Channel geometry ; Discriminant analysis ; Geomorphometry ; Meander ; Model ; Statistics ; Streams ; United States
A suite of 40 morphometric variables has been measured on 57 sections of freely meandering channels from 33 rivers. These objective variables are computed from digitized traces of the channel centerline and include measures of sinuosity, meander
wavelength, curvature moments, meander asymmetry, and pattern irregularity. Principal components analysis reveals that morphological variations between freely meandering streams can be resolved into four factors related to meander wavelength, meander
irregularity, sinuosity, and large-scale wandering of the meander axis.
Channel geometry ; Fluvial processes ; Meander ; Methodology ; River bed ; Stream ; United States of America
This study, which is concerned solely with single-thread channels, focuses on resolving problems in measuring the two basic properties of meander planform: the degree of meandering (normally measured by sinuosity P) and the size or scale of meanders
(typically measured by wavelength L). Most meanders are irregular and the unambiguous identification of inflection points is problematic. The main goal of this study is to present an objective method that should be capable of providing consistent
and reproducible results even when applied to the irregular and complex meanders commonly found in nature.
This paper presents the results of experiments that simulated the formation of well defined, highly sinuous meanders in a small flume using light, fine grained materials.
Coastal environment ; Indian Ocean ; METEOSAT ; Marine hydrology ; Meander ; NOAA ; Ocean atmosphere interaction ; Remote sensing ; Sea current ; South Africa
The role played by large solitary meanders on the flow of the Agulhas Current is reviewed and a tentative classification of meander types is proposed. - (AJC)
River meanders present the most frequent planform of lowland rivers. Their formation on poljes mostly depends on flood water regime. Flooding dictates space-time zonation of meandering processes, of which the existence of active or passive phase
of planform modification depends. Studied meanders of the stream Dobravka on the Radensko polje represent an excellent example of meanders (re)formed by meandering processes (inter)actions. - (L'A.).
River meander behaviour and instability : a framework for analysis
Chaos ; Cours d'eau ; Dynamique fluviale ; England ; Géométrie hydraulique ; Modèle ; Méandre ; Royaume-Uni
Channel geometry ; Chaos ; England ; Fluvial dynamics ; Meander ; Model ; Stream ; United Kingdom
This paper examines evidence of complex behaviour and, in particular, possible operation of self-organized criticality in meandering systems, using primary evidence of a field study and also evidence from a kinematic model. The range of meander
of the full range of meander and planform behaviour. It is suggested that this new approach provides insights into meander dynamics.
This paper describes a new method to simulate river meandering within a cellular model (CAESAR). A novel technique for determining bend radius of curvature on a cell by cell basis is described, that importantly allows regional information on bend
curvature to be transferred to local points. This local curvature is then used to drive meandering and lateral erosion through 2 methods. Key difficulties are identified, including the deposition of material on point bars and cut off development
, but the method illustrates how meandering can be integrated within a cellular framework. This demonstrates the potential to produce a single model that can incorporate both meandering and braiding.
The purposes of this paper are : 1) to review current hydrodynamic concepts related to meander initiation| and 2) to provide direction for future geomorphologic investigations so that they may contribute directly to theory enhancement. The approach
Impact of groundwater flow on meandering; example from the Geul River, The Netherlands
Cours d'eau ; Ecoulement souterrain ; Erosion des berges ; Geul ; Géométrie hydraulique ; Modèle ; Méandre ; Pays-Bas
Bank erosion ; Channel geometry ; Geul ; Meander ; Model ; Netherlands (The) ; Stream ; Underground flow
The Geul River, located in the south-eastern part of The Netherlands, is a meandering river with a planform shape characterized by large loops consisting of multiple bends. The AA. evaluate the effects of groundwater flow on the shapes of meanders
as a possible explanation for the multi-bend loops, using a combined meandering-groundwater computer model. In the model seeping groundwater enhances bank erodibility.
The distribution of large woody debris (LWD) was studied along the concave outer bend of 3 meanders in the Ain River. The Ain River is a sixth-order channel dominated by a gravel-cobble bed substrate that meanders through a floodplain covered
largely by riparian forest vegetation. The total LWD deposited along concavities was most strongly controlled by meander-bend geometry. Findings from this study are applicable to restore alluvial forests along French rivers.
The AA. examine the meandering character of the Geul River using a numerical river meandering model. The main aim is to test and calibrate a topographic steering meander model. In this case study, special attention is paid to the incorporation
Des différences marquées dans les dimensions des méandres creusés dans la roche de la province des vallées et crêtes appalachiennes sont mises en relation avec les différences d'érodabilité relative de la roche en place. Les méandres taillés dans
des roches massives ou à lits grossiers, roches carbonatées en particulier sont plus petits que les méandres taillés dans les roches schisteuses (largeur et amplitude).