黄河口清水沟流路演变分析

Fluvial process for the Qingshuigou river course of the Yellow River estuary

自１９４７年黄河归故，黄河河口流路先后经历了１９５３年小口子裁弯、１９６４年罗家屋子人工破堤和１９７６年人工截流改道清水沟流路３次较大的改道。本文根据实测资料，分析了清水沟流路的演变特点及与其它流路的不同点，分析认为：清水沟流路时期的年平均来水来沙量较神仙沟、钓口河时期明显减少，且更加集中于汛期，就来水来沙总量看，上述三条流路已经相当，但清水沟流路行水历时最长。清水沟流路经历了改道初期的游荡摆动后，逐渐归股，至１９８０年汛后，已形成比较单一顺直的河型，一直维持至今。清水沟流路的冲淤变化经历了淤积———冲刷———淤积的过程，同流量水位的变化与之对应。目前，清水沟流路正处在回淤时期。

Since the Yellow River returned to its original course in 1947,three greater changes of the river course of the Yellow River estuary,the meander cut off at Xiaokouzi in 1953,the artificial dyke break at Luojiawuzi in 1964 and the artificial channel migration to the Qingshuigou course in 1976 have been recorded. This paper, based on the measured data, analyzes the characteristics of the fluvial process of the Qingshuigou river course and the differences between the course and the others. The analyses indicate that the average annual incoming runoff and sediment load in the Qingshuigou course period have obviously decreased and mainly concentrated in flood seasons as compared with the other periods in which the river flowed in the Shenxiangou and the Diaokouhe river courses. As far as the total amounts are concerned, the three river courses mentioned above are well matched, but the time when the incoming runoff and sediment flowed in the Qingshuigou course is the longest. After wandering and shifting in the early stage of its avulsion,the Qingshuigou gradually merged branches into one,and by the year of 1980 a single and straight channel was already formed and maintained up to now. The Qingshuigou river course suffered the processes of deposition erosion redeposition and the corresponding changes of water level at the same discharge,and now it is in the process of re deposition.