A new source of fire records, hidden in the sands, gives us a bigger picture of the risks

• For a start, anyone who walks on the forested sand dunes of South-East Queensland will be impressed by the intensity of ant activity at their feet.
• As the ants move materials around their nests, any charcoal from past fires that’s preserved in the sand would be severely disturbed.
• We believe this is a breakthrough that will greatly expand the areas for which we can extract fire histories.
• This new source of fire histories can help us broaden our understanding of fire in Australia.

Why does a new source of fire records matter?

• Many ecosystems are designed not only to survive fire but need burns to survive and thrive.
• In recent years, however, the scale and intensity of bushfires in Australia have increased, culminating in the Black Summer of 2019-20.
• The fires caused long-lasting damage to vegetation and significant loss of both human and animal life and buildings.
• This means we can extract continuous records of past fire regimes from these sediments.

So what did the dune study find?

• Our study focuses on the fire history of the Cooloola Sand Mass between Noosa and Tin Can Bay in South-East Queensland.
• In a 2022 study, we showed there are two distinct phases in the sediment records.
• For the first 1,000 years after the dunes stabilised, frequent but minor flows of sand grains down the front face of the dune slowly built up sediments at the foot of the dune.
• The sand deposited at the base includes the remnants of charcoal from local fires that deposited on the dune’s surface.