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.