Les modélisations du couvert végétal en palynologie

Abstract

Among the most recent developments in palynology, a growing number of studies focuses on quantitative reconstructions of vegetation cover. Indeed, the non-linear relationship observed between the pollen counts and vegetation, mainly due to interspecific differences in pollen production and pollen dispersal, can be corrected through the use of mathematical models such as the Landscape Reconstruction Algorithm, through the use of the REVEALS and LOVE models (Sugita 2007a, b). The REVEALS model outputs, concerning the Holocene pollen data from the Paris basin, yield vegetation cover estimates for the main taxa observed at the regional scale. These results clearly change the ranking of the various taxa in terms of relative proportions in the landscape. Thus, the emphasized proportions obtained for the herbaceous taxa lead to a substantial reassessment of the grasslands areas throughout the whole post-glacial period. Similarly, the results suggest that the influence of agro-pastoral practices on the regional landscape was stronger than previously inferred from pollen counts.

Keywords

• palynology
• quantification
• vegetation cover
• anthropisation modeling