摘要
利用三维激光扫描仪探索多场降雨情况下同一坡面细沟侵蚀的动态过程,为解释细沟侵蚀过程提供一定的理论依据。采用室内人工模拟降雨,在坡度为15°的土槽上进行恒降雨强度的7场降雨冲刷实验,利用三维激光扫描仪对每场降雨冲刷后的坡面形态进行了监测,定量分析坡面细沟侵蚀的动态发育过程。结果表明:前2场降雨与后5场降雨产流产沙过程和细沟侵蚀发育过程有较大差异,细沟从第3场降雨开始明显发育。表现为小跌水—下切沟头—断续细沟—连续细沟—细沟沟网的发育过程。通过三维激光扫描仪精确监测7场降雨坡面各点微地形变化,发现细沟平均沟宽、平均沟深、沟长最大值、细沟平均密度在前2场降雨增长幅度较小,至第3场降雨后开始迅速增大,细沟侵蚀强度不断加强。侵蚀强度由第1场降雨的0.103 kg/m2发展至第7场降雨的8.788 kg/m2,增加了84倍。
In this paper,the 3D laser scanner were used to probe the dynamic process of rill erosion under the same slope by a multi-rainfall condition,which may provide certain theoretical basis for explaining the rill erosion process.The artificial rainfall simulation in room were adopted.Seven rainfall scouring experiments with the constant rainfall intensity were carried out on the soil bin with the slope of 15° and the 3D laser scanner was used to make the real-time monitoring of the slope pattern after each rainfall.The studies mainly focus on the dynamic development process of slope rill erosion.Results showed that there were great differences in the process of runoff,sediment and the development of rill erosion.Between the first two rainfall events and the last five ones.The rill developed obviously after the third rainfall event.Rill erosion process was presented as： small hydraulic drop-incised gully head-intermittent rill-continuous rill-rill network.By monitoring the changes of the slope points in microtopography using 3D laser scanner,it was found that the change range of landform is relatively small in the average rill width,the average rill depth,the maximum rill length,the average rill density during the first two rainfall events.These parameters began to increase rapidly after the third rainfall event.Rill erosion intensity was constantly strengthened from 0.103kg/m2 under the first rainfall to 8.788kg/m2 under the seventh rainfall with an increase of 84 times.
出处
《中国水土保持科学》
CSCD
2011年第2期32-37,46,共7页
Science of Soil and Water Conservation
基金
教育部重点项目"黄土区基于CA模型的坡面径流动态模拟与水沙效应研究"(109149)
教育部高校博士点专项基金"基于元胞自动机的坡面细沟侵蚀可视化过程模拟研究"(20100204120017)
国家自然科学基金"黄土坡面细沟发育过程的三维CA数值模拟"(41001158)
中央高校基本科研业务费专项资金资助
关键词
细沟
侵蚀
坡面形态
发育过程
三维激光扫描仪
rill
erosion
slope pattern
development process
three-dimensional laser scanner
