Dear Jennifer,
This morning 23rd March, an item on 'AM' the ABC Radio current affairs programme quoted an ARTC (Australian Rail Track Corporation) report as saying that the use of timber sleepers results in 500x the carbon emissions compared to using concrete sleepers.** That report claimed the Australian Greenhouse Office as its source.
I have commented to AM through their web site which unfortunately goes to them and them alone. For your interest the following is a reasonable reproduction of that email.
"Dear Sir,
Your item this morning 23rd March quoted the Australian Greenhouse Office as the source of a statement that the use of timber sleepers produces 500 times the carbon emissions of concrete sleepers. That statement must surely put the credibility of the Greenhouse Office at risk.
Some basic facts:
Fact 1. We should all know that timber contains carbon and concrete does not.
Fact 2. To store 1000kg of carbon in railway sleepers 67kg of carbon will be emmitted in the process. The production of concrete to do the same job emits 430kg of carbon and stores none.
Fact 3. To convert a timber sleeper track to a concrete sleeper track means that all the timber sleepers become an emission. Add that to the emissions of producing the concrete replacements and we have a combined emission of 61.2 tonnes of carbon per km and none in storage.
Fact 4. A natural forest of regrowth and old growth is carbon neutral. That is it is emitting carbon at the same rate it is absorbing it from the atmosphere.
Fact 5. A healthy, sustainably managed, production forest is constantly absorbing more carbon than it emits. At the same time carbon is being stored for the life of its products in service.
Fact 6. By excluding the tribal aboriginal from the river front, open woodlands of River Red Gum have turned into closed forests of tall slim trees. If these forests become National Parks they will still need thinning treatment if they are to support the range of biodiversity that we expect to find.
Fact 7. Forests in National Parks can receive thinning treatment, as is the case in the Box- Ironbark, but the trees must be felled to waste as the product from a National Park cannot be sold.
Yours faithfully
Vic Eddy
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** On October 01, 2006, I blogged'Switch to Concrete Railway Sleepers, Negates Wind Farm Savings' with comment that:
"There is much community concern about global warming and an expectation we will all do our bit to reduce greenhouse gas emissions.
So why did the Australian Rail Track Corporation (ARTC) decide to transfer its annual requirement for 400,000 railway sleepers from timber to concrete?
According to Mark Poynter* this will result in an extra 190,000 tonnes of carbon dioxide emissions per year that could otherwise have been negated by carbon sequestered in forest regrowth and saved by avoiding concrete manufacture.
What a croc!
It has been scientifically proven that logging in souteastern australia dries our forest, creating greater fire risks. Not to mention recent fires in Victoria that escaped from logging coupes following forest 'management'. Get real.
Since when has having a low tolerance of fools been un-australian?
Jonti, you won't find recent research due to the almost complete ideological capture of the funding process by the forces of ignorance and darkness. But the basic elements of species survival tell the true story.
The entire leaf, bud, flower, sap and bark food chains are dependent on three main factors. That is, quality, quantity and continuity of food stocks. And these are dependent on sunlight, water and soil nutrients.
Unlike National Parks, a forest managed for timber production maintains the stand at a stocking density that is below the maximum capacity of the site. And this means that each tree has a larger share of the available moisture, sunlight and nutrients than would be the case in the Park.
This means there is a greater proportion of new leaves as each tree strives to occupy as much space as it can. And these new leaves are more nutritious than a similar tree on similar soil and aspect in an unthinned Park.
And for eucalypt forest this means that the trees have a longer period each year when leaf moisture content is above 65% and leaf protein content is above 1.5%. Once levels fall below these threshholds the tree goes into "asset protection mode" and releases polyphenyls that render the leaves indigestible to all dependent species.
The same story applies to flowers and seeds. The maximum flower, seed and sap production is delivered by vigorously growing early mature trees as they strive to occupy recently created gaps in the canopy.
Studies by Wormington et al have confirmed that highest animal stocking rates were not found on stands with high numbers of "old growth" stems. These trees may provide nest hollows but do not provide sufficient food to sustain a population large enough to use all the hollows provided by old trees, especially when populations are reduced anyway by drought.
The mix of vigorous food trees with a smattering of nest trees that is found in most forests managed for timber production provides a far more contributive habitat with much less dry season mortality and a greater resistance to wildfires.
'wildlife actually prefer managed forests over National Park'
got any science to back up this claim?
Gavin, Why the riverina red gums? Because that is where the expertise exists. Sleeper cutters have worked the forests of the riverina for many generations to provide slepers for Australian railways. These forests have therefore a long history of forest management. Biologically diverse, solar powered and renewable, is it any wonder that timber is the preferred product for sleepers from both environmental and social sustainability perpectives.
Ian mott, how typical of the timber lobby to result to personal insults failing a valid argument. Poor show and un-Australian matey