Based on the one dimensional sediment mathematical model,sediment scour and silting in the lower Yellow River after Xiaolangdi reservoir operation are researched;therein the change law of scour and silting in the river reach of Aishan to Lijin is analyzed emphatically.

The study results of the reactive effect of the Yellow River delta changes on its estuarine course and the delta development model are introduced, the emphasis is placed on the factors affecting the Yellow River delta formation and the evolution process of scour and silting, and it is confirmed that the numerical computational method, remote sensing and GIS .

Then,the scouring and silting characteristics of debris flow and their af- fecting factors including debris flow scale and local channel.

The changes of scouring and silting of the Yellow River Delta is complicated and speedy, and it clearly lies on the changes of the coastline.

Effect of the implementation of the first-stage project of the deepwater channel regulation in the Yangtze River Estuary on the erosion and deposition in the South Passage;

Analysis on erosion and deposition evolution of the lower Yellow River;

From the law of the digging load in Fengqiwo river,it is concluded that the critical discharge of gravel bed-load in Neijiang river is 200m~3/s;the digging action in this river section has no direct effect on the relationship of flow depth and discharge;the erosion and deposition of river bed at Wotie section are mainly in.