More hazard-reduction burns not the answer, experts warn
Prime Minister Scott Morrison wants to see more action on land clearing and hazard-reduction burns, but experts warn burns are ineffective against extreme fires such as the destructive blazes seen this summer.
They also say Australia is carrying out more prescribed burning than in previous decades and to do much more would lead to heavy smoke affecting communities throughout winter.
But Associate Professor Philip Zylstra, from Wollongong University's Centre for Sustainable Ecosystem Solutions, said fuel loads in forests, and state government management, were not responsible for the catastrophic fire season.
"I think that for the federal government to say there needs to be a focus on hazard-reduction burning at this stage appears to be passing the buck to the states," he said.
"The reality is we are at a peak of prescribed burning by state agencies. More has been done in the past decade than in many, many decades."
NSW Environment Minister Matt Kean said there were 960,000 hectares burnt for hazard reduction last year, while the previous highest yearly total since 2000 was 260,000.
Professor Zylstra said a vast increase to the current hazard reduction effort would blanket cities and towns with smoke over winter and create "huge risks" of accidental property damage and even death.
Philip Gibbons, an associate professor at the Fenner School for Environment and Society at the Australian National University, said recent fires in several regions across the country were not halted by cleared farm paddocks, which showed broadscale land clearing was not an effective management technique.
"Fires have burned through rural land which has a much lower fuel load than a hazard-burn area, but that didn't stop fires."
Professor Gibbons said studies showed hazard-reduction burns weren't effective at halting fires and policy that focused on them could push states to set minimum-hectare-burned targets.
Victoria's fire managers have already shifted from an annual hectare target, which was set after the Black Saturday royal commission, to a more strategic approach.
A 2010 study from Wollongong University, The Effect of Fuel Age on the Spread of Fire in Sclerophyll Forest in the Sydney Region, found there was only a 10 per cent chance a fire would be stopped by a hazard-reduction burn. It said road barriers were most effective at halting fires.
"This summer's fires have burnt though many areas that had hazard-reduction burning. They can help control fires in moderate weather conditions, but in severe conditions it might just help reduce the severity," he said.
Cleared buffer zones in the bush within 40 metres of houses reduced house losses by an average of 43 per cent on Black Saturday, Professor Gibbons' study found. But he said no one technique was a solution."If there was a silver bullet on bushfires we'd have found it by now, after the 51 inquiries since 1939."
Associate Professor Trent Penman, from the University of Melbourne bushfire behaviour and management group, said "broader thinking" was needed and "blindly putting money into prescribed burning won't stop the problem".
He said states hadn't "dropped the ball at all" on hazard-reduction burning, and they were "working harder and smarter than they have in the past", particularly since the royal commission into Black Saturday.disallowed/politics/federal/more-hazard-reduction-burns-not-the-answer-experts-warn-20200106-p53p8i.htmlRaider
