Farmers have the potential to make a significant contribution in reducing carbon emissions, scientists have revealed.
According to a report in ABC Science, the researchers take the case of Australian farmers and say that they could have a huge impact on greenhouse emissions and the government needs to start seriously encouraging them to sequester carbon in their soils.
Professor Peter Grace of the Queensland University of Technology, an expert on agriculture and greenhouse emissions, estimates that in an ideal situation, more than 900 Megatonnes of CO2 equivalents could be sequestered per annum through improved pasture management.
"It's a very significant amount of carbon," he said.
Grace said that even if only 10% of this amount was achieved, it would result in a significant reduction in Australia's carbon emissions.
According to Grace, though one way to sequester carbon is to grow a bigger crop using more fertilizers, but nitrogen fertilisers produce nitrous oxide, which is a powerful greenhouse gas.
Grace said that any credible scheme would need to include greenhouse gases emitted from animals, fertiliser and tractor use, as well as carbon sequestered by the soil.
But, there is a lack of data and methods to back up such a scheme.
Despite these difficulties, Grace and others think there is still much that can be done to encourage climate-friendly farming practices, while waiting for more data to come in.
John Connor of the Climate Institute determined that the government should give some signal to encourage farmers to sequester carbon.
Connor said that the Australian government should clarify its view of the role of soil carbon offsets and there should be more funding for research into soil carbon management.
Both Grace and Connor argue that even with the uncertainties, it would be possible to begin trialing agricultural emissions trading in a voluntary offset market.
According to Grace, this would help farmers hedge their bets for when agriculture is eventually included in official emissions trading.
Such a scheme could account for the scientific uncertainty in measuring agricultural emissions and sequestration by offering discount credits, he added.
Under this system farmers could, for example, get credit for half the estimated amount of carbon they are sequestering in their soils, with the hope of later using these credits in an official system.
Sequestering carbon should be considered as an investment in adaptation to climate change rather than a money-making mitigation strategy, said Grace.
"Farmers are going to make more money making their farms resilient to climate change than selling soil carbon," he added.