Mesohabitat-specific macroinvertebrate assemblage responses to water quality variation in mid-continent (North America) great rivers

摘要: Abstract We compared the responsiveness of macroinvertebrate assemblages to variation in water quality (ions, nutrients, dissolved metals, and suspended sediment) two mesohabitats within main channel three North American great rivers, Upper Mississippi, Missouri, Ohio. Based on about 400 paired samples, we examined benthic sampled littoral zone from surface woody snags channel. The were different all rivers. Taxa richness was much higher benthos than snags. Macroinvertebrate assemblage response weak Mississippi River, but reasons for this are unknown. analysis similarity between composition groups sites with high low concentrations variables, only slightly more sensitive chemistry snag assemblages. Results two-sample comparisons variables consistent rank correlations metrics quality. In general, there little difference habitats any river. Our simple method sampling rivers is usually easier because it does not require wading. Snag large has some limitations (e.g., natural sometimes absent, samples semi-quantitative), lack sensitivity gradients among them.