论文部分内容阅读
不同土壤细沟侵蚀发育对比研究是探讨细沟侵蚀机制的必要内容。通过间隔为24 h的2次人工模拟降雨,在不同降雨强度(1.5,2.0,1.0 mm/min)、不同坡长(5、10 m)的试验条件下,分析坡度为20°时塿土和黄绵土2种土壤细沟侵蚀过程中产流产沙、空间变化的差异。结果表明:1)从坡面产流量来看,2种土壤在2次人工降雨过程中有相似的产流过程,坡长和降雨强度相同时,塿土坡面产流量大于黄绵土;2)从坡面形态看,第1场降雨过程中塿土坡面表面积、细沟侵蚀强度大于黄绵土坡面,但黄绵土坡面一旦发生细沟侵蚀,其体积变化幅度剧烈于塿土坡面;3)塿土在第1场降雨过程中侵蚀速率的变化过程可以反应细沟发育的各个阶段,较大降雨强度使黄绵土发生细沟侵蚀侵蚀,其细沟发育的各个阶段持续时间长于塿土,即黄绵土细沟形态变化缓慢。
The comparative study on the development of rill erosion in different soils is a necessary part of exploring the mechanism of rill erosion. Through two artificial simulated rains with an interval of 24 h, under the conditions of different rainfall intensities (1.5, 2.0, 1.0 mm / min) and different slope lengths (5 and 10 m) Differences of runoff and sediment production and spatial variation in two gully erosion processes of loessial soil. The results show that: 1) From the aspect of runoff yield, the two kinds of soils have similar runoff process during the two rainfall periods. When runoff length and rainfall intensity are the same, the runoff yield on loess slope is higher than that on loess soil. 2) In the first rainfall pattern, the surface area of loam slope and the erosion intensity of rill are larger than that of loessial soil, but once the rill erosion occurs on the loess slope, the volume variation of loessial soil is drastic on the slope of loam; 3) Soil erosion process in the first rainfall process can reflect the various stages of the development of the rill, a greater rainfall intensity rill erosion of the rill erosion of the rill, the development of the rill lasted longer than the soil, that is fine loess Groove shape changes slowly.