HR: 1330h
AN: NB33B-10    [Abstracts]
TI: Application of State Biological Assessment Protocols to the Lower Missouri River: are any Lotic Systems Non-Wadeable ?
AU: * Poulton, B C
EM: bpoulton@usgs.gov
AF: Columbia Environmental Research Center, U.S. Geological Survey, 4200 New Haven Rd., Columbia, MO 65201
AB: Benthic ecologists have suggested that the biological condition of large rivers could be successfully evaluated with modifications of small stream bioassessments. The lower Missouri system contains a unique fauna with rare, large-river macroinvertebrate species that are difficult to sample and more poorly known ecologically. As part of an evaluation of 27 indicator metrics and their ability to detect cumulative stressors, an 812 km section of the lower Missouri was sampled with three methods in two key habitats. Among these, rock revetments were sampled with a D-frame kick net using the state of Missouri's biological assessment protocol developed for coarse substrate in riffles of wadeable streams. A total of 62 species of macroinvertebrates were collected, as compared to 72 species from artificial substrates deployed at the same locations. Ranges in values for the four core metrics included in the Missouri protocol (total taxa richness 24-42, EPT taxa richness 9-18, Missouri Biotic Index 5.89-6.33, Shannon-Wiener Index 1.60-2.77) were more comparable to data from perennial 4th and 5th order streams than the values from artificial substrate data. However, proposed biocriteria for wadeable streams in Missouri could not identify impairment levels among sites, and no longitudinal response gradient was apparent until an additional 8 metrics were included in the site scores. Utilization of semi-quantitative kick net protocols in large rivers can yield data comparable to wadeable streams if sampling is performed under specific conditions related to hydrology and insect colonization dynamics.
DE: 0345 Pollution--urban and regional (0305)
DE: 1803 Anthropogenic effects
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly