Wednesday, March 31, 2010

Organic Agriculture & Carbon Capture

One of the projects I'm working on is developing a feasibility study for creating benchmarks for carbon sequestration by organic agriculture. This Rodale Institute report gives an overview of organic agriculture's carbon capture. The report notes that organic agriculture could theoretically sequester 40% of current CO2 emissions, if practiced on the globe's 3.5B tillable acres. Organic agriculture is also light on the use of carbon-creating inputs, although a life cycle analysis would need to quantify both the supply chain and downchannel carbon footprint. There are critics of local agriculture movements claiming that local sourcing may not have a lower carbon footprint than non-local production, all things equal, but these claims highlight the need for more measurement.

The mechanism by which organically cultivated soils capture carbons thought to be created is the fostering of fungi that slow decay of organic matter and create carbon-sequestering compounds.

The Rodale Institute's trials are promising::
"During the 1990s, results from the Compost Utilization Trial (CUT) at Rodale Institute—a 10-year study comparing the use of composts, manures and synthetic chemical fertilizer—show that the use of composted manure with crop rotations in organic systems can result in carbon sequestration of up to 2,000 lbs/ac/year. By contrast, fields under standard tillage relying on chemical fertilizers lost almost 300 pounds of carbon per acre per year. Storing—or sequestering—up to 2,000 lbs/ac/year of carbon means that more than 7,000 pounds of carbon dioxide are taken from the air and trapped in that field soil. 
In 2006, U.S. carbon dioxide emissions from fossil fuel combustion were estimated at nearly 6.5 billion tons. If 7000 lb/CO2/ac/year sequestration rate was achieved on all 434 million acres of cropland in the United States, nearly 1.6 billion tons of carbon dioxide would be sequestered per year, mitigating close to one quarter of the country’s total fossil fuel emissions."
The most recent figures {2007} show organic cropland acreage is 4.1M acres or .55% of US total, which would represent 8.8M tons of carbon dioxide sequestered at the rate of 7000 lb/CO2/ac/year. Therefore, current organic production could be sequestering upwards of .14% of 2006 fossil fuel carbons. More precise quantitative measurements of  soil carbons, in combination with the emerging carbon market and the possibility of Obama's cap-and-trade policies passing Congress can provide opportunities for organic farm operators to (1) brand themselves through "carbon sequestering certification" and (2) trading their sequestered carbons.

Canada as a Kyoto Protocol signatory faces penalties of more aggressive targets in the next round, if it doesn't meet its targets. The Harper government has already resigned to that fate. Agricultural sequestering may be a possible pathway for Canada to offset fossil-fuel generated carbons to get closer to the targets.

Future blogs will be on using emerging nanotechnologies to measure soil carbon cost-effectively.

Twitterversion:: Blog on organic agriculture & carbon sequestration. Can measuring CO2 help develop branding & a tradable commodity? @Prof_K

Song:: Robot Science-'The Notion of Backwards Motion'

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