川东丘陵区柏木林水土保持措施径流调控效果对比

川东地区是我国重要的生态功能区。针对该区域由于水土流失导致的柏木林生态服务功能日益下降的现状,通过天然降雨下坡面径流小区降雨径流原位观测试验,对比分析了3种坡面水土保持措施径流调控的效果。研究结果表明：当场降雨在一定阈值内：总雨量9.6-51.0mm,平均雨强3.4-31.9mm.h^-1,随着雨量增大、雨强增强,措施径流小区径流调控能力逐渐增强,对照径流小区的平均径流系数达到了措施径流小区的 1.8倍,措施径流小区平均入渗率达到了对照径流小区平均入渗率的3.6倍。水平阶、垒穴/培土和综合措施最大可消减径流峰值的54%、46%和55%,最大可减少坡面径流总量的59%、39%和38%。中雨时,垒穴/培土措施和综合措施消减径流峰值、减少坡面径流总量的效果优于水平阶；大雨、暴雨时,水平阶优于垒穴/培土措施和综合措施,尤其是短历时、强降雨。综合消减径流峰值、减少径流总量的作用来看,在川东雨季多短历时、暴雨的气候特点下,水平阶能够发挥最优的水土保持效果。

Study on the Runoff Regulation Effect of Soil and Water Conservation Measures in cupressus funebris Plantation in East Sichuan

East Sichuan is an important ecological functional area in China. In view of the low ecological service function caused by soil and water loss of low efficiency cupressus funebris plantation in this area, the runoff regulation effects of three soil and water conservation measures: level terrace, tree-cave build /soil cover and comprehensive measures (tree-cave build /soil cover plus micro terrain modification) were compared and analyzed by means of in-situ observation experiment of rainfall runoff in slope runoff plot under natural rainfall. The results showed that: When the total rainfall was 9.6-51.0 mm, the average rainfall intensity was 3.4-31.9 mm.h^-1, with the gradual increase of rainfall and rainfall intensity, the effects of the soil and water conservation measures were gradually increasing in runoff regulation. The average runoff coefficient of non-measure runoff plot is 1.8 times of that of measure runoff plot, and average infiltration rate of measure runoff plot is 3.6 times of that of non-measure runoff plot. The maximum proportion of runoff peak value could be reduced by 54%, 46% and 55%, and the total amount of runoff could be reduced by 59%, 39% and 38% by level terrace, tree-cave build /soil cover and comprehensive measures, respectively. In the case of moderate rain, tree-cave build /soil cover measure and comprehensive measures were better than level terrace measure in reducing runoff peak value and the total amount of runoff on the slope, however in the case of heavy rain and rainstorm, the level terrace measure had the best effects than two other measures in reducing the peak runoff and the total amount of runoff, especially in short-duration and high-intensity rainfall. From the perspective of reducing the runoff peak value and the total amount of runoff, the level terrace measures can exert the best runoff regulation effect under the climatic characteristics of short-duration and high-intensity rainfall of the rainy season in eastern Sichuan.