|Shields Jr, Fletcher|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/15/2003
Publication Date: 10/7/2003
Citation: SHIELDS JR, F.D. LARGE WOOD AS A RESTORATION TOOL: I FOUGHT THE LAW AND THE LAW WON. EXTENDED ABSTRACT, PROCEEDINGS OF THE STREAMS CHANNEL PROTECTION AND RESTORATION CONFERENCE, 2003. P. 35-39.
Technical Abstract: Large woody debris structures hold promise as cost-effective stream corridor rehabilitation measures. Pre- and post construction data are presented that describe effects of habitat rehabilitation of Little Topashaw Creek, a sinuous, fourth-order sand-bed stream draining 37 km2 in northwest Mississippi. The rehabilitation project, constructed in 2000, consisted of placing 72 large woody debris structures along eroding concave banks and planting 4000 willow cuttings in sandbars. Response was measured by monitoring flow, channel geometry, physical aquatic habitat, and fish and invertebrate populations. Initially, debris structures reduced high flow velocities at concave bank toes, preventing further erosion and inducing deposition. Physical response during the first year following construction included creation of sand berms along eroding banks and slight increases in base flow water width and depth. Initial fish collections showed assemblages typical of incising streams within the region, but shifts consistent with addition of pool habitats and debris were observed. Progressive failure of the structures and renewed erosion were observed during the second year after construction. Factors involved in LWDS failure included simplification of the LWD matrices due to breakage and decay, scour of sediments deposited within the structures, and failure of earth anchors.