USING MULTIPLE TAXONOMIC GROUPS TO ASSESS LAND USE IMPACTS IN WETLANDS OF THE MUSKEGON RIVER WATERSHED.

C.A. Parker, V.L. Lougheed, and R.J. Stevenson. Department of Zoology, Michigan State University, East Lansing, MI, 48824

To determine how biotic communities are influenced by land-use, twenty marshes in the Muskegon River watershed (MRW) (Michigan, USA) were visited in 2001 and sampled for water quality parameters and the structure of the macrophyte, periphyton and zooplankton communities. This is part of a 3 year assessment project which will ultimately study 100 wetlands in the MRW; however, preliminary results are reported here. Reference and impacted wetlands were characterized with respect to predominant land use in their subwatersheds, as well as nutrient criteria. Tolerant taxa of macrophytes (e.g. Potamogeton pectinatus, the exotic Myriophyllum spicatum) were more abundant (>75%) in impaired sites, while representing a much lower percent cover (<10%) in reference sites. Similarly, the zooplankton community was reflective of the ecological quality of the wetlands and these data were summarized using a zooplankton index of wetland quality developed for the Great Lakes basin. Diatom community structure from both macrophyte and sediment surfaces will also be used to assess wetland quality. Finally, data from all three biotic groups were synthesized into web-based environmental report cards as part of a secondary objective to increase public awareness of the intrinsic values of the MRW.