两种乔木枯落物糙率系数的室内分析  

An Analysis on the Effect of Two KindS of Arbored Litter to the Roughnes Coefficient Experimented in the Laboratory

作　　者：张洪江[1] 北原曜[2] 

机构地区：[1]北京林业大学水土保持学院 [2]日本国际协力事业团日本森林综合研究所

出　　处：《北京林业大学学报》1994年第S4期72-78,共7页Journal of Beijing Forestry University

摘　　要：对2种乔木树种枯落物的曼宁糙率系数,进行了室内实验.在特定条件下,糙率系数(n)值与被试枯落物量呈现指数相关关系.实验结果显示,刺槐枯落物比油松枯落物对糙率系数的影响程度要大,当枯落物量为0.200g/cm^2(相当于20t/hm^2)时,刺槐和油松枯落物的糙率系数值分别是0.1 784和0.1297.研究结果还显示出枯落物量的增加对糙率系数的增大有一定限度,当单宽流量q为94ml/m·s时,枯落物量的上限值为0.250～0.300g/cm^2(相当于25～30t/hm^2).In the laboratory,the effect of two kinds of arbored litter to the value of roughness coefficient in the Manning Formula were studied.The formulas of power relating between the value of roughness coefficient and the amount of the litter have been gotten.The result shows that the more litter,the higher value is,and at the same coditions the effect of Robinia pseudoacacia Linn.litter to the roughness coefficient is bigger than that of Pinus tab- ulaeformis Carr.litter.The roughness coefficient value(n)of Robinia pseudoacacia Linn.litter.is 0.1784 and the roughness coefficient value(n)of Pinus tabulaeformis Carr.litter is 0.1297.while the amount of the litter is 0.200g/cm^2.The results also show that a limitation of increasing the roughness coefficient value exists by increasing the litter amount.The top limitation of the litter amount is about 0.250g/cm^2～0.300g/cm^2(equal 25t/hm^2～30t/hm^2)while the unit width flow(a)is about 94ml/m·s.

关 键 词：枯落物 糙率系数 水力学实验 

分 类 号：S714[农业科学—林学]