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Lessons from the green revolution

POSTED 24 APRIL 2008


Agricultural research – necessary but not sufficient
One key lesson of the green revolution was that research and crop breeding must harmonize with the social, economic and physical setting where the crops will be used. Food problems do not exist in isolation: the world population is still growing, more people are eating meat and dairy products, environmental stresses are gaining intensity, and little or no good land remains to be plowed.

A poor environment for farming?
Let’s glance at some of the social, environmental and economic factors that influence food production.

kernelFarming the badlands
Farmland is a limited resource, and it is taking a beating. Cities, highways and suburbs are eating up acreage, yet even land that remains in production is suffering, as soil washes away in the rain or blows in the wind. Soil erosion costs Africa an estimated 8 percent of agricultural productivity; land degradation may cost 20 percent of productivity in several Asian and African countries.

Graph shows six groups of five bars, each bar varies from group to group and no two are the same
By 1990, over-grazing, vegetation removal and urbanization had degraded 38 percent of the world’s farmland, reducing its ability to produce food. We figure that number has risen since 1990. Graph: World Resources Institute

Nor are the prospects for expansion great: Cutting forests is often a temporary solution, as the exposed soil quickly loses fertility. The non-farmed land that might, theoretically, enter production usually has some combination of poor rainfall, poor soil and poor climate. And much of it is covered with irreplaceable forests.

kernelWater woes
Irrigation was a key to the green revolution, but the expansion of irrigated area has slowed from 2 percent to 1 percent per year, due to costs and competition for water. Furthermore, over the long term irrigation can destroy fertility by turning the soil salty. Meanwhile, global warming is melting glaciers, which supply many rivers in dry regions of the Middle East, Asia and Americas. In 2006, mountain glaciers lost more water than in any year since the series of measurements began in 1980.

Now that many rivers are being fully tapped to water farms and cities, how long will it be before melting glaciers dry up rivers, slashing farm output in dry lands?

Groundwater is unlikely to fill in if the rivers fail. After decades of declines in the giant Oglalla Aquifer in the U.S. plains states, the water table has also begun falling across northern China. China is building a massive national water carrier to bring water to the arid North.

It’s the economy, stupid
Although hundreds of millions of people raise crops mainly to feed themselves, we non-farmers who like to eat must encourage farmers to grow products for the market, and cash-crop farmers need a reason to assume the risk and expense of farming, says agronomist William Tracy.

A lone researcher leans over a plant in a large field cut into several different plots

Plant breeding, fertility, weed control and irrigation are important, he says, but they don’t explain the whole productivity picture. When Tracy looked at historical data on 16 U.S. crops, including some records that began in 1860, he found that “almost all showed no yield increase, and then they started going up in the 1930s. These crops “were biologically very different, some were southern, some northern, there were perennials and grains, and I thought, this is really weird. Then it dawned on me … this was a social phenomenon. In the 1930s, under the New Deal, the government basically said ‘We need to support farmers, make sure they get paid for what they grow. The government created price supports, and as soon as farmers realized they could start making money by growing food, crop productivity skyrocketed. The farmers have to get a fair return for what they do, and if they don’t, there is not much sense in buying more nitrogen or irrigation systems.”

Beware biofuel subsidies
A final factor affecting the food supply is the sudden fascination for producing biofuels like ethanol and biodiesel from corn, other grains and sugar cane. Biofuel production is soaring: Three farmers stand on flooded rice paddy bent over their crop, the peaks of  mountains visible in the distanceThis year ethanol could absorb up to 20 percent of the U.S. corn harvest (that’s the largest grain crop in the world, weighing in at roughly one-third of a billion metric tons in 2007).

Farmers irrigate rice paddies with water from the Bewail Dam, in Tanzania. Irrigation is one of the best ways to boost crop productivity – if the expertise, money and technology are available to bring in the water. And if the water is available in the first place. Photo: International Fund for Agricultural Development

That diversion has consequences, says C. Ford Runge, an economist at the University of Minnesota (see #8 in the bibliography). “Hunger is already happening. The global rate of increase in the price of grains, in one year, was 28 percent, causing the World Food Program to issue an emergency funding request ” (yes, you can donate!) to cover its budget shortfall. “The people who are really hurting are the subsistence farmers in Bangladesh, or people in the slums of Lagos or Mexico City,” Runge says.

Despite their questionable benefits for energy security and environmental health, the United States, Brazil and the European Union are pushing biofuels to reduce greenhouse gases and/or dependence on oil imports. U.S. fuel companies, for example, are paid 51 cents per gallon to blend ethanol into gasoline, and the domestic U.S. industry is sheltered by a 54 cent per gallon tariff on imported ethanol.

None of which makes economic sense, Runge says. “After 100 years of plant breeding and technological change, the U.S. has a huge comparative advantage in producing corn … but we decided to divert Woman crawls on ground to reach lowest green plant, wearing a brown head scarfWoman crawls on ground to reach lowest green plant, wearing a brown head scarf30 percent of the crop [which is one estimate of the ultimate amount diverted] into the manufacture of a fuel that costs twice as much as it costs Brazil to make from sugar cane… From an economic point of view, this is completely bass ackward.”

A woman harvests greens in Bangladesh. People in rich countries may complain about higher food prices, but it’s in places like Bangladesh or Rwanda where the food crisis is really biting. Photo: International Fund for Agricultural Development

Biofuels have, for the first time, placed hungry people in competition with empty gas tanks. But there are signs that the ethanol boom may be leveling off. Howard John O'Neil III, an economist with Kansas State University, says the price of corn has made industry chary of building new plants. “The economics for ethanol has changed over the last year and half. Just because you applied for a permit, does not mean you are going to stick a shovel in the ground” and build the plant.

And the lessons of the green revolution are…
The soaring demand for food clearly entails a second green revolution, but improved crops are not, by themselves, sufficient. We also need to think about better transportation to market, farmers education, setting smart economic and government policies, slowing down the number of new mouths to feed, or even learning to move around without burning so much fossil fuel. (Okay, maybe we’re dreaming …)

At long last, some lessons from the green revolution:

corn kernelCrop breeding works, but it takes decades to realize the full benefits.

corn kernelPlant breeding costs money… but there is no other way to start a surge in food production.

corn kernelSome farmers, and some regions, will benefit from technology long before others do.

corn kernelExternal factors matter. Weather, irrigation potential and farmer knowledge are all critical to higher productivity.

corn kernelArid regions with infertile soil and poor farmers are the cutting edge of the world’s quest to feed itself, where huge benefits await agriculturalists who can solve the moisture-fertility crisis..

The smart application of technology already defused a food crisis that loomed after World War II, and let’s hope we are about to witness a repeat. After all, a hungry planet ignores plant breeding, agriculture and fair, intelligent policies at its peril.

More lessons from the green revolution in the bibliography.

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Megan Anderson, project assistant; Terry Devitt, editor; S.V. Medaris, designer/illustrator; David Tenenbaum, feature writer; Amy Toburen, content development executive

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