[Water impounding characteristics of bamboo-shaped rainwater harvesting ditch in the hilly loess region].
Bamboo-shaped rainwater harvesting ditch (BRHD) is a new water harvesting and application technology being promoted in the hilly loess region of North Shannxi Province. This paper measured the soil moisture condition and water storage capacity of BRHDs filled with straw, branch or gravel through field and simulated rainfall experiments to evaluate the water holding and absorption capacity of different BRHD fillers. From May to October, the water storage of BRHDs showed a decrease trend at first and then increased in field experiment. The water storage depths within 30-200 cm profile of branch ditch (BD), gravel ditch (GD) and straw ditch (SD) were 186.76, 177.23 and 169.26 mm in May, respectively, and increased by 14.24, 20.28 and 21.23 mm in October, respectively. In contrast, the water storage depth of the level bench was reduced by 6.52 mm in October from 185.76 mm in May. The soil water restoration depth was different between BRHDs with different fillers and the level bench within 30-200 cm profile in October. The SD and BD had the deepest restoration depth (140 cm), followed by GD (110 cm), and the level bench was the minimum (80 cm). Through rainfall simulation experiment, the amount of water intercepted by BRHD was in the order of SD (99.5 L) > GD (91 L) > BD (71.5 L). The water-holding rate of straw and branch showed logarithmic function with soaking time, while the water-absorption rate followed a power function. Moreover, there was a negative logarithm correlation between water-holding rate and water-absorption rate. Straw showed a better water holding and absorption capacity than branch. Gravel had a weak water holding and absorption capacity which was almost not changed during soaking, while it displayed a negative liner correlation between water holding rate and absorption rate. The three kinds of BRHDs could be applied in the hilly loess region, and that filled with straw would exhibit the best capacity of water interception and holding.
Jun
J
Lin
You-Ke
YK
Wang
Xin-Dong
XD
Wei
Sen
S
Xiao
Xue
X
Zhang
D011891:Rain; D012987:Soil; D014867:Water; D014872:Water Movements
D012987:Soil; D014867:Water