在植被发育程度较高的云南昭通头寨试验区和呈贡段家营试验区,使用亚甲基蓝和罗丹明B溶液多次进行染色示踪渗透试验,发现根-土间隙的导流现象十分明显,其导流作用很可能已经超过了传统的三类土体大孔隙。对不同尺寸根-土间隙流道内水分入渗速度模型进行推导与理论计算,并将其与实测实值进行比较分析,最后讨论了头寨试验区和呈贡段家营试验区斜坡土体中根-土间隙在降雨入渗过程中导流量所占比例。结果表明:昭通头寨和呈贡段家营试验区斜坡土体中根-土间隙的尺寸主要集中在0.5~1.0 mm,多数间隙尺寸为0.5 mm左右,根-土间隙流道内水分下渗速度主要分布在区间0.027~0.203 mm/s和0.014~0.102 mm/s,两试验区土体中根-土间隙的导流量分别占总入渗量的72%~82%和54%~70%,相同面积上,头寨试验区土体中根-土间隙的导流量是呈贡段家营试验1.67倍,根-土间隙对降雨入渗的贡献是显著的。
The experimental area with high vegetation at the Touzhai,Zhaotong and Duanjiaying,Chenggong,Yunnan Province,respectively using methylene blue and rhodamine B solution dyed tracer penetrant test hadbeen usecl many times and It found that the guiding flow phenomenon was very obvious. The diversion function is likely more important than the traditional three kinds of soil macropore. A water infiltration velocity model was derived and the theoretical calculation was performed at different sizes of the soil-root interstices,and compared with the measured values,finally,the guide flow proportion of soil-root interstice is discussed of the rainfall process in the Touzhai and Duanjiaying test area. Results show that the size of soil-root interstice are mainly concentrated in the size 0. 5 ~ 1. 0mm,most of the size is about 0. 5 mm,the water infiltration speed in soil-root interstice are in the range of 0. 027 ~0. 203 mm / s and 0. 014 ~ 0. 102 mm / s in the Touzhai and Duanjiaying test area. The infiltration volume accounted for 72% ~ 82% and 54% ~ 70% of total amount of infiltration in two test areas,on the same area,the seepage flow of the Touzhai test area is 1. 67 times more than the Duanjiaying test area,the contribution of soil-root interstice to the rainfall infiltration is notable.