兰州附近黄土坡地的降雨模拟试验  

RAINFALL SIMULATION TESTS ON LOESS SLOPE OF GOLAN SHAN AROUND LANZHOU

作　　者：王靖泰[1] 陈瑾[1] M.塔捷亚娜 A.别娅 E.德比希尔 

机构地区：[1]甘肃省科学院地质自然灾害防治研究所 [2]法国科学研究中心 [3]英国莱斯特大学黄土研究中心

出　　处：《中国地质灾害与防治学报》1993年第3期44-52,共9页The Chinese Journal of Geological Hazard and Control

摘　　要：在较陡的黄土坡地上进行了一系列降雨模拟试验,以便评价雨水的入渗及水土流失情况。试验结果表明,在雨强和地面坡度相同的情况下,表面径流和泥沙含量取决于地面类型。一般耕作地明显地大于牧地和荒坡。在同类地面上,径流系数和输沙量随雨强和坡度的增加而增加,然而雨壳和干裂对表面径流有抑制作用。在黄土坡地上暴雨产生的表面径流对坡面的冲刷和由此造成的水土流失是严重的。A series of rainfall simulation experiments was undertaken on steep loess slopes, in order to assess the importance of overland flow and soil erosion in different land use situations.The results show that for slopes with similar gradient and similar rainfall intensities, runoff is clearly greater on the recently ploughed plots than on the plots under pasture.On cultivated fields, the runoff coefficient and transporting silt increases with rainfall intensity, reaching 95% and 106. 6 g/min respectively at 87 mm/h. Runoff coefficients increase with repeated simulations on the same plot, at similar or even lower intensities. This is a result of modification of the soil surface by splash and sheetflow which leads to destruction of clods and aggregates, sealing of pores and the formation of a surface crust of low permeability. These long - lasting changes occur more rapidly and efficiently as the rainfall rate increases. On sealed soil after natural heavy rain, the overland flow was found to be reduced by infiltration into desiccation fissures. The effect of cultivation of steep slopes on the landslide risk is clearly shown.

关 键 词：降雨模拟 径流 黄土坡 径流含沙量 糙度 

分 类 号：P694[天文地球—地质学]