模拟降雨条件下三峡库区紫色土坡地产流入渗特征  

Runoff and infiltration characteristics of purple soil slope in the Three Gorges Reservoir region under simulated rainfall

作　　者：曾凤铃 刘淑婧 运剑苇 常宝 鲍玲玲 刘建军 张卫华[1] ZENG Fengling;LIU Shujing;YUN Jianwei;CHANG Bao;BAO Lingling;LIU Jianjun;ZHANG Weihua(College of Resources and Environment, Southwest University, 400716, Chongqing, China;Chongqing Fuling Water Authority, 408000, Chongqing, China;Chongqing Hydroelectric Construction Survey Design Institute, 400010, Chongqing, China)

机构地区：[1]西南大学资源环境学院,重庆400716 [2]重庆市涪陵区水利局,重庆408000 [3]重庆市水利电力建筑勘测设计研究院,重庆400010

出　　处：《中国水土保持科学》2022年第1期107-113,共7页Science of Soil and Water Conservation

基　　金：重庆市社会民生类重点研发项目“渝东北小微型水利工程防治洪旱灾害关键技术研究”(cstc2018jscxmszdX0052);中央高校基本科研业务费专项“城市雨洪的水文学机理研究”(XDJK2019F002)。

摘　　要：为了研究三峡库区紫色土坡地产流与入渗特征,进一步明确在外界因素影响下的紫色土抗侵蚀程度以及坡面水量平衡关系,设置0.38、0.75和1.10 mm/min 3种降雨强度与5°、10°、15°和20°共4个坡度,采用室内人工模拟降雨系统对紫色土坡地进行降雨产流试验。结果表明:1)起始产流时间与降雨强度和坡度均呈负相关,降雨强度对产流时间的影响更大,各降雨强度下起始产流时间差异显著(P<0.05),起始产流时间随坡度的变化在小降雨强度下更明显;2)坡度15°时,各降雨强度下,径流强度与降雨历时的关系曲线呈现“S型”上升规律,在约20 min时趋于稳定,降雨强度0.38~1.10 mm/min下的稳定径流强度分别为0.32、0.39和0.73 mm/min;3)径流深与降雨强度呈正相关,与坡度呈先增大后减小的抛物线关系,其关系曲线在10°~15°之间转折;4)稳定入渗率与降雨强度呈正相关,随坡度的增加先有一定的收敛性之后增大。研究区紫色土坡地产流入渗过程受降雨强度影响明显,受坡度影响较小,研究成果可为三峡库区降雨产流过程、洪水预测预报及土壤侵蚀防治工作提供参考依据。[Background]Purple soil is one of the main types of sloping farmland in the Three Gorges Reservoir region and it causes a lot of soil erosion under the effect of rainfall and runoff and threatens the ecological security of the reservoir area.In order to further clarify the relationship between erosion resistance degree of purple soil and slope water balance under the influence of external factors,the characteristics of runoff and infiltration of purple soil slope in the Three Gorges Reservoir region were investigated.[Methods]Test materials from the purple soil test base of Southwest University was collected,and filled into the experimental tank.The artificial simulated rainfall experiments were carried out on the purple soil slope under different rainfall intensities(0.38,0.75 and 1.10 mm/min)and slope gradients(5°,10°,15°and 20°)by simulated rainfall system,each experiment was repeated for 3 times.And double ring method was used to determine the single point stable infiltration rate on the slope surface.Initial runoff generation time,runoff intensity,runoff depth and stable infiltration rate were calculated and analysized.[Results]1)Runoff generation time was negatively correlated with rainfall intensity and slope gradient,and the influence of rainfall intensity on runoff generation time was greater than that of slope gradient.The initial runoff generation time of each rainfall intensity was significantly different(P<0.05).While the change of initial runoff generation time with gradient was more obvious under light rainfall intensity.2)Under 15°slope and different conditions of rainfall intensities,runoff intensity first“S”type rose with the increase of rainfall time,and reached stability at about 20 minutes.The runoff intensity ranged from 0.38 to 1.10 mm/min and was 0.32,0.39 and 0.73 mm/min,respectively.3)Runoff depth was positive correlated with rainfall intensity,firstly increased and then decreased in a parabolic curve relationship with the slope,and there was a critical grade between 10°and 15�

关 键 词：紫色土 模拟降雨 产流特征 稳定入渗率 

分 类 号：S157.1[农业科学—土壤学]