Dirt

National Geographic’s Charles Mann has an extensive September cover story on soil.  It’s a long read and this is just my quick synopsis, but it’s a fascinating topic, or at least I thought it was:

Journalists sometimes describe unsexy subjects as MEGO: My eyes glaze over. Alas, soil degradation is the essence of MEGO. Nonetheless, the stakes—and the opportunities—could hardly be higher, says Rattan Lal, a prominent soil scientist at Ohio State University. Researchers and ordinary farmers around the world are finding that even devastated soils can be restored. The payoff, Lal says, is the chance not only to fight hunger but also to attack problems like water scarcity and even global warming. Indeed, some researchers believe that global warming can be slowed significantly by using vast stores of carbon to reengineer the world’s bad soils. “Political stability, environmental quality, hunger, and poverty all have the same root,” Lal says. “In the long run, the solution to each is restoring the most basic of all resources, the soil.”

Mann outlines what can go wrong when we don’t spend time restoring our soil, with stories such the Chinese village of Zuitou, where farmers were exorted to plant on steep eroding slopes

After talking to Zhang Liubao in Zuitou, I watched one of his neighbors pulling turnips from a field so steep that he could barely stand on it. Every time he yanked out a plant, a little wave of soil rolled downhill past his feet.

But there are also hope stories such as from the Sahel, which stretches across Niger and other African nations, where small local farmers are slowly organically restoring recently dead soil.

The carbon sequestration process of good soil means that soil management has a crucial role to play in climate change.

Rough calculations show that “the amount of carbon we can put into the soil is staggering,” Woods says. Last year Cornell University soil scientist Johannes Lehmann estimated in Nature that simply converting residues from commercial forestry, fallow farm fields, and annual crops to charcoal could compensate for about a third of U.S. fossil-fuel emissions. Indeed, Lehmann and two colleagues have argued that humankind’s use of fossil fuels worldwide could be wholly offset by storing carbon in terra preta nova.

Towards the end of his article Mann talks though about the same soil degradation in wealthy European and North American countries:

The ultimate reason that compaction continues to afflict rich nations is the same reason that other forms of soil degradation afflict poor ones: Political and economic institutions are not set up to pay attention to soils. The Chinese officials who are rewarded for getting trees planted without concern about their survival are little different from the farmers in the Midwest who continue to use huge harvesters because they can’t afford the labor to run several smaller machines…

When I told this story over the phone to David Montgomery, the University of Washington geologist, I could almost hear him shaking his head. “With eight billion people, we’re going to have to start getting interested in soil,” he said. “We’re simply not going to be able to keep treating it like dirt.”

Maybe we need to spend more time crouching down with our heads at our feet level so see that is going on down here?

frog says

6 Responses to “Dirt”

  1. tvhe Says:

    Indeed - it was a very good article

  2. Mr Dennis Says:

    Posters from Lincoln University Soils labs:
    “Don’t treat soil like dirt”
    “Some countries have oil, New Zealand has soil”

  3. StephenR Says:

    Science labs are always great places for terrible jokes…

  4. joy Says:

    I have no doubt this need to value and to improve our soils is correct. From where else comes the huge range of human food, except from the ocean. And the timber for building purposes?

    This constantrain, day after day and frequently heavy, in our region, is exceptional. In 6 decades I can recall only 2 other winters that come close. Then the chance of another drought is high. The mud turns to concret and fragile seedlings die.

    To me, these extremes of weather indicate how fragile our ecosystem is, and how difficult it is to grow food, go fishing, plant and grow trees when the extreme elements are against us.

  5. kiwinuke Says:

    New Zealand organic and biodynamic farm adviser, Peter Proctor, has become well known of late for his pioneering work reversing soil degradation in India by introducing Indian farmers to biodynamic-organic farming methods over the past 15 years.

    He claims that although the agricultural “green” revolution in India in the 1960s was initially very successful in raising yields it has bequeathed a legacy of soil degradation, falling productivity, increased fertiliser, pesticide and fungicide requirements and loss of soil’s water holding capacity (as soil humus levels have declined).

    This latter effect has, apparently, translated into the need for regular irrigation which (after 40 years of this approach) has contributed to serious water shortages, alarming drops in the level of ground water and a shortage in many areas of “sweet”water. Many farmers have, consequently, been irrigating with brackish (salty) water, further damaging soil productivity.

    For more background on Peter’s work in India see the link below:

    http://prometheus.co.nz/news/environmental-news/composting-guru/

    or order a copy of the award winning DVD of his work at http://www.howtosavetheworld.co.nz

  6. michaela Says:

    Steffan Browning has been using his articles in “Organics” to advocate for using soil building as a major method of sequestering carbon dioxide. Importantly he makes the point that using wood waste as a biofuels source will deplete the soil by removing the very materials that build soil.

    Also, the Indian state of Kerala has an official state policy position on organic farming. I’ve lost my link but Google on to find the statement.

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