A Comparison of the Environmental Changes of the Post-European Period with those of the Preceding 2000 Years at Lake Keilambete, South-western Victoria

Several parameters representing aspects of vegetation, fire, erosion and lacustrine productivity are investigated to compare the environmental changes of the historic period against those of the last 2000 years at Lake Keilambete in south-western Victoria. The average sedimentation rate post-dating European settlement was found to be c .2.5 times that of the analysed pre-European period and the nature of this sediment is distinctly different. Pollen representation was generally stable prior to the European period, but instability increased subsequently, reflecting the influence of pastoralism and the increase in exotic plant species. An increased concentration (and variability) of carbonised particles in the historic period, despite the faster rate of sedimentation, suggests a complex change in the fire regime of the region. The productivity of Lake Keilambete has varied in the past (e.g. it was elevated between c .1750 and 1250 years BP) but the response to European land use was diminutive. The expression of the quantified sedimentary parameters as average accumulation rates suggests a marked difference in the rate of landscape processes between the pre- and post-contact periods. The environmental change of the post-European period suggests that this landscape was particularly susceptible to the land-use strategies of the European settlers.