长洲枢纽坝下河段水沙变化及河床变形分析

分析梧州水文站1955-2010年近50年的水沙系列数据及长洲枢纽建设前后2002-2011年间坝下近坝段的地形变化.结果表明:西江径流变化相对平稳,而来沙变化经历了3个时段,自2003年起梧州水文站输沙量及含沙量急剧减小,虽然其变化的时间在长洲枢纽建设前后,但长洲枢纽的建设并非是造成坝下梧州水文站输沙量和含沙量减小的主要原因；长洲枢纽建设前后河床的剧烈变形,主要为河道采砂和航道升级整治所造成.

Variation of runoff & sediment and river bed deformation below Changzhou dam

Based on the analysis of the water and sediment variation at Wuzhou station form 1955 to 2010and the river bed deformation below Changzhou dam from 2002 to 2011, it is concluded that the runoff changewas relatively stable, but the river sediment experienced three periods, and the sediment discharge and sedimentconcentration decreased sharply after 2003. Though the change happened before and after the construction of theChangzhou dam, the Changzhou dam was not the main reason for the decreased sediment concentration. And thedramatic deformation below Changzhou dam was more possibly caused by sand mining and channel regulation.