Correction to “A general power equation for predicting bed load transport rates in gravel bed rivers”

Barry, Jeffrey J.; Buffington, John M.; King, John G.

doi:10.1029/2007wr006103

Cited by 14 publications

(16 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We first apply a power law load relation without a threshold for significant transport [e.g., Engelund and Hansen, 1967;Parker, 1990aParker, , 1990bSyvitski et al, 2000;Emmett and Wolman, 2001;Wilcock and Crowe, 2003;Goodwin, 2004;Barry et al, 2004Barry et al, , 2007Doyle and Shields, 2008;Houssais et al, 2015], which reflects Einstein, 's [1950] probabilistic philosophy regarding the nature of sediment transport.…”

Section: An Explicit Analytical Modelmentioning

confidence: 99%

The equilibrium alluvial river under variable flow and its channel‐forming discharge

et al. 2017

View full text Add to dashboard Cite

When the water discharge, sediment supply, and base level vary around stable values, an alluvial river evolves toward a mean equilibrium or graded state with small fluctuations around this mean state (i.e., a dynamic or statistical equilibrium state). Here we present analytical relations describing the mean equilibrium geometry of an alluvial river under variable flow by linking channel slope, width, and bed surface texture. The solution holds in river normal flow zones (or outside both the hydrograph boundary layer and the backwater zone) and accounts for grain size selective transport and particle abrasion. We consider the variable flow rate as a series of continuously changing yet steady water discharges (here termed an alternating steady discharge). The analysis also provides a solution to the channel‐forming water discharge, which is here defined as the steady water discharge that, given the mean sediment supply, provides the same equilibrium channel slope as the natural long‐term hydrograph. The channel‐forming water discharge for the gravel load is larger than the one associated with the sand load. The analysis illustrates how the load is distributed over the range of water discharge in the river normal flow zone, which we term the “normal flow load distribution”. The fact that the distribution of the (imposed) sediment supply spatially adapts to this normal flow load distribution is the origin of the hydrograph boundary layer. The results quantify the findings by Wolman and Miller (1960) regarding the relevance of both magnitude and frequency of the flow rate with respect to channel geometry.

show abstract

Section: An Explicit Analytical Modelmentioning

confidence: 99%

The equilibrium alluvial river under variable flow and its channel‐forming discharge

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Using equations (10) and (11), we obtained β = 2.88. Note that the correction published by Barry et al [2007] is not relevant here, as it only affects the estimation of the prefactor, which we obtained from site-specific data as follows. Many commonly used bed load equations show poor predictive performance for steep streams such as the Erlenbach [e.g., Nitsche et al, 2011;Yager et al, 2012].…”

Section: Theoretical Calculation Of the Energy Delivered To The Bedmentioning

confidence: 99%

Field measurements of the energy delivered to the channel bed by moving bed load and links to bedrock erosion

Turowski

Böckli

Rickenmann

et al. 2013

J. Geophys. Res. Earth Surf.

View full text Add to dashboard Cite

[1] Impact-driven fluvial erosion is directly related to the energy delivered to the channel bed by moving bed load. Using a novel protocol, we have measured this energy in four mountain streams in Austria and Switzerland. Similar to bed load transport rates, the energy delivered to the bed displays large scatter over several orders of magnitude even for a constant discharge. We found that only a small fraction (<1%) of the total energy available to the stream is delivered to the bed and can be used for erosive work. Empirical predictive equations can be defined for specific sites, but there is large site-to-site variability. Prediction of energy delivered to the bed using the saltation-abrasion model of bedrock erosion only provides the observed trends when measured bed load transport rates are used as input. Using an empirical transport law calibrated to the conditions at one of the study streams leads to overprediction of delivered energies by more than 2 orders of magnitude. This overprediction decreases with increasing discharge, and thus, at high discharges, better predictive results are obtained. We find a correlation between the channels' bed slope or characteristic grain sizes of the channel bed and the fraction of energy delivered to the bed of the total energy available to the stream. This observation provides a tentative link between fundamental fluvial incision processes to the stream power model family that has widely been used to model fluvial bedrock incision in landscape evolution simulations.

show abstract

“…In addition, because equations derived on the basis of field data are supposed to have a built‐in allowance for the effects of spatial variability, they should considerably improve the computation of bed load transport when compared with standard 1D equations; however, many equations based on field data are also site specific, and Barry et al . [, ] did not draw any conclusions about the superiority of one category of equation when compared with field data.…”

Section: Introductionmentioning

confidence: 99%

“…[5] In contrast to the above expectation, most studies comparing bed load equations to measured bed load transport rates report large overestimates instead of under-estimates when equations are used with width-averaged data, especially for gravel bed rivers [Rickenmann, 2001;Barry et al, 2004;Bathurst, 2007;Recking et al, 2012]. In addition, because equations derived on the basis of field data are supposed to have a built-in allowance for the effects of spatial variability, they should considerably improve the computation of bed load transport when compared with standard 1D equations; however, many equations based on field data are also site specific, and Barry et al [2004Barry et al [ , 2007 did not draw any conclusions about the superiority of one category of equation when compared with field data.…”

Section: Introductionmentioning

confidence: 99%

An analysis of nonlinearity effects on bed load transport prediction

Recking¹

2013

JGR Earth Surface

View full text Add to dashboard Cite

[1] Because bed load equations are nonlinear and because parameters describing the flow and the bed can have large variance, different results are expected when integrating bed load over a cross section with respect to spatially variable local data (2D), or when computing bed load from cross-section-averaged data, which reduces the problem to uniform conditions (1D). Evidence of these effects is shown by comparing 1D (flume-derived) equations with 2D field measurements, and by comparing a 2D (field-derived) equation with 1D flume measurements, leading to the conclusion that different equations should be used depending on whether local or averaged data are used. However, whereas nonlinearity effects are considerable for low-transport stages, they tend to disappear for higher-flow conditions. Probability distribution functions describing the variance in flow and bed grain size distribution (GSD) are proposed, and the width-integrated bed load data (implicitly containing the natural variance in bed and flow parameters) are used to calibrate these functions. The method consists of using a Monte Carlo approach to match the measured 2D bed load transport rates with 1D computations, artificially reproducing the natural variance associated with the mean input parameters. The Wilcock and Crowe equation was used for the 1D computation because it was considered representative of 1D transport. The results suggest that nonlinearity effects are mostly sensitive to the variance in shear stress, modeled here with a gamma function, whose shape coefficient α was shown to increase linearly with the transport stage. This variance in shear stress suggests that even for very low flow conditions, shear stress can locally exceed the critical shear stress for the bed armor, generating local armor breakup. This could explain why the bed load GSD is usually very similar to subsurface GSD, even in the presence of complete armor.

show abstract

Correction to “A general power equation for predicting bed load transport rates in gravel bed rivers”

Cited by 14 publications

References 8 publications

The equilibrium alluvial river under variable flow and its channel‐forming discharge

The equilibrium alluvial river under variable flow and its channel‐forming discharge

Field measurements of the energy delivered to the channel bed by moving bed load and links to bedrock erosion

An analysis of nonlinearity effects on bed load transport prediction

Contact Info

Product

Resources

About