Ecologist: Bush fires part of Natures way to rejuvenate
Australia: Ecologist: Bush fires part of Natures way to rejuvenate
6 January 2002
Source and Copyright: The Star Online
CANBERRA: Fires ravaging eastern Australia are part of an ancient cycle of destruction and regeneration that nourishes the continents harsh environment, but wreaks havoc on recent human settlement. New Year is also the annual bush fire season. Each summer, searing heat often tops 40° Celsius and hot winds from the arid interior fan raging firestorms along the continents settled coastal fringe. Many of the 100 blazes now confronting 20,000 firefighters in New South Wales state and menacing Australias largest city of Sydney have been sparked by arsonists. Wicked and mischievous acts, charged state premier Bob Carr. Yet most blazes have ignited naturally and are as much a part of Australias environment as its exotic wildlife and golden beaches.
Fire is neither good nor bad, it simply is, it is a part of the Australian landscapes and has been a part for millions and millions of years, said Graham Freudenberger, an ecologist with the Commonwealth Scientific and Industrial Research Organisation (Csiro). More than 50 million years ago, as Australia slowly decayed into the arid, drought-ridden continent of today, some of the lush rain forest species once covering the landscape evolved into the drought-resistant, fire-dependent plants that now dominate. To hundreds of varieties of eucalyptus, acacia, wattles, banksia trees, grasses and weeds, the scorching lick of naked flame is a welcome trigger that kindles life in their seed pods and generates ash to fertilise Australias bare soils. Unlike most trees which are moisture-laden, eucalyptus trees, which cover 125 million hectares, carry little water. In hot, dry summers, every tree becomes a potential tinderbox. Jim Gould, Csiros bush fire research chief, said eucalyptus trees have a dry fibrous bark, a fuel ladder which fire climbs with such speed and aggression into the forest canopy that trees appear to explode.
It appears like that, but it is just the rapid flare-up of flame, whoosh, it just goes up, said Gould.
Dozens of marsupial and mammal species, kangaroos, wallabies, possums and mice have also become fire-dependent, feeding on the grasses and trees that regenerate quickly after a blaze. Aborigines, who came to Australia more than 40,000 years ago, also adapted to the harsh landscape through the practice of fire-stick farming. They used fire to open up and regenerate bush land areas, replenishing vegetation and attracting the kangaroos,wallabies and reptiles hunted for food. Fire-stick farming is still used in the remote Northern Territory. AP