室内小流域降雨产流过程试验  

Laboratory experiments of runoff processes in small watershed under simulated rainfall

作　　者：屈丽琴[1] 雷廷武[1,2] 赵军[2] 余新晓[3] 高佩玲[4] 闫丽娟[1] 

机构地区：[1]中国农业大学水利与土木工程学院,北京100083 [2]中科院、水利部水土保持研究所土壤侵蚀与旱地农业国家重点实验室,杨凌712100 [3]北京林业大学水土保持学院水土保持与荒漠化防治教育部重点实验室,北京100083 [4]山东理工大学资源与环境工程学院,淄博255049

出　　处：《农业工程学报》2008年第12期25-30,共6页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目(40635027)

摘　　要：该研究采用新型的小水流流量自动观测系统,在室内小流域模型上进行了不变雨强和变雨强模拟降雨试验,实时观测了模型流域各沟道的产流过程。试验进行了不同降雨强度(25、50、75、120mm/h)和不同降雨历时(5、10、15min)组合的12次降雨试验,同时进行了30-70mm/h和70-30-70mm/h的变雨强降雨试验。在不变雨强的条件下,仪器与人工测量所得稳定流量的最大平均相对误差仅为2.02%。测量得到的流量过程线呈现出起流、稳定和退水3个明显的阶段。其中,起流和退水过程涨落的剧烈程度、稳定阶段的流量大小随雨强增大而增大,稳定阶段的持续时间与降雨历时成正比。空间上,主沟出口的产流过程明显滞后于支沟出口的产流过程,且其两者之间具有一致的流量过程。在变雨强的情况下,流量过程线没有稳定的阶段,流量随雨强变化而变化。该研究对于深入理解流域产流过程具有重要意义,可为相关的模型研究提供可靠的试验支持。A new automatic measurement system of flow was applied.Simulated rainfall experiments were conducted under constant and variable rainfall intensity in small watershed in the laboratory.Runoff processes of the watershed branches were monitored realtimely.Under the constant rainfall intensity,12 rainfall experiments were conducted involving a complete combination of four kinds of rainfall intensity（25,50,75,120 mm/h）and three kinds of rainfall duration（5,10,15 min）.The experiments of variable rainfall intensity were conducted at 30-70 mm/h and 70-30-70 mm/h rainfall events.Under the constant rainfall intensity,the maximum averaged relative error of the measured values of stable flow between the automatic system measurement and the manual measurement is only 2.02%.The runoff diagrams had three obvious stages of initial runoff,stable flow and recession flow.The severe degrees of fluctuation in the processes of initial runoff and recession flow and the flow of stable flow were increased with the increasing of rainfall intensity while the duration of the stable crest segment was directly proportion to rainfall duration.The runoff processes at the watershed outlets delayed to those at the branches,but the processes no matter at the outlets or branches of the watershed were identical in shape.Under the variable rainfall intensity,the runoff processes had no stable segment and the flow changed with the rainfall intensity.The results are significantly meaningful for understanding the runoff process.The results also can provide reliable experimental support for related model research.

关 键 词：产流 过程 小流域 自动测量系统 人工降雨 

分 类 号：S271[农业科学—农业水土工程]