Bushfire and our habitat

To: "Andrew Hobbs" <>
Subject: Bushfire and our habitat
From: "Chris Sanderson" <>
Date: Thu, 30 Oct 2008 16:51:45 +1000
Hi Andrew,

Thanks for that response, I hadn't thought about the charcoal issue before,
it's a good point.  One point I'd like to make though, a friend of mine who
used to actually run burns for a state govenernment entity refused to call
them "controlled burns" and instead called them "planned burns".  Says it
all I think.


On Thu, Oct 30, 2008 at 2:25 PM, Andrew Hobbs <>wrote:

> I think the situation is a lot more complicated.
> The obvious one is that in the Australian situation, controlled burns are
> intended to reduce the frequency and extent of major out of control fires.
>  The controlled burns tend to be of lower temperature and hopefully confined
> to the combustion of small dried branches, grass etc. which is likely to be
> recycled back into CO2 fairly quickly anyway by bacteria, fungi etc. Most of
> the large trees containing a large proportion of the carbon shouldn't be
> significantly affected.  Most out of control fires release a much higher
> proportion of the sequestered carbon as they can burn up even large trees.
> So I would suggest that in the medium to long term the use of controlled
> burns could increase the average amount of sequestered carbon.
> This isn't the case in places like Indonesia where the purpose of the fires
> is to remove all the vegetation permanently so that the land can be used for
> agricultural purposes.
> A second factor is how carbon is sequestered.  Most accounts refer to
> sequestration of carbon in the form of 'organic' carbon.  That is carbon in
> organic molecules; in trees, in other vegetation and in the soil.
>  Unfortunately all such 'organic' carbon can and will be relatively easily
> metabolized.  That is, virtually every carbon atom in most trees and other
> vegetation as well as 'organic' carbon in the soil is liable to be recycled
> over some relatively short period of time.  So a mature forest is probably
> close to equilibrium in terms of the degree of carbon sequestration in
> vegetable matter.
> However in the case of fire, particularly in low intensity fires, a
> significant proportion of the vegetation, is converted to charcoal.  In
> general this elemental carbon cannot be metabolized by organisms. The only
> way that this can be remobilized is by oxidation (fire) or other chemical
> means.  This matter is likely to get mixed into the soil column where its
> turnover time would be very long, and could contribute significantly to the
> amount of sequestered carbon in natural areas, although at an admittedly
> rather slow rate.
> In this case fire is required to divert carbon into this long lived store.
>  So controlled fires could be a factor in allowing even relatively mature
> forests to continue to accumulate carbon.
> In fact there have been serious suggestions that wholesale conversion of
> trees or other organic matter into charcoal and then burial would be one way
> of removing significant amounts of carbon from the atmosphere.
> Cheers
> Andrew
> Evan Beaver wrote:
>> Thanks a lot Chris, Rob and Andrew, I knew I could get some reasoned
>> debate from the birders.
>> The argument being presented (this was on Crikey, Tuesday, included
>> below) was that hazard reduction burns should be included in
>> Australia's Greenhouse Accounting. I think this is madness, for the
>> reasons stated in the quote which the author is trying to suggest is
>> some sort of conspiracy.
>> Accounting CO2 released in burns would definitely lead to 'perverse
>> outcomes'. My facetious example is that home owners whose house has
>> burnt to the ground will be handed a bill for the CO2 emitted during
>> the fire. More likely though, is consternation among fire
>> brigades/land managers about the balance between CO2 and hazard
>> reduction. It's just another variable, poorly defined, to throw on top
>> of the management problem we already have.
>> >From a CO2 accounting perspective it's a bit of a silly argument too.
>> The current guidelines state that some CO2 will be released by fires,
>> but some will also be taken up somewhere else at the same time. Seems
>> reasonable, if not a little vague. But then the problem comes from, if
>> you're going to count intentional burns, are we going to add 'wild'
>> bushfires? What about wood heaters? Volcanic eruptions? All of these
>> things emit carbon, but it is short term and 'mostly' part of the
>> natural cycle. Much better to concentrate on our intentional emissions
>> first. Further, are we going to deduct the methane that could have
>> been released had the plant matter rotted anaerobically? Or the CO2
>> for aerobic rotting? Madness, but expect more of it in the next few
>> months.
>> One last thing. Did anyone see '2 In The Top End' when they were
>> looking at Gouldian Finch burns in the north? Very interesting
>> discussion on the pros and cons. It's no longer available on line
>> though.
>> EB
>> Fuel reduction burns not included in Australia's C02 accounting
>> Crikey naturalist Lionel Elmore writes:
>> This spring and the coming autumn will see a three fold increase in
>> Victorian fuel reduction burns, which has a huge impact on Australia's
>> carbon emissions.
>> Nearly 400,000 hectares will be torched this year, and at emissions of
>> 30 to 300 tonnes of CO2 (or more) per hectare, the CO2 emissions from
>> these alone may be from 12 to 120 million tonnes a year. That's more
>> than 10% of Australia's total emissions. This burning includes
>> so-called ecological burns in Victoria which are planned for many
>> National Parks and are supported by botanists.
>> The forest industry, however, does not include these emissions when
>> tallying its contribution to sequestering carbon, which it claims
>> amounts to 23 million tonnes of CO2 pa!
>> In the view of the International Panel for Climate Change and the
>> Australian Greenhouse Office, the CO2 from fires is simply
>> "reabsorbed" when the bush regrows. But common sense dictates that the
>> interruption to carbon storage by fire leaves a sequestration deficit
>> even if the bush recovers its storage capacity after each fire. The
>> CO2 that would have been absorbed annually if the fire had not been
>> lit is effectively an ongoing emission.
>> There are concerns in Victoria regarding the amount of burning and the
>> disregard for the CO2 it produces. An email distributed by
>> conservationists from Gippsland sought comment from botanists,
>> environmentalists and others on the position of the Federal Department
>> of Climate Change. In part, the email stated:
>> Carbon dioxide emissions from fires
>> Carbon dioxide emissions are not reported for the burning of forests
>> or savannas under the UNFCCC or Kyoto Protocol accounting frameworks.
>> Currently, by international agreement, we assume that, for the entire
>> Australian forest and savanna estates, the carbon dioxide emissions
>> released from fires are offset by the carbon sink effects from the
>> regeneration of forests and savannas from previous fires over the long
>> term. In other words, while the emissions from any one bushfire event
>> may be substantial, the net effect of fire events across the entire
>> forest area after regrowth factored into the equation is likely to be
>> neutral in the long term.
>> Many replies to the statement expressed surprise that CO2 emissions
>> were not accounted for, but one stood out. It was carefully written
>> and supported the policy, despite the author's determination to remain
>> anonymous. However, their statement may reveal a "green insider" or a
>> botanist's knowledge of the issue:
>> The accounting rules are not necessarily closely related to what
>> actually happens -- they are more like convenient assumptions at this
>> stage of developing comprehensive accounts. However, they do influence
>> what happens on the ground -- what counts is what people pay attention
>> to.
>> There is very little information about fire and CO2 emissions.
>> >From my perspective, if we think of forests primarily as permanent
>> carbon stores, the impact of fire is usually relatively transient
>> (over periods of decades to centuries). The main objective should be
>> to maintain the ecological integrity of the forest, which in turn
>> maintains the carbon stores in perpetuity (not necessarily at their
>> maximum possible level, but at a level which can be sustained
>> ecologically through variation in climatic and other conditions). If
>> we start managing for carbon alone, all kinds of perverse outcomes
>> will result.
>> The author apparently knows that ecological and fuel reduction burns
>> are a significant source of CO2 emissions, like burning coal, but is
>> determined that they are not seen that way.
>> The most likely "perverse outcome" in the context of this statement
>> would be the end of ecological burning which some argue fosters of
>> biodiversity and helps to combat climate change.
>> There is a school of thought widespread among botanists and foresters
>> that fire is an essential tool in managing the Australian landscape.
>> This view holds that it helps to maintain plant biodiversity.
>> Aboriginal use of fire is frequently quoted, though the evidence cited
>> is often thin and circumstantial at best, especially for forests. But
>> the impact of fire on animals, stream flow and on diminishing rainfall
>> in Australia has been the subject of little research.
>> A perverse outcome of current landscape management has been the recent
>> rapid increase of the use of fire while its impact on CO2 emissions is
>> being actively denied. The views of botanists and foresters have
>> clearly held sway on other academics, the Greens, the CSIRO, the
>> International Panel for Climate Change and the Australian Greenhouse
>> Office.
>> It is illogical that fires in the forests of Southeast Asia are "of
>> concern" to the Australian Government while we impose carbon taxes on
>> the burning of fossil plants (coal), and then deliberately burn the
>> crap out of living plants actively storing carbon in Australian
>> forests.
>> On 10/29/08, Andrew Taylor <> wrote:
>>> On Wed, Oct 29, 2008 at 01:12:35PM +1100, Evan Beaver wrote:
>>> >From my own anecdotal evidence it seems pretty obvious; quite a few
>>>> trees seem to require fire to cast seed, and some need it to
>>>> germinate.
>>> This is a bit of a peeve with me (OK I have lot of peeves) - you hear
>>> this said a lot but if you think about it seems a sub-optimal strategy
>>> for a plant to put all it eggs in one basket and keep  all its seeds in
>>> the canopy.  I gather there is actually there is a spectrum of responses
>>> even among famously fire-adapted groups such as Banskia and Hakeas.
>>> Few species completely retain seeds - most release at least some seeds
>>> between fires (google serotiny).  I believe seed dormancy is similar in
>>> that
>>> most plants which have seeds which lie dormant until a fire (germination
>>> triggered by heat or smoke) also produce at least some seeds which
>>> germinate inter-fire.  As fire plays a large role in reproduction in many
>>> Australian plants, I guess its more pedantry than anything else though.
>>> Rob Whelan who has doen a lot of work on fire ecology at Barren Grounds
>>> and other areas around Sydney has a book which I've been meaning to buy &
>>> read:
>>> I'd agree with a lot Chris said.  My personal opinion is that fire
>>> management goals are often so vague, incoherent and/or unquantifiable
>>> that the limitation of our knowledge don't matter.
>>> Andrew
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