皇甫川高含沙水流与断面冲淤变化

Variation of River Cross Sections and High Sediment-laden Flow in Huangpuchuan River

皇甫川是黄河中游主要粗沙来源区之一。其下游河床冲淤善变,洪水前后断面变化最大可达180m^2。这种冲淤变化与高含沙水流密切相关,当含沙量大于600kg/m^3或小于100kg/m^3时,河床都发生冲刷;含沙量在100～600kg/m^3之间时,河床发生淤积。因此,受冲淤变化的影响,皇甫站断面年输沙量并不一定能反映该年的流域产沙状况。

Huangpuchuan River is one of the coarse sediment sources of the Huanghe River on its middle reaches. Variation of its cross sections is so frequent and rapid as a cross section increases or decreases in 45～275m^2 before and after a flood event. Such a variation is related to the sediment delivery characteristics of the high sediment laden flow. Scouring is taking place when sediment consentration of the flow is higher than 600kg/m^3 or less than 100 kg/m^3, and siltation occurs when sediment consentration is in a range of 100～600 kg/m^3. Therefore the regulirity of the sediment delivery and annual sediment load at the outlet section of the river cannot reflect a real regime of sediment yield on the river basion.