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It has been the conventional assumption that wash load is supply limited and is only indirectly related to the hydraulics of a river. Hydraulic engineers also assumed that bed-material load concentration is independent of wash load concentration. This paper provides a detailed analysis of the Yellow River sediment transport data to determine whether the above assumptions are true and whether wash load concentration can be computed from the original unit stream power formula and the modified unit stream power formula for sediment-laden flows. A systematic and thorough analysis of 1,160 sets of data collected from 9 gauging stations along the Middle and Lower Yellow River confirmed that the method suggested by the conjunctive use of the two formulas can be used to compute wash load, bed-material load, and total load in the Yellow River with accuracy. [ABSTRACT FROM AUTHOR]

The Sanmenxia Dam built in 1960 in the middle reach of the Yellow River has experienced severe sedimentation problems, not only in the reservoir area itself but also extending hundreds of kilometers in the backwater region. Morphological responses in the middle Yellow River and its tributary, the Wei River, upstream of the dam have generally lagged behind the causal changes in upstream and downstream controls. Based on the geometrical characteristics of a wedge-shaped sedimentation body, a method was derived for calculating equilibrium values of the accumulated sedimentation volume in the channel reaches. Combining the method for calculating with rate law models for channel morphological adjustment, a method for calculating the accumulated deposition volumes was derived. The results showed that the proposed method can accurately simulate sedimentation processes in the study reaches during 1960 and 2011, in the response to the integrated impacts of base level fluctuations and changes in incoming water and sediment discharges. The characteristics of the potential adjusted (equilibrium) morphology was analyzed and it is shown that while the nature of the adjusted (or equilibrium state) of the fluvial system varies dynamically with external conditions, it generally acts as the target for the observed channel adjustments, although the actual values of variables defining the fluvial system seldom adjust to their corresponding equilibrium values due to the effects of multiple disruptions, continuously varying water and sediment inputs, and delayed responses in the fluvial system. [ABSTRACT FROM AUTHOR]