As Australia battles unprecedented fires this year, a debate is under way about what is called "controlled burning" as a means to stop fires spreading.
This involves deliberately starting fires under controlled conditions to clear out low-lying flammable material - sometimes called "prescribed" or "hazard reduction burning".
It is not the same as "back burning", which is done as a last resort to try to slow down an approaching wildfire by stripping the ground of vegetation.
Some politicians in Australia have blamed environmental activism for preventing controlled fires because of their impact on wildlife and fauna.
So what is the truth behind these claims, and does controlled burning really work?
What is being said about controlled burning?
The issue is part of a dispute between the Australian Greens and some other political parties.
The Greens say the major parties need to do more to tackle climate change.
Other politicians have hit back, such as National Party MP Barnaby Joyce who has pointed to what he says is the Greens' opposition to controlled burning.
He thinks the practice should happen more frequently to stop wildfires.
Prime Minister Scott Morrison has become involved, suggesting those "who say they want action on climate change" could be "the same people who don't share the same urgency of dealing with hazard reduction".
■ Australia fires: A very simple guide
■ How do you fight extreme wildfires?
■ What is Australia doing to tackle climate change?
But the Australian Greens - who are not in the government at either national or state level - have made clear they support controlled burning if it is carried out under expert guidance.
The Greens told the BBC that these accusations have been made for some years.
"We've never done anything to prevent or even restrict hazard reduction burning," they said.
How effective is controlled burning?
Swansea University professor Stefan Doerr, an expert in wildfires, believes the practice is less effective than it used to be because of the changed weather conditions which Australia has started to experience.
"It can make a difference for a few years, but I'm doubtful it would make a substantial difference in drought conditions," he said.
He adds that a particular feature of the recent fires in Australia is that they have spread across the crown or top part of the forest - so removing growth at ground level does not make that much difference.
Also the fires have been hot and intense enough to burn through previously-cleared areas, with embers able to travel through the air and ignite other vegetation.
How much controlled burning has there been?
Australian firefighters have a long history of carrying out this type of burning to reduce fire risk. "They are some of the most experienced and well-trained in the world," says Prof Doerr.
Burning to prevent fires is regulated and carried out by state agencies like the relevant fire service, park authority or environment body.
In areas of special environmental value or near heritage sites, national level permission is needed, according to the Department of the Environment and Energy.
An analysis by ABC News shows that while some controlled burning targets in Queensland and New South Wales have been met, others have not because the weather conditions were not right.
The NSW Rural Fire Service report for 2018-19 reveals that although they exceeded targets for reducing fire hazards in parks and forested areas, they fell short of their targets for local government land, privately-owned land and other areas.
Controlled burning can only be done in cooler, damper weather with low wind speeds, to avoid the fire getting out of control.
In 2015, a fire that was started by the Victoria state authorities to burn off hazardous undergrowth ran out of control, destroying four homes and more than 3,000 hectares of farmland and forest.
Some experts argue there needs to be a review of how money is spent dealing with fire risks in a hotter, drier climate.
Rod Keenan, of the University of Melbourne, who has called for a more integrated approach to land management, says: "A lot of resources have gone into extra fire trucks, hoses and getting volunteers. We're not putting sufficient resources into land management."
So while controlled burning does have its place, it is just one part of a broader strategy needed to combat the more extreme fires Australia now faces.
翻譯：隨著澳大利亞今年抗擊史無前例的火災，一場關於“控制燃燒”作為阻止火災蔓延的手段的辯論正在進行。
這包括在受控條件下故意點火，以清除低窪易燃材料——有時稱為“規定的”或“減少危險的燃燒”。
這和“背火”不同，背火是最後一次嘗試通過剝離地面植被來減緩接近的野火。
澳大利亞的一些政客指責環境保護主義阻止了受控火災的發生，因為它們對野生動物和動物造成了影響。
那麼這些說法背後的真相是什麼，控制燃燒真的有效嗎？
關於控制燃燒有什麼說法？
這個問題是澳大利亞綠黨和其他一些政黨之間爭論的一部分。
綠黨說，主要政黨需要做更多的工作來應對氣候變化。
其他政客也進行了反擊，比如國家黨議員巴納比·喬伊斯（Barnaby Joyce），他指出，綠黨反對控制燃燒。
他認為這種做法應該更頻繁地發生以阻止野火。
英國首相斯科特·莫里森（Scott Morrison）也參與其中，他建議那些“說他們希望在氣候變化問題上採取行動”的人可能是“那些在應對減少災害方面沒有同樣緊迫感的人”。
澳大利亞火災：非常簡單的指南
你如何撲滅極端野火？
澳大利亞如何應對氣候變化？
但是澳大利亞的綠黨-他們不在國家或州政府-已經明確表示，他們支持控制燃燒，如果它是在專家指導下進行的。
綠黨告訴BBC，這些指控已經提出了好幾年了。
他們說：“我們從未採取任何措施來防止甚至限制減少危險的燃燒。”。
控制燃燒的效果如何？
斯旺西大學（Swansea University）野火專家斯特凡·多爾（Stefan Doerr）教授認為，由於澳大利亞已經開始經歷氣候條件的變化，這種做法的效果不如過去。
他說：“這可能會在幾年內產生影響，但我懷疑它會在乾旱條件下產生實質性的影響。”。
他補充說，澳大利亞最近發生的火災的一個特別特點是，它們已經蔓延到森林的樹冠或頂部，因此，在地面上消除生長並沒有造成太大的差異。
此外，大火的溫度和強度足以燒穿先前清理過的區域，餘燼能夠穿過空氣並點燃其他植被。
有多少控制燃燒？
澳大利亞消防人員為降低火災風險而進行這種燃燒的歷史悠久。”他們是世界上經驗最豐富、訓練有素的人之一。
為防止火災而燃燒是由國家機構如相關消防部門、公園管理局或環境機構規定和實施的。
環境與能源部稱，在具有特殊環境價值的地區或遺產地附近，需要獲得國家級許可。
美國廣播公司新聞臺的一項分析顯示，雖然昆士蘭和新南威爾士州的一些控制燃燒目標已經實現，但其他一些目標並沒有實現，因為天氣狀況不好。
《新南威爾士州農村消防服務2018-19年報告》顯示，儘管他們超過了公園和森林地區減少火災危險的目標，但他們沒有達到地方政府土地、私有土地和其他地區的目標。
控制燃燒只能在較冷、潮溼、風速較低的天氣進行，以避免火勢失控。
2015年，維多利亞州當局為燒燬危險的灌木叢而引發的火災失控，燒燬了4棟房屋和3000多公頃農田和森林。
一些專家認為，在更炎熱、更乾燥的氣候下，如何處理火災風險，需要重新審視資金的使用方式。
墨爾本大學（University of Melbourne）的羅德·基南（Rod Keenan）呼籲採取更為綜合的土地管理方法，他說：“很多資源已經投入到額外的消防車、水龍帶和志願者中。我們沒有為土地管理投入足夠的資源。”
因此，儘管控制燃燒確實有其作用，但它只是澳大利亞目前面臨的更為極端的火災所需的更廣泛戰略的一部分。
......................................................................................................................................翻譯結束
大火已經燒了這麼久了，還在討論怎樣滅火，怪不得澳大利亞消防員罵那些政客，真是不拿人命當回事。與我國對待這種應急處置相比，真是天差地別，澳大利亞快來中國取經吧。
閱讀更多 尖尖角上 的文章
