Putting carbon back in soil may mitigate climate change

New York

THE last great hope of avoiding catastrophic climate change may lie in a substance so commonplace that we typically ignore it or else walk all over it: the soil beneath our feet.

The Earth possesses five major pools of carbon. Of those pools, the atmosphere is already overloaded with the stuff; the oceans are turning acidic as they become saturated with it; the forests are diminishing; and underground fossil fuel reserves are being emptied. That leaves soil as the most likely repository for immense quantities of carbon.

Now scientists are documenting how sequestering carbon in soil can produce a double dividend: It reduces climate change by extracting carbon from the atmosphere, and it restores the health of degraded soil and increases agricultural yields. Many scientists and farmers believe the emerging understanding of soil's role in climate stability and agricultural productivity will prompt a paradigm shift in agriculture, trigger…