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| U N I V E R S E M A G A Z I N E - F A L L 1 9 9 7 | THE SMELL OF FRESHLY PLOWED SOIL: A Natural History of the Underground WORMS Population growth over the next three decades will require a 50-percent increase in food production. If we hope to feed ourselves, we had better treat our earthworms better. Frank Lange leads me up a short lane from his shop to a recently harvested lentil field. "Know what those bumps are?" he asks. The field is covered with little mounds of dirt, each not quite an inch high. Even the compacted road, where the trucks hauled the harvested lentils out of the field, is covered. "Worms?" He nods. Although Lange considers them a gauge of his soil's health, worms are not something you expect in a lentil field. Not one worked by conventional tillage, anyway. Massive machinery, pulled in multiple sweeps across the Palouse loess soil, combined with any number of insecticides and other farm chemicals, does not make for a welcome habitat for earthworms. But here they are. Each of what must be millions of earthworms has lent its signature of approval across Lange's field. Lange avoids excess disruption of his field's ecosystem by seeding directly into untilled soil—a process called, appropriately, "no-till." Besides other benefits, his style of no-till results in very little erosion. He and an increasing number of farmers and scientists are agreeing extraordinary times require extraordinary—and gentler—methods. According to an article in the 1997 State of the World, we have just entered a whole new era in food production. For the first time, writes Gary Gardner, "the entire burden of increased grain production rests on yields alone." Population growth over the next three decades will require a 50-percent increase in food production. "The need for extra food will grow still further," he writes, "if rising incomes in developing countries continue to spur an increase in demand for livestock products, oilseeds, fruits, and vegetables." Projections by the Population Reference Bureau indicate a global population increase of 2.4 billion people over the next 25 years. In spite of the fleeting promise of the Green Revolution, increases in productivity are not keeping up with population growth. In nearly every year since 1985, writes Gardner, grain yields have grown more slowly than global population. On top of that, cropland is disappearing. Worldwide, between 1950 and 1981, grain area per capita shrank by 30 percent. Again, a rising standard of living in some areas of the world is chipping away at farmland, through urbanization and other aspects of an adopted Western culture. Lester Brown, in the same State of the World, notes that 40 golf courses were recently built in the fertile Pearl River Delta agricultural region of China's Guangdong Province. Although China brought new land into production between 1987 and 1992, its net losses still totaled some 3.87 million hectares. In Thailand, between 1989 and 1994, one golf course was built every 11 days. Gardner notes that at 160 to 320 hectares each, the golf courses displaced up to 34,000 hectares—"an area that, if planted in grain, would have supported hundreds of thousands of people." In the U.S., he continues, "some 168,000 hectares—the equivalent of two New York Cities—were paved over each year between 1982 and 1992." Closer to home, a study by Linda Klein, a former research associate in WSU's Department of Crop and Soil Sciences, found that between 1982 and 1992, farmland in western Washington declined by nearly 16 percent. Her report, published in the Journal of Soil and Water Conservation (January 1997) also argues that farmland protection programs in western Washington have been ineffective. (Also, see Universe, Spring 1995, p. 36.) Can we feed ourselves? A recent report in Science magazine concluded with a cautious "yes." But that conclusion was based on outdated population projections from the U.N., half that of current projections from the Population Reference Bureau. Despite much promise and hype, genetic engineering has yet to bear much fruit. Synthetic fertilizer has done as much as it can to boost the productivity of contemporary varieties. So demands on agriculture are shifting efforts back to what was there to start with, the natural soil ecosystem. If productivity on existing land is going to increase, even a surprising breakthrough in plant productivity will require that we preserve and nourish what soil we have to work with. That requires understanding—an understanding that is far from complete. But the presence of worms in Frank Lange's lentil field is a step in the right direction. | U N I V E R S E M A G A Z I N E H O M E | |
