Fire regimes Frequent and extensive fires in northern Australia are a consequence of the region’s monsoonal climate with its marked summer wet season and long and warm winter dry season. The wet season generates heavy growth of grasses and other herbs, and the trees are continually dropping leaf litter throughout the dry season. This dries out or ‘cures’ during the dry season into tinder-dry, fine fuels for fires. Dry thunderstorms during the build-up and early wet season have always produced lightning. Aboriginal people used fire widely across most of Australia and continue to do so across much of the north. Thus, for thousands of years there has been the combination of annual supplies of dry, fine fuel and ignition sources that can sustain regular, frequent fires. European settlement has caused significant change to the fire patterns of northern Australia in the last century. The challenge for today’s land managers is to work out the optimum mix of fire patterns at the landscape scale—hundreds to thousands of square kilometres—that protect life and property, maintain the productive potential of the land and conserve biodiversity. To do that, we need to understand the factors that determine the fire regimes in the savannas.
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