Water Resources Research Act Program

Details for Project ID 2007IN221B

Quantification of sediment nutrient interaction as affected by drainage ditch management

Institute: Indiana
Year Established: 2007 Start Date: 2007-03-01 End Date: 2008-02-28
Total Federal Funds: $18,639 Total Non-Federal Funds: $37,284

Principal Investigators: Indrajeet Chaubey, Laura Bowling

Project Summary: Even though excess nutrients from agricultural lands are a principal water quality concern in many parts of the Midwestern United States, the in-stream movement and transport of nutrients and their interaction with benthic sediments are not well understood. This is especially true for agricultural drainage ditches where the role of biotic and abiotic processes controlling nutrient dynamics at the sediment-water interface is not clear. The objectives of this study will be to quantify the impact of ditch management strategy on: (1) spatial and temporal variability in easily exchangeable N and P, and P buffering capacity; (2) equilibrium between sediments and water column P; and (3) variation in stream nutrient retention efficiency. The study will be conducted in Hoagland Watershed located in the Wabash River basin. The study watershed typifies rural, mixed-use watersheds in the eastern Corn Belt. Hoagland Ditch drains into the Tippecanoe River (which is dammed to create Lake Shafer, a popular recreational lake), and then into the Wabash River. The local economy surrounding Lake Shafer is dependent on tourism, and thus on the maintenance of acceptable water quality. Two ditch management strategies will be assessed: dredging versus no dredging and vegetated versus nonvegetated ditch channels. This study will use sediment nutrient extractions, and short-term nutrient injections to measure sediment equilibrium P concentration (EPCo), easily exchangeable N and P, P sorption index, and net uptake length for N and P. The results will enable a better understanding of how drainage ditch management affects form, timing, and magnitude of nutrient transport and assimilation and will be useful in improving currently available in-stream models of nutrient transport. The research findings will be disseminated through journal articles, conference presentation, direct meeting with various state agencies, and a web-site created for this project. The project will support a M.S. level thesis research, will contribute to Ph.D. level thesis research and will provide undergraduate training.