sustainability is
A system or process is sustainable if it can be continued indefinitely, without depleting any of the material or energy resources required to keep it running.The term was first applied to the idea of sustainability yields in human endeavors such as forestry and fisheries. Trees, fish, and other biological species normally grow and reproduce at rates faster than that required just to keep their population stable. This built in capacity allows every species to increase or replace a population following some natural disaster.
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