Effectiveness of Floating Islands to Reduce Suspended Solids and Nutrients in Shallow Prairie Pothole lakes - Lake Titlow Case Study
Location
CSU Ballroom
Start Date
20-4-2015 2:00 PM
End Date
20-4-2015 3:30 PM
Student's Major
Chemistry and Geology
Student's College
Science, Engineering and Technology
Mentor's Name
Bryce Hoppie
Mentor's Email Address
bryce.hoppie@mnsu.edu
Mentor's Department
Chemistry and Geology
Mentor's College
Science, Engineering and Technology
Description
Strong and persistent winds often cause pollution in shallow lakes by resuspending excessive amounts of lake bottom sediment and buried nutrients. Artificial floating islands (of wetland flora) are commonly used to improve water quality in ponds by suspending plants that remove nutrients directly from the water. To test the potential for floating islands to limit sediment resuspension and improve water quality in typical prairie pothole lakes, six experimental and two control models of Lake Titlow, Sibley County, Minnesota, were constructed. Paired scale models of shallow lakes, one with floating islands and one without, were subjected to low, medium and high wind velocities during three separate tests of nine days each. Water quality parameters measured in the models included suspended solids, total phosphorus, and chlorophyll-a. Results demonstrate that the floating islands produce an exponential reduction in suspended solids at medium and high wind velocities relative to the models without islands. The floating island models also experienced reductions in total phosphorus at low wind velocities that exceeded 100% while medium and high velocity reductions were greater than a factor of four. The reduction of chlorophyll-a in the models with floating islands was measured at 92% at low velocities with reductions up to 770% at higher velocities. Consequently, the results of this research imply that floating islands hold the potential to ameliorate the negative effects of strong and persistent winds on shallow lakes.
Effectiveness of Floating Islands to Reduce Suspended Solids and Nutrients in Shallow Prairie Pothole lakes - Lake Titlow Case Study
CSU Ballroom
Strong and persistent winds often cause pollution in shallow lakes by resuspending excessive amounts of lake bottom sediment and buried nutrients. Artificial floating islands (of wetland flora) are commonly used to improve water quality in ponds by suspending plants that remove nutrients directly from the water. To test the potential for floating islands to limit sediment resuspension and improve water quality in typical prairie pothole lakes, six experimental and two control models of Lake Titlow, Sibley County, Minnesota, were constructed. Paired scale models of shallow lakes, one with floating islands and one without, were subjected to low, medium and high wind velocities during three separate tests of nine days each. Water quality parameters measured in the models included suspended solids, total phosphorus, and chlorophyll-a. Results demonstrate that the floating islands produce an exponential reduction in suspended solids at medium and high wind velocities relative to the models without islands. The floating island models also experienced reductions in total phosphorus at low wind velocities that exceeded 100% while medium and high velocity reductions were greater than a factor of four. The reduction of chlorophyll-a in the models with floating islands was measured at 92% at low velocities with reductions up to 770% at higher velocities. Consequently, the results of this research imply that floating islands hold the potential to ameliorate the negative effects of strong and persistent winds on shallow lakes.
Recommended Citation
Hunt, Kelly. "Effectiveness of Floating Islands to Reduce Suspended Solids and Nutrients in Shallow Prairie Pothole lakes - Lake Titlow Case Study." Undergraduate Research Symposium, Mankato, MN, April 20, 2015.
https://cornerstone.lib.mnsu.edu/urs/2015/poster_session_B/22
