Save the Forests: they are crucial to reducing CO2
This is the call to arms which we get from Professor Brendan Mackey, Professor of Environmental Science at the ANU, in the Opinion Section of the Melbourne’s The Age of August 7, 2007. The heading was followed by a sub-heading which makes the unequivocal assertion that “Stopping Logging Will Help Solve the Global Warming Problem”.
He gives us a farrago of nonsense about the capability of the world’s forests in turning back the tide of man-made CO2 emissions, provided mankind will but leave those forests alone, without fire protection, unmanaged, un-logged, unharvested, and un-regenerated.
He focuses on Tasmania, and complains about the recent Labor endorsement of the status quo, wherein the Forest Management Agency (Forestry Tasmania) manages Tasmania’s public forests on Multiple Use and Sustainable bases.
On August 1st, Jon Faine who conducts ABC’s popular morning talkback radio programme, anticipated the doomsday scenario of Prof. Mackey concerning Tasmania and CO2 emissions. In an interview with Kevin Rudd on Labor policy, he accused Rudd of propounding a contradictory policy – on the one hand supporting the Government’s stand against Global Warming, and on the other hand commending the forestry status quo in Tasmania.
Professor Mackey and Jon Faine have acquired the same mindset, most likely from such sources as the Greens and the Wilderness Society, with all the accompanying anti-forestry baggage.
I will endeavour to tease out some of the falsehoods embedded in the Mackey article.
These are my counter-arguments:
(1) Tasmanian land-use statistics, present and past, indicate that today’s forest boundaries embrace land which stands at 66% of the hectares of forest that existed in 1803. Virtually no forest diminution occurred in the 20th century or later
(2) Furthermore, within Tasmania’s late 20th and early 21st centuries we have seen a prodigious area of Public Forest landscape dedicated as National Parks, Wilderness, Valleys of the Giants, so-called “Old Growth Forests”, Cool Temperate Rainforests, and “Forests of High ConservationValue”, also forests with romantic-sounding names, like “Tarkine”. These areas have been excluded from timber utilization in perpetuity.
(3) These swashbuckling logging exclusions occurred under the auspices of the Helsham Enquiry , the RFA Agreement, Tasmanian Community Forest Agreement 2005, and the 2004 pre-Federal Election horse-trading between Howard, Latham & Paul Lennon . This all happened within the span of a couple of decades. The Forest Industries Association of Tasmania has produced a set of progress maps which show the cumulative extent of reservations, as percentages of total forest. The cumulative % figures are : 1982 – 14%, 1992 – 21%, 2001 – 40%, 2006 – 47%.
Considering the situation on mainland Australia :
(4) If Prof.Mackey is advocating a vast Australia-wide plantation programme, as a supplement to the “saved” native forest, where is the productive land to be found? From compulsorily acquired farmland? If so, has he studied the problems of agricultural macro-economics on the national scale?
(5) Prof. Mackey claims that one hectare of mature, tall,wet forest can store the equivalent of 5,500 tonnes of CO2. This seems an extraordinarily large figure, and takes a lot of believing., especially as he blithely tosses it into the ring seemingly as an Australia-wide average. Probably he has this figure embedded in one or more published peer-reviewed “scientific” papers. If so, one would be interested to see how such an enormous figure matches up with the fact that cool temperate rain forest with a tall eucalypt overstory is seriously atypical of Australia’s forest landscapes. The land occupied by our overall forests is generally much less propitious to biomass production than his model. Low and unreliable rainfall( less than 800 mm), shallow and infertile soils (less than one metre depth) and low productivity are the norm. He further confuses the lay community by comparing all this with 1300 cars emitting exhaust fumes over one year, presumably continuously.
(6) Has Dr Mackey compiled a stratified map of Australian forests and potential forest areas, giving himself guidance in factoring hectares and biomass productivity classes into his computations? That would seem to be a sine qua non, to an expert on this subject.
(7) He does not appear to give any credit to the foresters of our country in their pursuit of Multiple Use and Sustainability. To him, their mission in life is simply to flog woodchips off to Japan.
(8) He manages to convey to us that the diminution of a forest is a greenhouse crime, but to do so with the alleged objective of producing pulpwood or woodchips would seem to be infinitely more reprehensible than any other usage. This gratuitous and unfavourable mention of woodchips divulges his covert philosophical linkages with green activist groups.
(9) In his baseless conviction that UNDISTURBED Australian forests are the answer to Australia’s alleged greenhouse problem, Prof. Mackey has lost the ecological plot and fails to grasp the myriad of complexities, constraints , limitations , roadblocks, perils , even stubbornness of Nature,which stand in the way of his masterly “green solution”.
Any forester worth his or her salt, is familiar with the manner in which a tree or forest stand passes through its life cycle (or in forester’s jargon, it’s rotation). Here are the stages in the cycle, starting from the initiation of an Australian afforestation event (natural or artificial), assuming eucalypts, and focussing on biomass (carbon) accumulation :
a) Juvenile phase – insignificant biomass production, grading through to significant and accelerating.
b) Sapling/ Pole phase – rapid growth in height volume and carbon content
c) Middle Age phase – maximum rate of growth in biomass
d) Mature phase – plateau effect, extending over decades.
e) Overmature phase – rate of growth of biomass in decline, verging on the static
f)Senescent phase- absolutely static growth, and tree health now a consideration, plus attack by insect and fungal parasites and saprophytes, leading inevitably to the forest giving up its store of organic matter to the atmosphere as CO2.
g) The first symptom of this disintegration of the forest overstory is the progressive shedding of the dead branches. The last stage is gravity consigning the mortal remains to the forest floor, to join the invertebrates, microbes, and of course the CO2 stream.
h) The question arises – what does Nature have in store for this “residual” forest area, which will have bitterly disappointed Professor Mackey by not retaining its carbon store and forest cover for more than a miserable couple of hundred years. No mention of the word “PERPETUITY” anywhere . That concept seems to be the preserve of Foresters !
i) If we search diligently for the evidence of this failure of our forests to perform to Prof. Mackey’s greenhouse aspirations, we could find the above ecological drama playing itself out in its final phase, in some veteran Eucalyptus regnans stands in Victorian Central Highlands, or Tasmania’s Florentine, Styx & Weld Valleys.
Norman Endacott.
(Retired Forester)
Jennifer Marohasy BSc PhD has worked in industry and government. She is currently researching a novel technique for long-range weather forecasting funded by the B. Macfie Family Foundation.