|Shields Jr, Fletcher|
Submitted to: International Journal of Sediment Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 1, 1999
Publication Date: N/A
Interpretive Summary: Many stream corridors in agricultural watersheds suffer from problems of accelerated erosion and sedimentation. Traditional measures for controlling bank erosion in deeply incised streams generally use costly structures. Although felled trees and woody vegetation have long been used to control stream erosion, scientifically-based guidelines for their use are scarce. Recent field and laboratory research has investigated effects of woody vegetation on the ability of channels to convey water, on patterns of erosion and sediment deposition, and on the durability and reliability of like flood control levees and streambank protection revetments. Relevant literature dealing with recent advances in this area is reviewed and summarized. The review will provide a foundation for future research and demonstration in uses of vegetation and woody debris to rehabilitate stream corridors damaged by erosion and sedimentation.
Technical Abstract: Large woody debris and woody vegetation can exert a major influence on channel hydraulics and morphology, particularly in smaller (< 30 m wide) streams. Although debris and vegetation have long been used for channel erosion and sedimentation control, scientifically-based guidelines for designers are scarce. From an engineering standpoint, much is unknown about the effects of vegetated boundaries on streams. Recent advances in understanding vegetative effects on flow and sediment transport are reviewed. The effects of vegetation on the flow field leads to enhanced deposition within and adjacent to vegetated zones, and possibly erosion elsewhere. Site factors including soil moisture and texture must be carefully evaluated when designing vegetative treatments.