
Becoming a 'carbon neutral' livestock business is possible but it takes time unless producers want to simply buy carbon credits, according to Qld-based agricultural consultant Stephen Wiedemann.
At the SA Livestock Consultants annual conference held online last week, he encouraged livestock producers to get on the front foot and understand their on-farm emissions so they can take baseline measurements.
From there they could measure and report these changes to reap environmental dividends.
"Twenty years ago, the carbon market was driven by governments but now it is companies setting net zero emissions, so there is a future in it," he said.
There has been plenty of discussion about offsetting emissions by storing carbon in trees, but Dr Wiedemann said the work of his company, Integrity Ag & Environment, measuring the carbon footprint of several hundred farms had found 'carbon neutral' by this method alone was uncommon.
He said 80 per cent to 95pc of on-farm greenhouse emissions came from the livestock themselves, so altering flock and herd structures and maximising on-farm productivity could help balance the carbon equation.
"We do find some appetite in some producers for more productive yet smaller herds or flocks but, of course, others have business objectives to do the opposite and expand," he said.
Twenty years ago, the carbon market was driven by governments but now it is companies setting net zero emissions, so there is a future in it.
- Stephen Wiedemann
"At least if you are expanding and you are doing it via more productive flocks or herds, you will have lower emissions relative to what you would have."
Emerging feed additives, such as red asparagopsis (red seaweed), which manipulates rumen performance, were also close to commercialisation.
Feeding these products has been shown to reduce methane emissions by as much as 95 per cent in feedlots and Dr Wiedemann expected the use of these additives to spread to grazing systems in three to five years.
In his consults he asks his clients how much area they are willing to dedicate to trees, without losing productivity, because he says as much as 20 per cent of their land could be needed to offset on-farm emissions.
"Not all trees are created equal, with sequestration rates from one tonne of carbon dioxide equivalent per hectare per year to 20t and even more so at those low rates you are talking about a large amount of land," he said.
Achieving small increases in soil organic carbon storage through planting more perennial pastures and practices such as not overgrazing paddocks and removing tillage from the farming system had potentially huge off-setting potential.
A 0.1pc change at a soil depth of 30 centimetres equated to storing about 4t more carbon a hectare.
But Dr Wiedemann said the biggest difficulty was measuring such small changes in the soil.
Adelaide-based company Ziltek is developing a hand-held instrument to be able to quantify soil carbon increases quickly in the paddock.
Ziltek chief scientist Sean Manning, who was another speaker at the Livestock Advisor Update, says they are hoping to adapt their REMSCAN spectrometry machine, which monitors soil remediation in the mining industry, for use in agriculture.
They have undertaken proof of concept studies from 1000 soils collected in the SE of SA that were also assessed in an accredited lab.
Dr Manning says they have found high accuracy levels in the machine for measuring carbon, soil pH and other properties.
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