Biological Criteria

The presence, condition and numbers of types of fish, insects, algae, plants, and other organisms provide important nformation about the health of aquatic ecosystems. Studying these factors as a way of evaluating the health of a body of water is called biological assessment. Biological criteria are a way of describing the qualities that must be present to support a desired condition in a waterbody and serve as the standard against which assessment results are compared.

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