A Comparison of Charcoal and Archaeological Information to Address the Influences on Holocene Fire Activity in the Sydney Basin

Abstract

The influence of Aboriginal people on fire activity and hence the vegetation of Australia has long been debated. This study aimed to document the local fire activity of the Holocene in the catchment of a small freshwater reed swamp located in the Sydney Basin and to compare this with nearby archaeological evidence; including artefact discard rates and the number of base camps and activity locations used through time. This archaeological evidence was used as an index of human activity through time to assess anthropogenic influences on fire activity. Charcoal (!250 mm) was quantified in a radiocarbon-dated sediment core from Griffith Swamp covering Â6000 calibrated years BP. A substantial increase in fire activity was found from Â3000 years BP and a lesser increase approximately 700 years ago. The change in fire activity at Â3000 years BP was approximately coeval with changes in archaeological evidence from Upper Mangrove Creek, suggesting either greater human presence in the landscape or altered subsistence and land-use strategies. Fire frequency in the catchment of Griffith Swamp peaked at about eight episodes per century, perhaps in response to environmental change that promoted both increased human activity and a higher natural fire frequency. This study provides an extended temporal perspective on fire and humans in this landscape, demonstrating how palaeoecology can provide practical information for the contemporary management of such fire-prone ecosystems.

Resolving the Holocene alluvial record in southeastern Australia using luminescence and radiocarbon techniques

“…These events have been well documented on the neighbouring Goulburn River by Erskine (1994) and on Wollombi Brook by Erskine (1996). A reduction in charcoal accumulation, like that identified for Goochs Swamp by palynological and charcoal abundance studies (Black and Mooney, 2007; Mooney et al ., 2007; Black et al ., 2008), would also contribute to gaps in the radiocarbon alluvial record.…”

“…The most widely applied technique for dating Holocene fluvial deposits is radiocarbon dating of different organic material, depending on abundance. In southeastern Australia, charcoal is abundant due to frequent fire activity over the Holocene (Black and Mooney, 2007; Mooney et al ., 2007) and is favoured for chronological reconstructions. However, the uncertainty associated with dates from sedimentary charcoal is significant (Blong and Gillespie, 1978; Benito, 2003).…”

Nonsynchronous, episodic incision: Evidence of threshold exceedance and complex response as controls of terrace formation

“…Kershaw (1998) and Kershaw et al (2002) reported increased rainfall and seasonality between 7 and 5 ka with conditions becoming cooler and drier between 4 and 2 ka. This is consistent with the warmer and wetter periods of the El Niño-Southern Oscillation (ENSO) dominated climate, which began at~6.1 ka BP (Singh et al, 1981;Dodson, 1994;Black and Mooney, 2007;Mooney et al, 2007;Black et al, 2008). This was a period of variable climatic conditions known as the Holocene climatic optimum (Bryant, 1997;Black et al, 2008).…”

Geographical Fire Research in Australia: Review and Prospects

“…Mooney et al . () argued for the value of palaeoecology in providing practical information for the contemporary management of fire‐prone landscapes. Eriksen et al .…”

“…Muller (2006) proposed a method of constructing chronological fire histories using flowering 'scars' on Austral Grasstrees. Mooney et al (2007) argued for the value of palaeoecology in providing practical information for the contemporary management of fire-prone landscapes. Eriksen et al (2011) advocated a mixed-methods approach to provide insight into complex factors that influence bushfire preparedness that have both tangible policy relevance and analytical depth.…”