AT FIRST the connection might not be obvious, but the best way to protect the world's environment is to educate girls and women in the Third World. Nowhere is this more important than in the poorest of the poor countries where people exist on $1 a day.
Without extensive financial aid, these countries cannot spend enough on education. One important source of aid is the International Development Association, a lending affiliate of the World Bank that 34 donor countries, including the United States, recently agreed to refund for the 10th time. Now, the parliaments of these nations will have to approve the agreement.
Why does female education have such a powerful effect?
First, women manage many of the planet's natural resources -- especially in Africa. More than two-thirds of the farms in the Congo are run by women. All too often, though, women are denied such basic tools as legally protected land rights or access to credit. Education raises women's economic and social status and makes it harder for this kind of damaging discrimination to continue.
Second, educated women have fewer babies, which is good news for the environment. In many parts of the world, girls are expected only to marry and bear children. Parents limit their daughters' education accordingly. If household resources are limited, why invest in a child's education if there is no prospect of economic return?
Making education available to girls breaks up this vicious cycle. Educated women are presented with economic alternatives to early marriage and childbearing, and they take them. Evidence from 72 developing countries shows that where no girls are enrolled in secondary education, a woman has an average of seven children, but where 40 percent of women have had a secondary education, the average drops to three, even after controlling for factors such as income.
How environmentally significant is this? A recent international Gallup survey shows that when asked to rate the severity of a half-dozen potential causes of environmental damage within their own country, 74 percent of Indian respondents cite overpopulation as contributing a "great deal." No other single cause is listed as frequently by Indians. For the Philippines and Mexico, the figures are 65 and 64 percent respectively. These numbers should come as no surprise; no one is better placed to assess the environmental costs of rapid population growth than those who pay them.
More people means more pressure on natural resources. Either existing land must produce more or new areas must be brought under cultivation. The first option has a remarkable track record. Over the past quarter-century, a "green revolution" of high-yielding seeds, chemical fertilizers, pesticides and irrigation has increased the production of cereal crops by 90 percent, far outstripping the 60 percent increase in population.
But things may not always be so successful. For instance, one way to increase crop yields in the short term is to reduce fallow times -- the period during which land is left uncultivated in order to restore soil fertility. But as fallow times shorten, nutrients are sucked from the soil and crop yields decline. People sink further into poverty. Low incomes, inadequate education and high infant mortality -- all closely linked to poverty -- then add to already high rates of population growth.
Population growth also drives people to cultivate environmentally fragile areas: steeply sloped, erosion-prone hillsides; semi-arid land where soil degradation is rapid; and tropical forests where crop yields on cleared fields drop after just a few years. Well over half of all tropical deforestation results from agricultural encroachment.
Today, most people live in rural areas, but in 40 years city dwellers will outnumber rural populations two to one. Cities are growing so fast that the number of people without access to adequate sewerage rose by more than 70 million during the 1980s. Already, the diseases stemming from contaminated water kill more than 3 million people each year, most of them children under 5.
It is figures like these that reveal the true importance of educating women. Over the next 40 years, world population is set to grow by 3.7 billion, 90 percent of it in developing countries. No previous generation has seen so large an increase; no successive one will. The World Bank now invests around $2 billion each year in education. But much more needs to be done.
There are other arguments for more female education. Educated women have far greater opportunities to earn a steady income -- and they are much more likely than their husbands to use some of that income on their children's education and to seek medical care for themselves and their families.
Investing in female education offers the greatest payoffs of any environmental policy. Dollar for dollar, no other policy does as much to make human development sustainable. Without adequate funding, tragedy threatens the environment and the world's poor.
Andrew Steer is deputy director of the World Bank's Environment Department. Will Wade-Gery is a consultant to the department.