the condition of the aquatic community inhabiting unimpaired waterbodies of a specified habitat as measured by an evaluation of multiple attributes of the aquatic biota. Three critical components of biological integrity are that the biota is (1) the product of the evolutionary process for that locality, or site, (2) inclusive of a broad range of biological and ecological characteristics such as taxonomic richness and composition, trophic structure, and (3) is found in the study biogeographic region.
The ability of an ecosystem to support and maintain a balanced, integrated, and adaptive community of organisms having a species composition, diversity, and functional organization comparable to the best natural habitats within a region.
Ecological systems, such as forests, deserts and oceans, are sometimes weak and other times strong—just like you. When you are feeling healthy, strong and well-fed your physical body has high biological integrity. Landscapes are no different, only scientists call it biological integrity rather than health.