Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
https://doi.org/10.5194/bg-2017-277
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
14 Jul 2017
Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Biogeosciences (BG).
Leaf wax n-alkanes in modern plants and topsoils from eastern Georgia (Caucasus) – implications for reconstructing regional paleovegetation
Marcel Bliedtner1, Imke K. Schäfer1, Roland Zech1,3, and Hans von Suchodoletz2 1Institute of Geography and Oeschger Centre for Climate Change Research, University of Bern, Hallerstrasse 12, CH-3012 Bern, Switzerland
2Institute of Geography, University of Leipzig, Johannisallee 19a, D-04103 Leipzig, Germany
3Institute of Geography, University of Jena, Löbdergraben 32, D-07743 Jena, Germany
Abstract. Long-chain n-alkanes became increasingly used for paleoenvironmental studies during the last years as they have the great potential to reconstruct past changes in vegetation and climate. They mostly originate from leaf waxes of higher terrestrial plants, are relatively resistant against physical and chemical degradation and can thus serve as valuable biomarkers that are preserved in various sedimentary archives for at least millennial timescales. However, before any robust interpretation of the long-chain n-alkane patterns in sedimentary archives, reference samples from modern vegetation and topsoil material should be investigated at a regional scale. Apart from Central and South-Eastern Europe, such systematic regional studies on modern plant and topsoil material are still largely lacking.

To test the potential of leaf wax derived n-alkane patterns for paleoenvironmental studies in the semi-humid to semi-arid southern Caucasus region, we investigated the influence of different vegetation types on the leaf wax n-alkane signal in modern plants and topsoil material (0–5 cm) from eastern Georgia. We sampled (i) sites with grassland that included steppe, cultivated grassland and meadows, and (ii) sites that are dominated by deciduous hornbeam forests.

The n-alkane results show distinct and systematic differences between samples from sites with the different vegetation types: n-alkanes derived from sites with grassland are mainly dominated by C31, while n-alkanes derived from sites with deciduous trees show high abundances of C29. Thus, chain-length ratios allow to discriminate between these two different vegetation types and have a great potential when used for regional paleoenvironmental reconstructions. As degradation of organic matter can affect the leaf wax n-alkane distribution, we further present an updated end-member model that includes our results, accounts for degradation effects and enables semi-quantitative reconstruc-tions of past vegetation changes in the southern Caucasus region.


Citation: Bliedtner, M., Schäfer, I. K., Zech, R., and von Suchodoletz, H.: Leaf wax n-alkanes in modern plants and topsoils from eastern Georgia (Caucasus) – implications for reconstructing regional paleovegetation, Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-277, in review, 2017.
Marcel Bliedtner et al.
Marcel Bliedtner et al.
Marcel Bliedtner et al.

Viewed

Total article views: 258 (including HTML, PDF, and XML)

HTML PDF XML Total Supplement BibTeX EndNote
189 64 5 258 14 1 4

Views and downloads (calculated since 14 Jul 2017)

Cumulative views and downloads (calculated since 14 Jul 2017)

Viewed (geographical distribution)

Total article views: 258 (including HTML, PDF, and XML)

Thereof 257 with geography defined and 1 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 17 Oct 2017
Publications Copernicus
Download
Short summary
In this study, we systematically analyze leaf wax derived n-alkane patterns in eastern Georgia to test their potential for paleoenvironmental reconstructions in the semi-humid to semi-arid southern Caucasus region. We investigated the influence of vegetation types on the leaf wax signal in modern plants and topsoil material. Our results show distinct and systematic differences in the n-alkane patterns between vegetation types and prove their potential for vegetation reconstructions.
In this study, we systematically analyze leaf wax derived n-alkane patterns in eastern Georgia...
Share