黄河内蒙古不同河型段对洪水过程的响应特征  

Flood Processes and Channel Responses in Typical Years of the Different Channel Patterns in Neimenggu Reaches of the Upper Yellow River

作　　者：王随继[1] 范小黎[1,2] 

机构地区：[1]中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室,北京100101 [2]中国科学院研究生院,北京100049

出　　处：《地理科学进展》2010年第4期501-506,共6页Progress in Geography

基　　金：国家自然科学基金项目(40771031)

摘　　要：黄河内蒙古河段的河道淤积近年来有所加重,一些人寄望于人造洪峰冲沙来降低河床。本文根据典型年份的最大洪水的流量—水位过程线变化特征,揭示黄河内蒙古不同河型段对这些洪水的响应机制,得出黄河内蒙古河段洪水的流量—水位过程线类型有线形、顺时针环线、逆时针环线3类单一关系和线形+逆时针环线、逆时针环线+线形、"8"字形+线形、嵌套状逆时针环线以及交叉线形5类复合关系。这些关系总体上可以反映洪水过程中河床是侵蚀还是沉积、何时侵蚀何时沉积、以及冲淤是否具有反复性。黄河内蒙古冲积性河段的河道对同一次洪水过程的响应沿程表现出分化现象,其中辫状河段以河床侵蚀下降为特征,弯曲河段以河床明显沉积升高为特征,而顺直河段以少量沉积或冲淤平衡为特征。不同河型段的河道对洪水的响应趋势与洪水动能的沿程减小相适应,洪峰含沙量沿程减小是该趋势的具体体现。人造洪峰冲沙难以逆转上述淤积趋势,对防治洪灾帮助有限。The sedimentation on channel bed in the Neimenggu（Inner Mongolia） reach of the upper Yellow River has been relative severe since the last two decades.Some of researchers expect that artificial flood can erode the channel bed and lower the channel bed.In this work,the discharge-water level hydrographs of the maximal floods that occurred in the typical years have been revealed,and the shapes of the hydrographs include single line,clockwise loop,anticlockwise loop,and complex line plus anticlockwise loop,anticlockwise loop plus line,＂8＂-shape plus line,nested anticlockwise loop and cross lines.These relations can reflect whether the channel bed is eroded or deposited,when eroded or deposited,and whether the erosion and deposition are iterative.The responses of the Neimenggu channel of the upper Yellow River are different from those at the downstreams.The downward erosion and the depressed channel bed have a braiding channel pattern,the evident upward aggradation has a meandering pattern,and the slight upward aggradation or the balanced erosion-deposition has a straight pattern.This trend is adaptive to the stream power decrease downstreams.The decrease of concentration of suspended sediment downstream is the evidence.Artificial flood can not change the sedimentation trend on the meandering channel bed and can not help people to inhabit in the Hetao plain to avoid the flood hazard.

关 键 词：洪水过程 河道响应 不同河型段 内蒙古河段 黄河上游 

分 类 号：TV122[水利工程—水文学及水资源]