ハーマンデイリーHerman Daly -- 持続可能な開発の原則（Principles of Sustainable
出所： "Towards Some Operational Principles of Sustainable Development,"
Ecological Economics 2 (1990) 1-6. And, Meadows, D. et. al. Beyond the
Limits, Post Mills, Vermont: Chelsea Green Publishing Company, 1992.
For a renewable resource -- soil, water, forest, fish -- the
sustainable rate of use can be no greater than the rate of regeneration
(For example, fish are harvested sustainably when they are caught at a
rate that can be replaced by the remaining fish population);
For a nonrenewable resource -- fossil fuel, high-grade mineral
ore, fossil groundwater -- the sustainable rate of use can be no greater
than the rate at which a renewable resource, used sustainably, can be
substituted for it. (For example, an oil deposit would be used sustainably
if part of the profits from it were systematically invested in solar
collectors or in tree planting, so that when the oil is gone, an
equivalent stream of renewable energy is still available.);
For a pollutant the sustainable rate of emission can be no
greater than the rate at which the pollutant can be recycled, absorbed, or
rendered harmless by the environment. (For example, sewage can be put into
a stream or lake sustainably at the rate at which the natural ecosystem in
the water can absorb its nutrients).