Assessing the environmental quality status in estuarine and coastal systems: Comparing methodologies and indices

Increasingly on a worldwide scale, legislation has been adopted to determine the ecological integrity of surface waters including streams, rivers, lakes, estuaries and coastal waters. An integral part of determining ecological integrity is the measurement of biological integrity, typically emphasizing analyses of plankton, benthos, macroalgae and fish. In the development of protocols for evaluating biological integrity, benthic macroinvertebrate communities are the most consistently emphasized biotic component of aquatic ecosystems. A plethora of methodologies with hundreds of indices, metrics and evaluation tools are presently available. An ecologically parsimonious approach dictates that investigators should place greater emphasis on evaluating the suitability of indices that already exist prior to developing new ones. Hence, the authors organized within the American Society of Limnology and Oceanography 2006 Summer Meeting, 4–9 June 2006, in Victoria, BC, Canada, a special session with the objective to compare methodologies, applications and interpretations existing in various countries and attempting to contribute to an improved understanding of the suitability of such approaches when using benthic communities. From the 25 contributions presented in this session, eight manuscripts were selected to be included in this special issue of Ecological Indicators including new index development, novel validation approaches, assessment of spatio-temporal applications, interpretations relative to management needs and potential adaptive management modifications to maximize the robustness, sensitivity, and representativeness of environmental information conveyed to management.