半干旱黄土丘陵区坡地集流水平沟的设计与应用

Engineering Design and Application of Leveled Ditch for Surface Runoff Harvesting on Slope Land in Semiarid Loess Hilly Areas

为解决现行集流水平沟设计方法缺乏合理性和系统性的问题,从理论分析入手,研究了这类工程的内涵及断面参数,并对集流水平沟工程的集流蓄水效果进行了研究。结果表明,2002—2008年的6a中,在整个生长季3—9月内,集流水平沟的土壤贮水量均明显高于隔坡的土壤贮水量;在试验雨强和降雨量条件下,25°坡面水平沟在3个雨强条件下拦截坡面径流量分别为4.41,64.23,104.13mm;35°坡面水平沟在2个雨强条件下拦截坡面径流量分别为5.25和72.39mm,而且单位时间内水平沟拦截坡面径流的潜力也随雨强的增大而增大。研究结果表明高强度降雨对坡地改造后水平沟的水分补给具有重要意义。

In order to solve the problem of absent rationality and system in leveled ditch design for runoff har- vesting, the objectives, cross-section parameters, and havesting potential were studied for leveled ditch de- sign in both theory and experiments. The results show that in the growing seasons （March to September） of the 6 years from 2002 to 2008, water stored in the soil on the slope with leveled ditches was significantly higher than that on the natural slope, in the test rainfall intensity and rainfall, the intercepted runoff were 4.41, 64.23, and 104.13 mm on a 25~ slope with leveled ditches, and were 5.25, 72.39 mm on a 35~ slope with leveled ditches, respectively. The intercepting capacity per unit time increased with the increase of rain- fall intensity, reflecting the importance of high-intensity rainfall to surface runoff harvesting after slope transformation with leveled ditches.