Changing distribution patterns of selected conifers in the Quaternary of Europe caused by climatic variations

Abstract

Extreme climatic variations in the Quaternary of Europe did not only lead to an intense reduction of plant diversity, but also to significant changes in plant distribution. It is the aim of this work to exemplary investigate distributional changes of selected conifers that were exposed to different climatic impact during the last glacial-interglacial cycle using combined palaeobotanical datasets.<br /> Within the scope of this PhD project, areal changes of two selected conifer species, Abies alba and Picea abies, are investigated in the course of different warm phases of the last glacial-interglacial cycle (Eemian, Brørup, Odderade and Holocene) and are compared with recent phylogeographical datasets to achieve a better understanding of chorology dynamics. The two species were chosen for this study, because they are widely distributed within Europe and moreover clearly respond to climatic changes. The aim is to locate glacial refugia of the two taxa in the respective periods as well as the reconstruction of potential migration routes and spread of fir and spruce during the warm stages of the investigated time span (126000 years to date).<br /> The presented palaeobotanical reconstructions are based on both, macrofossil remains and pollen data. Synoptic studies of plant macrofossils provide independent tests of inferences from synoptic maps of pollen data, an approach the success of which is described and discussed for eastern North America (Jackson et al. 1997). Combined fossil datasets provide a more robust basis for locating glacial refugia and reconstructing the postglacial spread of the particular plant species.<br /> Furthermore the present study also includes available phylogeographic datasets. Palaeobotanical data and results of molecular genetic investigations are compared in respect of the vegetational history of Abies and Picea.