Results 221 to 230 of about 3,720 (265)

Influence of large woody debris on sediment scour at bridge piers

International Journal of Sediment Research, 2011
Abstract Large woody debris (LWD) reduces the flow area, deviate the flow and increases the velocity in correspondence of the bridge pier, therefore increases the maximum scour hole depth and accelerates sediment removal. Logs and drifts accumulated on bridge piers are of different dimensions.
PAGLIARA, STEFANO, Carnacina I.
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Exploration on the Large Woody Debris's Influence on the River Ecological Health

2012 International Conference on Biomedical Engineering and Biotechnology, 2012
The important indication of a healthy river are good water quality, smooth channel for water and sediment and the stable eco-system. The attention is paid to the relation between a healthy river and large woody debris(LWD), the contribution of LWD to the healthy river is summarised.
Bing Tan, Dao-han Wang, Si-jing Feng
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Transport and deposition of large woody debris in streams: a flume experiment

Geomorphology, 2001
Abstract Large woody debris (LWD) is an integral component of forested streams of the Pacific Northwest and elsewhere, yet little is known about how far wood is transported and where it is deposited in streams. In this paper, we report the results of flume experiments that examine interactions among hydraulics, channel geometry, transport distance ...
Christian A Braudrick, Gordon E Grant
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LARGE WOODY DEBRIS IN URBAN STREAM CHANNELS: REDEFINING THE PROBLEM

River Research and Applications, 2011
ABSTRACTLarge woody debris (LWD) is an important ecological element in rivers and streams. Despite its importance, LWD is often removed from urban stream channels for flood control or road maintenance purposes, an approach with high economic and ecological costs and one that is largely unsuccessful. We propose an approach to conserve LWD in channels by
Lassettre, N. S., Kondolf, G. M.
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Field measurements of drag coefficients for model large woody debris

Geomorphology, 2003
Woody debris in rivers can be a significant source of roughness and consequently influences flow at both the local and reach scale. In order to develop a better quantitative understanding of the interaction between wood in rivers and stream flow, we thus performed a set of field measurements of the drag on model woody debris for conditions that prevail
Bretagne Hygelund, Michael Manga
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LARGE WOODY DEBRIS JAMS, CHANNEL HYDRAULICS AND HABITAT FORMATION IN LARGE RIVERS

Regulated Rivers: Research & Management, 1996
Field surveys document the accumulation of large woody debris (LWD) into structurally distinctive jam types in the alluvial channel of the Queets River on the Olympic Peninsula of north west Washington. Calculations, field observations and historical evidence show that these jams can form stable structures controlling local channel hydraulics and ...
TIMOTHY B. ABBE, DAVID R. MONTGOMERY
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Large Woody Debris and Land Management in California’s Hardwood-Dominated Watersheds

Environmental Management, 2005
Although large woody debris (LWD) has been studied extensively in conifer-dominated watersheds, relatively little is known about LWD in hardwood-dominated watersheds. Field surveys of 32 hardwood-dominated stream reaches in northern coastal California revealed that levels of LWD varied with land ownership and that living trees strongly influenced ...
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The Snag Bag: a new method for sampling macroinvertebrate communities on large woody debris

Hydrobiologia, 1999
La Trobe University Faculty of Science, Technology and Engineering Murray Darling Freshwater Research CentreMDFRC item.Sampling macroinvertebrate communities from natural snags (large woody debris) is difficult, particularly in southeastern Australia where the predominant river red gum snags are very large and heavy. This makes removal of natural snags
Growns, J. E., King , A. J., Betts, F. M.   +2 more
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Dynamic model for constriction scour caused by large woody debris

Earth Surface Processes and Landforms, 2002
AbstractLarge woody debris (LWD) can have a significant impact upon local channel morphology by creating scour pools and zones of reduced shear stress in which sediment is deposited. It is important to predict scour depths associated with LWD, as it is becoming increasingly common for debris to be added into river channels to improve sediment retention
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Distribution and hydraulic significance of large woody debris in a lowland Australian river

Hydrobiologia, 1996
The line-intersect technique was used to measure the loading of large woody debris in a 1.8 km reach of the Thomson River, Victoria (catchment area of 3540 km2). A debris census (measuring every item present) was done over 0.775 km of this reach. The transect technique over-estimated the actual loading revealed by the census.
Christopher J. Gippel, Brian L. Finlayson, Ian C. O'Neill   +2 more
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