近60 年黄河入海水沙多尺度变化及其对河口的影响

基于1950-2008 年利津站月均径流量和输沙量的时间序列资料，采用小波分析的方法研究了黄河入海水沙多尺度变化，并结合不同年份的黄河口岸线和口门地形资料分析了水沙变化对河口演变的影响。结果表明：黄河入海水沙具有3 个不同时间尺度的显著周期变化，其与厄尔尼诺事件有关，不同尺度下的入海水沙丰枯变化不同；受流域降水和人类活动的影响，入海水沙长期呈减少趋势，并具有阶段变化的特征；入海水沙变化深刻影响着河口演变，不同时期行水河口的岸线延伸速率与河口来沙量有关，亿t 泥沙岸线延伸量与来沙系数显著相关，自1976 年清水沟流路入海以来，河口水下三角洲表现为淤积，淤积程度与入海水沙量密切相关。

Multi-scale Variability of Flow Discharge and Sediment Load of Yellow River to Sea and Its Impacts on the Estuary during the Past 60 Years

Based on the hydrological data of Lijin station from 1950 to 2008, the temporal change of flow discharge and sediment load of Yellow River to sea is analyzed by the wavelet analyses. What's more, the impacts of their changes on the estuary are studied based on the measured coastline and bathometric data. The results show that there are three significant periodic variations for flow discharge and sediment load, which may be related with the periodic variations of ENSO, additionally, the variations of flow discharge and sediment load are varying in different time scales. The long-term variation of flow discharge and sediment load are stepwise decreasing because of the combined influences of human activities and precipitation. The evolution of the Yellow River Estuary is in relation with the flow discharge and sediment load, the stretch speed of its coastline in different periods is significantly correlated with the incoming flow discharge and sediment load, and the subaqueous topography near the estuary has exhibited siltation generally since 1976. Furthermore, the siltation extent is closely related with the flow discharge and sediment load into sea.