人工降雨模拟试验的相似性和应用性探究

An Exploration on the Similarity and Applicability of Simulated Rainfall Experiments

为了探究人工降雨模拟试验结果的相似性,通过文献数据和观测数据,分析了人工降雨模拟试验与天然降雨小区观测在径流、泥沙方面的差异及其原因,从数值和规律2方面深入讨论了室内模拟降雨试验结果的相似性问题。结果表明:(1)模拟降雨试验弱化了降雨因子对坡面径流和泥沙的影响,且雨强/雨量或降雨侵蚀力越小,模拟试验的相似性越差。(2)模拟降雨试验中产流和产沙随坡度的变化规律明显不同于天然降雨观测情况。(3)在坡面条件和降雨作用相同的情况下,在黄绵土坡面上利用静止喷嘴式降雨机进行人工降雨试验观测得到的土壤侵蚀量不到天然降雨小区的50%。因此,模拟降雨试验结果在数量和规律上与天然降雨观测结果存在一定差异性,二者的相似性问题需要进一步研究。

To explore the similarity of the simulated rainfall experiments,based on literature data and observation data,this paper analyzed the differences of runoff and soil yield between indoor simulated rainfall experiments and natural rainfall observations in situ.The following results were obtained：（1）Simulated rainfall experiments could weaken the effect of rainfall on runoff and soil yield;the smaller intensity,precipitation amount or erosivity was,the lower similarity was to get.（2）The changing patterns of runoff and soil yield with the changing slope degree in the simulated rainfall experiments deviated from the patterns under natural rainfall.（3）While the conditions of the slope and the rainfall were identical,the soil yield from loessal sloping land under the stationary nozzle-type rainulator was far less than 50 percent of observations from natural rainfall.Consequently,there are some differences between simulated rainfall experiments and natural rainfall observations,and similarity merits future research.