Project

Back to overview

Tracking glacial cycles across Eurasia using lipid biomarkers in loess-paleosols-sequences

Applicant Zech Roland
Number 131670
Funding scheme Ambizione
Research institution Geologisches Institut ETH Zürich
Institution of higher education ETH Zurich - ETHZ
Main discipline Geology
Start/End 01.01.2011 - 31.12.2013
Approved amount 490'870.00
Show all

All Disciplines (2)

Discipline
Geology
Pedology

Keywords (16)

Loess; paleosols; lipid biomarkers; isotopes; paleoclimatology; glacial cycles; Loess; paleosols; biomarkers; isotopes; paleoclimatology; Quaternary; glacial cycles; alkanes; fatty acids; GDGTs

Lay Summary (German)

Lead
Loess-Paleoboeden dokumentieren die Abfolge der Eiszeiten und Warmzeiten waehrend des Quartaers (der letzten 2,6 Mio Jahre) und sind wertvolle Archive der Klima- und Umweltgeschichte. Ihr Potential konnte aber bislang nicht umfaenglich wissenschaftlich ausgeschoepft werden, vor allem da es an Methoden fehlt, quantitative Informationen zu Klima- und Landschaftsaenderungen zu erhalten.
Lay summary

Ziele und Ergebnisse des Forschungsprojektes

Ziel des Forschungsprojektes war es, moderne geochemische Methoden in verschiedenen Loess-Paleoboeden von Europa ueber Zentralasien bis nach Sibirien anzuwenden, um einen Beitrag zur Rekonstruktion der Umweltbedingungen waehrend der Eiszeiten zu liefern. Blattwachse in den untersuchten Loess-Paleoboeden zeigen, dass vermutlich selbst in den Eiszeiten durchweg Laubbaeume in Sueosteuropa, Zentralasien und Suedsibirien vorhanden waren. Die Deuterium Isotopie der Blattwachse dokumentiert die niedrigeren Temperaturen waehrend der Kaltzeiten. Die GDGTs (Membranbestandteile von Bodenbakterien) dagegen zeigen keine konsistenten Veraenderungen und beduerfen weiterer Erforschung.

Wissenschaftlicher und gesellschaftlicher Kontext

Da grosse Mengen an Kohlenstoff in Permafrostboeden gespeichert sind und erst Recht in der letzten Eiszeit gespeichert waren, sollten weitere Forschungen angestrebt werden, das einstige Klima in Sibirien zu rekonstruieren und Menge, Alter und Stabilitaet des organischen Kohlenstoffs in sibirischen Boeden zu untersuchen. Vor allem die Kombination Deuteriumisotopie an Blattwachsen und Sauerstoffisotopie an pflanzlichen Zuckern hat enormes Potential fuer weitere Klima- und Umweltrekonstruktion anhand von Loess-Paleoboeden und Seesedimenten.

Direct link to Lay Summary Last update: 10.02.2014

Responsible applicant and co-applicants

Employees

Publications

Publication
A 220 ka terrestrial delta O-18 and deuterium excess biomarker record from an eolian permafrost paleosol sequence, NE-Siberia
Zech Michael, Tuthorn Mario, Detsch Florian, Rozanski Kazimierz, Zech Roland, Zoeller Ludwig, Zech Wolfgang, Glaser Bruno (2013), A 220 ka terrestrial delta O-18 and deuterium excess biomarker record from an eolian permafrost paleosol sequence, NE-Siberia, in CHEMICAL GEOLOGY, 360, 220-230.
Humid glacials, arid interglacials? Critical thoughts on pedogenesis and paleoclimate based on multi-proxy analyses of the loess-paleosol sequence Crvenka, Northern Serbia
Zech Roland, Zech Michael, Markovic Slobodan, Hambach Ulrich, Huang Yongsong (2013), Humid glacials, arid interglacials? Critical thoughts on pedogenesis and paleoclimate based on multi-proxy analyses of the loess-paleosol sequence Crvenka, Northern Serbia, in PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY, 387, 165-175.
Impact of geomagnetic events on atmospheric chemistry and dynamics
Suter I., Zech R., Anet J., Peter T. (2013), Impact of geomagnetic events on atmospheric chemistry and dynamics, in Climate of the Past Discussion, 9, 6605-6633.
On the stratigraphic integrity of leaf-wax biomarkers in loess-paleosols
Häggi C., Zech R., McIntyre C., Eglinton T. (2013), On the stratigraphic integrity of leaf-wax biomarkers in loess-paleosols, in Biogeosciences Discussion, 10, 16903-1692.
A permafrost glacial hypothesis – Permafrost carbon might help explaining the Pleistocene ice ages
Zech Roland (2012), A permafrost glacial hypothesis – Permafrost carbon might help explaining the Pleistocene ice ages, in Quaternary Science Journal - Eiszeitalter & Gegenwart, 61, 84-92.
Branched glycerol dialkyl glycerol tetraethers in Pleistocene loess-paleosol sequences: Three case studies
Zech R, Gao L, Tarozo R, Huang Y (2012), Branched glycerol dialkyl glycerol tetraethers in Pleistocene loess-paleosol sequences: Three case studies, in ORGANIC GEOCHEMISTRY, 53, 38-44.
High carbon sequestration in Siberian permafrost loess-paleosols during glacials
Zech Roland, Huang Yongsong, Zech Michael, Tarozo Rafael, Zech Wolfgang (2011), High carbon sequestration in Siberian permafrost loess-paleosols during glacials, in Climate of the Past, 7, 501-509.
Novel methodological approaches in loess research – interrogating biomarkers and compound-specifc stable isotopes
Zech Michael, Zech Roland, Buggle Björn, Zöller Ludwig (2011), Novel methodological approaches in loess research – interrogating biomarkers and compound-specifc stable isotopes, in Eiszeitalter & Gegenwart - Quaternary Science Journal, 60, 170-187.

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
Isotope Meeting Poster 28.08.2013 Bern, Switzerland Zech Roland;
Int. Symposium on Paleopedology Talk given at a conference 10.08.2013 Kursk, Russia Zech Roland;
EGU 2013 Talk given at a conference 07.04.2013 Wien, Austria Zech Roland;
CH-QUAT Meeting 2013 Talk given at a conference 26.01.2013 Basel, Switzerland Zech Roland;
AK Geomorphologie Poster 11.10.2012 Freising, Germany Zech Roland;
Joint European Stable Isotope Users group Meeting Poster 02.09.2012 Leipzig, Germany Zech Roland;
International Summerschool for Paleopedology Talk given at a conference 01.08.2012 Volodarka, Russland, Russia Zech Roland;
Arbeitsgruppe Paläopedologie Talk given at a conference 17.05.2012 Leipzig, Germany Zech Roland;
European Geosciences Union General Assembly 2012 Poster 22.04.2012 Wien, Austria Zech Roland;
Workshop Bobingen Talk given at a conference 20.04.2012 Bobingen, Germany Zech Roland;
AK Hochgebirge Talk given at a conference 11.02.2012 Muenchen, Germany Zech Roland;
Treffen des AK Permafrost Talk given at a conference 31.10.2011 Rolandseck, Germany, Germany Zech Roland;
Annual Meeting of the German Association of Stable Isotope Research Talk given at a conference 10.10.2011 Villigen, Switzerland Zech Roland;
Jahrestagung des AK Geomorphologie Talk given at a conference 28.09.2011 Leipzig, Germany, Germany Zech Roland;
International Meeting on Organic Geochemistry Poster 18.09.2011 Interlaken, Switzerland, Switzerland Zech Roland;
International Palaeopedology and Soil Geography Conference Talk given at a conference 28.07.2011 Hohenheim, Germany, Germany Zech Roland;
INQUA 2011 Poster 21.07.2011 Bern, Switzerland Zech Roland;
Jahrestagung der Arbeitsgemeinschaft Paläopedologie Talk given at a conference 02.06.2011 Bayreuth, Deutschland, Germany Zech Roland;


Awards

Title Year
Vortragspreis des AK Geomorphologie 2011
Young Scientists Oral Presentation Award, IUSS Commission on Paleopedology 2011

Associated projects

Number Title Start Funding scheme
150590 Ice Age Siberia - Climate, Landscape and Carbon Sequestration 01.04.2014 SNSF Professorships
119492 Quantitative temperature and precipitation reconstruction from loess-paleosol sequences based on lipid biomarker and compound-specific isotope analyses 01.03.2008 Fellowships for advanced researchers
141579 Lipid biomarker analyses in the loess section Igetei, Siberia 01.02.2012 International short research visits

Abstract

Loess-paleosol sequences (LPS) are unique terrestrial archives for Quaternary (~2 Ma) climate and environmental reconstruction. By analogy to the findings from the famous Chinese Loess Plateau, LPS in Europe, Central Asia and Siberia have often been interpreted to document the succession of warm, humid interglacials and cold, arid glacials. However, the value of LPS has not yet been fully exploited, in part because quantitative paleoclimatic information, particularly regarding temperature and precipitation, has been difficult to obtain. Recent innovations in organic biogeochemistry made possible by methodological developments are poised to catalyze a new era of terrestrial paleoclimate research.The aim of the proposed research project was to reconstruct climate and environmental changes from key LPS in southeast Europe, Central Asia, southern and northern Siberia applying various novel molecular proxies:(i) Lipid biomarkers derived from soil bacteria (GDGTs),(ii) leaf wax biomarkers (long-chain n-alkanes and fatty acids), and(iii) compound-specific deuterium analyses on the leaf waxes. Results: Leaf wax biomarkers in the LPS Darai Kalon (Tajikistan), Igetei, Kurtak, and Iskitim (Siberia) indicate a variable, but constant presence of deciduous trees during the last glacial. The general notion of pronounced glacial aridity and predominance of grasses over trees is not fully supported. Mean annual temperatures (MAT) inferred from GDGT lipids don’t reflect the expected glacial-interglacial changes, and GDGTs should be interpreted with caution. Compound-specific deuterium analyses reveal more depleted values during glacials and more enriched values during interglacials, documenting the dominant temperature control and the great potential of these analyses for climate reconstructions in Siberia. Topsoil samples corroborate the usefulness of leaf wax biomarkers for the reconstruction of past vegetation, and compound-specific radiocarbon dating showed the stratigraphic integrity of these compounds, i.e. no significant post-sedimentary overprint related to roots or microorganisms. The combination of compound-specific deuterium and oxygen isotope analyses has great potential for quantitative paleoclimatic reconstructions in LPS and lacustrine sediments.
-