A multimetric index using macroinvertebrate data collected with artificial substrates

We developed a multimetric index for macroinvertebrate data collected with multi-plate artificial substrates and employed it to assess the ecological health of several first through third order degraded/stressed streams on the upper South Carolina coastal plain. The multimetric index incorporated three classes of metrics: community structure (total taxa richness and number of Ephemeroptera, Plecoptera, and Trichoptera taxa), community balance (% Tanytarsinsi, % Ephemeroptera, % Trichoptera, and a taxonomic similarity index), and community function (total density and a functional group similarity index). Scores for each metric were based on comparisons with undisturbed streams. The index accurately separated both chemically polluted and physically degraded streams-from undisturbed streams and accurately depicted the temporal recovery of two streams that formerly received heated water.