A new study has found that land-use changes following British colonisation have contributed significantly to Australia’s bushfire crisis by transforming open woodlands into dense forests with greater amounts of combustible vegetation. Researchers say these changes have increased wildfire risks and amplified the effects of climate change.
The study published in the journal Nature conducted by researchers from the University of Melbourne in collaboration with the Gunaikurnai Land and Waters Corporation. The team reconstructed 1,000 years of vegetation changes fire activity and soil erosion in Croajingolong National Park in East Gippsland, one of southeastern Australia’s most fire prone forest regions.
The findings show that colonisation triggered major ecological changes, including hotter fires, a four-fold increase in eucalypt cover, the transformation of open woodland into dense forest and increased soil erosion.
Lead author Professor Michael-Shawn Fletcher from the University of Melbourne said the research highlights the importance of Indigenous land management practices, particularly cultural burning, in reducing wildfire risks.
For thousands of years, Gunaikurnai people used cultural burning to care for the land and maintain much of the landscape as open woodland. According to the researchers, these practices helped manage vegetation and reduce the accumulation of combustible material.
Historical climate records indicate that periods of dangerous fire weather comparable to conditions experienced during the Ash Wednesday and Black Saturday bushfires, also occurred before colonisation. However, the researchers found that the open landscapes maintained through cultural burning were more resilient to catastrophic fires.
Following colonisation traditional land management practices were disrupted, allowing forests to expand and vegetation to thicken. This increased the amount of fuel available to fires, making the landscape more vulnerable to intense wildfires.
Sediment records reveal changes in fire intensity
To reconstruct the region’s fire history, researchers analysed lake sediments containing charcoal and other environmental evidence. Infrared analysis of preserved charcoal helped them estimate past fire temperatures.
The findings indicate that hotter fires emerged before the major increase in eucalypt cover, suggesting that changes in fire regimes helped drive the transformation from open woodland to dense forest.
Researchers said these ecological changes occurred before human driven climate change became a major influence highlighting the lasting impact of colonial era land management on the region’s present day wildfire vulnerability.
Professor Fletcher said discussions about Australia’s bushfire crisis often focus primarily on climate change, while the historical transformation of landscapes receives less attention. The study argues that the accumulation of vegetation over generations has helped create conditions in which climate extremes can trigger more destructive fires.
Indigenous cultural burning seen as key to reducing risks
The research highlights the importance of restoring cultural burning and supporting Traditional Owners in managing their ancestral lands.
Gunaikurnai elder Uncle Russell Mullett said the Gunaikurnai people have a longstanding relationship with fire known as “towera”, as part of their daily life and care for Country.
He warned that failing to manage the land through traditional practices can make it increasingly dangerous for people, animals and plants. He added that scientific research provides important evidence supporting Indigenous led land management initiatives.
The study also challenges the idea that places such as Croajingolong National Park are untouched wilderness. Researchers argue that the forest landscape often regarded as pristine has itself been shaped by historical land-use changes following colonisation.
According to the study understanding these historical changes is essential to developing more effective wildfire management strategies. The researchers conclude that combining scientific evidence with Indigenous knowledge and cultural burning practices could help reduce fuel accumulation, improve landscape resilience and mitigate future bushfire risks.
The findings underline that climate change is not the only factor shaping wildfire danger. Historical land management, vegetation density and the loss of traditional burning practices also influence how severely landscapes respond to extreme fire weather.