HR: 11:45h
AN: NB52B-06 INVITED     [Abstracts]
TI: Macroinvertebrate Responses to Wetland Hydrogeomorphic Classes in the Laurentian Great Lakes
AU: * Brady, V J
EM: vbrady@nrri.umn.edu
AF: Center for Water and the Environment, Natural Resources Research Institute, University of Minnesota Duluth, 5013 Miller Trunk Hwy, Duluth, MN 55811 United States
AU: Johnson, L B
EM: ljohnson@nrri.umn.edu
AF: Center for Water and the Environment, Natural Resources Research Institute, University of Minnesota Duluth, 5013 Miller Trunk Hwy, Duluth, MN 55811 United States
AU: Ciborowski, J J
EM: cibor@uwindsor.ca
AF: Department of Biological Sciences, University of Windsor, 401 Sunset AVe., Windsor, ON N9B 3P4 Canada
AU: Breneman, D
EM: dbrenema@nrri.umn.edu
AF: Center for Water and the Environment, Natural Resources Research Institute, University of Minnesota Duluth, 5013 Miller Trunk Hwy, Duluth, MN 55811 United States
AU: Hollenhorst, T
EM: thollenh@nrri.umn.edu
AF: Center for Water and the Environment, Natural Resources Research Institute, University of Minnesota Duluth, 5013 Miller Trunk Hwy, Duluth, MN 55811 United States
AB: As part of a larger research project on Great Lakes coastal wetlands, we investigated whether macroinvertebrate assemblages differ with varying amounts of lake and river influence. Wetlands were classified as open lacustrine (most exposed to wave action, no significant river influence; n=29), protected (little exposure to either wave or river influence; n=22), or riverine (influenced by a second order or larger stream, varying exposure to wave action; n=30). Macroinvertebrates were collected using dip nets in 2002 and 2003. Indirect gradient analyses revealed differences in macroinvertebrate assemblages related both to wetland type and to ecological province. Open lacustrine wetlands (characterized by larger average particle sizes, less soft sediment, and more open water) had the lowest macroinvertebrate diversity. Riverine wetlands contained more rheophilic taxa and had the highest invertebrate and vegetative diversity. Protected wetlands had intermediate invertebrate and vegetative diversity. We propose that wave action creates a harsher physical environment and limits fine sediment and organic matter accumulation, all leading to lower invertebrate diversity. Invertebrate and vegetative diversity are maximized by sediment and organic matter deposition and flow heterogeneity from connected streams. Ecoprovincal differences in macroinvertebrate assemblages may reflect regional patterns of anthropogenic activity in addition to biogeographic patterns.
UR: http://glei.nrri.umn.edu
DE: 1890 Wetlands
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly