State Water Resources Research Institute Program
Project ID: 2008IN248B
Title: Hydrological Controls on Nitrate and Carbon Delivery to Streams in Artificially Drained Landscapes of the Midwest
Project Type: Research
Start Date: 3/01/2008
End Date: 2/28/2009
Congressional District: 7
Focus Categories: Solute Transport, Surface Water, Hydrology
Keywords: Nitrate, Carbon, Tile drain, Matrix flow, Overland flow, Macropore flow
Principal Investigators: Vidon, philippe Gilles (Indiana Univ, Purdue Univ, Indianapolis); Vidon, philippe Gilles (Indiana Univ, Purdue Univ, Indianapolis)
Federal Funds: $ 14,992
Non-Federal Matching Funds: $ 31,458
Abstract: Understanding the processes controlling the delivery of nitrogen and carbon to streams in artificially drained landscapes of the Midwest is of critical importance to developing comprehensive nutrient management strategies at the watershed scale. Most nutrient and carbon losses in artificially drained landscapes of the Midwest occur during precipitation events through tile drain flow and overland flow. In addition, recent research has identified preferential flow through soil macropores as an important export mechanism contributing to tile drain flow. There is nevertheless a lack of empirical data documenting the relative importance of overland flow (OLF), matrix flow (MF) and preferential flow through soil macropores (PF) on nitrogen and dissolved organic carbon (DOC) losses to streams. For this project, the PI (Vidon) will measure the relative importance of OLF, MF and PF during 3-4 storms over a one-year period in an artificially drained Midwestern watershed, and will identify the changes in the nature of in-stream nitrogen (nitrate, ammonium, total Kjeldahl nitrogen (TKN)) and DOC (aromaticity) during storms. The work will take place in a small first order watershed, which is continuously monitored by the U.S. Geological Survey as part of the National Water Quality Assessment Program (NAWQA) for the White River, Great, and Little Miami River Basins. Water quality data will be collected in precipitation and at 2-4 hour intervals during storms in overland flow, tile flow and the stream. The PI will use a two phase (tile + stream) multi-tracer (chloride, cation, oxygen-18) approach to independently estimate the relative importance of tile drain flow, overland flow, precipitation and seepage in the stream, and the relative importance of matrix flow and preferential flow through soil macropores in tile flow. The potential of DOC and DOC specific UV absorbance (SUVA) as potential hydrologic tracers to identify water sources in a watershed context will also be evaluated.
By providing a direct quantification of the relative importance of each water delivery pathway to N and C transport to streams for a variety of storms and crop development conditions, this project will provide an increased understanding of the processes controlling N and C delivery to streams, and provide tools to better target best management practices (BMP) to minimize the impact of agriculture on raw rural water quality in the Midwest. The proposed project will promote the collaboration between USGS (Frey, Baker) and university (Vidon) scientists on significant national water resources issues. This project will also assist in the training of water scientists by involving graduate and undergraduate students in research and by supporting the research of Dr. Vidon (early career scientist, PhD 2004).
Progress/Completion Report, PDF