Ecosystems of national parks.

The preservation and maintenance of natural park ecosystems, with modern man's being restricted to generally nonconsumptive uses of the park, represents one end of a spectrum of land use that extends through exploitation of natural ecosystems to the development of simplified agricultural ecosystems. Criteria for management of a park ecosystem must, of necessity, differ from criteria for other uses of land, since park management involves preventing or compensating for the influence of man. The objectives for natural areas appear to be ecologically feasible if it is recognized that these areas have a finite capacity for absorbing man's consumptive and disruptive influences. The interpretation of ecosystems to park visitors provides an opportunity to contribute to an environmental ethic that extends beyond the park environment.