July 8, 1990

Between 1950 and 1984, world grain production grew more quickly than the population, increasing nearly threefold and boosting output per person by 40 percent. This increase was due to the expansion for grain acreage, agricultural chemicals, high yield crop varieties and improved management techniques.

Increased world grain production occurred until 1984 but it has fallen about 14 percent since then. Grain production in Latin America has declined 12 percent per person since 1981, 24 percent in India since 1983 and 22 percent in Africa since 1967, according to the Global Ecology Handbook (Beacon Press 1990).

Today it is estimated that from 40 to 60 million people die from hunger each year. Almost a billion people -- one-fifth of the human population -- do not consume enough calories for an active working life.Of course, declining food production does not account for all who are hungry in the world today. War, lack of adequate food distribution, poverty and other factors are involved. But food production must be enhanced if the above hunger figures are to be decreased in the future.

In addition to the general decline in grain production since 1984, total grain production fell sharply in 1987 and 1988, nearly 10 percent below 1986. The primary cause of this was severe drought in the United States, Canada and China. This drop in grain production caused world grain stocks to fall from a 101 day supply in 1986 to an estimated 54 day supply in 1989, the lowest since the late 1940s.

In speaking to this decline of grain production per capita in the world, Lester R. Brown, president of Worldwatch Institute, says, "Unless national governments are prepared to wage the war against hunger on a far broader front, it may not be possible to arrest the decline in per capita food production that is undermining the future of so many poor countries."

Brown, writing in State of the World 1990 (W.W. Norton Co.), believes that world agriculture is being increasingly affected by environmental trends and resource constraints. He says that nearly all forms of environmental degradation are adversely affecting food production:

• Soil erosion is slowly undermining the productivity of an estimated one-third of the world's cropland.

• Deforestation is leading to increased rainfall runoff and crop destroying floods.

• Air pollution and acid rain are damaging crops in many countries.

• Increased untraviolet radiation associated with stratospheric ozone depletion is reducing yields of some crops.

• Waterlogging and salinity are lowering the productivity of one-fourth of the world's irrigated cropland.

• Global climate change in the form of hotter summers may also be affecting crop production.

The effect of topsoil losses on U.S. land productivity has been documented by 14 studies on corn and 12 on wheat. The results for both corn and wheat showed that a loss of one inch of topsoil resulted in a 6 percent decrease in grain production. According to the United Nations Food and Agriculture Organization, worldwide soil erosion could reduce agricultural productivity by one-fourth between 1975 and 2000.

Australian Prime Minister Robert Hawke has said, "None of Australia's environmental problems is more serious than the soil degradation."It is clear that deforestation affects food production. It affects the water cycle and produces flooding. As millions of people use wood for fuel, the forest is decreased. As it gets more difficult to collect wood for fuel, farmers use animal dung for fuel. The loss of dung for fertilizer depletes the soil further.

Cars and coal-fired power plants produce air pollutants that threaten food production. A seven-year study by the U.S. EPA and the USDA concluded that ozone, sulfur dioxide and nitrous oxides are the most damaging air pollutants. Ground level ozone is the most damaging to crops. In experiments, increasing ozone concentrations from .04 ppm to .09 ppm reduced yields of crops dramatically. For corn, the loss went from 1 percent at .04 ppm to 13 percent at .09 ppm, for soybeans, from 7 percent to 31 percent, and for wheat from 4 percent to 27 percent.

While ground-level ozone reduces harvests, depletion of the ozone layer in the upper stratosphere and the increase in ultraviolet radiation reaching the earth may be causing further crop damage. Data from experiments indicate that each one percent increase in UV radiation lowers soybean yields by 1 percent also. If the ozone layer continues to be depleted, crop productivity is certain to be inhibited.

Finally, the global greenhouse effect will surely have an impact upon food production. In 1988, the hottest year in the last century, the three world's top food-producing countries suffered a reduced harvest as a result of heat and drought.

Although we need to learn much more about the relationship between agriculture (food production) and the deterioration of the environment, it is clear that we will need to reverse the deterioration of the environment in order for food production to keep pace with world population growth in the future.