HR: 10:45h
AN: NB32C-02 INVITED     [Abstracts]
TI: Zoobenthic Indicators of Environmental Condition At Great Lakes Coastal Margins Derived From Standardized Multivariate Analyses Across Anthropogenic Stress Gradients.
AU: * Ciborowski, J J
EM: cibor@uwindsor.ca
AF: University of Windsor, Dept. Biological Sciences, Windsor, ON N9B 3P4 Canada
AU: Johnson, L B
EM: ljohnson@nrri.umn.edu
AF: University of Minnesota Duluth, Natural Resource Res. Institute 5013 Miller Trunk Hwy 55811, Duluth, MN 55811 United States
AU: Gathman, J P
EM: jpgathman@yahoo.com
AF: University of Windsor, Dept. Biological Sciences, Windsor, ON N9B 3P4 Canada
AU: Brady, V J
EM: vbrady@nrri.umn.edu
AF: University of Minnesota Duluth, Natural Resource Res. Institute 5013 Miller Trunk Hwy 55811, Duluth, MN 55811 United States
AU: Holland, J
EM: holland_jeff@yahoo.ca
AF: University of Windsor, Dept. Biological Sciences, Windsor, ON N9B 3P4 Canada
AU: Hollenhorst, T
EM: thollenh@nrri.umn.edu
AF: University of Minnesota Duluth, Natural Resource Res. Institute 5013 Miller Trunk Hwy 55811, Duluth, MN 55811 United States
AU: Schuldt, J A
EM: JSchuldt@facstaff.uwsuper.edu
AF: University of Wisconsin Superior, Biology Department, Superior, WI 54880 United States
AU: Host, G E
EM: ghost@nrri.umn.edu
AF: University of Minnesota Duluth, Natural Resource Res. Institute 5013 Miller Trunk Hwy 55811, Duluth, MN 55811 United States
AU: Richards, C
EM: crichard@umn.edu
AF: MN Sea Grant College Program, University of Minnesota Duluth 2305 East Fifth Street, Duluth, MN 55812-1445 United States
AB: We used multivariate methods to derive and map multiple indices of zoobenthic community composition across anthropogenic stress gradients at Great Lakes coastal margins (shorelines - 10 m depth). We collected up to 24 benthic samples and measured environmental characteristics in each of 150 "segment sheds", ranging from minimally disturbed (=reference) to greatly modified. "K" distinct suites of co-occurring biota from minimally stressed locations were identified using cluster analysis. Discriminant function analysis identified the environmental attributes of sample locations best distinguishing each of the suites (=habitat types). Benthic community data of all samples from each habitat type (ranging across the entire stress gradient) were individually ordinated. The benthic taxa best characterizing the ends of each stress gradient were used to create a gradient-specific biotic index with a standardized scale (0=minimum, 100=maximum stress) for each habitat type, providing a stress-specific score for each sample. Contour surface analysis of mapped sample-specific scores shows the spatial pattern and limits of the overall biotic response to stress, independently of habitat type. The spatial concordance between biotic index scores and environmental stress can indicate the degree to which equivalent-to-reference conditions exist in a particular area.
DE: 1803 Anthropogenic effects
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly