Policies using carbon capture and storage in soil are impractical and costly say experts

Jul 16, 2013

(Phys.org) —Although recommended in the Coalition's Direct Action Plan and the Carbon Farming Initiative, offsetting greenhouse gas emissions by increasing carbon storage in Australian agricultural soils is not likely to be effective, say experts from the University of Melbourne.

A team of researchers from the Melbourne School of Land and Environment have analysed 56 papers to understand the effects of agricultural management practices on soil carbon sequestration in Australia.

Study author Professor Rick Roush, Dean of the Melbourne School of Land and Environment, said the potential for increased in Australian was technically and economically very limited.

The analysis is published this week in Nature's Scientific Reports and authored by University of Melbourne researchers Professor Roush, Professor Deli Chen, Shu Kee (Raymond) Lam and Professor Arvin Mosier, also based at the University of Florida.

"We reviewed and analysed a large group of studies including 172 direct comparisons for the effects of , 116 for residue retention, 83 for the use of pasture and 64 for increased application of ," Professor Roush said.

Using the findings of these previous studies, the team then ran calculations based on the 100 million hectares of managed cropland and modified pasture in Australia, assuming 100 percent take-up of the improved practices, and without their potential for increased emissions of methane from and nitrous oxide from additional nitrogen fertilizer.

"Our analysis showed that these strategies would result in only 53.3 million tonnes of CO2 equivalent sequestered in soil and would therefore not meet the 85 million tonnes targeted in the Coalition's Direct Action Plan," Professor Roush said.

Professor Chen added that even at the relatively high of $23/tonne, all practical soil management practices lost at least $3 per hectare per year. Under normal cropping practices, farmers would need about $36 per hectare to break even on carbon payments. This, along with the restrictions that the carbon must remain sequestered 100 years, limits the viability of the Carbon Farming Initiative.

"Increasing soil carbon is good for fertility and productivity of soils, so has long been a goal of cropping, even though the financial benefits are hard to calculate," Professor Chen said.

"Even when nitrogen fertilizer was used to increase crop growth and subsequent soil carbon, the costs of the extra fertilizer use generated a financial loss across all systems even assuming that you can keep the carbon in the ground despite drought, and changing land ownership and practices."

Explore further: Scientists discover coral's best defender against an army of sea stars

More information: www.nature.com/srep/2013/13071… /full/srep02179.html

add to favorites email to friend print save as pdf

Related Stories

Greenhouse gases from farmland underestimated

Apr 02, 2013

(Phys.org)—Changes in agricultural practices could reduce soil emissions of the greenhouse gas nitrous oxide and the atmospheric pollutant nitric oxide, according to a new study by scientists at the University of California, ...

Biochar reduces nasty nitrous oxide emissions on farms

Apr 29, 2013

(Phys.org) —In the quest to decrease the world's greenhouse gases, Cornell scientists have discovered that biochar – a charcoal-like substance – reduces the nemesis nitrous oxide from agricultural soil ...

Carbon buried deep in ancient soils

Jun 21, 2013

(Phys.org) —The unearthing of significant carbon stores in deep soils by scientists from the UK and Australia has substantial implications for climate change activities globally.

Recommended for you

Rating the planet's oceans

1 hour ago

The most comprehensive assessment conducted by the Ocean Health Index rates the Earth's oceans at 67 out of 100 in overall health. In addition, for the first time, the report assessed the Antarctic and the ...

Feds to unveil cleanup plan for nuke waste dump

4 hours ago

After nearly eight months, the U.S. Department of Energy has formalized a plan for cleaning up the federal government's troubled nuclear waste dump in southeastern New Mexico.

Climate change affecting species

6 hours ago

The Global Change and Sustainability Research Institute (GCSRI) and the Wits Rural Facility (WRF) hosted a top climate change scientist, Professor Camille Parmesan, who delivered a talk to staff, students ...

User comments : 0