scholarly journals Streamflow and suspended-sediment discharge from two small watersheds in southwestern Wyoming and northeastern Utah, 1984

1985 ◽  
Author(s):  
L.W. Lenfest ◽  
B.H. Ringen
2004 ◽  
Vol 35 (2) ◽  
pp. 165-174 ◽  
Author(s):  
Hafzullah Aksoy ◽  
Tanju Akar ◽  
N. Erdem Ünal

Wavelets, functions with zero mean and finite variance, have recently been found to be appropriate tools in investigating geophysical, hydrological, meteorological, and environmental processes. In this study, a wavelet-based modeling technique is presented for suspended sediment discharge time series. The model generates synthetic series statistically similar to the observed data. In the model in which the Haar wavelet is used, the available data are decomposed into detail functions. By choosing randomly from among the detail functions, synthetic suspended sediment discharge series are composed. Results are compared with those obtained from a moving-average process fitted to the data set.


Estuaries ◽  
1978 ◽  
Vol 1 (2) ◽  
pp. 106 ◽  
Author(s):  
M. Grant Gross ◽  
M. Karweit ◽  
William B. Cronin ◽  
J. R. Schubel

2020 ◽  
Vol 13 (21) ◽  
Author(s):  
Caiwen Shu ◽  
Guangming Tan ◽  
Yiwei Lv ◽  
Quanxi Xu

AbstractUsing experimental data of near-bed suspended sediment concentrations at five typical hydrometric stations of the Three Gorges Reservoir at the early reserving stage, the differences were investigated between the common method and improved method during flood seasons and non-flood seasons. The impact of taking measurements below 0.2 times the water depth on the results was discussed. The results show that the average discharges and velocities at each station calculated by the common method were slightly larger than those calculated by the improved method. Regarding the suspended sediment concentration at each station, the errors in the reservoir and downstream channels in dynamic equilibrium state were small, and the largest errors occurred where the river bed was strongly scoured in the downstream reach below the large dam. There was no significant relationship between water discharge and flow velocity, and the missed measurement phenomenon also occurred. The sediment discharge error was affected by the suspended sediment concentration, implying that errors usually occurred in channels with serious erosion during flood seasons. The correction coefficients (R2) of sediment discharge at each station were given during the experiment, which showed that the sediment discharges at the hydrometric stations where a large amount of sediment transport occurred near the river bottom, needed to be modified. Furthermore, the test methods proposed in this study were applied to calculate the sediment discharges of three rivers, and the results indicate that this method can narrow the gap between bathymetric comparisons and sediment load measurements.


2020 ◽  
Author(s):  
J. Jotautas Baronas ◽  
Edward T. Tipper ◽  
Michael J. Bickle ◽  
Robert G. Hilton ◽  
Emily I. Stevenson ◽  
...  

<p>A large portion of freshwater and sediment is exported to the ocean by just several of the world's major rivers. Many of these mega-rivers are under significant anthropogenic pressures, such as damming and sand mining, which are having a significant impact on water and sediment delivery to deltaic ecosystems. However, accurately measuring the total sediment flux and its mean physicochemical composition is difficult in large rivers due to hydrodynamic sorting of sediments. To account for this, we developed an updated semi-empirical Rouse modeling framework, which synoptically predicts sediment concentration, grain size distribution, and mean chemical composition (organic carbon wt%, Al/Si ratio) with depth and across the river channel.</p><p>We applied this model to derive new sediment flux estimates for the Irrawaddy and the Salween, the last two free-flowing mega-rivers in Southeast Asia, using a newly collected set of suspended sediment depth samples, coupled to ADCP-measured flow velocity data. Constructing sediment-discharge rating curves, we calculated an annual sediment flux of 326 (68% confidence interval of 256-417) Mt/yr for the Irrawaddy and 159 (109-237) Mt/yr for the Salween, together accounting for 2-3% of total global riverine sediment discharge. The mean flux-weighted sediment exported by the Irrawaddy is significantly coarser (D<sub>84</sub> = 193 ± 13 µm) and OC-poorer (0.29 ± 0.08 wt%) compared to the Salween (112 ± 27 µm and 0.59 ± 0.16 wt%, respectively). Both rivers export similar amounts of particulate organic carbon, with a total of 1.9 (1.0-3.3) Mt C/yr, contributing ~1% of the total riverine POC export to the ocean. These results underline the global significance of the Irrawaddy and Salween rivers and warrant continued monitoring of their sediment fluxes, given the increasing anthropogenic pressures on these river basins.</p>


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