EUTROPHICATION IN IOWA LAKES AND WETLANDS

  Matt Hoffert and Maureen E. Clayton

   Nutrient loading is a major problem in Iowa’s lakes and wetlands due to agricultural runoff from rural watersheds.  High nutrient levels result in summer algae blooms which deplete the available oxygen and lower the overall water quality.  We examined chlorophyll a concentrations in order to determine the levels of phytoplankton present in Silver Lake and the Beaver Valley Wetlands.  The chlorophyll concentrations in the wetlands increased over the summer but remained noticeably lower than that of Silver Lake.  Compared to years past, Silver Lake had relatively low and constant concentrations of chlorophyll a.  This is likely due to differences in the amount and timing of rain events, not to a change in land use practices in the watershed.  Future studies should closely compare nutrient levels to chlorophyll a levels to investigate this hypothesis.

This research was supported by the Roy J. Carver Charitable Trust and the Iowa Space Grant Consortium.