Characteristics of Runoff and Sediment Variations of the Yellow River Mouth

According to the observed runoff and sediment data of Lijin Hydrometric Station, the paper analyzes the characteristics of runoff and sediment variations of the Yellow River mouth since 1950. The results show that the amount of runoff and sediment flow into the estuary, water and sediment distribution within a year, yearly variations, proportion and floodcharacteristics all have been changed since 1986, i.e. the continuous dry year with less sediment is getting longer andvariation scope between years smaller; runoff and sediment characteristics in October are close to that of in non -floodseason and peak discharge is getting smaller year by year; the discharge in about 50% time of flood season and 72.8%time of the year is less than 500 m~3/s ; the proportion of small discharge mixed with sediment is increased and the proportion of big discharge mixed with sediment decreased and; the discharge reduces from 2000 m~3/s to less than 1000m~3/s and the proportion of sediment delivery of 3000 m~3/s discharge is reduced by 43.35%