流量变化对黄河下游河道演变影响

Influence of discharge variation on fluvial process of the Lower Yellow River

作者通过对1958、1964、1973、1985及1997各年黄河下游花园口、高村、艾山、利津水文站逐日平均水文资料的流量级分析,得到花园口、高村、艾山、利津水文站日均造床流量1958年为3400～4400m3 s;1964年5300～5600m3 s;1973年为2700～3300m3 s;1985年有两个峰值,分别为1900～2000m3 s和3800～4500m3 s;1997年仍有两个峰值,花园口和高村水文站为680～740m3 s和1900～2800m3 s,艾山和利津水文站为200～250m3 s和510～820m3 s。将上述结论与对实测资料的分析相结合,得到造床流量明显下降及较大日均流量(>2000m3 s)出现频率大大减少甚至不再出现是黄河下游小流量输沙、河道淤积、"小水大灾"的根本原因。

The authors made a discharge magnitudefrequency analysis based on the daily discharge observations at 4 stations on the Lower Yellow River in the years of 1958,1964,1973,1985 and 1997. The channel forming discharges at these stations were derived The analysis showed that the channel forming discharges reduced obviously than before and the accruing frequency of daily discharges larger than 2000 m3/s decreased or even vanished. The variation of the channel forming discharges was the cause for 'transporting sediment with small discharges', bed aggregation and 'a normal flood resulting in a tremendous disaster'.