karbach, Stacy A. Carolin, Daniel H. James, David Hodell, Sebastian F. M. Breitenbach, Ola Kwiecien, Mark Brenner, Carlos Peraza Lope, and Thorsten Hoffmann
Biogeosciences, 20, 3249–3260, https://doi.org/10.5194/bg-20-3249-2023, https://doi.org/10.5194/bg-20-3249-2023, 2023
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Cave stalagmites contain substances that can be used to reconstruct past changes in local and regional environmental conditions. We used two classes of biomarkers (polycyclic aromatic hydrocarbons and monosaccharide anhydrides) to detect the presence of fire and to also explore changes in fire regime (e.g. fire frequency, intensity, and fuel source). We tested our new method on a stalagmite from Mayapan, a large Maya city on the Yucatán Peninsula.
Claudia Voigt, Anne Alexandre, Ilja M. Reiter, Jean-Philippe Orts, Christine Vallet-Coulomb, Clément Piel, Jean-Charles Mazur, Julie C. Aleman, Corinne Sonzogni, Helene Miche, and Jérôme Ogée
Biogeosciences, 20, 2161–2187, https://doi.org/10.5194/bg-20-2161-2023, https://doi.org/10.5194/bg-20-2161-2023, 2023
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Data on past relative humidity (RH) ARE needed to improve its representation in Earth system models. A novel isotope parameter (17O-excess) of plant silica has been developed to quantify past RH. Using comprehensive monitoring and novel methods, we show how environmental and plant physiological parameters influence the 17O-excess of plant silica and leaf water, i.e. its source water. The insights gained from this study will help to improve estimates of RH from fossil plant silica deposits.
David J. Harning, Brooke Holman, Lineke Woelders, Anne E. Jennings, and Julio Sepúlveda
Biogeosciences, 20, 229–249, https://doi.org/10.5194/bg-20-229-2023, https://doi.org/10.5194/bg-20-229-2023, 2023
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In order to better reconstruct the geologic history of the North Water Polynya, we provide modern validations and calibrations of lipid biomarker proxies in Baffin Bay. We find that sterols, rather than HBIs, most accurately capture the current extent of the North Water Polynya and will be a valuable tool to reconstruct its past presence or absence. Our local temperature calibrations for GDGTs and OH-GDGTs reduce the uncertainty present in global temperature calibrations.
Jessica G. M. Crumpton-Banks, Thomas Tanner, Ivan Hernández Almeida, James W. B. Rae, and Heather Stoll
Biogeosciences, 19, 5633–5644, https://doi.org/10.5194/bg-19-5633-2022, https://doi.org/10.5194/bg-19-5633-2022, 2022
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Past ocean carbon is reconstructed using proxies, but it is unknown whether preparing ocean sediment for one proxy might damage the data given by another. We have tested whether the extraction of an organic proxy archive from sediment samples impacts the geochemistry of tiny shells also within the sediment. We find no difference in shell geochemistry between samples which come from treated and untreated sediment. This will help us to maximize scientific return from valuable sediment samples.
Pablo Forjanes, María Simonet Roda, Martina Greiner, Erika Griesshaber, Nelson A. Lagos, Sabino Veintemillas-Verdaguer, José Manuel Astilleros, Lurdes Fernández-Díaz, and Wolfgang W. Schmahl
Biogeosciences, 19, 3791–3823, https://doi.org/10.5194/bg-19-3791-2022, https://doi.org/10.5194/bg-19-3791-2022, 2022
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Aragonitic skeletons are employed to decipher past climate dynamics and environmental change. Unfortunately, the information that these skeletons keep can be destroyed during diagenesis. In this work, we study the first changes undergone by aragonitic skeletons upon hydrothermal alteration. We observe that major changes occur from the very beginning of the alteration, even without mineralogical changes. These results have major implications for the use of these archives to understand the past.
Inga Labuhn, Franziska Tell, Ulrich von Grafenstein, Dan Hammarlund, Henning Kuhnert, and Bénédicte Minster
Biogeosciences, 19, 2759–2777, https://doi.org/10.5194/bg-19-2759-2022, https://doi.org/10.5194/bg-19-2759-2022, 2022
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This study presents the isotopic composition of recent biogenic carbonates from several lacustrine species which calcify during different times of the year. The authors demonstrate that when biological offsets are corrected, the dominant cause of differences between species is the seasonal variation in temperature-dependent fractionation of oxygen isotopes. Consequently, such carbonates from lake sediments can provide proxy records of seasonal water temperature changes in the past.
Gerard J. M. Versteegh, Karin A. F. Zonneveld, Jens Hefter, Oscar E. Romero, Gerhard Fischer, and Gesine Mollenhauer
Biogeosciences, 19, 1587–1610, https://doi.org/10.5194/bg-19-1587-2022, https://doi.org/10.5194/bg-19-1587-2022, 2022
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A 5-year record of long-chain mid-chain diol export flux and composition is presented with a 1- to 3-week resolution sediment trap CBeu (in the NW African upwelling). All environmental parameters as well as the diol composition are dominated by the seasonal cycle, albeit with different phase relations for temperature and upwelling. Most diol-based proxies are dominated by upwelling. The long-chain diol index reflects temperatures of the oligotrophic summer sea surface.
Johannes Hepp, Christoph Mayr, Kazimierz Rozanski, Imke Kathrin Schäfer, Mario Tuthorn, Bruno Glaser, Dieter Juchelka, Willibald Stichler, Roland Zech, and Michael Zech
Biogeosciences, 18, 5363–5380, https://doi.org/10.5194/bg-18-5363-2021, https://doi.org/10.5194/bg-18-5363-2021, 2021
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Deriving more quantitative climate information like relative air humidity is one of the key challenges in paleostudies. Often only qualitative reconstructions can be done when single-biomarker-isotope data are derived from a climate archive. However, the coupling of hemicellulose-derived sugar with leaf-wax-derived n-alkane isotope results has the potential to overcome this limitation and allow a quantitative relative air humidity reconstruction.
Angelica Feurdean
Biogeosciences, 18, 3805–3821, https://doi.org/10.5194/bg-18-3805-2021, https://doi.org/10.5194/bg-18-3805-2021, 2021
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This study characterized the diversity of laboratory-produced charcoal morphological features of various fuel types from Siberia at different temperatures. The results obtained improve the attribution of charcoal particles to fuel types and fire characteristics. This work also provides recommendations for the application of this information to refine the past wildfire history.
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
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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.
Maximiliano Rodríguez and Christelle Not
Biogeosciences, 18, 1987–2001, https://doi.org/10.5194/bg-18-1987-2021, https://doi.org/10.5194/bg-18-1987-2021, 2021
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Mg/Ca in calcium carbonate shells of marine organisms such as foraminifera and ostracods has been used as a proxy to reconstruct water temperature. Here we provide new Mg/Ca–temperature calibrations for two shallow marine species of ostracods. We show that the water temperature in spring produces the best calibrations, which suggests the potential use of ostracod shells to reconstruct this parameter at a seasonal scale.
Hongrui Zhang, Chuanlian Liu, Luz María Mejía, and Heather Stoll
Biogeosciences, 18, 1909–1916, https://doi.org/10.5194/bg-18-1909-2021, https://doi.org/10.5194/bg-18-1909-2021, 2021
Delphine Dissard, Gert Jan Reichart, Christophe Menkes, Morgan Mangeas, Stephan Frickenhaus, and Jelle Bijma
Biogeosciences, 18, 423–439, https://doi.org/10.5194/bg-18-423-2021, https://doi.org/10.5194/bg-18-423-2021, 2021
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Results from a data set acquired from living foraminifera T. sacculifer collected from surface waters are presented, allowing us to establish a new Mg/Ca–Sr/Ca–temperature equation improving temperature reconstructions. When combining equations, δ18Ow can be reconstructed with a precision of ± 0.5 ‰, while successive reconstructions involving Mg/Ca and δ18Oc preclude salinity reconstruction with a precision better than ± 1.69. A new direct linear fit to reconstruct salinity could be established.
Feng Wang, Dominique Arseneault, Étienne Boucher, Shulong Yu, Steeven Ouellet, Gwenaëlle Chaillou, Ann Delwaide, and Lily Wang
Biogeosciences, 17, 4559–4570, https://doi.org/10.5194/bg-17-4559-2020, https://doi.org/10.5194/bg-17-4559-2020, 2020
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Wood stain is challenging the use of the blue intensity technique for dendroclimatic reconstructions. Using stained subfossil trees from eastern Canadian lakes, we compared chemical destaining approaches with the
delta bluemathematical correction of blue intensity data. Although no chemical treatment was completely efficient, the delta blue method is unaffected by the staining problem and thus is promising for climate reconstructions based on lake subfossil material.
Dulcinea V. Groff, David G. Williams, and Jacquelyn L. Gill
Biogeosciences, 17, 4545–4557, https://doi.org/10.5194/bg-17-4545-2020, https://doi.org/10.5194/bg-17-4545-2020, 2020
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Tussock grasses that grow along coastlines of the Falkland Islands are slow to decay and build up thick peat layers over thousands of years. Grass fragments found in ancient peat can be used to reconstruct past climate because grasses can preserve a record of growing conditions in their leaves. We found that modern living tussock grasses in the Falkland Islands reliably record temperature and humidity in their leaves, and the peat they form can be used to understand past climate change.
Maxence Guillermic, Sambuddha Misra, Robert Eagle, Alexandra Villa, Fengming Chang, and Aradhna Tripati
Biogeosciences, 17, 3487–3510, https://doi.org/10.5194/bg-17-3487-2020, https://doi.org/10.5194/bg-17-3487-2020, 2020
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Boron isotope ratios (δ11B) of foraminifera are a promising proxy for seawater pH and can be used to constrain pCO2. In this study, we derived calibrations for new foraminiferal taxa which extend the application of the boron isotope proxy. We discuss the origin of different δ11B signatures in species and also discuss the potential of using multispecies δ11B analyses to constrain vertical pH and pCO2 gradients in ancient water columns to shed light on biogeochemical carbon cycling in the past.
Zeynep Erdem, Joachim Schönfeld, Anthony E. Rathburn, Maria-Elena Pérez, Jorge Cardich, and Nicolaas Glock
Biogeosciences, 17, 3165–3182, https://doi.org/10.5194/bg-17-3165-2020, https://doi.org/10.5194/bg-17-3165-2020, 2020
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Recent observations from today’s oceans revealed that oxygen concentrations are decreasing, and oxygen minimum zones are expanding together with current climate change. With the aim of understanding past climatic events and their relationship with oxygen content, we looked at the fossils, called benthic foraminifera, preserved in the sediment archives from the Peruvian margin and quantified the bottom-water oxygen content for the last 22 000 years.
Hannah K. Donald, Gavin L. Foster, Nico Fröhberg, George E. A. Swann, Alex J. Poulton, C. Mark Moore, and Matthew P. Humphreys
Biogeosciences, 17, 2825–2837, https://doi.org/10.5194/bg-17-2825-2020, https://doi.org/10.5194/bg-17-2825-2020, 2020
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The boron isotope pH proxy is increasingly being used to reconstruct ocean pH in the past. Here we detail a novel analytical methodology for measuring the boron isotopic composition (δ11B) of diatom opal and apply this to the study of the diatom Thalassiosira weissflogii grown in culture over a range of pH. To our knowledge this is the first study of its kind and provides unique insights into the way in which diatoms incorporate boron and their potential as archives of palaeoclimate records.
Eleonora Fossile, Maria Pia Nardelli, Arbia Jouini, Bruno Lansard, Antonio Pusceddu, Davide Moccia, Elisabeth Michel, Olivier Péron, Hélène Howa, and Meryem Mojtahid
Biogeosciences, 17, 1933–1953, https://doi.org/10.5194/bg-17-1933-2020, https://doi.org/10.5194/bg-17-1933-2020, 2020
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This study focuses on benthic foraminiferal distribution in an Arctic fjord characterised by continuous sea ice production during winter and the consequent cascading of salty and corrosive waters (brine) to the seabed. The inner fjord is dominated by calcareous species (C). In the central deep basins, where brines are persistent, calcareous foraminifera are dissolved and agglutinated (A) dominate. The high A/C ratio is suggested as a proxy for brine persistence and sea ice production.
Johannes Hepp, Imke Kathrin Schäfer, Verena Lanny, Jörg Franke, Marcel Bliedtner, Kazimierz Rozanski, Bruno Glaser, Michael Zech, Timothy Ian Eglinton, and Roland Zech
Biogeosciences, 17, 741–756, https://doi.org/10.5194/bg-17-741-2020, https://doi.org/10.5194/bg-17-741-2020, 2020
Julian Struck, Marcel Bliedtner, Paul Strobel, Jens Schumacher, Enkhtuya Bazarradnaa, and Roland Zech
Biogeosciences, 17, 567–580, https://doi.org/10.5194/bg-17-567-2020, https://doi.org/10.5194/bg-17-567-2020, 2020
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We present leaf wax n-alkanes and their compound-specific (CS) δ13C isotopes from semi-arid and/or arid Mongolia to test their potential for paleoenvironmental reconstructions. Plants and topsoils were analysed and checked for climatic control. Chain-length variations are distinct between grasses and Caragana, which are not biased by climate. However CS δ13C is strongly correlated to climate, so n-alkanes and their CS δ13C show great potential for paleoenvironmental reconstruction in Mongolia.
Elena Lo Giudice Cappelli, Jessica Louise Clarke, Craig Smeaton, Keith Davidson, and William Edward Newns Austin
Biogeosciences, 16, 4183–4199, https://doi.org/10.5194/bg-16-4183-2019, https://doi.org/10.5194/bg-16-4183-2019, 2019
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Fjords are known sinks of organic carbon (OC); however, little is known about the long-term fate of the OC stored in these sediments. The reason for this knowledge gap is the post-depositional degradation of OC. This study uses benthic foraminifera (microorganisms with calcite shells) to discriminate between post-depositional OC degradation and actual OC burial and accumulation in fjordic sediments, as foraminifera would only preserve the latter information in their assemblage composition.
Sara K. E. Goulden, Naohiko Ohkouchi, Katherine H. Freeman, Yoshito Chikaraishi, Nanako O. Ogawa, Hisami Suga, Oliver Chadwick, and Benjamin Z. Houlton
Biogeosciences, 16, 3869–3882, https://doi.org/10.5194/bg-16-3869-2019, https://doi.org/10.5194/bg-16-3869-2019, 2019
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We investigate whether soil organic compounds preserve information about nitrogen availability to plants. We isolate chlorophyll degradation products in leaves, litter, and soil and explore possible species and climate effects on preservation and interpretation. We find that compound-specific nitrogen isotope measurements in soil have potential as a new tool to reconstruct changes in nitrogen cycling on a landscape over time, avoiding issues that have limited other proxies.
Nicolai Schleinkofer, Jacek Raddatz, André Freiwald, David Evans, Lydia Beuck, Andres Rüggeberg, and Volker Liebetrau
Biogeosciences, 16, 3565–3582, https://doi.org/10.5194/bg-16-3565-2019, https://doi.org/10.5194/bg-16-3565-2019, 2019
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In this study we tried to correlate Na / Ca ratios from cold-water corals with environmental parameters such as salinity, temperature and pH. We do not observe a correlation between Na / Ca ratios and seawater salinity, but we do observe a strong correlation with temperature. Na / Ca data from warm-water corals (Porites spp.) and bivalves (Mytilus edulis) support this correlation, indicating that similar controls on the incorporation of sodium exist in these aragonitic organisms.
Mattia Greco, Lukas Jonkers, Kerstin Kretschmer, Jelle Bijma, and Michal Kucera
Biogeosciences, 16, 3425–3437, https://doi.org/10.5194/bg-16-3425-2019, https://doi.org/10.5194/bg-16-3425-2019, 2019
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To be able to interpret the paleoecological signal contained in N. pachyderma's shells, its habitat depth must be known. Our investigation on 104 density profiles of this species from the Arctic and North Atlantic shows that specimens reside closer to the surface when sea-ice and/or surface chlorophyll concentrations are high. This is in contrast with previous investigations that pointed at the position of the deep chlorophyll maximum as the main driver of N. pachyderma vertical distribution.
Anna Mikis, Katharine R. Hendry, Jennifer Pike, Daniela N. Schmidt, Kirsty M. Edgar, Victoria Peck, Frank J. C. Peeters, Melanie J. Leng, Michael P. Meredith, Chloe L. C. Jones, Sharon Stammerjohn, and Hugh Ducklow
Biogeosciences, 16, 3267–3282, https://doi.org/10.5194/bg-16-3267-2019, https://doi.org/10.5194/bg-16-3267-2019, 2019
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Antarctic marine calcifying organisms are threatened by regional climate change and ocean acidification. Future projections of regional carbonate production are challenging due to the lack of historical data combined with complex climate variability. We present a 6-year record of flux, morphology and geochemistry of an Antarctic planktonic foraminifera, which shows that their growth is most sensitive to sea ice dynamics and is linked with the El Niño–Southern Oscillation.
Eunmi Park, Jens Hefter, Gerhard Fischer, Morten Hvitfeldt Iversen, Simon Ramondenc, Eva-Maria Nöthig, and Gesine Mollenhauer
Biogeosciences, 16, 2247–2268, https://doi.org/10.5194/bg-16-2247-2019, https://doi.org/10.5194/bg-16-2247-2019, 2019
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We analyzed GDGT-based proxy temperatures in the polar oceans. In the eastern Fram Strait (79° N), the nutrient distribution may determine the depth habit of Thaumarchaeota and thus the proxy temperature. In the Antarctic Polar Front (50° S), the contribution of Euryarchaeota or the nonlinear correlation between the proxy values and temperatures may cause the warm biases of the proxy temperatures relative to SSTs.
Marijke W. de Bar, Jenny E. Ullgren, Robert C. Thunnell, Stuart G. Wakeham, Geert-Jan A. Brummer, Jan-Berend W. Stuut, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 16, 1705–1727, https://doi.org/10.5194/bg-16-1705-2019, https://doi.org/10.5194/bg-16-1705-2019, 2019
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We analyzed sediment traps from the Cariaco Basin, the tropical Atlantic and the Mozambique Channel to evaluate seasonal imprints in the concentrations and fluxes of long-chain diols (LDIs), in addition to the long-chain diol index proxy (sea surface temperature proxy) and the diol index (upwelling indicator). Despite significant degradation, LDI-derived temperatures were very similar for the sediment traps and seafloor sediments, and corresponded to annual mean sea surface temperatures.
Jens Zinke, Juan P. D'Olivo, Christoph J. Gey, Malcolm T. McCulloch, J. Henrich Bruggemann, Janice M. Lough, and Mireille M. M. Guillaume
Biogeosciences, 16, 695–712, https://doi.org/10.5194/bg-16-695-2019, https://doi.org/10.5194/bg-16-695-2019, 2019
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Here we report seasonally resolved sea surface temperature (SST) reconstructions for the southern Mozambique Channel in the SW Indian Ocean, a region located along the thermohaline ocean surface circulation route, based on multi-trace-element temperature proxy records preserved in two Porites sp. coral cores for the past 42 years. Particularly, we show the suitability of both separate and combined Sr / Ca and Li / Mg proxies for improved multielement SST reconstructions.
Hilde Pracht, Brett Metcalfe, and Frank J. C. Peeters
Biogeosciences, 16, 643–661, https://doi.org/10.5194/bg-16-643-2019, https://doi.org/10.5194/bg-16-643-2019, 2019
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In palaeoceanography the shells of single-celled foraminifera are routinely used as proxies to reconstruct the temperature, salinity and circulation of the ocean in the past. Traditionally a number of specimens were pooled for a single stable isotope measurement; however, technical advances now mean that a single shell or chamber of a shell can be measured individually. Three different hypotheses regarding foraminiferal biology and ecology were tested using this approach.
Anna Jentzen, Dirk Nürnberg, Ed C. Hathorne, and Joachim Schönfeld
Biogeosciences, 15, 7077–7095, https://doi.org/10.5194/bg-15-7077-2018, https://doi.org/10.5194/bg-15-7077-2018, 2018
Shauna Ní Fhlaithearta, Christophe Fontanier, Frans Jorissen, Aurélia Mouret, Adriana Dueñas-Bohórquez, Pierre Anschutz, Mattias B. Fricker, Detlef Günther, Gert J. de Lange, and Gert-Jan Reichart
Biogeosciences, 15, 6315–6328, https://doi.org/10.5194/bg-15-6315-2018, https://doi.org/10.5194/bg-15-6315-2018, 2018
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This study looks at how foraminifera interact with their geochemical environment in the seabed. We focus on the incorporation of the trace metal manganese (Mn), with the aim of developing a tool to reconstruct past pore water profiles. Manganese concentrations in foraminifera are investigated relative to their ecological preferences and geochemical environment. This study demonstrates that Mn in foraminiferal tests is a promising tool to reconstruct oxygen conditions in the seabed.
Siobhan Williams, Walter Adey, Jochen Halfar, Andreas Kronz, Patrick Gagnon, David Bélanger, and Merinda Nash
Biogeosciences, 15, 5745–5759, https://doi.org/10.5194/bg-15-5745-2018, https://doi.org/10.5194/bg-15-5745-2018, 2018
Robert Frei, Cora Paulukat, Sylvie Bruggmann, and Robert M. Klaebe
Biogeosciences, 15, 4905–4922, https://doi.org/10.5194/bg-15-4905-2018, https://doi.org/10.5194/bg-15-4905-2018, 2018
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The reconstruction of paleo-redox conditions of seawater has the potential to link to climatic changes on land and therefore to contribute to our understanding of past climate change. The redox-sensitive chromium isotope system is applied to marine calcifiers in order to characterize isotope offsets that result from vital processes during calcification processes and which can be eventually used in fossil equivalents to reconstruct past seawater compositions.
Thomas M. DeCarlo, Michael Holcomb, and Malcolm T. McCulloch
Biogeosciences, 15, 2819–2834, https://doi.org/10.5194/bg-15-2819-2018, https://doi.org/10.5194/bg-15-2819-2018, 2018
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Understanding the mechanisms of coral calcification is limited by the isolation of the calcifying environment. The boron systematics (B / Ca and δ11B) of aragonite have recently been developed as a proxy for the carbonate chemistry of the calcifying fluid, but a variety of approaches have been utilized. We assess the available experimental B / Ca partitioning data and present a computer code for deriving calcifying fluid carbonate chemistry from the boron systematics of coral skeletons.
Manuel Bringué, Robert C. Thunell, Vera Pospelova, James L. Pinckney, Oscar E. Romero, and Eric J. Tappa
Biogeosciences, 15, 2325–2348, https://doi.org/10.5194/bg-15-2325-2018, https://doi.org/10.5194/bg-15-2325-2018, 2018
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We document 2.5 yr of dinoflagellate cyst production in the Cariaco Basin using a sediment trap record. Each species' production pattern is interpreted in the context of the physico-chemical (e.g., temperature, nutrients) and biological (other planktonic groups) environment. Most species respond positively to upwelling, but seem to be negatively impacted by an El Niño event with a 1-year lag. This work helps understanding dinoflagellate ecology and interpreting fossil assemblages in sediments.
Gabriella M. Weiss, Eva Y. Pfannerstill, Stefan Schouten, Jaap S. Sinninghe Damsté, and Marcel T. J. van der Meer
Biogeosciences, 14, 5693–5704, https://doi.org/10.5194/bg-14-5693-2017, https://doi.org/10.5194/bg-14-5693-2017, 2017
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Algal-derived compounds allow us to make assumptions about environmental conditions in the past. In order to better understand how organisms record environmental conditions, we grew microscopic marine algae at different light intensities, salinities, and alkalinities in a temperature-controlled environment. We determined how these environmental parameters affected specific algal-derived compounds, especially their relative deuterium content, which seems to be mainly affected by salinity.
Cited articles
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Barker, P. A., Hurrell, E. R., Leng, M. J., Wolff, C., Cocquyt, C., Sloane, H. J., and Verschuren, D.: Seasonality in equatorial climate over the past 25 k.y. revealed by oxygen isotope records from Kilimanjaro, Geology, 39, 1111–1114, https://doi.org/10.1130/G32419.1, 2011. a
Barker, P. A., Hurrell, E. R., Leng, M. J., Plessen, B., Wolff, C., Conley, D. J., Keppens, E., Milne, I., Cumming, B. F., Laird, K. R., Kendrick, C. P., Wynn, P. M., and Verschuren, D.: Carbon cycling within an East African lake revealed by the carbon isotope composition of diatom silica: A 25 ka record from Lake Challa, Mt. Kilimanjaro, Quaternary Sci. Rev., 66, 55–63, https://doi.org/10.1016/j.quascirev.2012.07.016, 2013. a
Barker, S., Knorr, G., Edwards, R. L., Parrenin, F., Putnam, A. E., Skinner, L. C., Wolff, E., and Ziegler, M.: 800 000 Years of abrupt climate variability, Science, 334, 347–351, https://doi.org/10.1126/science.1203580, 2011. a
Baxter, A. J., Hopmans, E. C., Russell, J. M., and Sinninghe Damsté, J. S.: Bacterial GMGTs in East African lake sediments: Their potential as palaeotemperature indicators, Geochim. Cosmochim. Ac., 259, 155–169, https://doi.org/10.1016/j.gca.2019.05.039, 2019. a
Baxter, A. J., van Bree, L., Peterse, F., Hopmans, E. C., Villanueva, L., Verschuren, D., and Sinninghe Damsté, J. S.: Seasonal and multi-annual variation in the abundance of isoprenoid GDGT membrane lipids and their producers in the water column of a meromictic equatorial crater lake (Lake Chala, East Africa), Quaternary Sci. Rev., 273, 107263, https://doi.org/10.1016/j.quascirev.2021.107263, 2021. a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z, aa, ab, ac, ad, ae, af, ag, ah, ai, aj, ak, al, am
Baxter, A. J., Verschuren, D., Peterse, F., Miralles, D. G., Martin-Jones, C. M., Maitituerdi, A., Van der Meeren, T., Van Daele, M., Lane, C. S., Haug, G. H., Olago, D. O., and Sinninghe Damsté, J. S.: Reversed Holocene temperature–moisture relationship in the Horn of Africa, Nature, 620, 336–343, https://doi.org/10.1038/s41586-023-06272-5, 2023. a, b, c, d, e, f, g, h, i, j, k, l
Baxter, A., Peterse, F., Verschuren, D., and Sinninghe Damsté, J.: Iso- and brGDGT peak areas and concentrations from the DeepCHALLA sediment sequence (Lake Chala, Kenya/Tanzania), Zenodo [data set], https://doi.org/10.5281/zenodo.11068099, 2024. a
Bechtel, A., Smittenberg, R. H., Bernasconi, S. M., and Schubert, C. J.: Distribution of branched and isoprenoid tetraether lipids in an oligotrophic and a eutrophic Swiss lake: Insights into sources and GDGT-based proxies, Org. Geochem., 41, 822–832, https://doi.org/10.1016/j.orggeochem.2010.04.022, 2010. a
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Short summary
This study investigates the impact of long-term lake-system evolution on the climate signal recorded by glycerol dialkyl glycerol tetraethers (GDGTs), a popular biomarker in paleoclimate research. It compares downcore changes in GDGTs in the 250 000 year sediment sequence of Lake Chala (Kenya/Tanzania) to independent data for lake mixing and water-column chemistry. These factors influence the GDGT proxies in the earliest depositional phases (before ~180 ka), confounding the climate signal.
This study investigates the impact of long-term lake-system evolution on the climate signal...
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