Holocene palaeoenvironmental changes in southern France: a palaeobotanical study of travertine at St-Antonin, Bouches-du-Rhône

Abstract

Travertines are carbonate deposits formed generally during temperate climatic periods. They usually present a succession of travertinous units and detrital sedimentary levels containing leaf impressions and charcoal, respectively. The travertine of St-Antonin was formed during the Holocence in accordance with this model; snail shells and archaeological material have also been preserved, essentially in detrital levels. An interdisciplinary investigation combining two palaeobotanical approaches (identification of leaf imprints and charred wood) has been carried out to identify vegetation changes, at a local or microregional scale during the travertine formation. Our results were compared with those of previous malacological, geomorphological and archaeological studies. The Preboreal and Boreal sequence of the travertine shows evidence of a reduction of the riverside vegetation correlated with the establishment of a mesophilous vegetation dominated by the pubescent oak (Quercus pubescens). During the Boreal–Atlantic transition, the vegetation structure changed slightly under anthropogenic influence. From the Atlantic to the first part of the Subboreal, vegetation seems to have been profoundly affected by intensive human exploitation. This process has broken up the forested area into different plant communities and favoured the dominance of heliophilous and thermophilous species.