摘要
基于室内人工模拟降雨试验,采用三维激光扫描仪对坡面进行监测,研究了黄土坡面不同坡度(10°,15°,20°,25°)和雨强(90,120mm/h)下细沟发育过程、形态特征及细沟与细沟间侵蚀比率变化规律。结果表明:(1)随着坡度、降雨强度增大,坡面产流时间、细沟出现时间有减小趋势,断面流速有增大趋势;(2)黄绵土坡面细沟形态变化受降雨强度影响较小,受坡度影响较大。在10°,15°坡度条件下,受溯源侵蚀及沟道下切作用较强,形成的细沟长、窄,深;在20°,25°条件下,受沟壁坍塌作用影响较大,形成的细沟短、宽、浅;(3)采用多元回归方法对细沟与细沟间侵蚀比率与坡度、雨强、径流的关系进行拟合,拟合函数为幂函数方程,细沟与细沟间侵蚀比率随着坡度、降雨强度增大而增大。
Indoor rainfall simulation experiments were conducted in this study under different slope gradients（10°,15°,20°,25°）and different rainfall intensities（90,120 mm/h）.The rill development process,morphological characteristics and variations of rill and inter rill erosion rate were analyzed with the help of the 3Dlaser scanner.Results showed that runoff generation time and rill occurrence time decreased with rainfall intensity and slope degree.The runoff velocity increased with the enlargement of rainfall intensity and slope degree.Compared with the rainfall intensity,slope degree showed a larger impact on rill morphology features.When slope degrees were 10°or 15°,slopes influenced mainly by headward erosions and vertical erosions,and rills formulated by them had long,narrow and deep features.When slope degrees were 20°or 25°,slopes influenced mainly by side wall collapse then rills formulated had short,wide and shallow features.Multiple regression method was used to fit relationships between erosion rate and slope gradient,rainfall intensity and runoff and we got a power function equation.The fitting function was a power function equation,and the inner rill erosion rate increased with the slope degree and rainfall intensity.
出处
《水土保持学报》
CSCD
北大核心
2015年第1期12-16,共5页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目"黄土坡面细沟侵蚀和细沟间侵蚀贡献率变化规律研究"(41171228)
国家自然科学基金项目"片沙覆盖黄土区沙土二元结构坡面土壤侵蚀机理研究"(41371283)
水利部公益性行业科研专项"小流域淤地坝坝系防洪风险评价技术"(201201084)
关键词
细沟发育
模拟降雨
坡度
降雨强度
侵蚀比率
三维激光扫描仪
rill development
simulated rainfall
slope gradient
rainfall intensity
erosion rate
3Dlaser scanner
