Refers to agricultural and other practices that depend upon nonrenewable (or non-replaceable) resources-such as fossil fuel, topsoil, or groundwater that eventually will be depleted.

The present use, consumption or harvesting of natural resources that can not be continued into the future.

To present participles which come from intransitive verbs, or are themselves employed as adjectives, to mark the absence of the activity, disposition, or condition implied by the participle;