Implications of changing fire risk for conservation management

Climate change is altering wildfire regimes globally, with significant consequences for people, ecosystems, and biodiversity. Using spatially explicit simulations across 12 regions in Victoria, Australia, we assessed how climate change and prescribed burning influence fire regimes and the associated impacts on vegetation. We quantify the probability of short-interval wildfires that subsequently impact the amount of vegetation burnt below minimum tolerable fire intervals (TFI).

In the absence of fire management, annual area burnt by wildfire increased in eight regions under future climate conditions, particularly in the far western and eastern parts of the state. Generally, fire frequency increased under future climate in most regions but the predicted change in fire frequency between current and future climate varied significantly. Within regions fire occurrence varied spatially between current and future climate, with some areas experiencing more frequent fire. Prescribed burning had limited impact on annual area burnt under current climate, except in eastern regions where reductions of up to 29.7% were observed. Under future climates, prescribed burning reduced wildfire extent in eastern regions but increased it in many central and western regions. While prescribed burning generally moderated increases in short-interval wildfires, it also contributed to their occurrence in some areas under both current and future climates.

Vegetation burnt below minimum TFI was most extensive in the Grampians, Glenelg, and Macedon Ranges, with protected areas more affected than unprotected ones. Under future climate and management scenarios, these proportions shifted and varied by region and TFI categories. These findings highlight the complex interactions between climate, fire management, and impacts on vegetation communities.