Fluvial Geomorphology and Nutrient Processing in Low-Order
Streams in Midwestern Tile-Drained Agricultural Landscapes
Bruce
Wilson, Professor
Andy Ward, Professor, The Ohio State University
John Nieber, Professor
Gary Sands, Associate Professor
Brad Hansen, Senior Scientist
Tim Sundby, Graduate Student
Funding Source
U.S. Department of Agriculture
Objective
The overall goal of the study is to quantify the extent
that agricultural drainage ditches can reduce nitrogen loading
and
to identify management practices that increase nitrogen removal
while maintaining economic viability. Objectives in Minnesota
are to:
- Gather geomorphoric data for drainage ditches and
natural streams,
- Develop regional curves to describe the characteristics
of the Objective 1 data set, and
- Evaluate the usefulness
of the Ohio Two-Stage Drainage Ditch for Minnesota conditions.
Need or Impact
The Ohio State University has investigated the
role of fluvial processes in establishing features in drainage
ditches that
correspond to those observed in natural channels. Of particular
importance are their conclusions that the formation of natural-channel
features is predictable and are associated with high tile
discharge events. Most of their work has been done using drainage
ditches
in Ohio. The University of Minnesota will be investigating
the applicability of their approach for Minnesota conditions.
Project
Status
A screening tool for determining the stability
of drainage ditches has been proposed, and its usefulness
is being evaluated. The
screening tool includes both physical and biotic characteristics
of drainage ditches. The geomorphologic characteristics of
many Minnesota drainage ditches have been measured. Regression
analyses
have been performed to develop regional curves. The usefulness
of these curves is currently being evaluated within the framework
of the Ohio two-stage design.
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