Holocene vegetation and climate variability in North Pre-Baikal region, East Siberia, Russia

The paper presents the first reconstructions of vegetation and climate of the North Pre-Baikal region covering the last 9000 years based on detailed pollen records from peatlands. Recorded major changes in pollen spectra and vegetation are demonstrated to correlate with large-scale climatic events, such as the regional climatic optimum ca. 9000-6800 BP, termination of the optimum ca. 7000-6500 BP, and Neoglacial cooling culminated ca. 3000-2000 BP. The most warm and wet climate existed about 9000-6800 BP, the interval being referred to as the regional Holocene optimum. At that time, vegetation was dominated by dark coniferous forests of Abies sibirica, Picea obovata with Pinus sibirica. Since 6800 BP, the dark coniferous forests gave way to light coniferous ones (Pinus sylvestris and Larix) in response to gradual decrease of precipitation and summer temperatures to today's values, agreeing well with earlier obtained data. The new records suggest the cold boreal plant communities are highly sensitive to climatic changes. Detailed dating of the sequences would facilitate inter- and intra-regional correlations of the obtained records and reconstructed events.