Testing Bioassessment Metrics: Macroinvertebrate, Sculpin, and Salmonid Responses to Stream Habitat, Sediment, and Metals
- Cite this article as:
- Mebane, C.A. Environ Monit Assess (2001) 67: 293. doi:10.1023/A:1006306013724
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The purpose of this article is to report onthe testing of responses of multimetricmacroinvertebrate and habitat indices to commondisturbances to streams: stream habitat alteration,excessive sediment, and elevated metalsconcentrations. Seven macroinvertebrate community metricswere combined into a macroinvertebrate biotic index(MBI), and 11 channel morphology, riparian, andsubstrate features were combined into a habitat index. Indices were evaluated by comparing the habitatresults to fish population surveys and comparing themacroinvertebrate results to habitat ratings, percentfine sediments measured by Wolman pebble counts, andcopper concentrations. Macroinvertebrate scoresdecreased with increasing percentages of finesediments measured either across the bankfull orinstream channel widths. Macroinvertebrate scoresdecreased with increasing copper. One metric,richness of Ephemeroptera, Plecoptera, and Trichoptera(EPT) taxa, was more responsive to both copper andsediment than was the multimetric MBI. Habitat scorescorresponded well with the age class structure ofsalmonids, but not with that of benthic sculpins. Both salmonid and sculpin age classes declined withincreasing percentages of fine sediments. The declinewas graded with the sculpin age classes, whether finesediments were measured across the instream orbankfull channel, whereas salmonids consistentlyresponded only to the instream fine sediments.