Biological indicators of stream health using macroinvertebrate assemblage composition: a comparison of sensitivity to an urban gradient

Abstract

Biological indicators are increasingly being used as integrative measures of ecosystem health in streams, particularly indicators using macroinvertebrate assemblage composition. Several indicators of this type have been advocated, including biotic indices based on taxa sensitivities, richness indices and ratios of observed to expected taxa from models predicting assemblage composition in streams with little human impact (O/E scores). The present study aimed to compare the sensitivity of indicators of each of these types (all used for legislated objectives for stream protection in Victoria, Australia) to a gradient of urban disturbance in 16 streams in a small area in eastern Melbourne. The b..