Spatial vegetation patterns based on palynological records in the loess area between the Dnieper and Odra Rivers during the last interglacial-glacial cycle

摘要

Pollen analysis was done on loess-palaeosol sequences situated to the north of the Carpathians and Sudetes, in the belt characterized by stronger influence of oceanic climate in the West and continental climate in the East. This fact conditioned the occurrence of loess as isolated patches in the West and thick continuous covers in the East, as well as the diversity of natural vegetation cover from deciduous forests and mixed coniferous forests, through forest-steppe to steppe zone. Three loess sites were examined in Poland (Bialy Kosciol, Tarnawce, Polanow Samborzecki), and three in Ukraine (Yezupil, Velyka Andrusivka, Stari Kodaky). Local pollen zones, distinguished in each site, were correlated in order to define the phases of vegetation development from the end of the penultimate glacial, through the Eemian Interglacial to the end of the Vistulian. The obtained picture of vegetation changes supplements the analysis results of organogenic deposits with the description of flora in cold periods when aeolian deposition occurred.rnIn the area under study, the common features of vegetation development were conditioned by a general trend of climatic changes during the last interglacial-glacial cycle. They overlapped with the vegetation changes, expressed by the eastward rising proportion of open landscape elements, which resulted from the increasing continentality of climate. The proportion of trees and shrubs in plant communities during interstadials was also influenced by the proximity of refuges occurring in the Carpathians and Sudetes, and the situation of the examined profiles in river valleys, which were also natural refuges. Other differences in vegetation composition between individual sites resulted from their different meso- and micro-palaeomorphologic situation.