A. Renewable resources:
Renewable resources should be exploited in a manner such that:
(1) harvesting rates do not exceed regeneration rates; and
(2) waste emissions do not exceed the renewable assimilative capacity of the local environment.
B. Nonrenewable resources
Nonrenewable resources should be depleted at a rate equal to the rate of creation of renewable substitutes.
*These appear in several sources, but the original is found on page 227, Valuing the Earth: Economics, Ecology, Ethics, Herman E. Daly and Kenneth N. Townsend (1993, first edition 1977)
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