Influences on Erosion and Sedimentation of Lower Weihe River Estuaries and Reaches by Rechanneling of North Luohe River Directly into Yellow River

摘要

The rechanneling of North Luohe River directly into Yellow River involves the elevation of Tongguan,flood-prevention works at the lower Weihe River and bed evolution problems of the confluence area of the three rivers and generates huge social and environmental influences.Confluence estuary of the rechanneled course into Yellow River relies on the Niumaowan project,and the included angle between its inflow angle and the main stream channel is larger and the Yellow River is changeable continuously,so the rechanneled North Luohe River will definitely generate certain influences over the pattern courses in the North Main Stream and the North Luohe River estuary.According to the test,when North Luohe River is hit by highly sediment concentrated flood,the reaches around the confluence estuary of the North Luohe River is easily to be silted and the Niumaowan project at lower reaches of the confluence estuary may easily off river,finally result in weakening of control over the reaches.But the rechanneling of North Luohe River has not changed the river patterns at the confluence area of the North Main Stream station fundamentally.