A Holocene record of sea level, vegetation, people and fire from western Tasmania, Australia

Abstract

The analysis of a 10 000 calendar year (cal. ka) pollen record on the west coast of Tasmania has revealed a suite of changes that can be related to sea level, fire and people. Fire-promoted moorland has occupied the site for the entire period and challenges the long-held assumption that rainforest dominated the landscape of western Tasmania through the early to mid Holocene. Changes in wetland taxa and the occurrence of benthic marine diatoms indicate a Holocene sea-level high-stand between 6.3 and 5.8 cal. ka. A significant and sustained rise in charcoal concentration occurs after 6 cal. ka, reflecting the combined effects of anthropogenic burning and hydrological changes that were probably modulated by regional climatic forcing. Finally, European colonisation resulted in a significant decrease in charcoal, rapid peat accumulation and a suite of vegetation changes.

The origin and temporal development of an ancient cultural landscape

“…, 2003) and hiatuses have been identified in all moorland peat sections subject to intensive dating (Macphail et al. , 1999; Fletcher & Thomas, 2007a, 2010). Charcoal peaks in the early Holocene in western Tasmania (Fig.…”

Firescape ecology: how topography determines the contrasting distribution of fire and rain forest in the south-west of the Tasmanian Wilderness World Heritage Area

“…Evaluating the efficacy of the alternative stable state model (Jackson, 1968) or the ‘stable fire cycles’ model of Mount (1979) for south‐west Tasmanian landscapes requires datasets with a high temporal resolution (Petraitis & Latham, 1999), which our study of a few fire events and the distribution of rain forests at a single point in time cannot provide. Recent palaeoecological studies have shown that the pattern of lowland vegetation has remained remarkably stable throughout the Holocene (Fletcher & Thomas, 2007, 2010b), with the authors suggesting the apparent resilience of each vegetation community is the result of fire–vegetation feedbacks that were maintained by Aboriginal burning throughout this period (Fletcher & Thomas, 2010a). Unfortunately, the low spatial resolution of these studies precludes any detailed analysis of the role of environmental variables such as topography in influencing this apparent stability.…”

Changes in biomass burning mark the onset of an ENSO-influenced climate regime at 42°S in southwest Tasmania, Australia

“…The cool, wet climate and low bedrock nutrient status results in extreme oligotrophy that reduces primary productivity and results in remarkably slow rates of change in the vegetation of the region (Bowman and Jackson, 1981). Fire is an important ecological agent in southwest Tasmania (Jackson, 1968;Wood and Bowman, 2012) and human occupation for the past 40,000 years has had a major impact on the vegetation landscape (Bowman, 1998;Cosgrove, 1999;Bowman and Wood, 2009;Thomas et al, 2010;Fletcher and Thomas, 2010a;Fletcher et al, 2014aFletcher et al, , 2014b. Treeless pyrophytic vegetation types dominate the landscape (including species of Melaleuca, Leptospermum and Restionaceae and Gymnoschoenus sphaerocephalus) and pyrophobic arboreal communities (rainforest) are restricted by topography and aspect and the protection those afford from fire (Wood et al, 2011).…”