This year food shortages, caused in part by the diminishing quantity and quality of the world's soil (see "Dirt Poor"), have led to riots in Asia, Africa, and Latin America. By 2030, when today's toddlers have toddlers of their own, 8.3 billion people will walk the Earth; to feed them, the UN Food and Agriculture Organization estimates, farmers will have to grow almost 30 percent more grain than they do now. Connoisseurs of human fecklessness will appreciate that even as humankind is ratchetting up its demands on soil, we are destroying it faster than ever before. "Taking the long view, we are running out of dirt," says David R. Montgomery, a geologist at the University of Washington in Seattle.
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."
When I met Zhang Liubao in his village in central China last fall, he was whacking the eroded terraces of his farm into shape with a shovel—something he'd been doing after every rain for more than 40 years. In the 1960s, Zhang had been sent to the village of Dazhai, 200 miles to the east, to learn the Dazhai Way—an agricultural system China's leaders believed would transform the nation. In Dazhai, Zhang told me proudly, "China learned everything about how to work the land." Which is true, but not, alas, in the way Zhang intended.
Dazhai is in a geological anomaly called the Loess Plateau. For eon upon eon winds have swept across the deserts to the west, blowing grit and sand into central China. The millennia of dust fall have covered the region with vast heaps of packed silt—loess, geologists call it—some of them hundreds of feet deep. China's Loess Plateau is about the size of France, Belgium, and the Netherlands combined. For centuries the silt piles have been washing away into the Yellow River—a natural process that has exacerbated, thanks to the Dazhai Way, into arguably the worst soil erosion problem in the world.
After floods ravaged Dazhai in 1963, the village's Communist Party secretary refused any aid from the state, instead promising to create a newer, more productive village. Harvests soared, and Beijing sent observers to learn how to replicate Dazhai's methods. What they saw was spade-wielding peasants terracing the loess hills from top to bottom, devoting their rest breaks to reading Mao Zedong's little red book of revolutionary proverbs. Delighted by their fervor, Mao bused thousands of village representatives to the settlement, Zhang among them. The atmosphere was cultlike; one group walked for two weeks just to view the calluses on a Dazhai laborer's hands. Mainly Zhang learned there that China needed him to produce grain from every scrap of land. Slogans, ever present in Maoist China, explained how to do it: Move Hills, Fill Gullies, and Create Plains! Destroy Forests, Open Wastelands! In Agriculture, Learn From Dazhai!