World Demographic Shifts Signal Resource Crunch

HISTORY accelerates. Too often Americans focus on short-term change: change in taxes, change in budgets, change in first ladies' hair styles. Meanwhile, deeper forces of change sweep past with less notice, faster and faster.

Consider these examples of global trends, all taken from recent international organization reports:

Land. The world is now losing an area of agricultural land almost the size of Ireland to soil degradation every year, according to the Food and Agriculture Organization (FAO) of the United Nations.

People. The urban population of developing nations is growing so quickly that by 2025 it will be 16 times larger than it was in 1950, the UN Population Fund says.

Health. Since 1953 life expectancy has increased more than it did during all previous history, according to the World Bank.

The overall picture of these reports is one of growing pressure on resources, especially in the third world. And a large, restless third-world population is becoming the whole world's problem. Migration "could become the human crisis of our age," states the UN Population Fund study.

The size of developing-nation populations is already straining the soil. Over the past 45 years about 11 percent of the world's arable land has suffered moderate or severe degradation, according to the FAO.

In both Africa and Asia, 4 percent of the land surface has seriously deteriorated. By contrast, in North America, despite the dust bowl of the '30s, the figure is only 1.3 percent.

Overgrazing, deforestation, and destructive agricultural practices such as poor plowing are the main causes of land deterioration. One reason famines have struck Africa in recent years is that even good land is being depleted, lowering yields.

The African continent still has much land that could be converted to agriculture. But "few African countries can hope to achieve sustainable agriculture in the near future" because of land degradation, according to the FAO. Latin America and Asia are only marginally better off.

Meanwhile, people are leaving rural areas in droves. Every year, 20 million to 30 million of the world's poor leave their villages to move to the exploding cities of developing nations.

Megacities such as Mexico City and Calcutta are new phenomena, according to the UN population fund. Their 16-fold predicted rate of expansion is unprecedented. In the period of fastest growth for developed nations, from 1840 to 1914, their urban population grew only five times.

Megacities are growing so fast they cannot provide housing and services to new residents. "The economies of many developing countries are ill-equipped to support urban growth on its present scale," notes the UN Population Fund.

Increasingly, migrants are spilling across national borders. Currently, there are about 100 million international migrants of all kinds, according to the UN report. That represents about 2 percent of world population.

Of these, just short of 40 million are refugees fleeing violence or drought. The rest are in search of a better economic life. Whether they will find it is problematic, as they are often the most exploited and vulnerable of workers. In addition, they also risk a backlash of resentment, such as riots against foreigners in Germany and growing resentment of illegal aliens in the United States.

Not all global trends are negative. Forty-three years ago, life expectancy in the developing world was 40 years. Today life expectancy is 63 years. During the same period third-world child mortality rates have been more than halved.

Much of this health gain is attributable to simple practices such as increased use of vaccinations, according to the World Bank's World Development Report for 1993.

A large health gap between the developed and developing world still remains. If child mortality were at first-world levels all around the globe, 11 million children a year would be saved.

And the developing world is still dogged by misallocation of health funds, according to the World Bank. It urges spending less on high-tech urban hospitals and more on simple interventions such as AIDS prevention education and the provision of drugs for the prevention of such prevalent third-world diseases as snail fever.

"Government spending on health should be redirected to more cost-effective programs that do more to help the poor," the World Bank says.