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Prediction of alluvial channel pattern of perennial rivers

Prediction of alluvial channel pattern of perennial rivers
Braided channel ; Carrying capacity ; Channel geometry ; Discharge ; Flood ; Floodplain ; Fluvial processes ; Forecast ; Meander ; River bed
This paper attempts to predict the individual channel pattern of perennial rivers from independent boundary conditions defined by the river discharge and the bed material. The analysis is limited to wide alluvial floodplains, which do not restrict
the evolution of braided rivers. The analysis is further restricted to streams that are in dynamic equilibrium and that show neither rapid accretion nor incision.

Sediment transport from the glacier zone, Central Asia

All available data on suspended sediment concentration and sediment discharge for Central Asian rivers have been used to estimate the small grained sediment discharge from glaciated areas. Glacial streams discharge the bulk of suspended material
during the period of intensive melting (July to September). There is a good exponential relationship between sediment concentration (or sediment discharge) and air temperature over glaciers. Yearly sediment run-off for glacial rivers in the Pamir and Tien

Vztahy mezi kolisanim srazek a odtoku na uzemi CSR podle rad mesicicnich hodnot. (Relation between variations of precipitation and discharge rates on the territory of the C.S.R. according to series of monthly values)

Vztahy mezi kolisanim srazek a odtoku na uzemi CSR podle rad mesicicnich hodnot. (Relation between variations of precipitation and discharge rates on the territory of the C.S.R. according to series of monthly values)
The study presents the results of analysis of precipitation and discharge rates in C.S.R. of spatial monthly sums in Bohemia (mean monthly discharge rates of the Elbe at Decin in the period of 1877-1981) and in Moravia (discharges rates
of the Morava river at Moravsky Jan in the period 1895-1980). Analysis was performed using the methods of autocorrelation analysis, dynamic and numerical band pass filtering. (MS).

Small water bearing values and their periods in the rivers of the Czech Socialist Republic

Small water bearing values and their periods in the rivers of the Czech Socialist Republic
The using of discharge rate to 36 % of the long term average discharge made possible to recognize a different balance of water circulation in the river basins of CSR. The properties of the natural environment of drainage are decisive for total

Recent variation in reach-scale bankfull discharge in the Lower Yellow River

Recent variation in reach-scale bankfull discharge in the Lower Yellow River
Carrying capacity ; China ; Discharge ; Huang He ; Hydraulic works ; Stream
In this study, a general method to calculate cross-sectional bankfull discharge using the simulated stage-discharge relation is outlined briefly, and an integrated method is then proposed for estimating reach-scale bankfull discharge along the Lower
Yellow River (LYR). The proposed method integrates a geometric mean based on the log-transformation with a weighted average based on the spacing between 2 consecutive sections, which avoids the shortcomings of previous methods. The post-flood reach-scale
bankfull discharges in 3 different channel-pattern reaches of the LYR were estimated annually during the period from 1999 to 2010 using this method, based on surveyed post-flood profiles at 91 sedimentation sections and the measured hydrological data at 7
hydrometric sections. Finally, empirical relationships for different reaches in the LYR were developed between the reach-scale bankfull discharge and the previous four-year average discharge and incoming sediment coefficient during flood seasons.
[b2] Yellow River Inst. of Hydraulic Research, YRCC, Zhengzhou, Chine

Discrimination of channel patterns for alluvial rivers based on the sediment concentration to water discharge ratio

Discrimination of channel patterns for alluvial rivers based on the sediment concentration to water discharge ratio
Braided channel ; Channel geometry ; China ; Discharge ; Discriminant analysis ; Meander ; Model ; River bed ; Stream
Based on data from 107 Chinese alluvial rivers, a study has been made to relate river channel patterns to the water discharge ratio (ζ) index. These rivers can be classified as four channel patterns, i. e., braided, low concentration meandering
, hyperconcentration meandering and island. It was found that, when mean annual water discharge (Q) is given, the ζ index for hyperconcentration meandering rivers is the highest, for braided rivers the second, for low-concentration meandering rivers the third
, and for island rivers the lowest. A discriminating model has been proposed for the above four channel patterns, based on the relationship between ζ and Q. Three threshold lines between the four channel patterns are well identified. Of the 107 Chinese rivers

Spatial and temporal variability of water discharge in the Yellow River Basin over the past 60 years

Spatial and temporal variability of water discharge in the Yellow River Basin over the past 60 years
Annual variation ; China ; Climatic change ; Discharge ; Huang He ; Human impact ; Ocean atmosphere interaction ; Space time ; Watershed
Water discharge data of the Yellow River over the past 60 years was analyzed using the continuous wavelet transform (CWT) and Mann-Kendall (MK) test methods to identify spatial and temporal variation patterns. Potential connections between water
discharge in the Yellow River Basin and El Niño/Southern Oscillation (ENSO) were also examined by the cross wavelet and wavelet coherence methods. The changes in water discharge were found to be influenced by both climate changes and human activities. Before
1970 the change in water discharge was positively related to precipitation variations in the river basin, but after 1970 the decrease in water discharge has been largely caused by various human activities including constructions of reservoirs, water

Morphological and hydrological characteristics of some allochtonous river channels, Western Deccan Trap Upland region, India

Morphological and hydrological characteristics of some allochtonous river channels, Western Deccan Trap Upland region, India
Relations are established between various channel morphologic variables for the Upland rivers of Western Deccan Trap region, using seventy-three sites, three channel categories and ten parameters. An attempt to relate morphologic variables
to discharge, reveals that the maximum monsoon discharge (Q max) has a very strong influence on the channel width and gradient, rather than the mean monsoon discharge (Q mm).

Predicted wetted width in any river at any discharge

Predicted wetted width in any river at any discharge
Channel geometry ; Cross section ; Discharge ; Ecosystem ; Habitat ; Hydrology ; Model ; New Zealand ; Stream
In this paper, patterns in at-a-station hydraulic geometry are analysed using observed field data on width and discharge together with mapped catchment characteristics such as catchment area and climate. The aim of the paper is to estimate
the parameters for the at-a-station relationship between discharge and width at ungauged sites, and the variation around this relationship. The purpose of this work was to produce a method for predicting width over a range of discharges for applications

Bankfull discharge in mountain streams : theory and practice

Bankfull discharge in mountain streams : theory and practice
Carpathian Mountains ; Discharge ; Flood ; Methodology ; Mountain ; Poland ; Riparian vegetation ; Stream
The results are presented of an investigation of bankfull discharge in two Polish Carpathian streams : Skawica and Krzyworzeka. Existing definitions of river bankfull were reviewed and applied in tests carried out on selected cross-sections
of the streams. The Woodyer method was given special attention, with a correspondingly detailed survey of plants characterizing river benches. Riley's bench index method and the methods of Williams, Wolman, Schumm and Brown, and Woloszyn were tested. The report
concludes that bankfull discharge value for a mountain stream should not be reported as a single number, but rather as a range of discharges within which one could expect the bankfull value to lie.

Hydrologic control of waveforms on small meandering rivers

Hydrologic control of waveforms on small meandering rivers
Aerial photography ; Autocorrelation ; Bank erosion ; Canada ; Channel geometry ; Hydrology ; Meander ; Ontario ; Photointerpretation ; Pic discharge ; Stream
and statistical analysis of curvature series based on autocorrelation and spectral analysis. This paper argues that the scaling of wavelengths with discharge can be considered a strong factor controlling planform evolution on some small meandering river systems
Small river channels within the Humber Basin of Southern Ontario exhibit irregular meandering patterns. Recent changes in river planform are assessed through a bi-temporal comparison of channel planform using orthorectified aerial photography

Channel change, bankfull and effective discharges on a vertically accreting, meandering, gravel-bed river

Channel change, bankfull and effective discharges on a vertically accreting, meandering, gravel-bed river
The focus in this paper is on the lower reaches of the Waipaoa River, New Zealand, and their response to a massive increase in suspended-sediment load (and only a small, concurrent increase in water discharge) following deforestation. The AA. use
field data to characterize the channel, and determine the bankfull discharge at different locations throughout the reach by routing known discharges through a one-dimensional flow model.

Some preliminary latent variable models of stream sediment and discharge characteristics in Geomorphological models. Theoretical and empirical aspects.

Some preliminary latent variable models of stream sediment and discharge characteristics in Geomorphological models. Theoretical and empirical aspects.
The primary purpose of this paper is to illustrate a methodology which can evaluate hypotheses about relations between latent variables and measurable indicators. This methodology is exemplified by an analysis of water and sediment discharge
characteristics in the Missouri River basin.

Response of delta sedimentary system to variation of water and sediement in the Yellow River over past six decades

Response of delta sedimentary system to variation of water and sediement in the Yellow River over past six decades
Channel geometry ; China ; Delta ; Discharge ; Huang He ; Human impact ; Sediment budget ; Sedimentation ; Silting
In order to find out the variation process of water-sediment and its effect on the Yellow River Delta, the water discharge and sediment load at Lijin from 1950 to 2007 and the decrease of water discharge and sediment load in the Yellow River Basin
caused by human disturbances were analyzed by means of statistics. It was shown that the water discharge and sediment load into the sea were decreasing from 1950 to 2007 with serious fluctuation. The AA. discuss the channel evolvement in the lower reaches.

Increase in suspended sediment discharge of the Amazon River assessed by monitoring network and satellite data

Increase in suspended sediment discharge of the Amazon River assessed by monitoring network and satellite data
Amazonas River ; Brazil ; Discharge ; Fluvial hydrology ; Observation network ; Remote sensing ; Sediment budget ; Sediment transport ; Stream ; Suspended load
This study addresses the quantification of the Amazon River sediment budget which has been assessed by looking at data from a suspended sediment discharge monitoring network and remote sensing estimates derived from MODIS spaceborne sensor. Both
field and satellite-derived estimates of the sediment concentration of the Amazon River are combined to get an uninterrupted monthly average suspended sediment discharge from 1995 to 2007. Unlike the water discharge which exhibits a steady trend over
the same period at Óbidos (Brazil), the suspended sediment discharge increases since 1995.

The influence of contemporary flow regime on the geomorphology of the Sabie river, South Africa

The influence of contemporary flow regime on the geomorphology of the Sabie river, South Africa
Channel geometry ; Cross section ; Discharge ; Fluvial dynamics ; Inundation ; Mpumalanga ; Recurrence interval ; River regime ; South Africa ; Stream
seasonal flow regime. Stage-discharge relationships have been observed and constructed for 23 monitoring sites on the Sabie River. These have been used in conjunction with a 62-year calibrated simulated daily discharge record, to generate inundation
This paper presents the results of an investigation into the relationship between flow magnitude and frequency, and the geomorphological units of the Sabie River in the Mpumalanga Province. The river is perennial, however, it exhibits an extreme

Outline of river adjustments in small river basins in Belgium and the Netherlands since the Upper Pleniglacial in Lake, mire and river environments during the last 15.000 years.

Outline of river adjustments in small river basins in Belgium and the Netherlands since the Upper Pleniglacial in Lake, mire and river environments during the last 15.000 years.
. These adjustments are discussed and explained as water discharge fluctuations due to change in precipitation and/or evapotranspiration. In relation to the river adjustments, tentative curves of precipitation, evapotranspiration, and water discharge over the last
Small river-basins in lowland areas of Belgium and The Netherlands show four episodic river adjustments since the Upper Pleniglacial, dated at the end of the Pleniglacial/early Late Glacial and the Late Dryas, Boreal, and Subboreal/Subatlantic

Bank-full discharge of rivers

Bank-full discharge of rivers

River discharge in relation to rainfall, evapotranspiration and lithology in the Serayn River basin, central Java, Indonesia

River discharge in relation to rainfall, evapotranspiration and lithology in the Serayn River basin, central Java, Indonesia

Shifting discharge peaks in Arctic rivers, 1977-2007

Shifting discharge peaks in Arctic rivers, 1977-2007
Arctic Region ; Climatic warming ; Cold area ; Fluvial dynamics ; Global change ; Meltwater ; Peak discharge ; Stream
Here, the most recent observational records are analyzed for 19 large rivers encompassing the entire Arctic region over the period 1977 to 2007. Trends in total annual water discharge, melt month and peak month discharge are calculated
for individual systems based on records with monthly time resolution. An increase in annual discharge over the entire region is observed over the last 30 years. Melt month discharge increases considerably, whereas peak month discharge is reduced. The AA

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