Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: TUESDAY, February 22, 1994 TAG: 9402220109
SECTION: NATIONAL/INTERNATIONAL PAGE: A-1 EDITION: METRO
SOURCE: Associated Press
DATELINE: SAN FRANCISCO LENGTH: Medium
The alternative, if current trends continue, is a population of 12 billion to 15 billion people and a worldwide scene of "absolute misery, poverty, disease and starvation," said the study's author, David Pimentel, an ecologist at Cornell University.
In the United States, the population would climb to 500 million and the standard of living would decline to slightly better than in present-day China, Pimentel said at the annual meeting of the American Association for the Advancement of Science.
Even now, the world population of 6 billion is at least three times what the Earth's natural resources and energy reserves would be able to support comfortably in 2100, Pimentel said.
Pimentel defines "comfortably support" as providing something close to the current American standard of living, but with wiser use of energy and natural resources.
"If people do not intelligently control their own numbers, nature will. That we can count on," he said.
A decline to 1 billion or 2 billion people over the next century could be done by limiting families around the world to an average of 1.5 children, Pimentel said.
U.S. women now have an average of 2.1 children, as do the Swedes. The average in Rwanda is 8.5; Saudi Arabia, 6.4; Bolivia and Mongolia, 4.6; Argentina, 2.8; Germany, 1.5; Hong Kong, 1.4; and Italy 1.3, according to the United Nation's State of the World Population report.
Depletion of coal, oil and natural gas, along with uranium reserves, are one important limit on the number of people that can survive comfortably on Earth, he said.
The other two key limiting factors are cropland and water for irrigation, he said. Each factor leads to a calculation of a comfortably sustainable population of 1 billion to 2 billion in 2100, Pimentel found.
Sandra Postel of the Worldwatch Institute noted that until 1978, the amount of irrigated farmland around the world was growing faster than population. But in 1978 population growth began to outstrip the growth of irrigated land.
"That raises a red flag for food security in the future," she said. "The water constraints are going to be a major factor."
Many others have taken the view that population soon will outstrip resources. But advances in technology, such as the development of new higher-yielding crop varieties in the 1960s, forestalled catastrophe.
Pimentel argues, however, that there are no more technological solutions to be found.
by CNB