Articles | Volume 7, issue 11
https://doi.org/10.5194/bg-7-3901-2010
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-7-3901-2010
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
30 Nov 2010
Diagenetic control of nitrogen isotope ratios in Holocene sapropels and recent sediments from the Eastern Mediterranean Sea
J. Möbius
Institute of Biogeochemistry and Marine Chemistry, University of Hamburg, Bundesstr. 55, 20146 Hamburg, Germany
N. Lahajnar
Institute of Biogeochemistry and Marine Chemistry, University of Hamburg, Bundesstr. 55, 20146 Hamburg, Germany
K.-C. Emeis
Institute of Biogeochemistry and Marine Chemistry, University of Hamburg, Bundesstr. 55, 20146 Hamburg, Germany
Related subject area
Paleobiogeoscience: Proxy use, Development & Validation
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
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
Deep-sea stylasterid δ18O and δ13C maps inform sampling scheme for paleotemperature reconstructions
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
Interplay of community dynamics, temperature, and productivity on the hydrogen isotope signatures of lipid biomarkers
Benthic foraminiferal Mn / Ca ratios reflect microhabitat preferences
The effects of environment on Arctica islandica shell formation and architecture
Diatoms as a paleoproductivity proxy in the NW Iberian coastal upwelling system (NE Atlantic)
Factors controlling the depth habitat of planktonic foraminifera in the subtropical eastern North Atlantic
The effect of shell secretion rate on Mg / Ca and Sr / Ca ratios in biogenic calcite as observed in a belemnite rostrum
Allix J. Baxter, Francien Peterse, Dirk Verschuren, Aihemaiti Maitituerdi, Nicolas Waldmann, and Jaap S. Sinninghe Damsté
Biogeosciences, 21, 2877–2908, https://doi.org/10.5194/bg-21-2877-2024, https://doi.org/10.5194/bg-21-2877-2024, 2024
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Theresa M. King and Brad E. Rosenheim
Biogeosciences Discuss., https://doi.org/10.5194/bg-2022-180, https://doi.org/10.5194/bg-2022-180, 2022
Revised manuscript accepted for BG
Short summary
Short summary
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 coral skeleton for accurate temperature reconstructions.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
S. Nemiah Ladd, Nathalie Dubois, and Carsten J. Schubert
Biogeosciences, 14, 3979–3994, https://doi.org/10.5194/bg-14-3979-2017, https://doi.org/10.5194/bg-14-3979-2017, 2017
Short summary
Short summary
Hydrogen isotopes of lipids provide valuable information about microbial activity, climate, and environmental stress. We show that heavy hydrogen in fatty acids declines from spring to summer in a nutrient-rich and a nutrient-poor lake and that the effect is nearly 3 times as big in the former. This effect is likely a combination of increased biomass from algae, warmer temperatures, and higher algal growth rates.
Karoliina A. Koho, Lennart J. de Nooijer, Christophe Fontanier, Takashi Toyofuku, Kazumasa Oguri, Hiroshi Kitazato, and Gert-Jan Reichart
Biogeosciences, 14, 3067–3082, https://doi.org/10.5194/bg-14-3067-2017, https://doi.org/10.5194/bg-14-3067-2017, 2017
Short summary
Short summary
Here we report Mn / Ca ratios in living benthic foraminifera from the NE Japan margin. The results show that the Mn incorporation directly reflects the environment where the foraminifera calcify. Foraminifera that live deeper in sediment, under greater redox stress, generally incorporate more Mn into their carbonate skeletons. As such, foraminifera living close to the Mn reduction zone in sediment appear promising tools for paleoceanographic reconstructions of sedimentary redox conditions.
Stefania Milano, Gernot Nehrke, Alan D. Wanamaker Jr., Irene Ballesta-Artero, Thomas Brey, and Bernd R. Schöne
Biogeosciences, 14, 1577–1591, https://doi.org/10.5194/bg-14-1577-2017, https://doi.org/10.5194/bg-14-1577-2017, 2017
Diana Zúñiga, Celia Santos, María Froján, Emilia Salgueiro, Marta M. Rufino, Francisco De la Granda, Francisco G. Figueiras, Carmen G. Castro, and Fátima Abrantes
Biogeosciences, 14, 1165–1179, https://doi.org/10.5194/bg-14-1165-2017, https://doi.org/10.5194/bg-14-1165-2017, 2017
Short summary
Short summary
Diatoms are one of the most important primary producers in highly productive coastal regions. Their silicified valves are susceptible to escape from the upper water column and be preserved in the sediment record, and thus are frequently used to reconstruct environmental conditions in the past from sediment cores. Here, we assess how water column diatom’s community in the NW Iberian coastal upwelling system is seasonally transferred from the surface to the seafloor sediments.
Andreia Rebotim, Antje H. L. Voelker, Lukas Jonkers, Joanna J. Waniek, Helge Meggers, Ralf Schiebel, Igaratza Fraile, Michael Schulz, and Michal Kucera
Biogeosciences, 14, 827–859, https://doi.org/10.5194/bg-14-827-2017, https://doi.org/10.5194/bg-14-827-2017, 2017
Short summary
Short summary
Planktonic foraminifera species depth habitat remains poorly constrained and the existing conceptual models are not sufficiently tested by observational data. Here we present a synthesis of living planktonic foraminifera abundance data in the subtropical eastern North Atlantic from vertical plankton tows. We also test potential environmental factors influencing the species depth habitat and investigate yearly or lunar migration cycles. These findings may impact paleoceanographic studies.
Clemens Vinzenz Ullmann and Philip A. E. Pogge von Strandmann
Biogeosciences, 14, 89–97, https://doi.org/10.5194/bg-14-89-2017, https://doi.org/10.5194/bg-14-89-2017, 2017
Short summary
Short summary
This study documents how much control growth rate has on the chemical composition of fossil shell material. Using a series of chemical analyses of the fossil hard part of a belemnite, an extinct marine predator, a clear connection between the rate of calcite formation and its magnesium and strontium contents was found. These findings provide further insight into biomineralization processes and help better understand chemical signatures of fossils as proxies for palaeoenvironmental conditions.
Cited articles
Altabet, M. A.: Variations in nitrogen isotopic composition between sinking and suspended particles: implications for nitrogen cycling and particle transformation in the open ocean, Deep-Sea Res. Pt. I, 35, 535–554, 1988.
Altabet, M. A.: Nitrogen and carbon isotopic tracers of the source and transformation of particles in the deep-sea, in: Particle Flux in the Ocean, edited by: Ittekkot, V., Schafer, P., Honjo, S., and Depetris, P. J., Wiley London, 155–184, 1996.
Altabet, M. A.: Constraints on oceanic N balance/imbalance from sedimentary 15N records, Biogeosciences, 4, 75–86, https://doi.org/10.5194/bg-4-75-2007, 2007.
Altabet, M. A. and Francois, R.: Sedimentary Nitrogen Isotopic Ratio as a Recorder for Surface Ocean Nitrate Utilization, Global Biogeochem. Cy., 8, 103–116, 1994.
Anastasakis, G. C. and Stanley, D. J.: Sapropels and organic-rich variants in the Mediterranean: sequence development and classification, in: Fine-grained Sediments: Deep-water Processes and Facies, edited by: Stow, D. A. W. and Piper, D. J. W., Geological Society London, 497–510, 1984.
Anastasakis, G. C. and Stanley, D. J.: Uppermost Sapropel, Eastern Mediterranean – Paleoceanography and Stagnation, Natl. Geogr. Res., 2, 179–197, 1986.
Arnaboldi, M. and Meyers, P. A.: Patterns of organic carbon and nitrogen isotopic compositions of latest Pliocene sapropels from six locations across the Mediterranean Sea, Palaeogeogr. Palaeocl., 235, 149–167, 2006.
Bada, J. L., Schoeninger, M. J., and Schimmelmann, A.: Isotopic Fractionation During Peptide-Bond Hydrolysis, Geochim. Cosmochim. Ac., 53, 3337–3341, 1989.
Bethoux, J. P.: Oxygen-Consumption, New Production, Vertical Advection and Environmental Evolution in the Mediterranean-Sea, Deep-Sea Res. Pt. I, 36, 769–781, 1989.
Bishop, J. K. B.: The barite-opal-organic carbon association in oceanic particulate matter, Nature, 332, 341–343, 1988.
Calvert, S. E., Nielsen, B., and Fontugne, M. R.: Evidence from nitrogen isotope ratios for enhanced productivity during formation of Eastern Mediterranean sapropels, Nature, 359, 223–225, 1992.
Cheddadi, R. and Rossignol-Strick, M.: Eastern Mediterranean Quaternary Paleoclimates from Pollen and Isotope Records of Marine Cores in the Nile Cone Area, Paleoceanography, 10, 291–300, 1995.
Coban-Yildiz, Y., Altabet, M. A., Yilmaz, A., and Tugrul, S.: Carbon and nitrogen isotopic ratios of suspended particulate organic matter (SPOM) in the Black Sea water column, Deep-Sea Res. Pt. II, 53, 1875–1892, 2006.
Dähnke, K., Serna, A., Blanz, T., and Emeis, K. C.: Sub-recent nitrogen-isotope trends in sediments from Skagerrak (North sea) and Kattegat: Changes in N-budgets and N-sources?, Mar. Geol., 253, 92–98, 2008.
Dauwe, B., Middelburg, J. J., Herman, P. M. J., and Heip, C. H. R.: Linking diagenetic alteration of aminoacids and bulk organic matter reactivity, Limnol. Oceanogr., 44, 1809–1814, 1999.
De Lange, G. J., Thomson, J., Reitz, A., Slomp, C. P., Principato, M. S., Erba, E., and Corselli, C.: Synchronous basin-wide formation and redox-controlled preservation of a Mediterranean sapropel, Nat. Geosci., 1, 606–610, https://doi.org/10.1038/ngeo283, 2008.
Dehairs, F., Chesselet, R., and Jedwab, J.: Discrete suspended particles of barite and the barium cycle in the open ocean, Earth Planet. Sc. Lett., 49, 528–550, 1980.
Dehairs, F., Goeyens, L., Stroobants, N., Bernard, P., Goyet, C., Poisson, A., and Chesselet, R.: On Suspended Barite and the Oxygen Minimum in the Southern Ocean, Global Biogeochem. Cy., 40, 85–102, 1990.
Dymond, J., Suess, E., and Lyle, M.: Barium in deep-sea sediments: A geochemical proxy for paleoproductivity, Paleoceanography, 7, 163–181, 1992.
Emeis, K. C. and Weissert, H.: Tethyan-Mediterranean organic carbon-rich sediments from Mesozoic black shales to sapropels, Sedimentology, 56, 247–266, 2009.
Emeis, K.-C., Robertson, A. H. F., and Richter, C. (Eds.): Proceedings of the Ocean Drilling Program, Initial Reports 160, Ocean Drilling Program, College Station, TX, 972 pp., 1996.
Emeis, K.-C., Struck, U., Schulz, H.-M., Rosenberg, R., Bernasconi, S., Erlenkeuser, H., Sakamoto, T., and Martinez-Ruiz, F.: Temperature and salinity variations of Mediterranean Sea surface waters over the last 16 000 years from records of planktonic stable oxygen isotopes and alkenone unsaturation ratios, Palaeogeogr. Palaeocl., 158, 259–280, 2000.
Farrell, G., Pedersen, T. F., Calvert, S. E., and Nielsen, B.: Glacial-interglacial changes in nutrient utilization in the equatorial Pacific Ocean, Nature, 377, 514–517, 1995.
Francois, R., Honjo, S., Manganini, S. J., and Ravizza, G. E.: Biogenic Barium Fluxes to the Deep-Sea – Implications for Paleoproductivity Reconstruction, Global Biogeochem. Cy., 9, 289–303, 1995.
Freudenthal, T., Wagner, T., Wenzhöfer, F., Zabel, M., and Wefer, G.: Early diagenesis of organic matter from sediments of the eastern subtropical Atlantic: evidence from stable nitrogen and carbon isotopes, Geochim. Cosmochim. Ac., 65, 1795–1808, 2001.
Fry, B.: Stable Isotope Ecology, Springer-Verlag, Berlin, 308 pp., 2007.
Fry, B., Jannasch, H. W., Molyneaux, S. J., Wirsen, C. O., Muramoto, J. A., and King, S.: Stable Isotope Studies of the Carbon, Nitrogen and Sulfur Cycles in the Black-Sea and the Cariaco Trench, Deep-Sea Res. Pt. I, 38, 1003–1019, 1991.
Fuchsman, C. A., Murray, J. W., and Konovalov, S. K.: Concentration and natural stable isotope profiles of nitrogen species in the Black Sea, Mar. Chem., 111, 90–105, 2008.
Ganeshram, R. S., Pedersen, T. F., Calvert, S. E., and Francois, R.: Reduced nitrogen fixation in the glacial ocean inferred from changes in marine nitrogen and phosphorus inventories, Nature, 415, 156–159, 2002.
Garvin, J., Buick, R., Anbar, A. D., Arnold, G. L., and Kaufman, A. J.: Isotopic Evidence for an Aerobic Nitrogen Cycle in the Latest Archean, Science, 323, 1045–1048, 2009.
Gaye-Haake, B., Lahajnar, N., Emeis, K. C., Unger, D., Rixen, T., Suthhof, A., Ramaswamy, V., Schulz, H., Paropkari, A. L., Guptha, M. V. S., and Ittekkot, V.: Stable nitrogen isotopic ratios of sinking particles and sediments from the northern Indian Ocean, Mar. Chem., 96, 243–255, 2005.
Giunta, S., Negri, A., Morigi, C., Capotondi, L., Combourieu-Nebout, N., Emeis, K. C., Sangiorgi, F., and Vigliotti, L.: Coccolithophorid ecostratigraphy and multi-proxy paleoceanographic reconstruction in the Southern Adriatic Sea during the last deglacial time (Core AD91-17), Palaeogeogr. Palaeocl., 190, 39–59, 2003.
Higgins, M. B., Robinson, R. S., Carter, S. J., and Pearson, A.: Evidence from chlorine isotopes for alternating nutrient regimes in the Eastern Mediterranean Sea, Earth Planet. Sc. Lett., 290, 102–107, 2010.
Hoch, M. P., Fogel, M. L., and Kirchman, D. L.: Isotope Fractionation Associated with Ammonium Uptake by a Marine Bacterium, Limnol. Oceanogr., 37, 1447–1459, 1992.
Holmes, M. E., Muller, P. J., Schneider, R. R., Segl, M., Patzold, J., and Wefer, G.: Stable nitrogen isotopes in Angola Basin surface sediments, Mar. Geol., 134, 1–12, 1996.
Holmes, M. E., Müller, P. J., Segl, M., and Wefer, G.: Reconstruction of past nutrient utilization in the eastern Angola Basin based on sedimentary 15N/14N ratios, Paleoceanography, 12(4), 604–614, 1997.
Howell, M. W. and Thunell, R. C.: Organic carbon accumulation in Bannock Basin: Evaluating the role of productivity in the formation of eastern Mediterranean sapropels, Mar. Geol., 103, 461–471, 1992.
Jenkyns, H. C., Grocke, D. R., and Hesselbo, S. P.: Nitrogen isotope evidence for water mass denitrification during the early Toarcian (Jurassic) oceanic anoxic event, Paleoceanography, 16, 593–603, 2001.
Jennerjahn, T. C. and Ittekkot, V.: Changes in organic matter from surface waters to continental slope sediments off the Sao Francisco River, eastern Brazil, Mar. Geol., 161, 129–140, 1999.
Jung, M., Ilmberger, J., Mangini, A., and Emeis, K. C.: Why some Mediterranean sapropels survived burn-down (and others did not), Mar. Geol., 141, 51–60, 1997.
Kemp, A. E. S., Pearce, R. B., Koizumi, I., Pike, J., and Rance, S. J.: The role of mat-forming diatoms in the formation of Mediterranean sapropels, Nature, 398, 57–61, 1999.
Krom, M. D., Woodward, E. M. S., Herut, B., Kress, N., Carbo, P., Mantoura, R. F. C., Spyres, G., Thingstad, T. F., Wassmann, P., Wexels-Riser, C., Kitidis, V., Law, C. S., and Zodiatis, G.: Nutrient cycling in the south east Levantine basin of the eastern Mediterranean: Results from a phosphorus starved system, Deep-Sea Res. Pt. II, 52, 2879–2896, 2005.
Krom, M. D., Emeis, K. C., and Van Cappellen, P.: Why is the Eastern Mediterranean phosphorus limited?, Progr. Oceanogr., 85, 236–244, 2010.
Kuhnt, T., Schmiedl, G., Ehrmann, W., Hamann, Y., and Hemleben, C.: Deep-sea ecosystem variability of the Aegean Sea during the past 22 kyr as revealed by Benthic Foraminifera, Mar. Micropaleontol., 64, 141–162, 2007.
Kuypers, M. M. M., van Breugel, Y., Schouten, S., Erba, E., and Damste, J. S. S.: N-2-fixing cyanobacteria supplied nutrient N for Cretaceous oceanic anoxic events, Geology, 32, 853–856, 2004.
Lahajnar, N., Wiesner, M. G., and Gaye, B.: Fluxes of amino acids and hexosamines to the deep South China Sea, Deep-Sea Res. Pt. I, 54, 2120–2144, 2007.
Lehmann, M. F., Bernasconi, S. M., Barbieri, A., and McKenzie, J. A.: Preservation of organic matter and alteration of its carbon and nitrogen isotope composition during simulated and in situ early sedimentary diagenesis, Geochim. Cosmochim. Ac., 66, 3573–3584, 2002.
Macko, S. A. and Estep, M. L. F.: Microbial alteration of stable nitrogen and carbon isotopic compositions of organic matter, Org. Geochem., 6, 787–790, 1984.
Mara, P., Mihalopoulos, N., Gogou, A., Daehnke, K., Schlarbaum, T., Emeis, K. C., and Krom, M.: Isotopic composition of nitrate in wet and dry atmospheric deposition on Crete in the eastern Mediterranean Sea, Global Biogeochem. Cy., 23, GB4002, https://doi.org/10.1029/2008gb003395, 2009.
Mayer, B., Boyer, E. W., Goodale, C., Jaworski, N. A., Van Breemen, N., Howarth, R. W., Seitzinger, S., Billen, G., Lajtha, L. J., Nosal, M., and Paustian, K.: Sources of nitrate in rivers draining sixteen watersheds in the northeastern US: Isotopic constraints, Biogeochemistry, 57, 171–197, 2002.
McCarthy, J. J., Yilmaz, A., Coban-Yildiz, Y., and Nevins, J. L.: Nitrogen cycling in the offshore waters of the Black Sea, Estuar. Coast. Shelf S., 74, 493–514, 2007.
McClelland, J. W. and Valiela, I.: Linking nitrogen in estuarine producers to land-derived sources, Limnol. Oceanogr., 43, 577–585, 1998.
McCoy, F. W.: Late Quaternary sedimentation in the eastern Mediterranean Sea, Harvard University, 1974.
Mercone, D., Thomson, J., Abu-Zied, R. H., Croudace, I. W., and Rohling, E. J.: High-resolution geochemical and micropalaeontological profiling of the most recent eastern Mediterranean sapropel, Mar. Geol., 177, 25–44, 2001.
Meyers, P. A. and Bernasconi, S. M.: Carbon and nitrogen isotope excursions in mid-Pleistocene sapropels from the Tyrrhenian Basin: Evidence for climate-induced increases in microbial primary production, Mar. Geol., 220, 41–58, 2005.
Milder, J. C. and Montoya, J. P.: Carbon and nitrogen stable isotope ratios at Sites 969 and 974: interpreting spatial gradients in sapropel properties, in: Proc. ODP, Scientific Results, edited by: Zahn, R., Comas, M., and Klaus, A., Ocean Drilling Programm College Station, 161, 401–411, 1999.
Minagawa, M. and Wada, E.: Nitrogen Isotope Ratios of Red Tide Organisms in the East-China-Sea – a Characterization of Biological Nitrogen-Fixation, Mar. Chem., 19, 245–259, 1986.
Moodley, L., Middleburg, J. J., Herman, P. M. J., Soetaert, K., and de Lange, G. J.: Oxygenation and organic-matter preservation in marine sediments: Direct experimental evidence from ancient organic carbon-rich deposits, Geology, 33, 889–892, 2005.
Murat, A. and Got, H.: Organic carbon variations of the eastern Mediterranean Holocene sapropel: a key for understanding formation processes, Palaeogeogr. Palaeocl., 158, 241–257, 2000.
Pantoja, S., Repeta, D. J., Sachs, J. P., and Sigman, D. M.: Stable isotope constraints on the nitrogen cycle of the Mediterranean Sea water column, Deep-Sea Res. Pt. I, 49, 1609–1621, 2002.
Ren, H., Sigman, D., Meckler, A. N., Plessen, B., Robinson, R. S., Rosenthal, Y., and Haug, G. H.: Foraminiferal Isotope Evidence of Reduced Nitrogen Fixation in the Ice Age Atlantic Ocean, Science, 323, 244–248, 2009.
Reschke, S.: Biogeochemie der Schwebstofffracht der Donau und deren Einflu{ß} auf das Sedimentationsgeschehen im nordwestlichen Schwarzen Meer, Ph.D thesis, Universität Hamburg, Hamburg, 109 pp., 1999.
Rohling, E. J.: Review and new aspects concerning the formation of eastern Mediterranean sapropels, Mar. Geol., 122, 1–28, 1994.
Rohling, E. J., Hopmans, E. C., and Damste, J. S. S.: Water column dynamics during the last interglacial anoxic event in the Mediterranean (sapropel S5), Paleoceanography, 21, PA2018, https://doi.org/10.1029/2005Pa001237, 2006.
Rossignolstrick, M., Nesteroff, W., Olive, P., and Vergnaudgrazzini, C.: After the Deluge – Mediterranean Stagnation and Sapropel Formation, Nature, 295, 105–110, 1982.
Ryan, W. B. F.: Stratigraphy of Late Quarternary sediments in the eastern Mediterranean, in: The Mediterranean Sea: a Natural Sedimentation Laboratory, edited by: Stanley, D. J., Dowden, Hutchinson and Ross, Stroudsburg, Pa, 149–169, 1972.
Sachs, J. P. and Repeta, D. J.: Oligotrophy and Nitrogen Fixation During Eastern Mediterranean Sapropel Events, Science, 286, 2485–2488, 1999.
Saino, T. and Hattori, A.: N-15 Natural Abundance in Oceanic Suspended Particulate Matter, Nature, 283, 752–754, 1980.
Sigman, D. M., Altabet, M. A., Francois, R., McCorkle, D. C., and Gaillard, J. F.: The isotopic composition of diatom-bound nitrogen in Southern Ocean sediments, Paleoceanography, 14, 118–134, 1999.
Silfer, J. A., Engel, M. H., and Macko, S. A.: Kinetic Fractionation of Stable Carbon and Nitrogen Isotopes During Peptide-Bond Hydrolysis – Experimental-Evidence and Geochemical Implications, Chem. Geol., 101, 211–221, 1992.
Slomp, C. P., Thomson, J., and de Lange, G. J.: Enhanced regeneration of phosphorus during formation of the most recent eastern Mediterranean sapropel (S1), Geochim. Cosmochim. Ac., 66, 1171–1184, 2002.
Struck, U., Emeis, K.-C., Voss, M., Krom, M. D., and Rau, G. H.: Biological productivity during sapropel S5 formation in the Eastern Mediterranean Sea: evidence from stable isotopes of nitrogen and carbon, Geochim. Cosmochim. Ac., 65, 3249–3266, 2001.
Thomson, J., Higgs, N. C., Wilson, T. R. S., Croudace, I. W., De Lange, G. J., and Van Santvoort, P. J. M.: Redistribution and geochemical behaviour of redox-sensitive elements around S1, the most recent eastern Mediterranean sapropel, Geochim. Cosmochim. Ac., 59, 3487–3501, 1995.
Thomson, J., Mercone, D., De Lange, G. J., and Van Santvoort, P. J. M.: Review of recent advances in the interpretation of eastern Mediterranean sapropel S1 from geochemical evidence, Mar. Geol., 153, 77–89, 1999.
Triantaphyllou, M. V., Antonarakou, A., Kouli, K., Dimiza, M., Kontakiotis, G., Papanikolaou, M. D., Ziveri, P., Mortyn, P. G., Lianou, V., Lykousis, V., and Dermitzakis, M. D.: Late Glacial-Holocene ecostratigraphy of the south-eastern Aegean Sea, based on plankton and pollen assemblages, Geo-Mar. Lett., 29, 249–267, https://doi.org/10.1007/s00367-009-0139-5, 2009.
Tyrrell, T.: The relative influences of nitrogen and phosphorus on oceanic primary production, Nature, 400, 525–531, 1999.
Voss, M., Nausch, G., and Montoya, J. P.: Nitrogen stable isotope dynamics in the central Baltic Sea: influence of deep-water renewal on the N-cycle changes, Mar. Ecol.-Prog. Ser., 158, 11–21, 1997.
Voss, M., Emeis, K. C., Hille, S., Neumann, T. and Dippner, J. W.: Nitrogen cycle of the Baltic Sea from an isotopic perspective, Global Biogeochem. Cy., 19, GB3001, https://doi.org/10.1029/2004GB002338, 2005.
Voss, M., Deutsch, B., Elmgren, R., Humborg, C., Kuuppo, P., Pastuszak, M., Rolff, C., and Schulte, U.: Source identification of nitrate by means of isotopic tracers in the Baltic Sea catchments, Biogeosciences, 3, 663–676, https://doi.org/10.5194/bg-3-663-2006, 2006.
Wallmann, K.: Feedbacks between oceanic redox states and marine productivity: A model perspective focused on benthic phosphorus cycling, Global Biogeochem. Cy., 17, 1084, https://doi.org/10.1029/2002GB001968, 2003.
Westley, M. B., Yamagishi, H., Popp, B. N., and Yoshida, N.: Nitrous oxide cycling in the Black Sea inferred from stable isotope and isotopomer distributions, Deep-Sea Res. Pt. II, 53, 1802–1816, 2006.
Altmetrics
Final-revised paper
Preprint