泥沙研究Issue(1)：68-73,6.
典型沙洲形态与河道的关系
Relationship between morphology of typical sand bars and river channels
摘要
Abstract
Sand bars are the result of long-term sediment deposition in alluvial rivers. A river channel not only provides a development space for a sand bar but also restricts its free development. Three types of sand bars, including ellipse, bamboo leaf and sickle sand bars are classified from satellite images, in which 653 sand bars are in Yangtze, Hanjiang, Xijiang, Xiangjiang, Amur, Mississippi and Irtysh Rivers. The relationship between the three typical sand bars and river channels is analyzed. The ellipse sand bars in seven alluvial rivers are the most widely distributed and their quantity is larger than bamboo leaf sand bar and sickle sand bars. The area and perimeter of bamboo leaf sand bars are generally the largest, the sickle sand bars are in the middle and the ellipse sand bars are the smallest. Relationship between sand bars area and perimeter and relationship between sand bar area and channel width follow the law of power function. The relationship between the sand bar average width and the channel width has good linear correlation; the correlation coefficients diminish from the sickle, then the bamboo leaf to the ellipse. Simultaneously, the relationship between the sand bar perimeter and the channel width has linear correlation; the correlation coefficients diminish from the sickle, then bamboo leaf, to the ellipse. The river channel is divided into a primary channel and a secondary channel by a sand bar. The branching ratio of river channel for the three typical sand bars is located in the range from 0. 09 to 0. 97.关键词
冲积河道/沙洲/沙洲形态/河宽/分汊比Key words
alluvial river channel/ sand bar/ sand bar morphology/ river width/ branching ratio分类
建筑与水利引用本文复制引用
李志威,王兆印,张康..典型沙洲形态与河道的关系[J].泥沙研究,2012,(1):68-73,6.基金项目
清华大学自主科研计划课题(2009THZ02234)“三江源河流生态动力学综合研究” （2009THZ02234）
