|Lerch, Robert - Bob|
Submitted to: North American Agroforestry Conference
Publication Type: Abstract Only
Publication Acceptance Date: 5/11/2009
Publication Date: 5/31/2009
Citation: Drost, C.C., Berges, S.V., Lerch, R.N., Schultz, R.C. 2009. Streambank Erosion Rates of Small Missouri Streams [abstract]. North American Agroforestry Conference, May 31-June 3, 2009, Columbia, Missouri. 2009 CD-ROM. Interpretive Summary:
Technical Abstract: As a nonpoint source of pollution, sedimentation of surface waters in the United States is a significant environmental concern. Investigating land use impacts on streambank erosion rates may lead to the development of improved management practices or provide the basis for targeting the placement of management practices to mitigate this problem. The primary objective of this research was to determine the effect of stream channel size, adjacent land use, and season on streambank erosion rates. Study sites were established in 2007 and 2008 within Crooked and Otter Creek watersheds, two claypan watersheds located in Northeast Missouri. Detailed site information was recorded, including eroded streambank length, soil descriptions, gullies, debris dams, cattle access areas, and point bars. A factorial experimental design was implemented with four land uses (riparian forest, forest, pasture, and cropped) and three stream orders (1st, 2nd, 3rd). Each treatment was replicated three times for each stream order, except for the cropped 3rd order treatment as only one suitable treatment could be found. Erosion pins were installed based on bank height and length at each site to measure bank erosion/deposition rates. The effect of different seasons was assessed by measuring the length of the exposed pin three times per year (March, July, November). Statistical analyses will be performed to determine the effect of stream order, land use, and season on erosion rates. Based on field observations to date, winter 2008 had the highest erosion rates, regardless of stream order or adjacent land use. Frequent and large runoff events from April through September 2008 resulted in deposition rather than erosion, despite having much greater stream discharge than the winter 2008 runoff events.