Plant Responses to a Re-emergence of Cultural Burning in Long-Unburnt, Threatened Temperate Woodlands

Abstract

For tens of thousands of years, Indigenous Peoples have shaped the structure and function of ecosystems through cultural burning, which has many important cultural, ecological, and societal values. In recent years, public interest in cultural burning has increased in response to more severe wildfires globally, and alongside greater calls from Indigenous Peoples for cultural revitalization, as well as generations of Indigenous leadership in advancing community self-determination. This has sparked the development of many new agency-supported cultural burning programs worldwide. However, these programs are often limited by an absence of cross-cultural partnerships and a lack of understanding of how contemporary ecosystems respond to burning. Here, we report the ecological outcomes of an Indigenous-led cultural burning program, delivered by a cross-cultural partnership between Aboriginal communities, ecologists, land managers, and emergency responders. Our ecological study was underpinned by data collected against a before, after, control, impact design in the critically endangered box-gum grassy woodlands of eastern Australia. We provide evidence that cultural burning promoted the establishment of disturbance-sensitive native leguminous plants and graminoids, with positive responses pronounced in high-condition sites. However, exotic plants characterized burning responses where floristic condition was initially low. Our findings demonstrate the marked influence of starting conditions on vegetation responses after burning, which are likely a product of past disturbance. Taken together, the results highlight the potential complexities of reintroducing fire into long-unburnt landscapes that have been highly modified by a long history of western agricultural management. Therefore, post-burning interventions in low-floristic condition sites will be critical to mitigate weed invasion and to promote native plants. Our work demonstrates the value of forming partnerships that unite Indigenous knowledge and western science and management to generate cross-cultural positive outcomes and benefits. These include the generation of a new body of ecological evidence to support the reemergence of cultural burning in southeastern Australia.