Analysis of two kinds soil rill evolution under the secondary rainfall
Liu Junti, Sun Liying, Zhang Xuepei, Cai Qiangguo, Chen Junjie
(1.College of Soil and Water Conservation， Beijing Forestry University，100083, Beijing, China； 2.Key Laboratory of Water Cycle and Related Land
Surface Processes， Institute of Geographical Sciences and Natural Resources Research， Chinese Academy of Sciences， 100101， Beijing, China；
3.College of Resources and Environment， Huazhong Agriculture University， 430070， Wuhan, China）
Abstract：It is necessary to study different soil rill erosion for investigating rill erosion mechanism. In this paper, the secondary simulated rainfall experiments with an interval of 24hours were conducted, with different slope lengths (5，10m) and different rainfall intensities (1.5，2.0，1.0mm/min), to study the differences of runoff and sediment yield and rill space about 2 kinds soil rill erosion developments. Results showed that two kinds of soil shared similar runoff process. At the same rainfall intensity and slope length, lou soil slope surface runoff was greater than the loessial soil. In the first rainfall, the slope surface area and rill erosion intensity of lou soil was greater than the loessial soil. Once the rill erosion occured in the loessial soil slope surface, the volume variations of loessial soil was strongly than lou soil. The change process of the erosion rate could reflected lou soil rill stages of development. Rill erosion would happen with larger rainfall intensity in the loessial soil, and the duration time for stages was longer than lou soil, i.e., Loessial soil rill morphological changed slowly.
2013, Vol. 11 
