Rethinking Bioassessment of Freshwater Ecosystem Health

This book provides the background, knowledge, and tools to model and assess the health of freshwater ecosystems. For more than 100 years, freshwater scientists have used the biota living in an ecosystem to assess the effects of human activity (bioassessment), and in the last 50 years, in jurisdictions around the world, bioassessment of freshwater ecosystems has been embedded in legislation. In the 1990s, there was general acceptance of the so-called “Reference Condition Approach" to bioassessment - the biota in a given type of healthy ecosystem (e.g., wadable stream, inland lake) vary in space and time so any judgement of ecosystem health or sickness has to take this variability into account.