Palaeoenvironmental history of Lake Baikal during the last 23000 years

A sediment core recovered from Lake Baikal was studied in an attempt to elu cidate the palaeoenvironmental history of an intra-continental lake under t he control of last-glacial to post-glacial climatic fluctuations. The lake conditions were characterised by subdued primary production and increased t urbidity conditions during the last glacial maximum. Terrestrial vegetation and the development of soil layers were reduced in the drainage areas. The deglaciation, suggested by increased terrigenous sand influx and biologica l productivity, took place at around 18 000 yr B.P., responding to the incr eased insolation in the Northern Hemisphere high latitude. The onset of wet and warm conditions at ca. 12 000 yr B.P. brought on a maximum of aquatic production and forestal expansion between 7 000 and 6 000 yr B.P. Since 5 0 00 yr B.P., enhanced blooming of diatoms has occurred due to an increased n utrient supply and dissolved silica input into the lake. (C) 2000 Elsevier Science B.V. All rights reserved.