Fossil C 4 plant signals in Southeast Atlantic Ocean continental margin sediments indicate climate-dependent vegetation changes on the adjacent continent

This thesis elucidates the significance of distribution patterns and molecular stable carbon isotopic signatures of long-chain n-alkanes and n-alkan-1-ols. They appear to be suitable proxies to trace climate dependent changes in the predominance of C4 or C3 land plants. Leaf waxes of 35 C4 grasses and three C3 grasses were analysed. These investigations revealed that C4 grass waxes have significantly higher compound-specific delta13C values, high contents of n-C31 and n-C33 alkanes and the abundance of the n-C32 alkanol. This characteristic of C4 plants was determined by investigating Southwest African continental margin sediments from nine cores on a North to South transect from the Congo Fan (4 °S) to the Cape Basin (30 °S). Four time slices of the recent geological history, representing two glacial (MIS 2 and 6a) and two interglacial stages (MIS 1 and 5e), were investigated in combination with pollen analyses. The results of the study demonstrate that this combination of pollen data and compound-specific geochemical proxies can be effectively applied in the reconstruction of past continental phytogeographic developments.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Universität Oldenburg

Year

2006

Author dc:creator

• Rommerskirchen, Florian

• [Keine Schlagwörter von Autor/in vergeben.]

Repository record source_url

http://oops.uni-oldenburg.de/95

OAI identifier oai:identifier

oai:oops.uni-oldenburg.de:95