Holocene climate and environmental change in high latitudes as recorded by stable isotopes in peat deposits
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
In this thesis, stable carbon and oxygen isotopes in α-cellulose isolated from Sphagnum fuscum moss remains were used as climate proxies. The main focus was to implement the methods in records from high latitude peatlands in the Northern Hemisphere (west-central Canada and north-eastern European Russia), reconstruct palaeoclimate of the studied regions during the Holocene, and evaluate the compatibility of results with other proxy records, especially tree-ring isotope time-series. The variation of stable carbon and oxygen isotope ratios (δ13C, δ18O) in different moss plant components was investigated and differences between untreated plants and α-cellulose extracts were evaluated. The impact of peat decay on the stable isotope proxies was studied by colorimetric and chemical (C/N) methods. Temperature reconstructions were developed based on the statistically significant relationship between δ13C and modern summer temperature records. Wet/dry periods were derived from a combination of δ18O records, macrofossil analysis, and a peat humification record in west-central Canada. A tentative reconstruction of snow depth in north-eastern European Russian tundra and northern taiga was based on δ18O records. The most promising result of the thesis is that stable carbon isotope variability in α-cellulose isolated from Sphagnum fuscum stems can be used to reconstruct and quantify palaeotemperatures several millennia back in time and to reveal both long-term and rapid climate shifts from peat archives.
Place, publisher, year, edition, pages
Stockholm: Department of Physical Geography and Quaternary Geology, Stockholm University , 2012. , 36 p.
Dissertations from the Department of Physical Geography and Quaternary Geology, ISSN 1653-7211 ; 32
stable isotopes, Holocene, subarctic, climate, Sphagnum fuscum
Earth and Related Environmental Sciences
Research subject Quarternary Geology
IdentifiersURN: urn:nbn:se:su:diva-75026ISBN: 978-91-7447-472-5OAI: oai:DiVA.org:su-75026DiVA: diva2:513725
2012-05-11, De Geersalen, Geovetenskapens hus, Svante Arrhenius väg 14, Stockholm, 13:00 (English)
Edwards, Thomas W. D.
Holzkämper, Steffen, DrWastegård, Stefan, ProfessorKuhry, Peter, Professor
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.2012-04-192012-04-032013-09-20Bibliographically approved
List of papers