Development of the Kubłowo palaeolake, central Poland, during the Eemian Interglacial as against subfossil Cladocera analysis - preliminary results

The results of analysis of Cladocera occurrence in lacustrine sediments from the Kubłowo site have been presented. Lacustrine and peat deposits found there have been previously analyzed for pollen content (depth of 11.1-3.8 m) and represent a longest continuous Eemian-Vistulian succession in central Poland (Roman and Balwierz, 2010). Cladocera analysis was carried out on 25 samples from the depth of 9.20-10.5 m of an Eemian age section. The section consists of fine organic sand, silt with organic matter and gyttja. Identified were 19 species of subfossil Cladocera and five zones of fauna development were distinguished. In the early and mid-Eemian low frequency zooplankton in the palaeolake has been found. Best conditions for zooplankton development occurred in the late Eemian (R PAZ E6, E7). At the end of the Eemian a significant change of climate in a deterioration of environmental conditions and decreased presence of zooplankton has been noted. Cladocera results and the pollen data enable a reconstruction of the climatic and environmental changes in the Kubłowo palaeolake.