Tracing fuels for fire through time: from Indigenous cultural burning to colonial land management in Australia

Fire has long been a central Earth system process in Australia, yet the influence of human land management on fire regimes over millennial timescales remains to be fully explored. In southeastern Australia, Indigenous cultural burning sustained fine-grained vegetation mosaics, reduced fuel continuity, and buffered ecosystems against extreme fire events for thousands of years. This study integrates palaeoecological and archaeological evidence to evaluate how the disruption of these practices following colonial settlement reshaped fire-vegetation-climate interactions and amplified fire risk.

Using pollen-based land-cover reconstructions, sedimentary charcoal, archaeological demographic models, we reconstruct spatiotemporal patterns of fire activity through deep time, from 125,000 years ago to the post-colonial period. Our analyses reveal that fuel connectivity reached their lowest levels during the Mid to Late Holocene (ca. 6,000 years cal BP), coinciding with intensification of cultural burning. These stable low-fuel mosaics contrast sharply with the rapid fuel build-up that followed colonial suppression of Indigenous burning in the past two centuries.

We further demonstrate that the transition to post-colonial land management, characterised by fire exclusion, pastoral expansion, and vegetation thickening, created conditions that now interact with anthropogenic climate change to elevate the probability and severity of extreme fire events.

By providing long-term baselines for fire regimes, fuel structures, and human–environment feedbacks, our findings highlight how the loss of Indigenous fire stewardship has fundamentally altered fire risk in southeastern Australia. This historical perspective offers crucial insights for contemporary fire mitigation strategies and the re-establishment of resilient, culturally informed land management under a rapidly warming climate. These insights also resonate with fire-prone regions worldwide where the interruption of Indigenous cultural burning has similarly reshaped fuel dynamics and wildfire behaviour, underscoring the global value of revitalising Indigenous fire stewardship.