SS4.05 Tribute to Thomas Frost
Date: Monday, June 10, 2002
Time: 4:15:00 PM
Location: Sidney
 
SierszenME, U.S. EPA, Duluth, USA, sierszen.michael@epa.gov
Brazner, J, C, U.S. EPA, Duluth, USA, brazner.john@epa.gov
Morrice, J, A, U.S. EPA, Duluth, USA, morrice.john@epa.gov
Trebitz, A, S, U.S. EPA, Duluth, USA, trebitz.anett@epa.gov
 
NATURAL AND ANTHROPOGENIC FACTORS INFLUENCING FOOD WEB STRUCTURE IN GREAT LAKES COASTAL WETLANDS
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We are investigating factors governing the biological organization of Great Lakes coastal wetlands. Food web analyses using stable isotope techniques verify the role of algae as an energetic foundation, and also suggest that fundamental changes occur as a result of anthropogenic disturbance. The relative importance of periphyton and phytoplankton to consumers may shift, with periphyton dominant in pristine systems and phytoplankton increasingly important with nutrient enrichment. However, natural factors such as hydrology can also impose constraints on the development of algal communities and, therefore, on food web structure. I will present analyses of coastal wetlands with a range of nutrient concentrations and with hydrologic characteristics that grade from lacustrine to riverine, and will contrast the relative importance of these natural and anthropogenic factors to food web structure.