The latest pleistocene in southwestern Siberia and Kazakhstan

• Published in: Quaternary international Vol. 41; pp. 125 - 134
• Main Authors: Kremenetski, C.V., Tarasov, P.E., Cherkinsky, A.E.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 1997
• ISSN: 1040-6182; 1873-4553
• DOI: 10.1016/S1040-6182(96)00044-4

The fossil pollen record of a lake and a swamp in Kazakhstan have provided the first dated evidence of Late Glacial sedimentation in that area. During the Late Glacial, open spruce Picea obovata Ledeb. forests began to spread along river valleys and over the Kazakhstan hills. Siberian larch, honeysuckle, sea buckthorn, dwarf alder and dwarf birch grew in the Irtish Valley. At that time, both the average January and July temperatures in the northern part of the Kazakhstan hills were at least 2.5–3°C below the present-day values. The greatest depression of the July temperature is estimated for the Semipalatinsk-Irtysh area, at 4.5–5°C; the corresponding figures for January being 2.5–3°C. The amount of rainfall remained approximately at its present level. Existing records fail to identify significant changes in the vegetation and climate at the time of the Late Glacial/Holocene transition between 12,000 and 9500 BP. At the end of Preboreal time, the southern limits of spruce, Siberian silver-fir and larch approached their present positions. During the first half of the Boreal phase, both steppe and open birch forests formed the vegetation in the southern part of the West Siberian Lowland. Dry bunchgrass-wormwood steppe and semi-desert were the main types of vegetation in Kazakhstan. By 6000 BP, pine ( Pinus sylvestris L.) reached its present day southern limit in Kazakhstan.