Spatial and temporal variability of diatom and macroinvertebrate communities: How representative are ecological classifications within a river system?

▸ We examine variability of ecological classifications of stream diatoms and macroinvertebrates. ▸ Ecological condition is different among tributaries and main channel. ▸ Ecological classifications differ among the two taxonomic groups. ▸ Diatom classifications are temporally variable. ▸ Ecological condition is weakly related to stressor gradients.