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Feeding a Growing World Population


Saving Nature's Legacy Through Better Farming

Unless growing world food demand is met with improved farm productivity, much undeveloped and with its biodiversity will be lost to agriculture.

The obvious environmental problems and solutions are not necessarily obvious at all. Organic farming and the time-proven techniques of traditional agriculture hold great emotional attraction. Pure foods without chemical fertilizers and pesticides seem clearly preferable to the methods of large agribusiness. Could they be the cure for the unrelenting destruction of earth's forests and its diverse flora and fauna?

Ironically, developed world demands for these "obvious" solutions may push the world into famine and destroy the planet's biodiversity far faster than chemicals and overpopulation. Only the judicious application of the "evils" of high-yield farming may give us the time to prevent such calamities. Contrary to common wisdom, saving the environment and reducing population growth are likely to come about only if governments significantly increase their support for high-yielding crops and advanced farming methods, including the use of fertilizers and pesticides.

The biggest danger facing the world's wildlife is neither pesticides nor population growth but the potential loss of its habitat. Conversion of natural areas into farmland is the major impact of humans on the natural environment and poses a great threat to biodiversity. About 90 percent of the known species extinctions have occurred because of habitat loss.

Whereas many industrialized countries see their farms occupying less and less of their land, worldwide the opposite it true. The World Bank reports that cities take only 1.5 percent of earth's land, but farms occupy 36 percent. As world population climbs toward 8.5 billion in 2040, it will become even more clear how much food needs govern the world's land use. Unless we bolster our efforts to produce high-yielding crops, we face a plow-down of much of the world's remaining forests for low-yield crops and livestock.

Greens versus green revolution

For decades and certainly since the 1968 publication of Paul Ehrlich's The Population Bomb, overpopulation has riven the world's conscience. Each regional famine catalyzed by crop failures or weather bring it further to the fore. Yet we seem unaware of how crucial the green revolution has been in forestalling famine and simultaneously saving the environment.

By maximizing land use, the green revolution's high-yield crops and farming techniques have been vital in preserving wildlife. By effectively tripling world crop yields since 1960, they have saved an additional 10 to 12 million square miles of wild lands, according to an analysis that I conducted and which was published in early 1997 in Choices, the magazine of the American Agricultural Economics Association. Without the green revolution, the world would have lost wild land equal to the combined land area of the United States, Europe, and Brazil. Instead, with hybrid seeds and chemical fertilizers and pesticides, today we crop the same 6 million square miles of land that we did in 1960 and feed 80 percent more people a diet that requires more than twice as many grain-equivalent calories.

The green revolution, however, has had its detractors. Since the publication of Rachel Carson's Silent Spring in 1962, developed-world residents have been bombarded with claims that modern farming kills wildlife, endangers children's health, and poisons the topsoil. Understandably, we love the natural ways of life. For many centuries, humans seemed to grow their crops quite well without deadly chemicals that poison soil, plants, insects, and animals. The organic gardening and farming movements look fondly on that ideal. Unfortunately, those techniques are ill suited to the modern world for two strong reasons.

First, they worked in a much less populous world. Such techniques and the plants they favor require large amounts of relatively fertile land supporting small numbers of people. In modern Europe, Asia, and the developing world, such low-yield farming is impractical. Second, many of those techniques are incredibly destructive to soil and forests, degrading biodiversity quickly and irrevocably. Slash-and-burn agriculture, the time-honored primitive farming method, is perhaps the most harmful to the environment.

Ironically, in a world facing the biggest surge in food demand it will ever see, many environmentalists who want to preserve natural areas are recommending organic and traditional farming systems that have sharply lower yields than mainstream farms. A recent organic farming "success" at the Rodale Institute achieved grain-equivalent yields from organic farming that were 21 percent lower and required 42 percent more labor. Such yields may be theoretically kinder to the environment, but in practice they would lead us to destroy millions of square miles of additional natural areas.

Meanwhile, Greenpeace and the World Wildlife Fund have gathered millions of European signatures on petitions to ban biotechnology in food production. They do not protest the use of biotechnology in human medicine, but only where it will help preserve nature by increasing farm productivity.

No meat, no thanks

Humans might be able to meet their nutritional needs with less strain on farming resources by eating nuts and tofu instead of meat and milk. So far, however, no society has been willing to do so. For example, a Vegetarian Times poll reported that 7 percent of Americans call themselves vegetarians. Two-thirds of these, however, eat meat regularly; 40 percent eat red meat regularly; and virtually all of them eat dairy products and eggs. Fewer than 500,000 Americans are vegan, foregoing all resource-costly livestock and poultry calories. The vegetarian/vegan percentages are similar in other affluent countries.

The reality is that as the world becomes more affluent, the average person will be eating more meat and consuming more agricultural products. If population growth stopped this hour, we would have to double the world's farm output to provide the meat, fruit, and cotton today's 5.9 billion people will demand in 2030 when virtually all will be affluent. There are no plans, nor any funding, for a huge global vegan recruiting campaign. Nor does history offer much hope of one's success.

Meanwhile, in what used to be the poor countries, the demand for meat, milk, and eggs is already soaring. Chinese meat consumption has risen 10 percent annually in the past six years. India has doubled its milk consumption since 1980, and two-thirds of its Hindus indicate that they will eat meat (though not beef) when they can afford it.

According to the United Nation's Food and Agricultural Organization (FAO), Asian countries provide about 17 grams of animal protein per capita per day for 3.3 billion people. Europeans and North Americans eat 65 to 78 grams. The Japanese not long ago ate less than 28 grams, but are now nearing 68 grams. By 2030, the world will need to be able to provide 55 grams of animal protein per person for four billion Asians, or they will destroy their own tropical forests to produce it themselves. It will not be possible to stave off disaster for biologically rich areas unless we continue to raise farm yields.

To make room for low-yield farming, we burn and plow tropical forests and drive wild species from their ecological niches. Indonesia is clearing millions of acres of tropical forest for low-quality cattle pastures and to grow low-yielding corn and soybeans on highly erodable soils to feed chickens. Similarly, a World Bank study reports that forests throughout the tropics are losing up to one-half of their species because bush-fallow periods (when farm lands are allowed to return to natural states) are shortened to feed higher populations.

Pessimists have said since the late 1960s that we won't be able to continue increasing yields. However, world grain yields have risen by nearly 50 percent in the meantime. If we'd taken the pessimists' advice to scrap agricultural research when they first offered it, the world would already have lost millions of square miles of wildlife habitat that we still have.

Nor is there any objective indication that the world is running out of ways of increasing crop yields and improving farming techniques. For example, world corn yields are continuing to rise as they have since 1960, at about 2.8 percent annually, in what's rapidly becoming the world's key crop. The yield trend has become more erratic, mainly because droughts decrease yield more in an eight-ton field than they do in a one-ton field. U.S. corn breeders are now shooting for populations of 50,000 plants per acre, three times the current corn belt planting density, and for 300-bushel yields.

The biggest danger facing the world's wildlife is neither pesticides nor population growth but the potential loss of habitat.

Also, the International Rice Research Institute in the Philippines is redesigning the rice plant to get 30 percent more yield. Researchers are putting another 10 percent of the plant's energy into the seed head (supported by fewer but larger stalk shoots). They're using biotechnology techniques to increase resistance to pests and diseases. The new rice has been genetically engineered to resist the tungro virus--humanity's first success against a major virus. The U.S. Food and Drug Administration is close to approving pork growth hormone, which will produce hogs with half as much body fat and 28 percent more lean meat, using 25 percent less feed grain per hog. Globally, that would be equal to another 20 to 30 millions tons of corn production per year.

The world has achieved strong productivity gains from virtually all of its investments in agricultural research. The problem is mainly that we haven't been investing much. One reason for underinvesting is pessimism about much can be gained through research. But if humanity succeeds only in doubling instead of tripling farm output per acre, the effort will still save millions of square miles of land. Besides, the more pessimistic we feel about agricultural research, the more eager we should be to raise research investments because there is no doubt that we will need more food.

Saving the soil

Throughout history, soil erosion has been by far the biggest problem with farming sustainability. Modern high-yield farming is changing that situation dramatically. Simple arithmetic tells us that tripling the yields on the best cropland automatically cuts soil erosion per ton of food produced by about two-thirds. It also avoids pushing crops onto steep or fragile acres.

Relatively new methods such as conservation tillage and no-till farming are also making a big difference. Conservation tillage discs crop residues into the top few inches of soil, creating millions of tiny dams against wind and water erosion. In addition to saving topsoil, conservation tillage produces far more earthworms and subsoil bacteria than any plow-based system. No-till farming involves no plowing at all. The soil is never exposed to the elements. The seeds are planted through a cover crop that has been killed by herbicides. The Soil and Water Conservation Society says that use of these systems can cut soil erosion per acre by 65 to 95 percent.

Organic farmers reject both these systems because they depend on chemical weed killers, not plowing and hoeing, to control weeds. However, these powerful conservation farming systems are already being used on hundreds of millions of acres in the United States, Canada, Australia, Brazil, and Argentina. They have been used successfully in Asia and even tested successfully in Africa.

The model farm of the future will use still-more-powerful seeds, conservation tillage, and integrated pest management along with still-better veterinary medications. It will use global positioning satellites, computers and intensive soil sampling ("precision farming"), to apply exactly the seeds and chemicals for optimum yields, with no leaching of chemicals into streams. Even then, high-yield farming will not offer zero risk to either the environment or to humans. But it will offer near-zero and declining risk, which will be more than offset by huge increases in food security and wild lands saved.

Food security and lower birthrates

Food availability along with modern medicine have lowered the world's death rates, producing a one-time population growth surge. But they are also helping in the longer term to restabilize population by giving parents confidence that their first two or three children will live to adulthood.

Increased food security, for which crop yields are the best proxy, has been a vital element in sharply reducing world fertility rates. Indeed, according to World Bank and FAO statistics, the countries that have raised their crop yields the fastest have generally brought their births per woman down the fastest. For example, Indonesia has increased its rice yields since 1960 by 250 percent and its births per woman have dropped from 5.5 to 2.9. Likewise, Zimbabwe more than doubled its corn yields with Africa's best plant-breeding program, while births per woman have dropped from 8 in 1965 to 3.5 today. In contrast, countries without high-yield trends have kept higher fertility rates. In Ethiopia, which has suffered famine instead of rising yields, births per woman have risen from 5.8 in 1965 to more than 7 today.

Environmentalists seem unaware of how cruical the green revolution has been in preventing famine and preserving biodiversity.

Unfortunately, the world is not gearing up its science and technology resources to meet the agricultural and conservation challenge. U.S. funding for agricultural research has declined for decades in real terms, though the cost and complexity of the research projects continue to rise with the size of the challenge. The federal and state governments increased their spending on agricultural research from $1.02 billion in 1978 to $1.65 billion in 1990, a one-third decline in constant dollars. Public funding rose to $1.8 billion in 1996. Likewise, private sector agricultural research spending rose from $1.5 billion in 1978 to $3.15 billion in 1990, a 15 percent real decline.

Overseas, the research funding picture is worse. Europe has never spent heavily on agricultural research. Only a few of the developing world countries, including Brazil, China, and Zimbabwe, have even sporadically spent the few millions of dollars needed to adapt research to their own situations. All told, the entire world's agricultural research investment is probably less than $15 billion a year.

A telling example of the world's cavalier attitude toward agricultural research occurred in 1994, when the United States and other donor nations failed to come up with a large part of the budget for the Consultative Group on International Agricultural Research (CGIAR). CGIAR is the key international vehicle for creating high-yielding crops, supporting a network of 16 agricultural research centers in developing countries. Thus, global agricultural research almost literally went bankrupt at the very moment the world was pledging another $17 billion for condoms and contraceptive pills at the UN meeting on population in Cairo. The World Bank subsequently stepped in on a conditional basis to keep the CGIAR research network running.

Historically, the U.S. Agency for International Development (AID) provided about 25 percent of CGIAR research funding, or about $60 million a year. Currently, this has fallen to about $30 million per year in much cheaper dollars, or about 10 percent of AID's budget. Indeed, despite the centers' success in raising world crop yields, AID has since shifted its priorities sharply from agricultural research to family planning. Given the sharp downward trends in birthrates in developing countries, additional family planning funds are likely to make only a modest difference in the world's population. However, Western intellectuals and journalists highly approve of population management.

In sum, world spending on agricultural research is tiny, especially if you consider that in 1996, the U.S. food industry alone produced $782 billion in goods and services and that the federal government subsidizes farmers to the tune of nearly $100 billion a year. (The European Union spends another $150 billion a year on farm sbsidies.) Meanwhile, agricultural research has saved perhaps one billion lives from famine, increased food calories by one-third for four billion people in the developing world, and prevented millions of square miles of often biologically rich land from being plowed down.

We shouldn't be too surprised at the lack of approval and funding for high-yield agricultural research. Industrialized countries, which have funded most modern farming research, have been surrounded for the past 40 years with highly visible surpluses of grain, meat, and milk. Too many citizens associate the surpluses with science, not with ill-conceived farm price supports and trade barriers.

Western Europe watched its farm population decline from about 28 percent in 1960 to about 5 percent today. This followed an earlier but similar decline in the number of U.S. farmers. Both Europe and the United States associate the decline of the small family farm with the rise in crop yields, not with the rising value of off-farm jobs.

Securing the future

Feeding the world's people while preserving biologically rich land will require two key things: more agricultural research and freer world trade in farm products. Expanded agricultural research should be the top priority.

Congress should double the federal government's $1.4 billion annual investment in agricultural research and adopt substantially higher farm yields as one of the nation's top research priorities. No other nation has the capacity to step into the U.S. research role in time to save the wild lands. Congress should also release much of the cropland still in the U.S. Department of Agriculture's (USDA) Conservation Reserve Program for farming with conservation tillage, and it should direct AID to make the support of high-yield agriculture at least as important as population management.

In addition, in order to use the world's best farmland for maximum output, farm trade must be liberalized. Farm subsidies and farm trade barriers, although they are beginning to be reduced, have not only drained hundreds of billions of dollars in scarce capital away from economic growth and job creation, they now represent one of the biggest dangers to preservation of biologically diverse lands. The key dynamic in the farm-trade arena is Asia's present and growing population density. Without an easy flow of farm products and services, densely populated Asian countries will be tempted to try to rely too much on domestic food production. But it will be extremely difficult to do. By 2030, Asia will have about eight times as many people per acre of cropland as will the Western Hemisphere. It already has the world's most intensive land use. In reality, countries reduce their food security with self-sufficiency. Droughts and plagues that cut crop yields are regional, not global.

The United States must convince the world that free trade in farm products would benefit all, particularly those in developing countries. President Clinton should make free farm trade a top international priority, which could give momentum to the World Trade Organization's scheduled 1999 talks on liberalizing trade in agricultural products.

Changes in attitude

Finally, a renewed emphasis on high-yield farming aimed at preserving biodiversity will require a change in mind-set on the part of key actors: environmentalists, farmers, and government regulators in particular. The environmental movement must postpone its long-cherished goal of an agriculture free from man-made chemicals and give up its lingering hope that constraining food production can somehow limit population growth. Until we understand biological processes well enough to get ultrahigh yields from organic farming, environmentalists must join with farmers in seeking a research agenda keyed primarily to rapid gains in farm yields whether they are organic or not.

Farmers must accept that environmental goals are valid and urgent in a world that produces enough food to prevent famine. They must collaborate constructively and helpfully in efforts such as protecting endangered species and improving water quality. Without such reasonable efforts, farmers will not get the public support for high-yield farming systems and liberalized farm trade.

Government regulators at all levels must realize that chemical fertilizers, pesticides, and biotechnology techniques are powerful conservation tools. For example, the Environmental Protection Agency (EPA) must stop regarding a pesticide banned as a victory for the environment. Having dropped the economic rationale protecting some high-yield pesticide uses, EPA should now take into consideration the potential for new pest-control technologies to save wild lands and wild species through higher yields, both nationally and globally.

Education can play a big role in changing the mind-sets of the various actors. For example, the U.S. Department of State, which has already announced an environmental focus for U.S. foreign policy, could work to ensure that the concept of high-yield conservation is appropriately encouraged in international forums. The U.S. Department of Education could collaborate with USDA to help the nation's students understand the environmental benefits of high farm yields.

On all fronts, this is a time for pragmatism. We know that high-yield farming feeds people, saves land, and fosters biodiversity. We know that agricultural research is the surest path to those same goals. The narrower goals should be subsumed into the larger ones for the short- to mid-term future. A combination of agricultural science and policy can combine for the welfare of the planet, its people, its animals, and its plants. Achieving those crucial aims will mean rethinking population, farming methods, fertilizers, and many related controversial aspects of agriculture.

Recommended reading

Dennis Avery, "Environmentally Sustaining Agriculture," Choices, first quarter, 1997.

Dennis Avery and Alex Avery, Farming to Sustain the Environment. Hudson Institute Briefing Paper #198, May 1996.

Alex McCalla, Agriculture and Food Needs to 2825: Why We Should Be Concerned. Washington, D.C.: Department of Agricultural and Natural resources, The World Bank, 1994.

Mark Rosegrant and Claudia Ringler, Why Environmentalists are Wrong about the Global Food Situation: Methods and Myths. Paper presented at the International Conference of Agricultural Economists, Sacramento, Calif., August 18, 1997.

David Seckler and Gerald Cox, Population Projections by the United Nations and the World Bank: Zero Growth in 48 Years. Arlington, Virg.: Winrock Institute for International Development, 1994.

Farming for a Better Environment. Ankeny, Iowa: Soil and Water Conservation Society, 1995.

Robert Thompson, Technology, Policy and Trade: The Keys to Food Security and Environmental Protection. Presidential address, International Conference of Agricultural Rconomists, August 18, 1997.

Paul Waggoner, How Much Land Could 18 Billion People Leave for Nature? Ames, Iowa: Council for Agricultural Science and Technology, 1994.

Dennis T. Avery directs the Hudson Institute's Center for Global Food Issues.