摘要
应用基于蓄量动力学方程推导出的水文相似因子——山坡Péclet数(简称Pe),研究了Pe在不同地貌条件山坡间的变化特征、影响因素及其表达的水文响应特性。结果显示,在和睦桥流域,山坡Pe值一般为200～2 000。分析发现,Pe与坡长厚度比(L/D)呈显著的线性相关关系(R2=0.94),关系线斜率为0.95,表明Pe在数值上决定于L/D,即山坡水文特征受山坡尺寸的影响较大。为了说明山坡形状的影响,选取了山坡水平、剖面曲率,分析了其与Pe值的相互关系。研究发现,发散型凸坡Pe值一般较大,有利于土壤水流的消退,对流运动是其主要的运动形式,而收敛型凹坡Pe值一般较小,不利于土壤水流的消退,水分运动中的扩散作用更强。这与理论分析结果一致,表明Pe数在分析山坡结构特征的水文效应方面有一定意义。
Using the software DigitalHydro V1.0,the hillsploe Péclet（Pe） number is derived for the Hemuqiao catchment in the source area of the Tai Lake basin together with the hillslope unit and the profile/plan curvature.The 1∶10 000 elevation contour lines and 90 samples of soil depths are used for the derivation of these hillslope parameters.The hillsploe Pe number is a dimensionless similarity factor.Its physical meaning is analyzed through the construction of correlation functions involving four selected geomorphic parameters e.g.the length,the soil depth,the convergence ratio and the slope of a hillslope.The correlation between the ratio of hillslope length and soil depth（L/D） and the hillsploe Pe number is also studied.The result shows that Pe value of different hillslope types in the catchment generally varies from 200 to 2 000,and there is a strong linear relationship between L/D and Pe with the high value of R2=0.94.The slope of the linear trend line is 0.95,indicating that the ratio of L/D has a strong positive impact on Pe.The analysis of hillslope contour and profile curvature reveals that the advective component will overwhelm the diffusive component when the shape of hillslope changes from convergent to divergent plan shape and from concave to convex profile shape.
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2012年第1期1-6,共6页
Advances in Water Science
基金
国家自然科学基金资助项目(40801013)
中国博士后科学基金特别资助项目(201003572)~~
关键词
无因次
相似因子
山坡结构
水文响应
dimensionless factor
similarity analysis
hillslope structure
hydrological response
作者简介
刘金涛（1977-），男，河北唐山人，副研究员，博士后，主要从事山坡水文学及流域水文模拟方面的研究。E—mail：jtliu@hhu．edu．cn
