A Quaternary vegetation history of northeastern Queensland from pollen analysis of ODP Site 820

Pollen and charcoal analyses of Ocean Drilling Program (ODP) Site 820 on the continental slope, about 60 to 80 km off the northeastern Queensland coast, provide a continuous record of vegetation through the last 1.5 m.y. that complements and extends Quaternary records from the adjacent mainland. Through most of the record, the gross composition of the vegetation, indicated by pollen of drier and wetter rainforests, open sclerophyll vegetation, freshwater swamps and mangroves, changed little although fluctuations did occur that may relate to cyclical changes in climate and sea level. The replacement of araucarian drier forest by open sclerophyll vegetation and the extinction of a species of Dacrydium may relate to an increase in burning caused by the activities of Aboriginal people. The initiation of this change is dated between ~150 and 100 k.y. ago, well before the date for a similar change in terrestrial records from the region. However, the date is in line with that from Lake George in southeastern Australia and adds substantially to the evidence of a very early time of arrival of aborigines and for their impact on the Australian landscape. -from Authors