XVI International Botanical Congess

Boring was carried out at the 382m water depth on the center part of Lake Baikal. Pollen analysis of about 1500 samples has been completed. In the interglacial episodes of the Quaternary, arboreal pollen of the subarctic elements was dominated by Pinaceae and Betulaceae, and non-arboreal pollen by plants that indicate a dry climate, such as Ephedra, Chenopodiaceae-Amarunthaceae and Artemisia. In the glacial periods, arboreal pollen was hardly evident. The glacial and interglacial episodes were repeated alternately. Twenty-six glacial-interglacial cycles were confirmed by the core analysis. In the early part of the Quaternary, the intervals of the glacial-interglacial cycles were short, and moreover the glacial periods were short and the interglacial periods long. On the other hand, in the last part of the Quaternary the intervals of glacial-interglacial cycles were long, with long and interglacial periods.