黄河下游河道萎缩的特点及其水文学背景

通过分析黄河下游1986年以来实测资料，探讨了黄河下游1986—1999年水文系列的特点和河道萎缩的特点，指出了上世纪80年代后期以来河道萎缩使河道泄流排沙能力降低，洪水位抬高，威胁堤防安全，河道萎缩还关系到流域的开发和水资源的利用。本文还分析了河道萎缩与水沙特征的关系及河道萎缩的形成条件，并提出了判别形成河道萎缩的水沙关系。

Hydrological Background of Channel Shrinkage in the Lower Yellow River

Through analyzing the observed data from 1986 to 1999, the characteristics of flow and sediment transport and the channel shrinkage in the Lower Yellow River shaped from 1980s to 1990s were discussed in this paper. It was found that channel shrinkage in the lower Yellow River depressed the capacity of drainage and sediment transport, raised the flood level, threatened the embankment safety, and affected the exploiture of drainage area and the use of water resources. Furthermore, the relationship between channel shrinkage and the characteristics of flow and sediment transport, and conditions resulting in the channel shrinkage were analyzed. Consequently, the characteristic relationship of flow and sediment transport, which induced the channel shrinkage, was proposed.