Tracking eutrophication through a series of Kettle Lakes in agricultural Indiana

Chain O' Lakes State Park, located in northern Indiana, consists of nine interconnected lakes and four satellite lakes, with depths that range from 1 to 20 m. Water entering the park flows from east to west. Park managers have reported increasing cyanobacteria blooms throughout the last decade, which has resulted in periodic closure of on-site recreational facilities. Park managers are concerned about the impact on the lake ecosystems and tourism to the park.;Chain O' Lakes State Park is bordered by farmland in the extreme northeast and southwest corners of the park, and has a corrections facility in the eastern-most section of the park. In addition to fertilizer runoff (from agriculture) additional nutrient loading may be coming from the previously non-compliant on-site sewage treatment plant associated with the corrections facility.;In the spring of 2013, plankton samples were collected from each lake and indicated that the flora were dominated by species indicating elevated nutrient levels. Diatom species indicative of higher phosphorus levels tended to be greatest in the eastern lakes, generally decreasing through the chain westward. Results from sediment cores collected from each of the interconnected lakes shows increased signs of eutrophication in more recent sediments, and indicates rapid introduction of nutrients.;This project is designed to explore the impact of eutrophication through a chain of interconnected lakes, and the impacts of human development and agriculture on the system of lakes over the last two centuries. We have analyzed a series of diatom assemblages from short cores taken from each lake in the system. We ultimately intend to compare the timing of eutrophication within individual systems as a means of exploring the influence of lake hierarchy on nutrient cycling in a flow-through system.