According to the measured data of sediment of many important hydrological stations in the middle and lower stream of the Yellow River for more than 50 years,the multi-method of hydrology,mechanics of sediment transport,fluvial process and statistics are applied to study the patterns of variations in the sediment flux in recent 50 years.

The paper summarizes the present status of study on delta sediment flux both at home and abroad,involving hydro-sediment statistical model,deposition dynamics and mathematical model.

The errors of the crosssectional sediment flux estimation mainly origin from survey site layout and flux calculation method.

Similar conditions of deposition and suspension for distorted model are incompatible and from theoretical analysis,it is demonstrated that both of the above two similar conditions are not tenable,and a similar condition of vertical sediment flux ratio is presented as a substitute.

Thus, effort is made to elucidate the relation between the sediment flux into the sea and the drainage basin factors including climate and human activities.

Turbulent bursting-based sediment pick-up flux from loose bed;