Natural Resources, School of


Date of this Version



A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science Major: Natural Resources Sciences Under the Supervision of Professor John C. Holz Lincoln, Nebraska May, 2011 Copyright 2011 Jennifer L. Swanson


Eutrophication has been the most challenging global threat to the quality of our freshwater resources (Likens, 2010). Reversing the effects of eutrophication can be difficult and takes a great deal of time and money. A hypereutrophic Midwestern reservoir underwent a restoration from 2000-2002, which added a sediment basin at the inlet, three islands, five rock jetties, and the removal of rough fish. The primary objective of this study was to determine changes in the benthic macroinvertebrate community in response to the restoration. Water quality and benthic macroinvertebrate samples were collected once per month in June, July, August, and September in 2009; benthic invertebrate densities were compared from: i) 1970 and 2003 to determine if the macroinvertebrate community was reset to its original composition, ii) 1970 and 2009 to determine the impact of the restoration and iii) 2003 and 2009 to determine if the community has remained the same or if it has changed. Benthic invertebrate mean densities were significantly different between 1970 and 2003, and between 1970 and 2009. However, they were not significantly different between 2003 and 2009. Overall, water quality seemed to have had no effect on the benthic community, whereas the restoration increased the diversity of the benthos by increasing the amount of habitat available.