Ecoscience

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by Anne and Paul Ehrlich

Paul Ehrlich (Bing Professor of Population Studies and Professor of Biological Sciences, Stanford University) and Anne Ehrlich (Senior Research Associate, Department of Biological Sciences, Stanford) are familiar names to ecologists and environmentalists everywhere. As well they should be. Because it was Paul and Anne who—through their writing and research—gave special meaning to the words "population", "resources", and "environment" in the late 1960's. (They also coined the term coevolution, and did a lot to make ecology the household word it is today.) But while most folks are aware of the Ehrlichs' popular writing in the areas of ecology and overpopulation (most of us—for instance—have read Paul's book The Population Bomb) . . . far too few people have any idea of how deeply the Ehrlichs are involved in ecological research (research of the type that tends to be published only in technical journals and college textbooks). That's why it pleases us to be able to present—on a regular basis—the following semi-technical column by authors/ecologists/educators Anne and Paul Ehrlich.

The Threat of Nuclear Proliferation

Many people claim that they oppose nuclear power plants because they threaten "the ecology". Trained ecologists, however, often tend to take a different view. The scientists, you see, know that natural ecosystems are quite resilient in the face of increased levels of radioactivity. In fact, such living communities are actually more resistant to radiation than they are to the acid rains that result from the combustion of fossil fuels!

Therefore, from the point of view of the health of the ecosystem—rather than the health of people—nuclear power could be one of our more desirable energy options. It could, that is, except that the weapons connection must also be considered. Unfortunately, the spread of nuclear power plants is intimately connected with the spread of atomic bombs . . . called "nuclear proliferation" in current jargon. And atomic warfare, of course, is good for neither people nor ecosystems.

HOW IT WORKS

It is a sad fact that the knowledge required to build an atomic bomb is very widespread. Credible explosive devices have been designed by college physics students, and—in at least one case—by a high school boy! The basic idea is first to assemble a large enough mass of fissile material (uranium 233 or 235, or plutonium 239) and then hold it together long enough for a nuclear explosion to occur.

U-233, U-235, and P-239 nuclei undergo spontaneous splitting—fissioning—accompanied by the release of both energy and neutrons. If a neutron from a fissioning nucleus is "captured" by another fissile nucleus, it will fission, too . . . and release more energy and neutrons. When there are just enough other nuclei around to serve as targets so that a self-sustaining chain reaction occurs, there's said to be a critical mass. With proper controls (see "Is It Safe to Live Near a Nuclear Power Plant?" in MOTHER NO. 51, page 154), the heat from such a chain reaction can be used to make steam in a nuclear power plant. [EDITOR'S NOTE: Back issues are available for 83.00 each plus $1.00 shipping and han dling per order from THE MOTHER EARTH NEWS ® P.O. Box 70, Hendersonville, North Carolina 28791.