Preliminary environmental reconstructions from late Quaternary pollen and mollusc assemblages at Egg Lagoon, King Island, Bass Strait

A late Quaternary environmental record is currently being developed from Egg Lagoon, King Island, Bass Strait, a site which is geographically well situated to contribute towards a history of the Bass Strait region. Environmental reconstructions are based on a stratigraphic survey and pollen, charcoal and mollusc analyses of sediment core samples. The recorded stratigraphy includes five sedimentary units representing estuarine‐marine, freshwater lake and swamp depositional environments. Amino‐acid racemization analyses of marine shells indicate a greater than last interglacial age for the basal estuarine‐marine unit, while radiocarbon analyses of organic muds and wood suggest that a substantial section of the overlying freshwater lake and swamp facies is beyond the conventional limit for this technique. Local pollen assemblages represent freshwater lake and swamp plant communities that have varied presumably according to water level changes at the site. Regional pollen assemblages represent terrestrial herbaceous communities, believed to have existed under cooler and drier climates than today, and Eucalyptus ‐ and Phyllocladus ‐dom'maied forests and woodlands from periods with greater effective precipitation than at present. A sustained increase in charcoal representation dating from at least 39 000 years before the present may indicate an anthro‐pogenically induced change in the fire regime, consistent with the earliest dates for human occupation in mainland Tasmania.