Shhhh, We've Got a Secret: Soil Solves Global Warming, Part 1

In the seven-minute video after the jump, QuantumShift.tv turns its lens to the carbon emissions caused by large-scale farming practices used in growing much of the food in the United States, Canada and the UK. According to the video Soil: The Secret Solution to Global Warming, land farmed organically, using such methods as "no-till" and the planting of winter cover crops, absorbs and holds up to 30% more carbon than conventional agriculture. Converting all US farmland to organic would reduce CO2 emissions by 10%. The UK version of the video states that such a conversion would result in a 20% per year reduction in CO2 emissions (although the on-screen graphic still reads 10%, ostensibly because only the voice-over has been changed from the US version). The extra carbon in the soil also increases food nutrients, which could greatly reduce health care costs. Dig a little deeper after the jump.

The land-based carbon cycle works as plants take CO2 out of the atmosphere and convert it to organic material by photosynthesis. The oxygen in the molecule is released back into the air and the carbon becomes part of the plant's structure and eventually the soil. Plowing churns up this organic matter and introduces oxygen which expedites its decay. That is, the exposed carbon recombines with oxygen and is released into the atmosphere as CO2, a principle greenhouse gas. The organic farming practice of no-till greatly reduces this large-scale break-up of soil by cutting small slits that are just large enough to accommodate the planting of seeds, thereby conserving the amount of carbon stored in the earth. From a policy perspective, it is most accurate and I think effective to refer to such storing as "agricultural carbon sequestration" in opposition to the industrial catch phrase "carbon sequestration" which refers to the business of going to impractical lengths and assuming a high degree of risk to bury CO2 in the earth's crust. According to the USDA, U.S. agricultural soils have lost, on average, about one-third of the carbon they contained before wide-scale cultivation began in the 1800s, but more on that later. The video also points out that less tillage also decreases C02 emissions from farm machinery since the equipment makes fewer runs over the field. Also, the benefits of no-till sequestration are tripled when combined with the planting of winter cover crops which are used in organic farming to maintain a healthy soil.

Much of the data in the video is based on a 27-year comparative study conducted by the Rodale Institute in Pennsylvannia which also dispels the myth that chemical fertilizers are needed to provide better yields. Today I spoke briefly with Dr. Paul Hepperly who's featured in the video in an on-camera interview, and he told me that the data from the study has been taken up by Kyoto Protocol signatories Great Britain, Germany and the Netherlands as a component of their climate roadmaps for reducing atmospheric CO2 levels. Notwithstanding that good news, petitions are available which have the goal of pushing leaders to shift existing agricultural subsidies from conventional to organic farming. Go here to sign for the US, Canada or ROW (rest of world). Via:: QuantumShift.tv

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