Soil water picks up carbon dioxide generated when soil organic matter decomposes, and this then escapes to the atmosphere. This study should give pause to those who insist that man-made materials be biodegradable. When biodegradable materials decompose they add CO2 back into the atmosphere more quickly than otherwise. Nonbiodegradable materials serve to keep organic carbon buried and hence keep CO2 from rapidly escaping back into our atmosphere.

Kenneth M. Towe
Eatonton, Ga.

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