摘要
以云南元谋干热河谷典型坡面上改造后的微地形为研究对象,对集中降雨条件下的土壤水分进行动态监测,运用土壤水分动力学原理和水量平衡原理,分析计算改造微地形的土壤水分特征曲线、土壤水分通量、导水率和扩散率,结果表明：微地形改造后,强化了降雨的入渗,水平沟整地和水平台整地分别能将89%和83%的降雨转化为土壤水分,而自然坡面只有22%的天然降雨转化为土壤水分,集中降雨后,土壤水分以垂直入渗为主,土壤水分以零通量面为界,在零通量面以上水分向上运动,零通量面以下向下运动,改造后微地形土壤水分运移动速度明显增大,最大运移速度大约为15~17 cm/d,但随着坡度增加,土壤水分的侧向损失有所增加,在集中降雨条件下,水平台、水平沟整地后能使拦截的降雨在0-200 cm土层范围进行分配,且缓坡上的水平台能使100 cm以下的土壤水分得到明显改善,而自然坡面入渗的水分主要在0-100 cm范围分配,且改善土壤水分效果不好,100 cm以下土层,降雨后土壤水分仍维持在较低水平。
Taking reconstructed micro-slope on typical slope in Yuanmou dry-hot river valley as research object,by monitoring soil water dynamics,this paper analyzes and calculates soil water characteristic curve,soil water flux,conductivity and diffusivity of reconstructed micro-slope with soil water dynamics principle and water equilibrium principle.The results show that reconstructed micro-slope enhances the permeating of rain,contour terrace and contour trench could respectively converse 89% and 83% rainfall into soil water,but natural slope only could converse 22% rainfall into soil water.Soil water mainly permeates at perpendicular direction,and moves upward on zero flux noodles,gets down under zero flux noodles after concentration rain.Reconstructing micro-slope makes the speed of water movement increase,and the biggest speed increased 15~17 cm/d.With the depth increases of soil profile,the lost of soil water on the side increases correspondently.The intercepted rain of contour terrace and contour trench can be assigned in 0-200 cm soil layer,contour terrace on gentle slop may make water under 0-100 cm soil layer increase obviously,and the permeating water of natural slop mainly is assigned in 0-100 cm soil layer,water under 0-100 cm soil layer always keeps very low.
出处
《水土保持研究》
CSCD
北大核心
2008年第4期19-23,共5页
Research of Soil and Water Conservation
基金
国家自然科学基金项目(30660037)
云南省科技计划项目(2006SG20)
云南省自然科学基金项目(2006D0041M)
云南省教育厅基金项目04Y424B资助
关键词
元谋干热河谷
微地形改造
土壤水分
yuanmou dry-hot river valley,reconstructed micro-slope,soil moisture
