Agricultural land could be the focus of an "economic opportunity of unparalleled scale", according to the Wentworth Group of Concerned Scientists, which has called for a re-write of emissions trading legislation to properly recognise "terrestrial carbon".
In a discussion paper released earlier this week, the Group argues that by focusing on terrestrial carbon sequestration as a solution to climate change, Australia can simultaneously address many of its most pressing environmental challenges.
Terrestrial carbon includes carbon stored in forests, woodlands, swamps, grasslands, farmland, soils, and derivatives like biochar and biofuels.
"We're about to create a multibillion dollar terrestrial carbon market, and that has the potential to radically change our rural landscapes," said Wentworth Group director Peter Cosier.
"We have to maximise the benefits and minimise the consequences."
As the paper puts it: "… carbon economics of the 21st century presents our generation with the opportunity to improve the health of our landscapes and conserve the world's biodiversity, at scales that would have been unimaginable even a few years ago."
In the Group’s view, that will require a substantial re-writing of the Carbon Pollution Reduction Scheme to account for all terrestrial carbon, while protecting against "perverse outcomes", like runaway planting of productive farmland to trees.
Founded in 2002, the Wentworth Group aims to drive innovation in the management of Australia’s natural resources and related policy.
Among its 11 members are Professor Tim Flannery, chair of the Copehagen Climate Council, and Professor David Karoly, co-coordinating lead author on the IPCC.
According to the paper’s introduction, global warming science now regards it as impossible to avoid dangerous climate change solely through emissions reduction. Positive change in the carbon balance can only be achieved if parallel efforts are made to remove greenhouse gases from the atmosphere.
"At a global scale, a 15 per cent increase in the world's terrestrial carbon stock would remove the equivalent of all the carbon pollution emitted from fossil fuels since the beginning of the industrial revolution," the paper says.
"The power of terrestrial carbon to contribute to the climate change solution is profound."
A recent CSIRO study that examined Australia's capacity to sequester terrestrial carbon suggested that carbon-friendly grazing practices could be capable of storing 100 million tonnes of carbon dioxide equivalents per year (Mt Co2-e/yr) for the next 40 years.
However, the biggest opportunity lies with "carbon forestry", including biodiversity plantings and timber plantations, with the potential to sequester 750 Mt CO2-e/yr over 40 years.
Overall, CSIRO estimates that the Australian landscape has the potential to store an additional 1000 Mt CO2-e/yr in soils and vegetation over the next 40-50 years.
"If we could capture just 15pc of this biophysical capacity, it would offset the equivalent of 25pc of Australia's current annual greenhouse emissions for the next 40 years," the Wentworth Group paper said.
However, it added a note of caution on food security.
If CPRS legislation and investment mechanisms are not carefully crafted, the most profitable use of prime agricultural land could become carbon forestry, with a subsequent loss of agricultural productivity.
"ABARE has estimated that if Australia commits to reducing greenhouse gas emissions by 25 per cent by 2020, over 40 million hectares—an area equivalent to 40 per cent of the Murray Darling Basin—could be economically suitable for Kyoto compliant carbon forestry.
"If the new terrestrial carbon economy takes large areas of agricultural land out of production, as has happened recently in the United States when corn was turned into biofuel, or when the European Union set biofuel targets but didn’t ban the clearing of tropical rainforests to produce it, then we risk creating more problems for Australia and the world than we solve."
