Clastic and organic material in Younger Dryas profiles: The interaction between abiotic and biotic domains

Abstract

Research into the interaction of abiotic and biotic components of the environment addresses the need to integrate data from these two spheres. The geoarchives of palaeodata contain autochthonous and allochthonous material, both organic and mineral. The present article aims to trace these relationships during the Younger Dryas cooling, being a period of high morphogenetic potential, and to determine the sources of the material in the basins and the determinants of its processes of supply. The research into five sites in Central Poland covered the Younger Dryas sections of infills in biogenic sediment basins and the physical geographical features of their catchments. The sedimentological and palynological record (of selected indicator taxa) was analysed in relation to the surficial geological structure and topography. Aeolian activity played a leading role in the morphogenetic systems of the catchments, regardless of geological structure or the nature of the Younger Dryas plant communities. It was also marked by an increase in pollen concentrations and an increased share of mineral material in limnic-peat sediments. A connection was found between the rejuvenation of the geological substratum and the share of pioneer species, such as juniper, in the vegetation cover. Slope, aeolian and fluvial processes were responsible for the rejuvenation of the substratum, depending on the nature of the catchment.