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River width computation
The objective is to compute river width on each node of a river network. The principle is to link width measured during electro-fishing operations (and available in BDMAP) with a proxy which allows a generalisation to a river network.
Usually , river width is connected to river discharge with a square-root link (Leopold et Maddock 1953; Andrews 1984; Julien and Wargadalam 1995; Jiongxin 2004; Lee and Julien 2006; Caissie 2006. The river discharge is more or less proportional to streaming surface although allometric relationships shown some regional variations (Benyahya et al., 2009). Thornton et al. (2007) found a direct square-root relationship between river width and upstream streaming surface.
Andrews, E.D. (1984). Bed-material Entrainment and Hydraulic Geometry of Gravel-Bed Rivers in Colorado. Geological Society of America Bulletin, 95, 371-378.
Benyahya, L., A. Daigle, et al. (2009). Caractérisation du régime naturel du débit des bassins versants de l’Est du Canada., INRS-ETE: 88
Caissie, D. (2006). River discharge and channel width relationships for New Brunswick rivers, Canadian technical report of fisheries and aquatic sciences/Rapport technique canadien des sciences halieutiques et aquatiques: 26
Jiongxin, X. (2004). "Comparison of hydraulic geometry between sand- and gravel-bed rivers in relation to channel pattern discrimination." Earth Surface Processes and Landforms 29(5): 645-657
Julien, P. Y. and J. Wargadalam (1995). "Alluvial Channel Geometry: Theory and Applications." Journal of Hydraulic Engineering 121(4): 312-325.
Lee, J.-S. and P. Y. Julien (2006). "Downstream hydraulic geometry of alluvial channels." Journal of Hydraulic Engineering 132(12): 1347-1352.
Leopold, L. B. and T. Maddock (1953). The hydraulic geometry of stream channels and some physiographic implications. Washington, DC, U.S. Geological Survey Professional Paper: 57.
Shreve R. 1974. Variation of mainstream length with basin area in river networks. Water Resources Research, 10, p. 1167-1177.
Thornton, E., M. Neave, et al. (2007). Hydraulic geometry in river channel networks as a method for the assessment of river condition. Proceedings of the 5th Australian Stream Management Conference. Australian rivers: making a difference., Thurgoona, New South Wales., Charles Sturt University. http://www.csu.edu.au/research/ilws/news/events/5asm/docs/proceedings/Thornton_Elizabeth_401.pdf
River network order
Strahler, Shreve, Horton, Scheidegger
Stream order
Problems in the model
This is worth thinking about !!
- Distribution of the up_catchment_area according to the strahler, shreve order
- Distribution of the op_cs_largeurlameeau linked to the strahler, shreve order
The first order stream must be different.
Calculating the density
Les densités peuvent être calculées, à un coefficient de proportionnalité près, en divisant cette proportion par la surface du tronçon, ou, dans la mesure où les tronçons sont de longueur constante, en divisant par la largeur du tronçon. Thornton et al. {, 2007 #4542} trouvent une relation puissance 0.5 entre largeur d’un cours d’eau et la surface du bassin versant amont. En règle générale, la largeur s’exprime avec la même fonction puissance 0.5 à partir du débit {Andrews, 1984 #4525; Leopold, 1953 #4538; Lee, 2006 #4539; Julien, 1995 #4540; Jiongxin, 2004 #4541} lui même proportionnel à la surface amont du bassin versant.
Thornton relation : W = 4.98 CA0.47
River width models
River width for BV Loire, Franche Comté : http://www.modul-stufen-konzept.ch/download/22092006/3_typologie_france.pdf
