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In Australia, the drivers of precolonial fire regimes remain contentious, with some advocating an anthropogenic-dominated regime, and others highlighting the importance of climate, climatic variability or alternatively some nexus between climate and human activity. Here, we explore the inter-relationships between fire, humans and vegetation using macroscopic charcoal, archaeology and palynology over the last ~5430 cal. year BP from Broughton Island, a small, near-shore island located in eastern Australia. We find a clear link between fire and the reduction of arboreal pollen and rainforest indicators on the island, especially at ~4.0 ka and in the last ~1000 years. Similarities with comparable palaeoenvironmental records of fire in the region and a record of strong El Niño (dry, fire-prone) events supports the contention that climate was a significant influence on the fire regimes of Broughton Island. However, two periods of enhanced fire activity, at ~4000 years BP and ~<600 years BP have weaker links to climate, and perhaps reflect anthropogenic activity. Changes to the fire regime in the last ~600 years corresponds with the earliest evidence of Indigenous archaeology on the island, and coincides with implications that Polynesian people were present in the region. After the mid-Twentieth Century a human-dominated fire regime is also an obvious feature of the reconstructed fire record on Broughton Island. [ABSTRACT FROM AUTHOR]

The local fire history of a coastal swamp catchment in New South Wales was reconstructed using two proxy records of fire: sedimentary macroscopic charcoal and fire-scar analyses of Xanthorrhoea johnsonii. The charcoal analysis provided a record of fire activity spanning the last 2800 years, while the Xanthorrhoea record covered the last approx. 300 years. The ability of each method to accurately record fire events was verified by cross referencing against the recent (post 1968) historic fire record. Fire history was then extrapolated beyond the historic record, to reveal an unprecedented level of fire activity in the last 35 years, which coincides with increased human activity in the area. In the prehistoric period charcoal and fire scars are comparatively rare, which is most parsimoniously ascribed to little fire activity, but perhaps represents skilful fire manipulation, as is often attributed to Aboriginal people. The comparatively minor fluctuations in macroscopic charcoal during the prehistoric period were approximately coeval with previous evidence of late Holocene environmental change in south-eastern Australia, suggesting that fire frequency at the site responded to climatic variability. The longer temporal perspective of this palaeoenvironmental approach provides information for the contemporary management of fire in this conservation reserve. [ABSTRACT FROM AUTHOR]

Summary The concentration and influx of charcoal in a 210Pb-dated sediment core were used to investigate the recent fire history of Jibbon Lagoon in Royal National Park, NSW. Fire events of the recent (historic) past were compared to this record in an attempt to test its sensitivity. Recent fire events were not always reflected in the charcoal results. Nonetheless it can be concluded that since about AD 1930 the area has been characterized by a relatively high frequency of fires. The analysed sediments of the pre-European period contained a low concentration of charcoal, and only one large conflagration appears to have occurred in approximately the last 1600 years. How Aboriginal people used fire in this landscape is still uncertain. However, it is possible that they did not regularly burn the landscape, or if they did, it was in such a way that the delivery of charcoal to the lagoon was minimal. This study thus suggests that the idea of the ubiquitous use of fire by Aboriginal people should be further, and critically, analysed. [ABSTRACT FROM AUTHOR]