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More just world could support more people, ecologists say

STANFORD -- Liberal doctrine says that a more equitable world would be a better world.

That notion gains support from an analysis of the relationship between social and economic equity and the capacity of Earth's life- support systems to sustain the human population, according to ecologists Paul Ehrlich of Stanford University and Gretchen Daily of the University of California-Berkeley.

Ehrlich and Daily presented their conclusions Thursday, Aug. 11, during a symposium on Ecological Economics at the annual meeting of the Ecological Society of America in Knoxville, Tenn.

"Given present resource consumption patterns and technologies, the human population has already exceeded Earth's carrying capacity," they said, "and yet it is projected to at least double in size before halting growth.

"The prospect of further expansion of the population makes it essential that societies capitalize on our species' ingenuity and behavioral flexibility to create a sustainable human enterprise. Otherwise, civilization may well collapse," Ehrlich and Daily said.

The researchers argued that government policies promoting equity are especially worth considering.

"Not only are many people morally offended by the gross inequities that presently characterize most societies and the world as a whole, but many lines of evidence indicate that these inequities are environmentally as well as socially unsustainable," they said.

"Equity," they said, "is a measure of the similarity among individuals or groups in access to social, economic and political rights, material resources, health, education and other ingredients of human well-being."

Inequities generate cycles

The team pointed out that inequities generate vicious cycles involving deleterious and sometimes irreversible impacts on biophysical components of Earth's life-support systems.

"The situation has the characteristics of a 'social trap,' " they said. "Population growth encourages inequity, while inequity apparently lowers carrying capacity and may increase population growth."

As an example, Ehrlich and Daily cited unequal access to jobs for men and women as "an important factor leading to birth rates that are too high. Female education and economic opportunities are important in their own right; in addition, they are keys to lowering fertility rates in poor countries and in poor segments of rich countries.

"Before job opportunities for women become available, parents viewed children primarily as an investment. For mothers they often provide a claim on the income of the fathers, and for both parents they represent an important source of future financial support to avoid an old age of severe poverty.

"After jobs open up, the view of children is transformed into one of consumption items - 'consumer durables.' Having a child then means supporting it and forgoing other consumption, such as the purchase of a refrigerator or a television. As a result, families choose to have many fewer children."

Earth's 'carrying capacity' may decrease

Ehrlich and Daily also said that the trend of industrial agriculture forcing family farms out of business was likely to lower Earth's carrying capacity (the number of people the planet can sustain over the long term). "Family farmers who own their land generally wish to pass it on to the next generation in as good or better condition than they received it. This encourages a level of careful soil conservation difficult to attain in the high-discount world of industrial farming.

"Land reform in poor countries," they continued, "could increase the current productivity of agriculture and also lead to better husbandry of agricultural resources in the long term." Inequitable land distribution displaces landless farmers to mountainsides and other areas unsuitable to growing crops, causing deforestation and soil erosion and perpetuating poverty and rapid population growth, they said.

"Inequities also hinder cooperation among parties of differing socioeconomic status - cooperation that is necessary to avoid or mitigate the potentially disastrous consequences of population- and environment- related problems. For example, slowing global warming, controlling mass migrations across international borders, and preserving biodiversity all will require an unprecedented level of international cooperation."

They also said that the one way in which "increasing equity could guarantee the destruction of civilization would be to try to achieve equity in material consumption globally by leveling up consumption from the bottom." Instead, overdeveloped, rich nations will need to find ways to curb their wasteful consumption while increasing their quality of life, which is entirely possible using technologies in hand today.

"We cannot depend on everything being done right," they said. "Humanity must have a substantial margin for error between the size of the population and Earth's carrying capacity."

Ehrlich and Daily said that, considering the difficulties of achieving greater equity and the "fog of politics" (the high probability of bad policies badly administered), greater effort should be put into the difficult task of reducing the scale of the human enterprise.

"That means stopping population growth as soon as humanely possible, then starting a gradual population decline; reducing consumption per person in rich nations; and working everywhere to improve the efficiency of the technology that serves the consumption. Only success in that endeavor is likely to lead to a sustainable civilization."

For those interested in promoting both equity and sustainability, Ehrlich and Daily said, it seems ideal that the policy strategies designed to bring about each coincide.



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