Using Biological Response Signatures within a Framework of Multiple Indicators to Assess and Diagnose Causes and Sources of Impairments to Aquatic Assemblages in Selected Ohio Rivers and Streams

The use and value of biological data based on assessments of indigenous aquatic assemblages have seen unprecedented interest and growth in the past 20 years (Davis and Simon, 1995). Much of this is owed to the emphasis placed on biological assessments and criteria by the U.S. Environmental Protection Agency (USEPA) and several states for evaluating the condition of surface waters as they reflect the goals of the Clean Water Act (CWA) and state water quality standards. Recent texts such as Davis and Simon (1995), Rosenberg and Resh (1999), and Simon (1999) among many others illustrate the methods and procedures used to develop consistent and reliable bioassessment approaches. However, significant skepticism remains about the diagnostic value and utility of the biological assessments and criteria despite this recent interest (Houck, 1999).