Concern for long-term availability of nonrenewable resources has fostered proposals for substitution with renewable resources. Forest products could become the basis for materials substitution and production. Further feasibility studies are needed to determine the technical, economic, energy, and environmental aspects of substitution. (MR)

The dynamics of growth have broadened concern over future materials supplies. The problem is multidimensional encompassing issues of depletion, materials cycles, recycling and substitution problems, energy, environmental costs, and economic growth. A new issue has also arisen demanding an international economic order between developed and…

Dwindling mineral resources might cause a shift from nonrenewable resources to renewable resources and inexhaustible elements such as iron and aluminum. Alternative energy sources such as breeder, fusion, solar, and geothermal power must be developed for production and recycling of materials. Substitution and, hence, living standards ultimately…