Late Pleistocene vegetation and climate history of Lake Selina, western Tasmania

Analysis of pollen, NRM intensity of sediments, and dating of a 397 cm core from Lake Selina in western Tasmania provides a detailed record of vegetat ion and climate changes for the Last Interglacial-Last Glacial cycle. The v egetation record shows that cool temperate rainforest was present during Is otope Substage 5e and during the Holocene. Wet montane forest and subalpine shrublands dominated the early Last Glacial interstades; subalpine-alpine heathlands and herbfield the stadials. Stages 4-2 mainly had grassland, her bland and heath vegetation. There is close correlation between phases of ma ximum magnetic intensity in the sediments with pollen zones indicating pres ence of herbaceous vegetation. This suggests erosion of the catchment was g reater in the absence of forest or woodland. Climate may have been slightly cooler than present during Substage 5e but the evidence is not definitive. Climate was colder at all times during the Last Glacial Stage until after ca. 14 kyr BP. Maximum temperature depression from present during Stage 2 w as >3.5 degrees C at Lake Selina, but probably as much as 6.5 degrees C in the West Coast Range. Holocene climate was cool and wet. Comparison of the Lake Selina record, with others in western Tasmania and Victoria, indicate that variations in vegetation during the Last Interglacial-Last Glacial cyc le were primarily responses to temperature changes in western Tasmania, and to precipitation changes, particularly summer drought, in western Victoria . (C) 1999 INQUA/Elsevier Science Ltd. All rights reserved.