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Antolín F, Jacomet S, Soteras R, Gerling C, Bernasconi SM, Follmann F, Hajdas I, Jaggi M, Jesus A, Martínez-Grau H, Oms FX, Röder B, Steiner BL, van Willigen S. An archaeobotanical and stable isotope approach to changing agricultural practices in the NW Mediterranean region around 4000 BC. Holocene 2024; 34:239-254. [PMID: 38259723 PMCID: PMC10799764 DOI: 10.1177/09596836231211848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 09/01/2023] [Indexed: 01/24/2024]
Abstract
It has recently been observed, that a change in the crop spectrum happened during the so-called Middle Neolithic in France at ca. 4000 BC. An agricultural system based on free-threshing cereals (naked wheat and naked barley) seems to shift to one based on glume wheats. This is a major change for traditional farmers and this paper aims to shed light on its possible causes. Here we describe the results of new investigations in a key area for the understanding of this process: the NW Mediterranean arch, where free-threshing cereals are the main cultivars since ca. 5100 BC. New data confirm that the shift towards glume wheats is also observed in some sites of the NE of the Iberian Peninsula and that among the glume wheats that spread at ca. 4000 BC we should not only consider emmer and einkorn but also Timopheevi's wheat. Stable isotope analyses indicate no major decrease in soil fertility or alterations in local precipitation regimes. The agricultural change may be the result of a combination of the spread of damaging pests for free-threshing cereals and presumably new networks being developed with the North-eastern part of Italy and the Balkans.
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Affiliation(s)
- Ferran Antolín
- German Archaeological Institute, Natural Sciences Unit, Germany
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), Basel University, Switzerland
| | - Stefanie Jacomet
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), Basel University, Switzerland
| | - Raül Soteras
- German Archaeological Institute, Natural Sciences Unit, Germany
| | - Claudia Gerling
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), Basel University, Switzerland
- Departement Altertumswissenschaften, Ur- und Frühgeschichtliche und Provinzialrömische Archäologie, Basel University, Switzerland
| | | | - Franziska Follmann
- German Archaeological Institute, Natural Sciences Unit, Germany
- Institut für Prähistorische Archäologie, Freie Universität Berlin, Germany
| | - Irka Hajdas
- Laboratory of Ion Beam Physics (LIP), Swiss Federal Institute of Technology (ETH) Zurich, Switzerland
| | - Madalina Jaggi
- Department of Earth Sciences, Geological Institute, ETH Zurich, Switzerland
| | - Ana Jesus
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), Basel University, Switzerland
| | - Héctor Martínez-Grau
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), Basel University, Switzerland
| | - Francesc Xavier Oms
- Seminari d’Estudis i Recerques Prehistòriques (SERP). Secció de Prehistòria i Arqueologia, Dept. d’Història i Arqueologia, Facultat de Geografia i Història. Universitat de Barcelona, Spain
- Institut d’Arqueologia de la Universitat de Barcelona. Facultat de Geografia i Història. Universitat de Barcelona, Spain
| | - Brigitte Röder
- Departement Altertumswissenschaften, Ur- und Frühgeschichtliche und Provinzialrömische Archäologie, Basel University, Switzerland
| | - Bigna L Steiner
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), Basel University, Switzerland
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2
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Weber UW, Rinaldi AP, Roques C, Wenning QC, Bernasconi SM, Brennwald MS, Jaggi M, Nussbaum C, Schefer S, Mazzotti M, Wiemer S, Giardini D, Zappone A, Kipfer R. In-situ experiment reveals CO 2 enriched fluid migration in faulted caprock. Sci Rep 2023; 13:17006. [PMID: 37813929 PMCID: PMC10562487 DOI: 10.1038/s41598-023-43231-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 09/21/2023] [Indexed: 10/11/2023] Open
Abstract
The sealing characteristics of the geological formation located above a CO2 storage reservoir, the so-called caprock, are essential to ensure efficient geological carbon storage. If CO2 were to leak through the caprock, temporal changes in fluid geochemistry can reveal fundamental information on migration mechanisms and induced fluid-rock interactions. Here, we present the results from a unique in-situ injection experiment, where CO2-enriched fluid was continuously injected in a faulted caprock analogue. Our results show that the CO2 migration follows complex pathways within the fault structure. The joint analysis of noble gases, ion concentrations and carbon isotopes allow us to quantify mixing between injected CO2-enriched fluid and resident formation water and to describe the temporal evolution of water-rock interaction processes. The results presented here are a crucial complement to the geophysical monitoring at the fracture scale highlighting a unique migration of CO2 in fault zones.
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Affiliation(s)
| | | | - Clément Roques
- Department of Earth Sciences, ETH Zürich, Zürich, Switzerland
- Centre for Hydrogeology and Geothermics, University of Neuchâtel, Neuchâtel, Switzerland
| | - Quinn C Wenning
- Department of Earth Sciences, ETH Zürich, Zürich, Switzerland
| | | | - Matthias S Brennwald
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Madalina Jaggi
- Department of Earth Sciences, ETH Zürich, Zürich, Switzerland
| | | | | | - Marco Mazzotti
- Institute of Energy and Process Engineering, ETH Zürich, Zürich, Switzerland
| | - Stefan Wiemer
- Swiss Seismological Service, ETH Zürich, Zürich, Switzerland
| | | | - Alba Zappone
- Swiss Seismological Service, ETH Zürich, Zürich, Switzerland.
- Institute of Energy and Process Engineering, ETH Zürich, Zürich, Switzerland.
| | - Rolf Kipfer
- Department of Earth Sciences, ETH Zürich, Zürich, Switzerland
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
- Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland
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3
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Wolf A, Ersek V, Braun T, French AD, McGee D, Bernasconi SM, Skiba V, Griffiths ML, Johnson KR, Fohlmeister J, Breitenbach SFM, Pausata FSR, Tabor CR, Longman J, Roberts WHG, Chandan D, Peltier WR, Salzmann U, Limbert D, Trinh HQ, Trinh AD. Deciphering local and regional hydroclimate resolves contradicting evidence on the Asian monsoon evolution. Nat Commun 2023; 14:5697. [PMID: 37709741 PMCID: PMC10502020 DOI: 10.1038/s41467-023-41373-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 09/01/2023] [Indexed: 09/16/2023] Open
Abstract
The winter and summer monsoons in Southeast Asia are important but highly variable sources of rainfall. Current understanding of the winter monsoon is limited by conflicting proxy observations, resulting from the decoupling of regional atmospheric circulation patterns and local rainfall dynamics. These signals are difficult to decipher in paleoclimate reconstructions. Here, we present a winter monsoon speleothem record from Southeast Asia covering the Holocene and find that winter and summer rainfall changed synchronously, forced by changes in the Pacific and Indian Oceans. In contrast, regional atmospheric circulation shows an inverse relation between winter and summer controlled by seasonal insolation over the Northern Hemisphere. We show that disentangling the local and regional signal in paleoclimate reconstructions is crucial in understanding and projecting winter and summer monsoon variability in Southeast Asia.
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Affiliation(s)
- Annabel Wolf
- Department of Earth System Science, University of California, Irvine, CA, 92697, USA.
- Department of Geography and Environmental Sciences, Northumbria University Newcastle, Newcastle-upon-Tyne, NE1 8ST, UK.
| | - Vasile Ersek
- Department of Geography and Environmental Sciences, Northumbria University Newcastle, Newcastle-upon-Tyne, NE1 8ST, UK.
| | - Tobias Braun
- Potsdam Institute for Climate Impact Research, 14473, Potsdam, Germany
| | - Amanda D French
- Environmental Research Institute, Waikato University, Hamilton, 3240, New Zealand
| | - David McGee
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139-4307, USA
| | | | - Vanessa Skiba
- Potsdam Institute for Climate Impact Research, 14473, Potsdam, Germany
| | - Michael L Griffiths
- Department of Environmental Science, William Paterson University, Wayne, NJ, 07470, USA
| | - Kathleen R Johnson
- Department of Earth System Science, University of California, Irvine, CA, 92697, USA
| | - Jens Fohlmeister
- Federal Office for Radiations Protection, 10318, Berlin, Germany
| | - Sebastian F M Breitenbach
- Department of Geography and Environmental Sciences, Northumbria University Newcastle, Newcastle-upon-Tyne, NE1 8ST, UK
| | - Francesco S R Pausata
- Department of Earth and Atmospheric Sciences, Centre ESCER (Étude et la Simulation du Climat à l'Échelle Régionale) and GEOTOP (Research Center on the dynamics of the Earth System), University of Quebec in Montreal, Montréal, QC, Canada
| | - Clay R Tabor
- Department of Earth Sciences, University of Connecticut, Storrs, CT, 06269, USA
| | - Jack Longman
- Department of Geography and Environmental Sciences, Northumbria University Newcastle, Newcastle-upon-Tyne, NE1 8ST, UK
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, 26129, Germany
| | - William H G Roberts
- Department of Geography and Environmental Sciences, Northumbria University Newcastle, Newcastle-upon-Tyne, NE1 8ST, UK
| | - Deepak Chandan
- Department of Physics, University of Toronto, 60 St. George Street, Toronto, ON, M5S1A7, Canada
| | - W Richard Peltier
- Department of Physics, University of Toronto, 60 St. George Street, Toronto, ON, M5S1A7, Canada
| | - Ulrich Salzmann
- Department of Geography and Environmental Sciences, Northumbria University Newcastle, Newcastle-upon-Tyne, NE1 8ST, UK
| | | | - Hong Quan Trinh
- Institute of Chemistry, Vietnam Academy of Science and Technology, Ha Noi, 10072, Viet Nam
| | - Anh Duc Trinh
- Nuclear Training Center, Vietnam Atomic Energy Institute, 140 Nguyen Tuan, Thanh Xuan, Ha Noi, 11416, Viet Nam
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4
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Steiner BL, Martínez-Grau H, Bernasconi SM, Gross E, Hajdas I, Jacomet S, Jaggi M, Schaeren GF, Antolín F. Archaeobotanical and isotopic analyses of waterlogged remains from the Neolithic pile-dwelling site of Zug-Riedmatt (Switzerland): Resilience strategies of a plant economy in a changing local environment. PLoS One 2022; 17:e0274361. [PMID: 36170265 PMCID: PMC9518907 DOI: 10.1371/journal.pone.0274361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 08/25/2022] [Indexed: 11/19/2022] Open
Abstract
The excellent preservation of the waterlogged botanical remains of the multiphase Neolithic pile-dwelling site of Zug-Riedmatt (Central Switzerland) yielded an ideal dataset to delve into the issue of plant economy of a community spanning several decades. The study identified a major change in crops where oil plants played a key role in the site’s initial phase before being supplanted over the course of a few decades by naked wheat, barley and pea. Wild plants continued to be gathered albeit in different proportions. In the latest settlement phase, the changes in the local vegetation and in the values of the analyses of carbon stable isotopes suggest a less humid environment. The hypothesis is that the changes perceived in the plant economy represent a resilience strategy adopted by the inhabitants in reaction to short term local climatic alterations. The two types of soil sampling techniques (monolith and bulk) allowed comparing these results. While the density of plant remains appears to be underestimated among the samples collected by the monolith technique, the proportions of economic taxa remain unaffected. The findings thus reveal that when the bulk samplings are distributed carefully throughout multiphase sites and avoid mixing stratigraphical units, and if the samplings are representative of all archaeological features from a whole area, then each of the two techniques offer analogous results.
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Affiliation(s)
- Bigna L. Steiner
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), University of Basel, Basel, Switzerland
- * E-mail:
| | - Héctor Martínez-Grau
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), University of Basel, Basel, Switzerland
| | | | - Eda Gross
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), University of Basel, Basel, Switzerland
| | - Irka Hajdas
- Laboratory of Ion Beam Physics, ETH Zurich, Zürich, Switzerland
| | - Stefanie Jacomet
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), University of Basel, Basel, Switzerland
| | | | | | - Ferran Antolín
- Department of Environmental Sciences, Integrative Prehistory and Archaeological Science (IPAS), University of Basel, Basel, Switzerland
- German Archaeological Institute, Berlin, Germany
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5
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Deng L, Meile C, Fiskal A, Bölsterli D, Han X, Gajendra N, Dubois N, Bernasconi SM, Lever MA. Deposit-feeding worms control subsurface ecosystem functioning in intertidal sediment with strong physical forcing. PNAS Nexus 2022; 1:pgac146. [PMID: 36714871 PMCID: PMC9802194 DOI: 10.1093/pnasnexus/pgac146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 07/25/2022] [Indexed: 06/18/2023]
Abstract
Intertidal sands are global hotspots of terrestrial and marine carbon cycling with strong hydrodynamic forcing by waves and tides and high macrofaunal activity. Yet, the relative importance of hydrodynamics and macrofauna in controlling these ecosystems remains unclear. Here, we compare geochemical gradients and bacterial, archaeal, and eukaryotic gene sequences in intertidal sands dominated by subsurface deposit-feeding worms (Abarenicola pacifica) to adjacent worm-free areas. We show that hydrodynamic forcing controls organismal assemblages in surface sediments, while in deeper layers selective feeding by worms on fine, algae-rich particles strongly decreases the abundance and richness of all three domains. In these deeper layers, bacterial and eukaryotic network connectivity decreases, while percentages of clades involved in degradation of refractory organic matter, oxidative nitrogen, and sulfur cycling increase. Our findings reveal macrofaunal activity as the key driver of biological community structure and functioning, that in turn influence carbon cycling in intertidal sands below the mainly physically controlled surface layer.
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Affiliation(s)
| | - Christof Meile
- Department of Marine Sciences, University of Georgia, 325 Sanford Drive, Athens, GA 30602, USA
| | | | - Damian Bölsterli
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Universitätstrasse 16, 8092 Zurich, Switzerland
| | | | - Niroshan Gajendra
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Universitätstrasse 16, 8092 Zurich, Switzerland
| | - Nathalie Dubois
- Department of Surface Waters - Research and Management, Swiss Federal Institute of Aquatic Science and Technology (EAWAG), Überlandstrasse 133, 8600 Dübendorf, Switzerland
- Department of Earth Sciences, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Sonneggstrasse 5, 8092 Zürich, Switzerland
| | - Stefano M Bernasconi
- Department of Earth Sciences, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Sonneggstrasse 5, 8092 Zürich, Switzerland
| | - Mark A Lever
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Universitätstrasse 16, 8092 Zurich, Switzerland
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6
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Kantnerová K, Barthel M, Six J, Emmenegger L, Bernasconi SM, Mohn J. Stable Isotope Analysis of Greenhouse Gases Requires Analyte Preconcentration. Chimia (Aarau) 2022. [DOI: 10.2533/chimia.2022.656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Nitrous oxide (N2O) is an important trace gas contributing to global warming and depletion of ozone in the stratosphere. Its increasing abundance is caused mainly by anthropogenic sources, such as application of fertilizers in agriculture or emissions from industry. To understand the N2O global budget, its sources and sinks need to be well-described and quantified. In this project, a new method for N2O source appointment was developed that can help with this task. The method is based on analysis of the eight most abundant isotopic molecules of N2O, using quantum cascade laser absorption spectroscopy (QCLAS). The applicability of the method towards the N2O biogeochemical cycle was demonstrated on a prominent N2O source (bacterial denitrification) and the most important N2O sink (UV photolysis) on samples prepared in laboratory experiments. An extension of the QCLAS method to natural samples can be achieved by hyphenation with a preconcentration technique that increases concentration of the analyte and standardizes the sample matrix. This article provides an overview of currently applied preconcentration techniques in the field of greenhouse-gas analysis and a description of the preconcentration device TREX that will be employed in future projects with the developed QCLAS method.
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7
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Meckler AN, Sexton PF, Piasecki AM, Leutert TJ, Marquardt J, Ziegler M, Agterhuis T, Lourens LJ, Rae JWB, Barnet J, Tripati A, Bernasconi SM. Cenozoic evolution of deep ocean temperature from clumped isotope thermometry. Science 2022; 377:86-90. [PMID: 35771913 DOI: 10.1126/science.abk0604] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Characterizing past climate states is crucial for understanding the future consequences of ongoing greenhouse gas emissions. Here, we revisit the benchmark time series for deep ocean temperature across the past 65 million years using clumped isotope thermometry. Our temperature estimates from the deep Atlantic Ocean are overall much warmer compared with oxygen isotope-based reconstructions, highlighting the likely influence of changes in deep ocean pH and/or seawater oxygen isotope composition on classical oxygen isotope records of the Cenozoic. In addition, our data reveal previously unrecognized large swings in deep ocean temperature during early Eocene acute greenhouse warmth. Our results call for a reassessment of the Cenozoic history of ocean temperatures to achieve a more accurate understanding of the nature of climatic responses to tectonic events and variable greenhouse forcing.
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Affiliation(s)
- A N Meckler
- Bjerknes Centre for Climate Research and Department of Earth Science, University of Bergen, Bergen, Norway
| | - P F Sexton
- School of Environment, Earth and Ecosystem Sciences, The Open University, Milton Keynes, UK
| | - A M Piasecki
- Bjerknes Centre for Climate Research and Department of Earth Science, University of Bergen, Bergen, Norway
| | - T J Leutert
- Bjerknes Centre for Climate Research and Department of Earth Science, University of Bergen, Bergen, Norway
| | - J Marquardt
- Bjerknes Centre for Climate Research and Department of Earth Science, University of Bergen, Bergen, Norway
| | - M Ziegler
- Faculty of Geosciences, Utrecht University, Utrecht, Netherlands
| | - T Agterhuis
- Faculty of Geosciences, Utrecht University, Utrecht, Netherlands
| | - L J Lourens
- Faculty of Geosciences, Utrecht University, Utrecht, Netherlands
| | - J W B Rae
- School of Earth and Environmental Sciences, University of St. Andrews, St. Andrews, UK
| | - J Barnet
- School of Earth and Environmental Sciences, University of St. Andrews, St. Andrews, UK
| | - A Tripati
- Department of Earth, Planetary, and Space Science, Department of Atmospheric and Oceanic Science, Institute of the Environment and Sustainability, American Indian Studies Center, Center for Diverse Leadership in Science, University of California, Los Angeles, Los Angeles, USA
| | - S M Bernasconi
- Department of Earth Science, ETH Zürich, Zürich, Switzerland
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8
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Saintilan NJ, Archer C, Maden C, Samankassou E, Bernasconi SM, Szumigala D, Mahaffey Z, West A, Spangenberg JE. Metal-rich organic matter and hot continental passive margin: drivers for Devonian copper-cobalt-germanium mineralization in dolomitized reef-bearing carbonate platform. Miner Depos 2022; 58:37-49. [PMID: 36644759 PMCID: PMC9829613 DOI: 10.1007/s00126-022-01123-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 04/26/2022] [Indexed: 06/17/2023]
Abstract
UNLABELLED The abundance and types of reef-bearing carbonate platforms reflect the evolution of Devonian climate, with conspicuous microbial-algal reefs in the warm Early and Late Devonian and sponge-coral reefs in the cooler Middle Devonian. A dolomitized Wenlock-Lower Devonian microbial-algal reef-bearing carbonate platform hosts epigenetic copper-cobalt-germanium (Cu-Co-Ge) sulfide mineralization at Ruby Creek-Bornite in the Brooks Range, Alaska. Here, we present rhenium-osmium (Re-Os) radiometric ages and molybdenum and sulfur (δ98/95Mo = +2.04 to +5.48‰ and δ34S = -28.5 to -1.8‰) isotope variations for individual Cu-Co-Fe sulfide phases along the paragenetic sequence carrollite-bornite-pyrite. In the context of a hot, extensional passive margin, greenhouse conditions in the Early Devonian favored restriction of platform-top seawater circulation and episodic reflux of oxidized brines during growth of the carbonaceous carbonate platform. Molybdenum and sulfur isotope data signal the stepwise reduction of hot brines carrying Cu during latent reflux and geothermal circulation for at least ca. 15 million years from the Early Devonian until Cu-Co sulfide mineralization ca. 379-378 million years ago (Ma) in the Frasnian, Late Devonian (weighted mean of Re-Os model ages of carrollite at 379 ± 15 Ma [n = 4]; Re-Os isochron age of bornite at 378 ± 15 Ma [n = 6]). On the basis of petrographic relationships between sulfides and solid bitumen, and the Mo and S isotope data for sulfides, we imply that the endowment in critical metals (e.g., Co, Ge, Re) in the Ruby Creek-Bornite deposit is linked to the activity of primary producers that removed trace metals from the warm Early Devonian seawater and concentrated Co, Ge, and Re in algal-bacterial organic matter in carbonate sediments. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s00126-022-01123-1.
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Affiliation(s)
- Nicolas J. Saintilan
- Institute of Geochemistry and Petrology, ETH Zürich, Clausiusstrasse 25, 8092 Zurich, Switzerland
| | - Corey Archer
- Institute of Geochemistry and Petrology, ETH Zürich, Clausiusstrasse 25, 8092 Zurich, Switzerland
| | - Colin Maden
- Institute of Geochemistry and Petrology, ETH Zürich, Clausiusstrasse 25, 8092 Zurich, Switzerland
| | - Elias Samankassou
- Department of Earth Sciences, Rue des Maraîchers 13, 1205 Geneva, Switzerland
| | | | - David Szumigala
- Ambler Metals LLC, 3700 Centerpoint Drive, Ste. #101, Anchorage, AK USA
| | - Zach Mahaffey
- Ambler Metals LLC, 3700 Centerpoint Drive, Ste. #101, Anchorage, AK USA
| | - Andy West
- Ambler Metals LLC, 3700 Centerpoint Drive, Ste. #101, Anchorage, AK USA
| | - Jorge E. Spangenberg
- Institute of Earth Surface Dynamics, University of Lausanne, Building Geopolis, 1015 Lausanne, Switzerland
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9
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Ternieten L, Früh‐Green GL, Bernasconi SM. Carbon Geochemistry of the Active Serpentinization Site at the Wadi Tayin Massif: Insights From the ICDP Oman Drilling Project: Phase II. J Geophys Res Solid Earth 2021; 126:e2021JB022712. [PMID: 35859726 PMCID: PMC9285459 DOI: 10.1029/2021jb022712] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 11/08/2021] [Accepted: 11/26/2021] [Indexed: 06/15/2023]
Abstract
A large part of the hydrated oceanic lithosphere consists of serpentinites exposed in ophiolites. Serpentinites constitute reactive chemical and thermal systems and potentially represent an effective sink for CO2. Understanding carbonation mechanisms within ophiolites are almost exclusively based on studies of outcrops, which can limit the interpretation of fossil hydrothermal systems. We present stable and radiogenic carbon isotope data that provide insights into the isotopic trends and fluid evolution of peridotite carbonation in ICDP Oman Drilling Project drill holes BA1B (400-m deep) and BA3A (300-m deep). Geochemical investigations of the carbonates in serpentinites indicate formation in the last 50 kyr, implying a distinctly different phase of alteration than the initial oceanic hydration and serpentinization of the Samail Ophiolite. The oldest carbonates (∼31 to >50 kyr) are localized calcite, dolomite, and aragonite veins, formed between 26°C and 43°C and related to focused fluid flow. Subsequent pervasive small amounts of dispersed carbonate precipitated in the last 1,000 years. Macroscopic brecciation and veining of the peridotite indicate that carbonation is influenced by tectonic features allowing infiltration of fluids over extended periods and at different structural levels such as along fracture planes and micro-fractures and grain boundaries, causing large-scale hydration of the ophiolite. The formation of dispersed carbonate is related to percolating fluids with δ 18O lower than modern ground and meteoric water. Our study shows that radiocarbon investigations are an essential tool to interpret the carbonation history and that stable oxygen and carbon isotopes alone can result in ambiguous interpretations.
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10
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de Oliveira Mascarenhas R, Sena-Souza JP, Bernasconi SM, McKenzie JA, Vasconcelos C, Muniz TR, Nogueira E Silva MP, da Silva Salvador FA, Rumbelsperger AMB. Building an isoscape based on tooth enamel for human provenance estimation in Brazil. Forensic Sci Int 2021; 330:111109. [PMID: 34839156 DOI: 10.1016/j.forsciint.2021.111109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 11/12/2021] [Accepted: 11/15/2021] [Indexed: 11/26/2022]
Abstract
In this study, we present a correlation between δ18OC values of carbonate in tooth enamel samples from the modern Brazilian population and the available δ18ODW data for the meteoric water from the Global Network of Isotopes in Precipitation (GNIP). Tooth enamel from 119 Brazilian individuals from five different regions of the country were analyzed. The δ18OC isoscape obtained is in good agreement with the isoscape based on regional meteoric and drinking water. The regression matrix obtained for the δ18O values of the carbonate tooth enamel and meteoric water was used to build an isoscape using the regression-kriging approach. Our data show that Brazil can be divided in two main regions with respect to the δ18O values of the carbonate tooth enamel: (1) the most easterly part of the northeast region, which is characterized by a warm and dry climate and (2) the remainder of the country, stretching from the Amazon rain forest to the more southernly regions. The data herein reported can be used for forensic purposes related to human identification.
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Affiliation(s)
- Ricardo de Oliveira Mascarenhas
- Brazilian Federal Police, Technical-Scientific Section, R. Profa. Sandália Monzon 210, 82640-040, Curitiba, PR, Brazil; Laboratory of Mineral and Rock Analysis (LAMIR), Department of Geology, Federal University of Paraná, PO Box 19062, 81531-980 Curitiba, PR, Brazil.
| | - João Paulo Sena-Souza
- Department of Geosciences, State University of Montes Claros (Unimontes), Campus Universitário Prof. Darcy Ribeiro, Av. Prof. Rui Braga, s/n - Vila Mauriceia, 39401-089 Montes Claros, MG, Brazil
| | - Stefano M Bernasconi
- Department of Earth Sciences, ETH Zürich, Sonneggstr. 5, 8092 Zürich, Switzerland
| | - Judith A McKenzie
- Department of Earth Sciences, ETH Zürich, Sonneggstr. 5, 8092 Zürich, Switzerland
| | - Crisógono Vasconcelos
- Center for Technological Development (CEDES), Geological Survey of Brazil, Av. Pasteur 404, 22290-240, Rio de Janeiro-RJ, Brazil
| | - Taís Ribeiro Muniz
- Laboratory of Mineral and Rock Analysis (LAMIR), Department of Geology, Federal University of Paraná, PO Box 19062, 81531-980 Curitiba, PR, Brazil
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11
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Vickers ML, Bernasconi SM, Ullmann CV, Lode S, Looser N, Morales LG, Price GD, Wilby PR, Hougård IW, Hesselbo SP, Korte C. Marine temperatures underestimated for past greenhouse climate. Sci Rep 2021; 11:19109. [PMID: 34580353 PMCID: PMC8476565 DOI: 10.1038/s41598-021-98528-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 09/09/2021] [Indexed: 02/08/2023] Open
Abstract
Understanding the Earth's climate system during past periods of high atmospheric CO2 is crucial for forecasting climate change under anthropogenically-elevated CO2. The Mesozoic Era is believed to have coincided with a long-term Greenhouse climate, and many of our temperature reconstructions come from stable isotopes of marine biotic calcite, in particular from belemnites, an extinct group of molluscs with carbonate hard-parts. Yet, temperatures reconstructed from the oxygen isotope composition of belemnites are consistently colder than those derived from other temperature proxies, leading to large uncertainties around Mesozoic sea temperatures. Here we apply clumped isotope palaeothermometry to two distinct carbonate phases from exceptionally well-preserved belemnites in order to constrain their living habitat, and improve temperature reconstructions based on stable oxygen isotopes. We show that belemnites precipitated both aragonite and calcite in warm, open ocean surface waters, and demonstrate how previous low estimates of belemnite calcification temperatures has led to widespread underestimation of Mesozoic sea temperatures by ca. 12 °C, raising estimates of some of the lowest temperature estimates for the Jurassic period to values which approach modern mid-latitude sea surface temperatures. Our findings enable accurate recalculation of global Mesozoic belemnite temperatures, and will thus improve our understanding of Greenhouse climate dynamics.
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Affiliation(s)
- Madeleine L. Vickers
- grid.5254.60000 0001 0674 042XFaculty of Science, Geology Section, University of Copenhagen, Øster Voldgade 10, 1350 Copenhagen K, Denmark
| | - Stefano M. Bernasconi
- grid.5801.c0000 0001 2156 2780Geologisches Institut, Dep. Erdwissenschaften, ETH Zürich, Sonneggstrasse 5, 8092 Zürich, Switzerland
| | - Clemens V. Ullmann
- grid.4991.50000 0004 1936 8948Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN UK ,grid.8391.30000 0004 1936 8024Camborne School of Mines, University of Exeter, Penryn Campus, Penryn, TR10 9FE Cornwall UK
| | - Stefanie Lode
- grid.13508.3f0000 0001 1017 5662Department of Petrology and Economic Geology, Geological Survey of Denmark and Greenland, Øster Voldgade 10, 1350 Copenhagen K, Denmark
| | - Nathan Looser
- grid.5801.c0000 0001 2156 2780Geologisches Institut, Dep. Erdwissenschaften, ETH Zürich, Sonneggstrasse 5, 8092 Zürich, Switzerland
| | - Luiz Grafulha Morales
- grid.5801.c0000 0001 2156 2780Geologisches Institut, Dep. Erdwissenschaften, ETH Zürich, Sonneggstrasse 5, 8092 Zürich, Switzerland ,grid.5801.c0000 0001 2156 2780Scientific Centre for Optical and Electron Microscopy (ScopeM), ETH Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
| | - Gregory D. Price
- grid.11201.330000 0001 2219 0747School of Geography, Earth and Environmental Sciences, Plymouth University, Drake Circus, Plymouth, PL4 8AA UK
| | - Philip R. Wilby
- grid.474329.f0000 0001 1956 5915British Geological Survey, Keyworth, Nottingham, NG12 5GG UK ,grid.9918.90000 0004 1936 8411School of Geography, Geology and the Environment, University of Leicester, University Road, Leicester, LE1 7RH UK
| | - Iben Winther Hougård
- grid.5254.60000 0001 0674 042XFaculty of Science, Geology Section, University of Copenhagen, Øster Voldgade 10, 1350 Copenhagen K, Denmark
| | - Stephen P. Hesselbo
- grid.8391.30000 0004 1936 8024Camborne School of Mines, University of Exeter, Penryn Campus, Penryn, TR10 9FE Cornwall UK
| | - Christoph Korte
- grid.5254.60000 0001 0674 042XFaculty of Science, Geology Section, University of Copenhagen, Øster Voldgade 10, 1350 Copenhagen K, Denmark
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12
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Cerling TE, Bernasconi SM, Hofstetter LS, Jaggi M, Wyss F, Rudolf von Rohr C, Clauss M. CH4/CO2 Ratios and Carbon Isotope Enrichment Between Diet and Breath in Herbivorous Mammals. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.638568] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Breath and diet samples were collected from 29 taxa of animals at the Zurich and Basel Zoos to characterize the carbon isotope enrichment between breath and diet. Diet samples were measured for δ13C and breath samples for CH4/CO2 ratios and for the respired component of δ13C using the Keeling plot approach. Different digestive physiologies included coprophagous and non-coprophagous hindgut fermenters, and non-ruminant and ruminant foregut fermenters. Isotope enrichments from diet to breath were 0.8 ± 0.9‰, 3.5 ± 0.8‰, 2.3 ± 0.4‰, and 4.1 ± 1.0‰, respectively. CH4/CO2 ratios were strongly correlated with isotope enrichments for both hindgut and foregut digestive strategies, although CH4 production was not the sole reason for isotope enrichment. Average CH4/CO2 ratios per taxon ranged over several orders of magnitude from 10–5 to 10–1. The isotope enrichment values for diet-breath can be used to further estimate the isotope enrichment from diet-enamel because Passey et al. (2005b) found a nearly constant isotope enrichment for breath-enamel for diverse mammalian taxa. The understanding of isotope enrichment factors from diet to breath and diet to enamel will have important applications in the field of animal physiology, and possibly also for wildlife ecology and paleontology.
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13
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Vickers ML, Lengger SK, Bernasconi SM, Thibault N, Schultz BP, Fernandez A, Ullmann CV, McCormack P, Bjerrum CJ, Rasmussen JA, Hougård IW, Korte C. Cold spells in the Nordic Seas during the early Eocene Greenhouse. Nat Commun 2020; 11:4713. [PMID: 32948769 PMCID: PMC7501286 DOI: 10.1038/s41467-020-18558-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 08/21/2020] [Indexed: 11/18/2022] Open
Abstract
The early Eocene (c. 56 - 48 million years ago) experienced some of the highest global temperatures in Earth’s history since the Mesozoic, with no polar ice. Reports of contradictory ice-rafted erratics and cold water glendonites in the higher latitudes have been largely dismissed due to ambiguity of the significance of these purported cold-climate indicators. Here we apply clumped isotope paleothermometry to a traditionally qualitative abiotic proxy, glendonite calcite, to generate quantitative temperature estimates for northern mid-latitude bottom waters. Our data show that the glendonites of the Danish Basin formed in waters below 5 °C, at water depths of <300 m. Such near-freezing temperatures have not previously been reconstructed from proxy data for anywhere on the early Eocene Earth, and these data therefore suggest that regionalised cool episodes punctuated the background warmth of the early Eocene, likely linked to eruptive phases of the North Atlantic Igneous Province. The early Eocene was characterized by exceptionally high global temperatures and no polar ice. Here, clumped isotope paleothermometry of glendonite calcite from the Danish Basin shows that these were formed in waters below 5 °C, indicating that regionalised cool episodes punctuated the background warmth of the early Eocene.
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Affiliation(s)
- Madeleine L Vickers
- IGN, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen, Denmark.
| | - Sabine K Lengger
- Biogeochemistry Research Centre, School of Geography, Earth and Environmental Sciences, Plymouth University, Drake Circus, Plymouth, PL4 8AA, UK
| | | | - Nicolas Thibault
- IGN, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen, Denmark
| | | | - Alvaro Fernandez
- Bjerknes Centre for Climate Research and Department of Earth Science, University of Bergen, Allégaten 41, N-5007, Bergen, Norway
| | - Clemens V Ullmann
- Camborne School of Mines, University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE, UK
| | - Paul McCormack
- Biogeochemistry Research Centre, School of Geography, Earth and Environmental Sciences, Plymouth University, Drake Circus, Plymouth, PL4 8AA, UK
| | - Christian J Bjerrum
- IGN, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen, Denmark
| | - Jan Audun Rasmussen
- Museum Mors, Fossil- and Mo-clay Museum, Skarrehagevej 8, 7900, Nykøbing Mors, Denmark
| | | | - Christoph Korte
- IGN, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen, Denmark
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14
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Kantnerová K, Yu L, Zindel D, Zahniser MS, Nelson DD, Tuzson B, Nakagawa M, Toyoda S, Yoshida N, Emmenegger L, Bernasconi SM, Mohn J. First investigation and absolute calibration of clumped isotopes in N 2 O by mid-infrared laser spectroscopy. Rapid Commun Mass Spectrom 2020; 34:e8836. [PMID: 32430945 DOI: 10.1002/rcm.8836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE Unravelling the biogeochemical cycle of the potent greenhouse gas nitrous oxide (N2 O) is an underdetermined problem in environmental sciences due to the multiple source and sink processes involved, which complicate mitigation of its emissions. Measuring the doubly isotopically substituted molecules (isotopocules) of N2 O can add new opportunities to fingerprint and constrain its cycle. METHODS We present a laser spectroscopic technique to selectively and simultaneously measure the eight most abundant isotopocules of N2 O, including three doubly substituted species - so called "clumped isotopes". For the absolute quantification of individual isotopocule abundances, we propose a new calibration scheme that combines thermal equilibration of a working standard gas with a direct mole fraction-based approach. RESULTS The method is validated for a large range of isotopic composition values by comparison with other established methods (laser spectroscopy using conventional isotopic scale and isotope ratio mass spectrometry). Direct intercomparison with recently developed ultrahigh-resolution mass spectrometry shows clearly the advantages of the new laser technique, especially with respect to site specificity of isotopic substitution in the N2 O molecule. CONCLUSIONS Our study represents a new methodological basis for the measurements of both singly substituted and clumped N2 O isotopes. It has a high potential to stimulate future research in the N2 O community by establishing a new class of reservoir-insensitive tracers and molecular-scale insights.
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Affiliation(s)
- Kristýna Kantnerová
- Empa, Laboratory for Air Pollution/Environmental Technology, Dübendorf, 8600, Switzerland
- ETH Zürich, Department of Earth Sciences, Zürich, 8092, Switzerland
| | - Longfei Yu
- Empa, Laboratory for Air Pollution/Environmental Technology, Dübendorf, 8600, Switzerland
| | - Daniel Zindel
- ETH Zurich, Laboratory of Physical Chemistry, Zürich, 8093, Switzerland
| | - Mark S Zahniser
- Aerodyne Research Inc., Center for Atmospheric and Environmental Chemistry, Billerica, MA, 01821, USA
| | - David D Nelson
- Aerodyne Research Inc., Center for Atmospheric and Environmental Chemistry, Billerica, MA, 01821, USA
| | - Béla Tuzson
- Empa, Laboratory for Air Pollution/Environmental Technology, Dübendorf, 8600, Switzerland
| | - Mayuko Nakagawa
- Tokyo Institute of Technology, Earth-Life Science Institute (ELSI), Tokyo, 152-8550, Japan
| | - Sakae Toyoda
- Tokyo Institute of Technology, Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Yokohama, 226-8503, Japan
| | - Naohiro Yoshida
- Tokyo Institute of Technology, Earth-Life Science Institute (ELSI), Tokyo, 152-8550, Japan
- Tokyo Institute of Technology, Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Yokohama, 226-8503, Japan
| | - Lukas Emmenegger
- Empa, Laboratory for Air Pollution/Environmental Technology, Dübendorf, 8600, Switzerland
| | | | - Joachim Mohn
- Empa, Laboratory for Air Pollution/Environmental Technology, Dübendorf, 8600, Switzerland
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15
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Hasenfratz AP, Jaccard SL, Martínez-García A, Sigman DM, Hodell DA, Vance D, Bernasconi SM, Kleiven HKF, Haumann FA, Haug GH. The residence time of Southern Ocean surface waters and the 100,000-year ice age cycle. Science 2019; 363:1080-1084. [PMID: 30846597 DOI: 10.1126/science.aat7067] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 01/23/2019] [Indexed: 11/02/2022]
Abstract
From 1.25 million to 700,000 years ago, the ice age cycle deepened and lengthened from 41,000- to 100,000-year periodicity, a transition that remains unexplained. Using surface- and bottom-dwelling foraminifera from the Antarctic Zone of the Southern Ocean to reconstruct the deep-to-surface supply of water during the ice ages of the past 1.5 million years, we found that a reduction in deep water supply and a concomitant freshening of the surface ocean coincided with the emergence of the high-amplitude 100,000-year glacial cycle. We propose that this slowing of deep-to-surface circulation (i.e., a longer residence time for Antarctic surface waters) prolonged ice ages by allowing the Antarctic halocline to strengthen, which increased the resistance of the Antarctic upper water column to orbitally paced drivers of carbon dioxide release.
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Affiliation(s)
- Adam P Hasenfratz
- Geological Institute, Department of Earth Sciences, ETH Zürich, Zürich, Switzerland. .,Institute of Geological Sciences and Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Samuel L Jaccard
- Institute of Geological Sciences and Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland.
| | | | - Daniel M Sigman
- Department of Geosciences, Guyot Hall, Princeton University, Princeton, NJ, USA
| | - David A Hodell
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
| | - Derek Vance
- Institute of Geochemistry and Petrology, ETH Zürich, Zürich, Switzerland
| | - Stefano M Bernasconi
- Geological Institute, Department of Earth Sciences, ETH Zürich, Zürich, Switzerland
| | - Helga Kikki F Kleiven
- Department of Earth Science, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
| | - F Alexander Haumann
- British Antarctic Survey, Cambridge, UK.,Atmospheric and Oceanic Sciences, Princeton University, Princeton, NJ, USA
| | - Gerald H Haug
- Geological Institute, Department of Earth Sciences, ETH Zürich, Zürich, Switzerland.,Max Planck Institute for Chemistry, Mainz, Germany
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16
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Eickenbusch P, Takai K, Sissman O, Suzuki S, Menzies C, Sakai S, Sansjofre P, Tasumi E, Bernasconi SM, Glombitza C, Jørgensen BB, Morono Y, Lever MA. Origin of Short-Chain Organic Acids in Serpentinite Mud Volcanoes of the Mariana Convergent Margin. Front Microbiol 2019; 10:1729. [PMID: 31404165 PMCID: PMC6677109 DOI: 10.3389/fmicb.2019.01729] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 07/12/2019] [Indexed: 11/17/2022] Open
Abstract
Serpentinitic systems are potential habitats for microbial life due to frequently high concentrations of microbial energy substrates, such as hydrogen (H2), methane (CH4), and short-chain organic acids (SCOAs). Yet, many serpentinitic systems are also physiologically challenging environments due to highly alkaline conditions (pH > 10) and elevated temperatures (>80°C). To elucidate the possibility of microbial life in deep serpentinitic crustal environments, International Ocean Discovery Program (IODP) Expedition 366 drilled into the Yinazao, Fantangisña, and Asùt Tesoru serpentinite mud volcanoes on the Mariana Forearc. These mud volcanoes differ in temperature (80, 150, 250°C, respectively) of the underlying subducting slab, and in the porewater pH (11.0, 11.2, 12.5, respectively) of the serpentinite mud. Increases in formate and acetate concentrations across the three mud volcanoes, which are positively correlated with temperature in the subducting slab and coincide with strong increases in H2 concentrations, indicate a serpentinization-related origin. Thermodynamic calculations suggest that formate is produced by equilibrium reactions with dissolved inorganic carbon (DIC) + H2, and that equilibration continues during fluid ascent at temperatures below 80°C. By contrast, the mechanism(s) of acetate production are not clear. Besides formate, acetate, and H2 data, we present concentrations of other SCOAs, methane, carbon monoxide, and sulfate, δ13C-data on bulk carbon pools, and microbial cell counts. Even though calculations indicate a wide range of microbial catabolic reactions to be thermodynamically favorable, concentration profiles of potential energy substrates, and very low cell numbers suggest that microbial life is scarce or absent. We discuss the potential roles of temperature, pH, pressure, and dispersal in limiting the occurrence of microbial life in deep serpentinitic environments.
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Affiliation(s)
- Philip Eickenbusch
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Zurich, Switzerland
| | - Ken Takai
- SUGAR Program, Institute for Extra-Cutting-Edge Science and Technology Avant-Garde Research (X-star), Japan Agency for Marine-Earth Science Technology, Yokosuka, Japan
| | | | - Shino Suzuki
- Geomicrobiology Research Group, Kochi Institute for Core Sample Research, Japan Agency for Marine-Earth Science and Technology, Kochi, Japan
| | - Catriona Menzies
- Ocean and Earth Science, National Oceanography Centre, University of Southampton, Southampton, United Kingdom.,Department of Geology and Petroleum Geology, University of Aberdeen, Aberdeen, United Kingdom
| | - Sanae Sakai
- SUGAR Program, Institute for Extra-Cutting-Edge Science and Technology Avant-Garde Research (X-star), Japan Agency for Marine-Earth Science Technology, Yokosuka, Japan
| | - Pierre Sansjofre
- Laboratoire Géosciences Océan UMR 6538, Université de Bretagne Occidentale, Brest, France
| | - Eiji Tasumi
- SUGAR Program, Institute for Extra-Cutting-Edge Science and Technology Avant-Garde Research (X-star), Japan Agency for Marine-Earth Science Technology, Yokosuka, Japan
| | | | - Clemens Glombitza
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Zurich, Switzerland.,NASA Ames Research Center, Moffett Field, CA, United States
| | - Bo Barker Jørgensen
- Department of Bioscience, Center for Geomicrobiology, Aarhus University, Aarhus, Denmark
| | - Yuki Morono
- Geomicrobiology Research Group, Kochi Institute for Core Sample Research, Japan Agency for Marine-Earth Science and Technology, Kochi, Japan
| | - Mark Alexander Lever
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Zurich, Switzerland
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17
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Kantnerová K, Tuzson B, Emmenegger L, Bernasconi SM, Mohn J. Quantifying Isotopic Signatures of N2O Using Quantum Cascade Laser Absorption Spectroscopy. Chimia (Aarau) 2019; 73:232-238. [PMID: 30975249 DOI: 10.2533/chimia.2019.232] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Kristýna Kantnerová
- Laboratory for Air Pollution / Environmental Technology, Empa – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | - Béla Tuzson
- Laboratory for Air Pollution / Environmental Technology, Empa – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | - Lukas Emmenegger
- Laboratory for Air Pollution / Environmental Technology, Empa – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | - Stefano M. Bernasconi
- Geological Institute, Department of Earth Sciences, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland
| | - Joachim Mohn
- Laboratory for Air Pollution / Environmental Technology, Empa – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
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18
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Labrado AL, Brunner B, Bernasconi SM, Peckmann J. Formation of Large Native Sulfur Deposits Does Not Require Molecular Oxygen. Front Microbiol 2019; 10:24. [PMID: 30740094 PMCID: PMC6355691 DOI: 10.3389/fmicb.2019.00024] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 01/09/2019] [Indexed: 01/05/2023] Open
Abstract
Large native (i.e., elemental) sulfur deposits can be part of caprock assemblages found on top of or in lateral position to salt diapirs and as stratabound mineralization in gypsum and anhydrite lithologies. Native sulfur is formed when hydrocarbons come in contact with sulfate minerals in presence of liquid water. The prevailing model for native sulfur formation in such settings is that sulfide produced by sulfate-reducing bacteria is oxidized to zero-valent sulfur in presence of molecular oxygen (O2). Although possible, such a scenario is problematic because: (1) exposure to oxygen would drastically decrease growth of microbial sulfate-reducing organisms, thereby slowing down sulfide production; (2) on geologic timescales, excess supply with oxygen would convert sulfide into sulfate rather than native sulfur; and (3) to produce large native sulfur deposits, enormous amounts of oxygenated water would need to be brought in close proximity to environments in which ample hydrocarbon supply sustains sulfate reduction. However, sulfur stable isotope data from native sulfur deposits emplaced at a stage after the formation of the host rocks indicate that the sulfur was formed in a setting with little solute exchange with the ambient environment and little supply of dissolved oxygen. We deduce that there must be a process for the formation of native sulfur in absence of an external oxidant for sulfide. We hypothesize that in systems with little solute exchange, sulfate-reducing organisms, possibly in cooperation with other anaerobic microbial partners, drive the formation of native sulfur deposits. In order to cope with sulfide stress, microbes may shift from harmful sulfide production to non-hazardous native sulfur production. We propose four possible mechanisms as a means to form native sulfur: (1) a modified sulfate reduction process that produces sulfur compounds with an intermediate oxidation state, (2) coupling of sulfide oxidation to methanogenesis that utilizes methylated compounds, acetate or carbon dioxide, (3) ammonium oxidation coupled to sulfate reduction, and (4) sulfur comproportionation of sulfate and sulfide. We show these reactions are thermodynamically favorable and especially useful in environments with multiple stressors, such as salt and dissolved sulfide, and provide evidence that microbial species functioning in such environments produce native sulfur. Integrating these insights, we argue that microbes may form large native sulfur deposits in absence of light and external oxidants such as O2, nitrate, and metal oxides. The existence of such a process would not only explain enigmatic occurrences of native sulfur in the geologic record, but also provide an explanation for cryptic sulfur and carbon cycling beneath the seabed.
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Affiliation(s)
- Amanda L. Labrado
- Department of Geological Sciences, The University of Texas at El Paso, El Paso, TX, United States
| | - Benjamin Brunner
- Department of Geological Sciences, The University of Texas at El Paso, El Paso, TX, United States
| | | | - Jörn Peckmann
- Centrum für Erdsystemforschung und Nachhaltigkeit, Universität Hamburg, Hamburg, Germany
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19
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Ausín B, Haghipour N, Wacker L, Voelker AHL, Hodell D, Magill C, Looser N, Bernasconi SM, Eglinton TI. Radiocarbon Age Offsets Between Two Surface Dwelling Planktonic Foraminifera Species During Abrupt Climate Events in the SW Iberian Margin. Paleoceanogr Paleoclimatol 2019; 34:63-78. [PMID: 30854509 PMCID: PMC6392128 DOI: 10.1029/2018pa003490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 12/23/2018] [Accepted: 12/30/2018] [Indexed: 06/09/2023]
Abstract
This study identifies temporal biases in the radiocarbon ages of the planktonic foraminifera species Globigerina bulloides and Globigerinoides ruber (white) in a sediment core from the SW Iberian margin (so-called Shackleton site). Leaching of the outer shell and measurement of the radiocarbon content of both the leachate and leached sample enabled us to identify surface contamination of the tests and its impact on their 14C ages. Incorporation of younger radiocarbon on the outer shell affected both species and had a larger impact downcore. Interspecies comparison of the 14C ages of the leached samples reveal systematic offsets with 14C ages for G. ruber being younger than G. bulloides ages during the last deglaciation and part of the Early and mid-Holocene. The greatest offsets (up to 1,030 years) were found during Heinrich Stadial 1, the Younger Dryas, and part of the Holocene. The potential factors differentially affecting these two planktonic species were assessed by complementary 14C, oxygen and carbon isotopes, and species abundance determinations. The coupled effect of bioturbation with changes in the abundance of G. ruber is invoked to account for the large age offsets. Our results highlight that 14C ages of planktonic foraminifera might be largely compromised even in settings characterized by high sediment accumulation rates. Thus, a careful assessment of potential temporal biases must be performed prior to using 14C ages for paleoclimate investigations or radiocarbon calibrations (e.g., marine calibration curve Marine13, Reimer et al., 2013, https://doi.org/10.2458/azu_js_rc.55.16947).
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Affiliation(s)
| | | | | | - Antje H. L. Voelker
- Centre of Marine Sciences (CCMAR)Universidade do AlgarveFaroPortugal
- Instituto Português do Mar e da AtmosferaLisbonPortugal
| | - David Hodell
- Department of Earth SciencesUniversity of CambridgeCambridgeUK
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20
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Meister P, Wiedling J, Lott C, Bach W, Kuhfuß H, Wegener G, Böttcher ME, Deusner C, Lichtschlag A, Bernasconi SM, Weber M. Anaerobic methane oxidation inducing carbonate precipitation at abiogenic methane seeps in the Tuscan archipelago (Italy). PLoS One 2018; 13:e0207305. [PMID: 30566474 PMCID: PMC6300204 DOI: 10.1371/journal.pone.0207305] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 10/29/2018] [Indexed: 11/21/2022] Open
Abstract
Seepage of methane (CH4) on land and in the sea may significantly affect Earth's biogeochemical cycles. However processes of CH4 generation and consumption, both abiotic and microbial, are not always clear. We provide new geochemical and isotope data to evaluate if a recently discovered CH4 seepage from the shallow seafloor close to the Island of Elba (Tuscany) and two small islands nearby are derived from abiogenic or biogenic sources and whether carbonate encrusted vents are the result of microbial or abiotic processes. Emission of gas bubbles (predominantly CH4) from unlithified sands was observed at seven spots in an area of 100 m2 at Pomonte (Island of Elba), with a total rate of 234 ml m-2 d-1. The measured carbon isotope values of CH4 of around -18‰ (VPDB) in combination with the measured δ2H value of -120‰ (VSMOW) and the inverse correlation of δ13C-value with carbon number of hydrocarbon gases are characteristic for sites of CH4 formation through abiogenic processes, specifically abiogenic formation of CH4 via reduction of CO2 by H2. The H2 for methanogenesis likely derives from ophiolitic host rock within the Ligurian accretionary prism. The lack of hydrothermal activity allows CH4 gas to become decoupled from the stagnant aqueous phase. Hence no hyperalkaline fluid is currently released at the vent sites. Within the seep area a decrease in porewater sulphate concentrations by ca. 5 mmol/l relative to seawater and a concomitant increase in sulphide and dissolved inorganic carbon (DIC) indicate substantial activity of sulphate-dependent anaerobic oxidation of methane (AOM). In absence of any other dissimilatory pathway, the δ13C-values between -17 and -5‰ in dissolved inorganic carbon and aragonite cements suggest that the inorganic carbon is largely derived from CH4. The formation of seep carbonates is thus microbially induced via anaerobic oxidation of abiotic CH4.
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Affiliation(s)
- Patrick Meister
- Department of Geodynamics and Sedimentology, University of Vienna, Vienna, Austria
| | - Johanna Wiedling
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Christian Lott
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
| | - Wolfgang Bach
- MARUM–Center for Marine Environmental Research, University of Bremen, Bremen, Germany
| | - Hanna Kuhfuß
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Gunter Wegener
- Max Planck Institute for Marine Microbiology, Bremen, Germany
- MARUM–Center for Marine Environmental Research, University of Bremen, Bremen, Germany
| | - Michael E. Böttcher
- Geochemistry & Isotope Biogeochemistry Group, Leibniz Institute for Baltic Sea Research (IOW), Warnemünde, Germany
| | | | - Anna Lichtschlag
- National Oceanography Centre, University of Southampton Water Front Campus, Southampton, United Kingdom
| | | | - Miriam Weber
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
- Max Planck Institute for Marine Microbiology, Bremen, Germany
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21
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Bernasconi SM, Müller IA, Bergmann KD, Breitenbach SFM, Fernandez A, Hodell DA, Jaggi M, Meckler AN, Millan I, Ziegler M. Reducing Uncertainties in Carbonate Clumped Isotope Analysis Through Consistent Carbonate-Based Standardization. Geochem Geophys Geosyst 2018; 19:2895-2914. [PMID: 30443200 PMCID: PMC6220777 DOI: 10.1029/2017gc007385] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 06/11/2018] [Accepted: 07/05/2018] [Indexed: 06/08/2023]
Abstract
About a decade after its introduction, the field of carbonate clumped isotope thermometry is rapidly expanding because of the large number of possible applications and its potential to solve long-standing questions in Earth Sciences. Major factors limiting the application of this method are the very high analytical precision required for meaningful interpretations, the relatively complex sample preparation procedures, and the mass spectrometric corrections needed. In this paper we first briefly review the evolution of the analytical and standardization procedures and discuss the major remaining sources of uncertainty. We propose that the use of carbonate standards to project the results to the carbon dioxide equilibrium scale can improve interlaboratory data comparability and help to solve long-standing discrepancies between laboratories and temperature calibrations. The use of carbonates reduces uncertainties related to gas preparation and cleaning procedures and ensures equal treatment of samples and standards. We present a set of carbonate standards of diverse composition, discuss how they can be used to correct for mass spectrometric biases, and demonstrate that their use significantly improves the comparability among four laboratories. We propose that the use of these standards or of a similar set of carbonate standards will improve the comparability of data across laboratories.
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Affiliation(s)
| | | | - Kristin D. Bergmann
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMAUSA
| | - Sebastian F. M. Breitenbach
- Godwin Laboratory for Palaeoclimate Research, Department of Earth SciencesUniversity of CambridgeCambridgeUK
- Now at Sediment & Isotope GeologyRuhr‐Universität BochumBochumGermany
| | | | - David A. Hodell
- Godwin Laboratory for Palaeoclimate Research, Department of Earth SciencesUniversity of CambridgeCambridgeUK
| | | | - Anna Nele Meckler
- Bjerknes Center for Climate Research and Department of Earth ScienceUniversity of BergenBergenNorway
| | | | - Martin Ziegler
- Earth Science DepartmentUtrecht UniversityUtrechtNetherlands
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22
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Rodríguez-Sanz L, Bernasconi SM, Marino G, Heslop D, Müller IA, Fernandez A, Grant KM, Rohling EJ. Penultimate deglacial warming across the Mediterranean Sea revealed by clumped isotopes in foraminifera. Sci Rep 2017; 7:16572. [PMID: 29185446 PMCID: PMC5707372 DOI: 10.1038/s41598-017-16528-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 11/13/2017] [Indexed: 11/22/2022] Open
Abstract
The variability of seawater temperature through time is a critical measure of climate change, yet its reconstruction remains problematic in many regions. Mg/Ca and oxygen isotope (δ18OC) measurements in foraminiferal carbonate shells can be combined to reconstruct seawater temperature and δ18O (δ18OSW). The latter is a measure of changes in local hydrology (e.g., precipitation/evaporation, freshwater inputs) and global ice volume. But diagenetic processes may affect foraminiferal Mg/Ca. This restricts its potential in many places, including the Mediterranean Sea, a strategic region for deciphering global climate and sea-level changes. High alkalinity/salinity conditions especially bias Mg/Ca temperatures in the eastern Mediterranean (eMed). Here we advance the understanding of both western Mediterranean (wMed) and eMed hydrographic variability through the penultimate glacial termination (TII) and last interglacial, by applying the clumped isotope (Δ47) paleothermometer to planktic foraminifera with a novel data-processing approach. Results suggest that North Atlantic cooling during Heinrich stadial 11 (HS11) affected surface-water temperatures much more in the wMed (during winter/spring) than in the eMed (during summer). The method’s paired Δ47 and δ18OC data also portray δ18OSW. These records reveal a clear HS11 freshwater signal, which attenuated toward the eMed, and also that last interglacial surface warming in the eMed was strongly amplified by water-column stratification during the deposition of the organic-rich (sapropel) interval known as S5.
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Affiliation(s)
- L Rodríguez-Sanz
- Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia.
| | - S M Bernasconi
- Geological Institute, ETH Zurich, Sonneggstr. 5, 8092, Zurich, Switzerland
| | - G Marino
- Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia.,University of Vigo, Campus Universitario, 36310, Vigo, Spain
| | - D Heslop
- Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia
| | - I A Müller
- Geological Institute, ETH Zurich, Sonneggstr. 5, 8092, Zurich, Switzerland
| | - A Fernandez
- Geological Institute, ETH Zurich, Sonneggstr. 5, 8092, Zurich, Switzerland
| | - K M Grant
- Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia
| | - E J Rohling
- Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia.,Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, S014 3ZH, UK
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23
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Pfahler V, Tamburini F, Bernasconi SM, Frossard E. A dual isotopic approach using radioactive phosphorus and the isotopic composition of oxygen associated to phosphorus to understand plant reaction to a change in P nutrition. Plant Methods 2017; 13:75. [PMID: 29021817 PMCID: PMC5613512 DOI: 10.1186/s13007-017-0227-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 09/17/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Changing the phosphorus (P) nutrition leads to changes in plant metabolism. The aim of this study was to investigate how these changes are reflected in the distribution of 33P and the isotopic composition of oxygen associated to P (δ18OP) in different plant parts of soybean (Glycine max cv. Toliman). Two P pools were extracted sequentially with 0.3 M trichloroacetic acid (TCA P) and 10 M nitric acid (HNO3; residual P). RESULTS The δ18OP of TCA P in the old leaves of the - P plants (23.8‰) significantly decreased compared to the + P plants (27.4‰). The 33P data point to an enhanced mobilisation of P from residual P in the old leaves of the - P plants compared to the + P plants. CONCLUSIONS Omitting P for 10 days lead to a translocation of P from source to sink organs in soybeans. This was accompanied by a significant lowering of the δ18OP of TCA P in the source organs due to the enzymatic hydrolysis of organic P. Combining 33P and δ18OP can provide useful insights in plant responses to P omission at an early stage.
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Affiliation(s)
- Verena Pfahler
- Department of Environmental Systems Science, ETH Zurich, Eschikon 33, 8315 Lindau, Switzerland
- Sustainable Agriculture Sciences, Rothamsted Research, Okehampton, Devon EX20 2SB UK
| | - Federica Tamburini
- Department of Environmental Systems Science, ETH Zurich, Eschikon 33, 8315 Lindau, Switzerland
| | - Stefano M. Bernasconi
- Department of Earth Sciences, ETH Zurich, Sonneggstrasse 5, 8001 Zurich, Switzerland
| | - Emmanuel Frossard
- Department of Environmental Systems Science, ETH Zurich, Eschikon 33, 8315 Lindau, Switzerland
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24
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Müller IA, Fernandez A, Radke J, van Dijk J, Bowen D, Schwieters J, Bernasconi SM. Carbonate clumped isotope analyses with the long-integration dual-inlet (LIDI) workflow: scratching at the lower sample weight boundaries. Rapid Commun Mass Spectrom 2017; 31:1057-1066. [PMID: 28402589 DOI: 10.1002/rcm.7878] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 04/07/2017] [Accepted: 04/07/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE Clumped isotope analyses (Δ47 ) of carbonates by dual inlet (DI) mass spectrometry require long integration times to reach the necessary high precision due to the low abundance of the rare isotopologue 13 C18 O16 O. Traditional DI protocols reach this only with large amounts of sample and/or a large number of replicates as a large portion of the analyte gas is wasted. We tested an improved analytical workflow that significantly reduces the sample sizes and total analysis time per sample while preserving precision and accuracy. METHODS We implemented the LIDI (long-integration dual-inlet) protocol to measure carbonates in micro-volume mode using a Kiel IV carbonate device coupled to a Thermo Scientific 253 Plus isotope ratio mass spectrometer without the new 1013 ohm amplifier technology. The LIDI protocol includes a single measurement of the sample gas (600 s integration) followed by a single measurement of the working gas (WG) with the same integration time. RESULTS The Δ47 measurements of four calcite standards over a period of 5 weeks demonstrate excellent long-term stability with a standard deviation of ±0.021 to ±0.025 ‰ for the final values of the individual aliquots. The Δ47 analyses of a coral, four foraminifera and a calcite precipitated in the laboratory demonstrate that 14 replicates of 90 to 120 μg are sufficient to achieve an external precision of ±0.007 ‰ (1SE) or of ±0.013 ‰ at the 95% confidence level. CONCLUSIONS This study demonstrates that by using a Kiel IV-253 Plus system with LIDI it is possible to achieve the same analytical precision as conventional DI measurements with at least a factor of 40 less sample material. With the new 1013 ohm resistor technology there is the potential to reduce the required sample material even more. This opens new avenues of research in paleoceanography, paleoclimatology, low-temperature diagenesis and other currently sample size limited applications. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Inigo A Müller
- Geological Institute, ETH Zürich, Sonneggstrasse 5, 8092, Zürich, Switzerland
| | - Alvaro Fernandez
- Geological Institute, ETH Zürich, Sonneggstrasse 5, 8092, Zürich, Switzerland
| | - Jens Radke
- Thermo Fisher Scientific, Hanna-Kunath-Strasse 11, 28199, Bremen, Germany
| | - Joep van Dijk
- Geological Institute, ETH Zürich, Sonneggstrasse 5, 8092, Zürich, Switzerland
| | - Devon Bowen
- Ziggurat GmbH, Rainstrasse 56, 8712, Stäfa, Switzerland
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25
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Wiedemeier DB, Lang SQ, Gierga M, Abiven S, Bernasconi SM, Früh-Green GL, Hajdas I, Hanke UM, Hilf MD, McIntyre CP, Scheider MPW, Smittenberg RH, Wacker L, Wiesenberg GLB, Schmidt MWI. Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids (BPCA). J Vis Exp 2016. [PMID: 27214064 PMCID: PMC4942176 DOI: 10.3791/53922] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Fire-derived, pyrogenic carbon (PyC), sometimes called black carbon (BC), is the carbonaceous solid residue of biomass and fossil fuel combustion, such as char and soot. PyC is ubiquitous in the environment due to its long persistence, and its abundance might even increase with the projected increase in global wildfire activity and the continued burning of fossil fuel. PyC is also increasingly produced from the industrial pyrolysis of organic wastes, which yields charred soil amendments (biochar). Moreover, the emergence of nanotechnology may also result in the release of PyC-like compounds to the environment. It is thus a high priority to reliably detect, characterize and quantify these charred materials in order to investigate their environmental properties and to understand their role in the carbon cycle. Here, we present the benzene polycarboxylic acid (BPCA) method, which allows the simultaneous assessment of PyC's characteristics, quantity and isotopic composition (13C and 14C) on a molecular level. The method is applicable to a very wide range of environmental sample materials and detects PyC over a broad range of the combustion continuum, i.e., it is sensitive to slightly charred biomass as well as high temperature chars and soot. The BPCA protocol presented here is simple to employ, highly reproducible, as well as easily extendable and modifiable to specific requirements. It thus provides a versatile tool for the investigation of PyC in various disciplines, ranging from archeology and environmental forensics to biochar and carbon cycling research.
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Affiliation(s)
| | - Susan Q Lang
- Department of Earth and Ocean Sciences, University of South Carolina
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26
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Thornalley DJR, Bauch HA, Gebbie G, Guo W, Ziegler M, Bernasconi SM, Barker S, Skinner LC, Yu J. PALEOCEANOGRAPHY. A warm and poorly ventilated deep Arctic Mediterranean during the last glacial period. Science 2015; 349:706-10. [PMID: 26273049 DOI: 10.1126/science.aaa9554] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Changes in the formation of dense water in the Arctic Ocean and Nordic Seas [the "Arctic Mediterranean" (AM)] probably contributed to the altered climate of the last glacial period. We examined past changes in AM circulation by reconstructing radiocarbon ventilation ages of the deep Nordic Seas over the past 30,000 years. Our results show that the glacial deep AM was extremely poorly ventilated (ventilation ages of up to 10,000 years). Subsequent episodic overflow of aged water into the mid-depth North Atlantic occurred during deglaciation. Proxy data also suggest that the deep glacial AM was ~2° to 3°C warmer than modern temperatures; deglacial mixing of the deep AM with the upper ocean thus potentially contributed to the melting of sea ice, icebergs, and terminal ice-sheet margins.
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Affiliation(s)
- D J R Thornalley
- Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA 02543, USA. Department of Geography, University College London, London WC1E 6BT, UK
| | - H A Bauch
- Academy of Sciences, Humanities and Literature, Mainz, and GEOMAR Helmholtz Centre for Ocean Research, 24148 Kiel, Germany
| | - G Gebbie
- Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA 02543, USA
| | - W Guo
- Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA 02543, USA
| | - M Ziegler
- Eidgenössische Technische Hochschule Zürich, 8093 Zurich, Switzerland
| | - S M Bernasconi
- Eidgenössische Technische Hochschule Zürich, 8093 Zurich, Switzerland
| | - S Barker
- School of Earth and Ocean Sciences, Cardiff University, Cardiff CF10 3XQ, UK
| | - L C Skinner
- Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
| | - J Yu
- Research School of Earth Sciences, Australian National University, Acton, ACT 0200, Australia
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27
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Meckler AN, Ziegler M, Millán MI, Breitenbach SFM, Bernasconi SM. Long-term performance of the Kiel carbonate device with a new correction scheme for clumped isotope measurements. Rapid Commun Mass Spectrom 2014; 28:1705-1715. [PMID: 24975251 DOI: 10.1002/rcm.6949] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/14/2014] [Accepted: 05/14/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Carbonate clumped isotope thermometry is a powerful new technique increasingly used in many fields in earth science. Recently, it has been shown that clumped isotope measurements can be performed with a Kiel carbonate preparation device and micro-volume analyses, allowing measurements of small (1.5-2 mg) carbonate samples. However, common data correction schemes rely on measurements of gases prepared offline, potentially leading to unrecognized biases in the results. METHODS We propose a new correction scheme for the Kiel device method including: (1) A pressure-sensitive baseline correction (PBL) of the raw beam signals; (2) Transfer of data to the absolute reference frame; (3) Correction for acid fractionation; (4) Correction for average standard offsets; (5) When necessary, correction for Δ47 scale compression based on offsets among standards with different ordering state. The long-term performance of the new scheme was tested with a large set of standard measurements (N = 432) obtained over the course of 15 months. RESULTS The PBL correction reliably removes composition-dependent artifacts, which are commonly corrected for with gas measurements, and offsets observed in micro-volume measurements when ion beams are imbalanced. We show that the shape of the PBL can vary strongly and needs to be properly characterized. Combined PBL and standard correction resulted in long-term stability with standard deviations in Δ47 of 0.012-0.016 ‰ for the five standards over the whole period, close to the average error of 0.011 ‰ observed for individual measurements consisting of 10 replicate analyses. CONCLUSIONS Our correction scheme eliminates the need for routine gas measurements, allowing for equal treatment of samples and standards with the Kiel device setup. While the PBL and standard data obtained over 15 months reveal variable mass spectrometer behavior, they provide a robust means of correction, yielding reproducible results from small carbonate samples in the long term.
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Affiliation(s)
- A Nele Meckler
- Geological Institute, ETH Zurich, Sonneggstrasse, 5, 8092, Zürich, Switzerland
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28
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Hu B, Radke J, Schlüter HJ, Heine FT, Zhou L, Bernasconi SM. A modified procedure for gas-source isotope ratio mass spectrometry: the long-integration dual-inlet (LIDI) methodology and implications for clumped isotope measurements. Rapid Commun Mass Spectrom 2014; 28:1413-1425. [PMID: 24861590 DOI: 10.1002/rcm.6909] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 03/18/2014] [Accepted: 03/27/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE High-precision stable isotope measurements in gas-source isotope ratio mass spectrometry are generally carried out by repeated comparison of the composition of an unknown sample with that of a working gas (WG) through a dual-inlet (DI). Due to the established DI protocols, however, most of the sample gas is wasted rather than measured, which is a major problem when sample size is limited. Here we propose a new methodology allowing the measurement of a much larger portion of the available sample. METHODS We tested a new measurement protocol, the long-integration dual-inlet (LIDI) method, which consists of a single measurement of the sample for 200 to 600 seconds followed by a single measurement of the WG. The isotope ratios of the sample are calculated by comparison of the beam ratios of the WG and sample at equivalent intensities of the major ion beam. RESULTS Three isotopically very different CO2 samples were analyzed. The LIDI measurements of large samples (50 to 100 µmol of CO2) measured at quasi-constant beam sizes, and of small samples (1.5 to 2 µmol of CO2) measured in micro-volume mode, generated results that are indistinguishable from the standard DI measurements for carbon, oxygen and clumped isotope compositions. The external precision of Δ47 using the LIDI protocol (~±0.007‰) is similar to that of the state of the art DI measurements. CONCLUSIONS For traditional and clumped isotope measurements of CO2, the LIDI protocol allows the measurement of a much larger portion of the sample gas rather than only ~20% of it. In addition, the sample can be measured at higher signal intensity and for longer time, allowing the measurement of smaller samples while preserving precision. We suggest that other gases commonly used for stable isotope measurements with gas-source mass spectrometry would also benefit from this new protocol.
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Affiliation(s)
- Bin Hu
- Laboratory for Earth Surface Processes, Department of Geography, Peking University, 100871, Beijing, China; Geological Institute, ETH Zürich, 8092, Zürich, Switzerland
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Menon M, Rousseva S, Nikolaidis NP, van Gaans P, Panagos P, de Souza DM, Ragnarsdottir KV, Lair GJ, Weng L, Bloem J, Kram P, Novak M, Davidsdottir B, Gisladottir G, Robinson DA, Reynolds B, White T, Lundin L, Zhang B, Duffy C, Bernasconi SM, de Ruiter P, Blum WEH, Banwart SA. SoilTrEC: a global initiative on critical zone research and integration. Environ Sci Pollut Res Int 2014; 21:3191-3195. [PMID: 24310904 DOI: 10.1007/s11356-013-2346-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 11/04/2013] [Indexed: 06/02/2023]
Abstract
Soil is a complex natural resource that is considered non-renewable in policy frameworks, and it plays a key role in maintaining a variety of ecosystem services (ES) and life-sustaining material cycles within the Earth's Critical Zone (CZ). However, currently, the ability of soil to deliver these services is being drastically reduced in many locations, and global loss of soil ecosystem services is estimated to increase each year as a result of many different threats, such as erosion and soil carbon loss. The European Union Thematic Strategy for Soil Protection alerts policy makers of the need to protect soil and proposes measures to mitigate soil degradation. In this context, the European Commission-funded research project on Soil Transformations in European Catchments (SoilTrEC) aims to quantify the processes that deliver soil ecosystem services in the Earth's Critical Zone and to quantify the impacts of environmental change on key soil functions. This is achieved by integrating the research results into decision-support tools and applying methods of economic valuation to soil ecosystem services. In this paper, we provide an overview of the SoilTrEC project, its organization, partnerships and implementation.
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Affiliation(s)
- Manoj Menon
- Kroto Research Institute, University of Sheffield, North Campus, Broad Lane, Sheffield, S3 7HQ, UK,
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30
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Méhay S, Früh-Green GL, Lang SQ, Bernasconi SM, Brazelton WJ, Schrenk MO, Schaeffer P, Adam P. Record of archaeal activity at the serpentinite-hosted Lost City Hydrothermal Field. Geobiology 2013; 11:570-92. [PMID: 24118888 DOI: 10.1111/gbi.12062] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 09/06/2013] [Indexed: 05/22/2023]
Abstract
Samples of young, outer surfaces of brucite-carbonate deposits from the ultramafic-hosted Lost City hydrothermal field were analyzed for DNA and lipid biomarker distributions and for carbon and hydrogen stable isotope compositions of the lipids. Methane-cycling archaeal communities, notably the Lost City Methanosarcinales (LCMS) phylotype, are specifically addressed. Lost City is unlike all other hydrothermal systems known to date and is characterized by metal- and CO2 -poor, high pH fluids with high H2 and CH4 contents resulting from serpentinization processes at depth. The archaeal fraction of the microbial community varies widely within the Lost City chimneys, from 1-81% and covaries with concentrations of hydrogen within the fluids. Archaeal lipids include isoprenoid glycerol di- and tetraethers and C25 and C30 isoprenoid hydrocarbons (pentamethylicosane derivatives - PMIs - and squalenoids). In particular, unsaturated PMIs and squalenoids, attributed to the LCMS archaea, were identified for the first time in the carbonate deposits at Lost City and probably record processes exclusively occurring at the surface of the chimneys. The carbon isotope compositions of PMIs and squalenoids are remarkably heterogeneous across samples and show highly (13) C-enriched signatures reaching δ(13) C values of up to +24.6‰. Unlike other environments in which similar structural and isotopic lipid heterogeneity has been observed and attributed to diversity in the archaeal assemblage, the lipids here appear to be synthesized solely by the LCMS. Some of the variations in lipid isotope signatures may, in part, be due to unusual isotopic fractionation during biosynthesis under extreme conditions. However, we argue that the diversity in archaeal abundances, lipid structure and carbon isotope composition rather reflects the ability of the LCMS archaeal biofilms to adapt to chemical gradients in the hydrothermal chimneys and possibly to perform either methanotrophy or methanogenesis using dissolved inorganic carbon, methane or formate as a function of the prevailing environmental conditions.
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MESH Headings
- Archaea/classification
- Archaea/genetics
- Archaea/metabolism
- Bacteria/classification
- Bacteria/genetics
- Bacteria/metabolism
- Biota
- Carbon/analysis
- DNA, Archaeal/chemistry
- DNA, Archaeal/genetics
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Genes, rRNA
- Hot Springs/microbiology
- Hydrogen/analysis
- Lipids/analysis
- RNA, Archaeal/genetics
- RNA, Bacterial/genetics
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
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Affiliation(s)
- S Méhay
- Department of Earth Sciences, ETH Zurich, Zurich, Switzerland
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31
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Bernasconi SM, Hu B, Wacker U, Fiebig J, Breitenbach SFM, Rutz T. Background effects on Faraday collectors in gas-source mass spectrometry and implications for clumped isotope measurements. Rapid Commun Mass Spectrom 2013; 27:603-612. [PMID: 23413219 DOI: 10.1002/rcm.6490] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 11/09/2012] [Accepted: 12/13/2012] [Indexed: 06/01/2023]
Abstract
RATIONALE The measurement of the abundances of minor isotopologues by mass spectrometry requires correction of subtle non-linearities in the mass spectrometer that cause deviations in the relationship between actual and measured isotope ratios. Here we show that negative backgrounds on the Faraday cups recording the minor ion beams are the cause of the observed non-linearities in the measurement of CO(2) isotopologues, and propose a new correction procedure for clumped isotope measurements. METHODS We carefully investigated the cause of non-linearity effects in the measurement of the abundance of (13)C(18)O(16)O, a minor isotopologue of CO(2) with m/z 47, on two different mass spectrometers. By using gases of different composition with close to stochastic and with non-random distribution of isotopes we demonstrate that the apparent dependence of the excess abundance of the isotopologue of m/z 47 on the bulk isotopic composition of CO(2) is due to a background interference that is linearly dependent on the partial pressure of the gas in the source of the mass spectrometer. CONCLUSIONS Background determination with gas flowing into the source of the mass spectrometer is necessary for accurate clumped isotope measurements of CO(2). Background corrections can be performed accurately if the slit width of the m/z 44 Faraday cup significantly exceeds that of the one for m/z 47, using a correlation between m/z 44 signal intensity and the corresponding minimum in m/z 47 background. We propose two new correction schemes that reduce the time-consuming measurement of gases of different bulk isotopic compositions. These findings may also be relevant for the measurement of other rare isotopologues by mass spectrometry.
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32
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Lang SQ, Früh-Green GL, Bernasconi SM, Butterfield DA. Sources of organic nitrogen at the serpentinite-hosted Lost City hydrothermal field. Geobiology 2013; 11:154-169. [PMID: 23346942 DOI: 10.1111/gbi.12026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 12/18/2012] [Indexed: 06/01/2023]
Abstract
The reaction of ultramafic rocks with water during serpentinization at moderate temperatures results in alkaline fluids with high concentrations of reduced chemical compounds such as hydrogen and methane. Such environments provide unique habitats for microbial communities capable of utilizing these reduced compounds in present-day and, possibly, early Earth environments. However, these systems present challenges to microbial communities as well, particularly due to high fluid pH and possibly the availability of essential nutrients such as nitrogen. Here we investigate the source and cycling of organic nitrogen at an oceanic serpentinizing environment, the Lost City hydrothermal field (30°N, Mid-Atlantic Ridge). Total hydrolizable amino acid (THAA) concentrations in the fluids range from 736 to 2300 nm and constitute a large fraction of the dissolved organic carbon (2.5-15.1%). The amino acid distributions, and the relative concentrations of these compounds across the hydrothermal field, indicate they most likely derived from chemolithoautotrophic production. Previous studies have identified the presence of numerous nitrogen fixation genes in the fluids and the chimneys. Organic nitrogen in actively venting chimneys has δ(15) N values as low as 0.1‰ which is compatible with biological nitrogen fixation. Total hydrolizable amino acids in the chimneys are enriched in (13) C by 2-7‰ compared to bulk organic matter. The distribution and absolute δ(13) C(THAA) values are compatible with a chemolithoautotrophic source, an attribution also supported by molar organic C/N ratios in most active chimneys (4.1-5.5) which are similar to those expected for microbial communities. In total, these data indicate nitrogen is readily available to microbial communities at Lost City.
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Affiliation(s)
- S Q Lang
- Department of Earth Sciences, ETH Zürich, Zurich, Switzerland
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33
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Pfahler V, Dürr-Auster T, Tamburini F, M Bernasconi S, Frossard E. 18O enrichment in phosphorus pools extracted from soybean leaves. New Phytol 2013; 197:186-193. [PMID: 23106517 DOI: 10.1111/j.1469-8137.2012.04379.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 09/08/2012] [Indexed: 05/28/2023]
Abstract
The objective of this study was to investigate the isotopic composition of oxygen bound to phosphate (δ(18)O-PO(4)) in different phosphorus (P) pools in plant leaves. As a model plant we used soybean (Glycine max cv Toliman) grown in the presence of ample P in hydroponic cultures. The leaf blades were extracted with 0.3 M trichloroacetic acid (TCA) and with 10 M nitric acid. These extractions allowed measurement of the TCA-soluble reactive P (TCA P) that is rapidly cycled within the cell and the total leaf P. The difference between total leaf P and TCA P yielded the structural P which includes organic P compounds not extractable by TCA. P uptake and its translocation and transformation within the soybean plants lead to an (18)O enrichment of TCA P (δ(18)O-PO(4) between 16.9 and 27.5‰) and structural P (δ(18)O-PO(4) between 42.6 and 68.0 ‰) compared with 12.4‰ in the phosphate in the nutrient solution. δ(18)O values of phosphate extracted from soybean leaves grown under optimal conditions are greater than the δ(18)O-PO(4) values of the provided P source. Furthermore, the δ(18)O-PO(4) of TCA P seems to be controlled by the δ(18)O of leaf water and the activity of inorganic pyrophosphatase or other pyrophosphatases.
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Affiliation(s)
- Verena Pfahler
- Institute of Agricultural Sciences, ETH Zurich, Eschikon 33, 8315, Lindau, Switzerland
| | - Thilo Dürr-Auster
- Institute of Agricultural Sciences, ETH Zurich, Eschikon 33, 8315, Lindau, Switzerland
| | - Federica Tamburini
- Institute of Agricultural Sciences, ETH Zurich, Eschikon 33, 8315, Lindau, Switzerland
| | | | - Emmanuel Frossard
- Institute of Agricultural Sciences, ETH Zurich, Eschikon 33, 8315, Lindau, Switzerland
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34
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Jaeschke A, Jørgensen SL, Bernasconi SM, Pedersen RB, Thorseth IH, Früh-Green GL. Microbial diversity of Loki's Castle black smokers at the Arctic Mid-Ocean Ridge. Geobiology 2012; 10:548-561. [PMID: 23006788 DOI: 10.1111/gbi.12009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 08/16/2012] [Indexed: 06/01/2023]
Abstract
Hydrothermal vent systems harbor rich microbial communities ranging from aerobic mesophiles to anaerobic hyperthermophiles. Among these, members of the archaeal domain are prevalent in microbial communities in the most extreme environments, partly because of their temperature-resistant and robust membrane lipids. In this study, we use geochemical and molecular microbiological methods to investigate the microbial diversity in black smoker chimneys from the newly discovered Loki's Castle hydrothermal vent field on the Arctic Mid-Ocean Ridge (AMOR) with vent fluid temperatures of 310-320 °C and pH of 5.5. Archaeal glycerol dialkyl glycerol tetraether lipids (GDGTs) and H-shaped GDGTs with 0-4 cyclopentane moieties were dominant in all sulfide samples and are most likely derived from both (hyper)thermophilic Euryarchaeota and Crenarchaeota. Crenarchaeol has been detected in low abundances in samples derived from the chimney exterior indicating the presence of Thaumarchaeota at lower ambient temperatures. Aquificales and members of the Epsilonproteobacteria were the dominant bacterial groups detected. Our observations based on the analysis of 16S rRNA genes and biomarker lipid analysis provide insight into microbial communities thriving within the porous sulfide structures of active and inactive deep-sea hydrothermal vents. Microbial cycling of sulfur, hydrogen, and methane by archaea in the chimney interior and bacteria in the chimney exterior may be the prevailing biogeochemical processes in this system.
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MESH Headings
- Arctic Regions
- Atlantic Ocean
- Biota
- Cluster Analysis
- DNA, Archaeal/chemistry
- DNA, Archaeal/genetics
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Genes, rRNA
- Hot Temperature
- Hydrogen-Ion Concentration
- Hydrothermal Vents/microbiology
- Lipids/analysis
- Phylogeny
- RNA, Archaeal/genetics
- RNA, Bacterial/genetics
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
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Affiliation(s)
- A Jaeschke
- Department of Earth Sciences, ETH Zurich, Zurich, Switzerland.
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35
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Huber B, Bernasconi SM, Pannatier EG, Luster J. A simple method for the removal of dissolved organic matter and δ15N analysis of NO3(-) from freshwater. Rapid Commun Mass Spectrom 2012; 26:1475-1480. [PMID: 22592991 DOI: 10.1002/rcm.6243] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
RATIONALE Stable isotopes of nitrogen in nitrate (NO(3)(-)) are frequently used to identify nitrate sources and to study nitrogen (N) transformation processes, but the measurement methods available are generally rather labor intensive and/or costly, and dissolved organic matter (DOM) can interfere with the δ(15)N signature of nitrate. We therefore have developed a simple cleanup procedure for freshwater samples with low nitrate and high DOM concentrations. METHODS Nitrate and DOM are extracted from a freeze-dried water sample by using a concentrated sodium hydroxide solution. By the subsequent addition of acetone, two liquid layers are formed, and nitrate migrates into the acetone while DOM remains in the concentrated NaOH solution, thus separating the nitrate from the DOM. For nitrogen isotope analysis, purified nitrate salts are combusted at 1030 °C to produce N(2) gas in an elemental analyzer (EA) coupled to an isotope ratio mass spectrometer (IRMS). RESULTS With this novel technique up to 99% of DOM could be removed from river water and soil solutions. The method has been tested for sample amounts as small as 4 µmol NO(3)(-) with a precision of <0.1‰ (1SD). Nitrate standards are reproduced accurately without any blank correction. CONCLUSIONS The benefits of this method are the lack of interferences derived from DOM on the δ(15)N signature and the ease of sample preparation.
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Affiliation(s)
- Benjamin Huber
- Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
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36
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Tamburini F, Pfahler V, Bünemann EK, Guelland K, Bernasconi SM, Frossard E. Oxygen isotopes unravel the role of microorganisms in phosphate cycling in soils. Environ Sci Technol 2012; 46:5956-5962. [PMID: 22545923 DOI: 10.1021/es300311h] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Phosphorus (P) is considered the ultimate limiting nutrient for plants in most natural systems and changes in the distribution of inorganic and organic P forms during soil development have been well documented. In particular, microbial activity has been shown to be an important control on P cycling but its contribution in building up the pool of plant-available P during soil development is still poorly quantified. To determine the importance of different biological processes on P cycling, we analyzed the isotopic composition of oxygen in phosphate (δ(18)O-Pi) from the parent material, soil microorganisms, the available P pool, and from the vegetation along a 150-year soil chronosequence of a glacier forefield. Our results show that at all sites, δ(18)O-Pi of microbial Pi is within the range expected for the temperature-dependent equilibrium between phosphate and water. In addition, the isotopic signature of available Pi is close to the signature of microbial Pi, independently of the contribution of parent material Pi, vegetation Pi or Pi released from organic matter mineralization. Thus, we show that phosphate is cycled through soil microorganisms before being released to the available pool. This isotopic approach demonstrates for the first time in the field and over long time scales, and not only through controlled experiments, the role of the microbial activity in cycling of P in soils.
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Affiliation(s)
- Federica Tamburini
- Institute of Agricultural Sciences, ETH Zurich, 8092 Zurich, Switzerland.
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37
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Zumsteg A, Luster J, Göransson H, Smittenberg RH, Brunner I, Bernasconi SM, Zeyer J, Frey B. Bacterial, archaeal and fungal succession in the forefield of a receding glacier. Microb Ecol 2012; 63:552-64. [PMID: 22159526 DOI: 10.1007/s00248-011-9991-8] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Accepted: 11/28/2011] [Indexed: 05/10/2023]
Abstract
Glacier forefield chronosequences, initially composed of barren substrate after glacier retreat, are ideal locations to study primary microbial colonization and succession in a natural environment. We characterized the structure and composition of bacterial, archaeal and fungal communities in exposed rock substrates along the Damma glacier forefield in central Switzerland. Soil samples were taken along the forefield from sites ranging from fine granite sand devoid of vegetation near the glacier terminus to well-developed soils covered with vegetation. The microbial communities were studied with genetic profiling (T-RFLP) and sequencing of clone libraries. According to the T-RFLP profiles, bacteria showed a high Shannon diversity index (H) (ranging from 2.3 to 3.4) with no trend along the forefield. The major bacterial lineages were Proteobacteria, Actinobacteria, Acidobacteria, Firmicutes and Cyanobacteria. An interesting finding was that Euryarchaeota were predominantly colonizing young soils and Crenarchaeota mainly mature soils. Fungi shifted from an Ascomycota-dominated community in young soils to a more Basidiomycota-dominated community in old soils. Redundancy analysis indicated that base saturation, pH, soil C and N contents and plant coverage, all related to soil age, correlated with the microbial succession along the forefield.
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Affiliation(s)
- Anita Zumsteg
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903, Birmensdorf, Switzerland
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38
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Lang SQ, Bernasconi SM, Früh-Green GL. Stable isotope analysis of organic carbon in small (µg C) samples and dissolved organic matter using a GasBench preparation device. Rapid Commun Mass Spectrom 2012; 26:9-16. [PMID: 22215572 DOI: 10.1002/rcm.5287] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The stable isotopes of organic matter can provide valuable information on carbon cycling dynamics, microbial metabolisms, and past climates. Since bulk measurements may mask dynamic changes to critical portions of the organic pool, researchers are increasingly isolating individual compounds for isotopic analysis. The amount of carbon isolated is frequently small, requiring specialized equipment for its analysis. We present a simple and accurate method to measure the δ(13)C values of µg-amounts of organic compounds and dissolved organic matter in freshwaters using wet oxidation and a GasBench II preparation device. Samples containing 3 µg C can be analyzed with a precision of <0.4‰. For samples containing 1.2 µg C, the precision is <0.8‰. The blank is estimated to be ~0.2 µg C. The accuracy of the method is demonstrated for a wide range of compounds including those that are difficult to oxidize such as humic acid and phthalic acid. The δ(13)C values of DOC from river and riparian ground water determined by this method are comparable with those determined with an elemental analyzer on freeze-dried samples of DOC. The low detection limit and the ease with which it can be combined with isolation techniques such as liquid chromatography make this technique attractive for the off-line analysis of organic compounds, and open new possibilities for the development of methodologies for compound-specific carbon isotope analysis of complex mixtures separated by HPLC.
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Affiliation(s)
- Susan Q Lang
- Department of Earth Sciences, ETH Zürich, 8092 Zürich, Switzerland.
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39
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Brunner B, Einsiedl F, Arnold GL, Müller I, Templer S, Bernasconi SM. The reversibility of dissimilatory sulphate reduction and the cell-internal multi-step reduction of sulphite to sulphide: insights from the oxygen isotope composition of sulphate. Isotopes Environ Health Stud 2011; 48:33-54. [PMID: 22128782 DOI: 10.1080/10256016.2011.608128] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Dissimilatory sulphate reduction (DSR) leads to an overprint of the oxygen isotope composition of sulphate by the oxygen isotope composition of water. This overprint is assumed to occur via cell-internally formed sulphuroxy intermediates in the sulphate reduction pathway. Unlike sulphate, the sulphuroxy intermediates can readily exchange oxygen isotopes with water. Subsequent to the oxygen isotope exchange, these intermediates, e.g. sulphite, are re-oxidised by reversible enzymatic reactions to sulphate, thereby incorporating the oxygen used for the re-oxidation of the sulphur intermediates. Consequently, the rate and expression of DSR-mediated oxygen isotope exchange between sulphate and water depend not only on the oxygen isotope exchange between sulphuroxy intermediates and water, but also on cell-internal forward and backward reactions. The latter are the very same processes that control the extent of sulphur isotope fractionation expressed by DSR. Recently, the measurement of multiple sulphur isotope fractionation has successfully been applied to obtain information on the reversibility of individual enzymatically catalysed steps in DSR. Similarly, the oxygen isotope signature of sulphate has the potential to reveal complementary information on the reversibility of DSR. The aim of this work is to assess this potential. We derived a mathematical model that links sulphur and oxygen isotope effects by DSR, assuming that oxygen isotope effects observed in the oxygen isotopic composition of ambient sulphate are controlled by the oxygen isotope exchange between sulphite and water and the successive cell-internal oxidation of sulphite back to sulphate. Our model predicts rapid DSR-mediated oxygen isotope exchange for cases where the sulphur isotope fractionation is large and slow exchange for cases where the sulphur isotope fractionation is small. Our model also demonstrates that different DSR-mediated oxygen isotope equilibrium values are observed, depending on the importance of oxygen isotope exchange between sulphite and water relative to the re-oxidation of sulphite. Comparison of model results to experimental data further leads to the conclusion that sulphur isotope fractionation in the reduction of sulphite to sulphide is not a single-step process.
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40
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Huber B, Bernasconi SM, Luster J, Pannatier EG. A new isolation procedure of nitrate from freshwater for nitrogen and oxygen isotope analysis. Rapid Commun Mass Spectrom 2011; 25:3056-62. [PMID: 21953960 DOI: 10.1002/rcm.5199] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The nitrogen (δ(15)N) and oxygen isotope (δ(18)O) analysis of nitrate (NO(3)(-)) from aqueous samples can be used to determine nitrate sources and to study N transformation processes. For these purposes, several methods have been developed; however, none of them allows an accurate, fast and inexpensive analysis. Here, we present a new simple method for the isolation of nitrate, which is based on the different solubilities of inorganic salts in an acetone/hexane/water mixture. In this solvent, all major nitrate salts are soluble, whereas all other oxygen-bearing compounds such as most inorganic carbonates, sulfates, and phosphates are not. Nitrate is first concentrated by freeze-drying, dissolved in the ternary solvent and separated from insoluble compounds by centrifugation. Anhydrous barium nitrate is then precipitated in the supernatant solution by adding barium iodide. For δ(18)O analysis, dried Ba(NO(3))(2) samples are directly reduced in a high-temperature conversion system to CO and measured on-line using isotope ratio mass spectrometry (IRMS). For δ(15)N analysis, samples are combusted in an elemental analyzer (EA) coupled to an IRMS system. The method has been tested down to 20 µmol NO(3)(-) with a reproducibility (1SD) of 0.1‰ for nitrogen and 0.2-0.4‰ for oxygen isotopes. For nitrogen we observed a small consistent (15) N enrichment of +0.2‰, probably due to an incomplete precipitation process and, for oxygen, a correction for the incorporation of water in the precipitated Ba(NO(3))(2) has to be applied. Apart from being robust, this method is highly efficient and low in cost.
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Affiliation(s)
- Benjamin Huber
- Swiss Federal Research Institute WSL, Birmensdorf, Switzerland.
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41
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Codron D, Sponheimer M, Codron J, Hammer S, Tschuor A, Braun U, Bernasconi SM, Clauss M. Tracking the fate of digesta 13C and 15N compositions along the ruminant gastrointestinal tract: Does digestion influence the relationship between diet and faeces? EUR J WILDLIFE RES 2011. [DOI: 10.1007/s10344-011-0581-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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42
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Breitenbach SFM, Bernasconi SM. Carbon and oxygen isotope analysis of small carbonate samples (20 to 100 µg) with a GasBench II preparation device. Rapid Commun Mass Spectrom 2011; 25:1910-1914. [PMID: 21638367 DOI: 10.1002/rcm.5052] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
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43
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Codron D, Codron J, Sponheimer M, Bernasconi SM, Clauss M. When animals are not quite what they eat: diet digestibility influences 13C-incorporation rates and apparent discrimination in a mixed-feeding herbivore. CAN J ZOOL 2011. [DOI: 10.1139/z11-010] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The stable carbon isotope composition of animal tissues represents the weighted sum of the variety of food sources eaten. If sources differ in digestibility, tissues may overrepresent intake of more digestible items and faeces may overrepresent less digestible items. We tested this idea using whole blood and faeces of goats ( Capra hircus L., 1758) fed different food mixtures of C3 lucerne ( Medicago sativa L.) and C4 grass ( Themeda triandra Forssk.). Although blood and faecal δ13C values were broadly consistent with diet, results indicate mismatch between consumer and diet isotope compositions: both materials overrepresented the C3 (lucerne) component of diets. Lucerne had lower fibre digestibility than T. triandra, which explains the results for faeces, whereas underrepresentation of dietary C4 in blood is consistent with low protein content of the grass hay. A diet switch experiment revealed an important difference in 13C-incorporation rates across diets, which were slower for grass than lucerne diets, and in fact equilibrium states were not reached for all diets. Although more research is needed to link digestive kinetics with isotope incorporation, these results provide evidence for nonlinear relationships between consumers and their diets, invoking concerns about the conceptual value of “discrimination factors” as the prime currency for contemporary isotope ecology.
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Affiliation(s)
- Daryl Codron
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zürich, Switzerland
- School of Biological and Conservation Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209, Republic of South Africa
| | - Jacqui Codron
- School of Biological and Conservation Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209, Republic of South Africa
| | - Matt Sponheimer
- Department of Anthropology, University of Colorado at Boulder, Boulder, CO 80309, USA
| | | | - Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zürich, Switzerland
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44
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Weiner T, Mazeh S, Tamburini F, Frossard E, Bernasconi SM, Chiti T, Angert A. A method for analyzing the δ18O of resin-extractable soil inorganic phosphate. Rapid Commun Mass Spectrom 2011; 25:624-628. [PMID: 21290449 DOI: 10.1002/rcm.4899] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Improved tools for tracing phosphate transformations in soils are much needed, and can lead to a better understanding of the terrestrial phosphorus cycle. The oxygen stable isotopes in soil phosphate are still not exploited in this regard. Here we present a method for measuring the oxygen stable isotopes in a fraction of the soil phosphate which is rapidly available to plants, the resin-extractable P. This method is based on extracting available phosphate from the soil with anion-exchange membranes, soil organic matter removal by a resin, purification by precipitation as cerium phosphate, and finally precipitation as silver phosphate. The purified silver phosphate samples are then measured by a high-temperature elemental analyzer (HT-EA) coupled in continuous flow mode to an isotope ratio mass spectrometer. Testing the method with Mediterranean and semi-arid soils showed no artifacts, as well as good reproducibility in the same order as that of the HT-EA analytical uncertainty (0.3‰).
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Affiliation(s)
- Tal Weiner
- The Institute of Earth Sciences, The Hebrew University of Jerusalem, Israel
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45
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Schmid TW, Bernasconi SM. An automated method for 'clumped-isotope' measurements on small carbonate samples. Rapid Commun Mass Spectrom 2010; 24:1955-1963. [PMID: 20552704 DOI: 10.1002/rcm.4598] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Clumped-isotope geochemistry deals with the state of ordering of rare isotopes in molecules, in particular with their tendency to form bonds with other rare isotopes rather than with the most abundant ones. Among its possible applications, carbonate clumped-isotope thermometry is the one that has gained most attention because of the wide potential of applications in many disciplines of earth sciences. Clumped-isotope thermometry allows reconstructing the temperature of formation of carbonate minerals without knowing the isotopic composition of the water from which they were formed. This feature enables new approaches in paleothermometry. The currently published method is, however, limited by sample weight requirements of 10-15 mg and because measurements are performed manually. In this paper we present a new method using an automated sample preparation device coupled to an isotope ratio mass spectrometer. The method is based on the repeated analysis (n = 6-8) of 200 microg aliquots of sample material and completely automated measurements. In addition, we propose to use precisely calibrated carbonates spanning a wide range in Delta(47) instead of heated gases to correct for isotope effects caused by the source of the mass spectrometer, following the principle of equal treatment of the samples and standards. We present data for international standards (NBS 19 and LSVEC) and different carbonates formed at temperatures exceeding 600 degrees C to show that precisions in the range of 10 to 15 ppm (1 SE) can be reached for repeated analyses of a single sample. Finally, we discuss and validate the correction procedure based on high-temperature carbonates instead of heated gases.
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Affiliation(s)
- Thomas W Schmid
- Geological Institute, ETH Zurich, CH-8092 Zurich, Switzerland.
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46
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Thevenon F, Anselmetti FS, Bernasconi SM, Schwikowski M. Mineral dust and elemental black carbon records from an Alpine ice core (Colle Gnifetti glacier) over the last millennium. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jd011490] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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47
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Hofstetter TB, Schwarzenbach RP, Bernasconi SM. Assessing transformation processes of organic compounds using stable isotope fractionation. Environ Sci Technol 2008; 42:7737-7743. [PMID: 19031854 DOI: 10.1021/es801384j] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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Hofstetter TB, Bernasconi SM, Schwarzenbach RP, Kretzschmar R. New methods for the environmental chemist's toolbox. Environ Sci Technol 2008; 42:7727. [PMID: 19031848 DOI: 10.1021/es802771t] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Affiliation(s)
- Thomas B Hofstetter
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology (ETH) Zurich
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Bernasconi SM, Tordi N, Ruiz J, Parratte B. Changes in oxygen uptake, shoulder muscles activity, and propulsion cycle timing during strenuous wheelchair exercise. Spinal Cord 2006; 45:468-74. [PMID: 17060923 DOI: 10.1038/sj.sc.3101989] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN Cross-over study. OBJECTIVE To determine the effect of strenuous wheelchair exercise on oxygen uptake (VO2 ), muscle activity and propulsion cycle timing (including the push time and recovery time during one full arm cycle). SETTING Laboratory of Sport Sciences at the University of France-Comte in France. METHODS Two exercise bouts of 6-min duration were performed at a constant workload: (1) non-fatigable exercise (moderate workload) and (2) fatigable exercise (heavy workload). Measurement of VO2, surface electromyographic activity (EMG) from shoulder muscles, and temporal parameters of wheelchair ergometer propulsion were collected from eight able-bodied men (26+/-4 years). RESULTS A progressive increase in VO2 associated with EMG alterations (P<0.05), and a decrease of the cycle and recovery time (P<0.05) during the heavy exercise. Whereas the push time remained constant, an increased muscle activation time (P<0.05) was found during heavy exercise. CONCLUSION Observations during wheelchair ergometry indicate the development of fatigue and inefficient muscle coordination, which may contribute to deleterious stress distributions at the shoulder joint, increasing susceptibility to injury.
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Affiliation(s)
- S M Bernasconi
- 1EA 3920 Physiopathologie cardiovasculaire et prévention, Laboratory of Sport Sciences, University of Franche-comte, Besançon, France
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Treydte AC, Bernasconi SM, Kreuzer M, Edwards PJ. DIET OF THE COMMON WARTHOG (PHACOCHOERUS AFRICANUS) ON FORMER CATTLE GROUNDS IN A TANZANIAN SAVANNA. J Mammal 2006. [DOI: 10.1644/05-mamm-a-336r2.1] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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