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Could Carbon Farming Help Slow Rising Temperatures?

2017-09-04

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[00:00.00]
  • Earth’s atmosphere is in trouble.
  • [00:03.68]
  • Scientists have linked rising temperatures in Earth’s atmosphere to carbon dioxide and other heat-trapping gases.
  • [00:17.03]
  • When people burn coal or other fossil fuels, it releases carbon dioxide and other gasses into the air, causing the planet to heat up.
  • [00:32.66]
  • Most scientists warn that conditions will get worse unless something is done soon.
  • [00:42.15]
  • Among those trying to find a solution is a volunteer group of scientists and farmers in the United States.
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  • The group, called the Marin Carbon Project, says it has found a proven way to slow the rise in temperatures — and possibly reverse it.
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  • John Wick and his wife own the Nicasio Native Grass Ranch in Marin County, California.
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  • He helped to set up the Marin Carbon Project.
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  • Wick says the project could help save the world from climate change.
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  • He notes that when you stand in the sunshine on a nice day, it is hard to know the Earth is in trouble.
  • [01:40.08]
  • "But when scientists measure it and see the effect of it, and watch the ocean die-off and everything happening, this is scary as hell.
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  • And, then, we have evidence that there might be something that could stop that.
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  • And, then, we had measurement of something that holds promise to actually reverse it."
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  • What is that something he is talking about? Carbon farming.
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  • It uses processed compost to cool the Earth.
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  • The compost comes from cut grass, dead plants or other organic material, which have been shown to improve the soil.
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  • Jeff Creque, an ecologist, developed a theory that processed compost can help control rising temperatures.
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  • He says what we need to do is increase the amount of carbon that agriculture captures.
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  • "Agriculture is the art of moving carbon dioxide from the atmosphere to the vegetation to the soil and, then, back again.
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  • If we can increase the rate of carbon capture and decrease the rate of carbon loss,
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  • we can actually begin to bend that Keeling curve of carbon dioxide in the atmosphere in the other direction, which is what we need to achieve."
  • [03:05.16]
  • Here is how Creque and Wick tested their idea.
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  • In December of 2008, they worked in a test area on Wick’s ranch that had lost carbon from the soil.
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  • They covered the land with one and a quarter centimeters of processed compost.
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  • This area was next to another test area without compost.
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  • Farm animals lived on both plots of land.
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  • The two men wanted to see if the compost-treated land would pull carbon dioxide out of the atmosphere and take in carbon during photosynthesis.
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  • Photosynthesis is the process by which a green plant turns water and carbon dioxide into food when the plant is in the presence of light.
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  • Creque says putting down compost just once on the farmland provided far better results than what they had expected.
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  • He says if you use this method across four million hectares of crop land, large amounts of carbon dioxide would be taken from the atmosphere.
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  • The gas would end up back in the soil and be kept there.
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  • Creque explains that having the carbon dioxide in the ground would help the soil, working “to produce crops and to hold onto water.”
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  • “So, the water implications of this, particularly for a state like California -
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  • but really across the American West and much of the arid regions of the world - increasing soil organic matter what little bit of rain we do get - allows us to hang on to that and make better use of it."
  • [05:14.41]
  • Rancher John Wick is happy with the results of the Marin Carbon Project’s experiments.
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  • He believes carbon farming could make a big difference, if the method was used by many people around the world.
  • [05:33.77]
  • "The implications of this globally are that we can actually cool planet earth, should increase production of food and fiber,
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  • fuel and flora in a way that actually enhances the resources.
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  • So the more you do, the more you can do. It's the most exciting thing ever."
  • [05:50.70]
  • But other people are not so sure about that.
  • [05:54.90]
  • Tom Hedt works for the U.S. government’s Natural Resources Conservation Service (NRCS).
  • [06:03.36]
  • He agrees that compost helps capture carbon in the soil and takes some carbon dioxide out of the air.
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  • But it is just one of many land management practices that NRCS advises to help both the soil and the air.
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  • Others include crop cover, less tilling -- or turning over the soil in between crop planting -- and planting trees and smaller plants.
  • [06:41.90]
  • Hedt says every plot of land is different.
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  • And he says more research needs to be done to know the effectiveness of carbon farming and whether the Marin Carbon Project's findings would be true in larger areas.
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  • "It's an emerging issue. There are some people that are very excited about it. Yeah, there's dangers of taking a few plots and just doing the math.
  • [07:14.22]
  • Multiplication is pretty easy, but the site-by-site prescriptions are much more complicated than that."
  • [07:22.21]
  • He says the findings show enough promise that last year, four-year long field trials were started on a number of range and grasslands throughout California.
  • [07:37.84]
  • sThe 14 trials will run to test the use of compost for carbon farming on different kinds of lands.
  • [07:49.27]
  • I’m Anne Ball.
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