|Shields Jr, Fletcher|
Submitted to: Annual Water Resources Conference
Publication Type: Abstract Only
Publication Acceptance Date: May 20, 2002
Publication Date: November 3, 2002
Citation: Shields, F.D., Jr., Dabney, S.M. Vegetative side inlets to control riparian zone gullies. American Water Resources Association 2002 Annual Water Resources Conference Proceedings. 2002. Abstract p. 253. Technical Abstract: Riparian zones adjacent to incising streams are often dissected by gullies that increase watershed sediment yield, degrade stream habitats, and adversely impact adjacent floodplain land uses. Current practice for gully control involves blocking the gully with an earthen embankment and installing a drainage structure. Measures involving native vegetation would be more attractive for habitat recovery and economic reasons. To test the hypothesis that switchgrass (Panicum virgatum L.) hedges planted every 0.5 m vertically within a gully would control erosion, we established a series of such hedges in six riparian gullies at field margins adjacent to Little Topashaw Creek, Mississippi. After two years we tested the stability of one hedge-lined gully ~ 10 m by 3 m deep in sandy, highly erodible soil by pumping creek water to create artificial runoff events with trapezoidal-shaped hydrographs that produced specific discharges similar to those measured during natural runoff events. Flow depths were generally < 0.25 m and flow velocities were generally < 0.8 m s-1. Results indicated that the hedges can stabilize gullies under the flow conditions tested where they can be established with a vertical spacing of 0.5 m, but not when the vertical interval is as great as 2 m.