"Parks Canada defines ecological integrity as 'a condition where the structure and function of an ecosystem are unimpaired by stresses induced by human activity and are likely to persist' (Parks Canada Guiding Principles and Operational Policies, 1994). In other words: a national park has ecological integrity if all the plants and animals that should be in the park still thrive there, and people use the park and its surroundings in ways that respect the needs of those plants and animals and allow fires, floods, weather and other natural processes to create natural habitat. Ecological integrity is measured in terms of:
ecosystem health, including the ability to evolve, develop, and adapt to change;
biological diversity, including the ecological and evolutionary processes that keep species functioning;
the ability of plant and animal communities to resist or adapt to stresses and change;
the ability of plants and animals to sustain healthy populations; and
the integration of people into the environment in ways that sustain both human quality of life and biological diversity."
(Jasper National Park of Canada Management Plan, Section 3.1; 2010)
See also this Parks Canada web page.