In order to study the effects of herbs and shrubs in soil reinforcement in the cold-arid environment,the Xining Basin was chosen as the study area. Using field simulation rain testing device,the research group carried out in-situ rainfall simulations on the slopes covered by herbs Elymus nutans Griseb and Agropyron trachycaulum(Linn.)Gaertn, shrubs Caragana korshinskii Kom and Zygophyllum xanthonylon (Bunge)Maxim,and a slope without vegetation under the same test conditions was set up as the control slope. The results show that the cu-mulative runoff and cumulative sediment flux per unit area of the bare slope are bigger under the rainfall intensity of 35 mm/h,rainfall dura-tion of 90 min,with the values of 4 816.52 mL and 30.10 g;the same indexes of shrub slopes are 4 082.79 mL and 18.58 g for Zygophyllum xanthonylon,and 4 329.01 ml and 21.7 0 g for Caragana korshinskii respectively;the values of herb slopes are 3 693.18 mL and 13.92 g for Agropyron trachycaulum,and 3 469.35 mL and 10.20 g for Elymus nutans respectively. Meanwhile,the Reynolds number of the bare slope (132)and Froude number of the bare slope(0.11)are bigger than that of the slope planted with shrubs or herbs,which means that the phe-nomena of the flow erosion on the bare slope are relatively serious;the Darcy-Weisbach resistance coefficient of the slopes planted with herbs is bigger than the slopes planted with shrubs,which reflects that the inhibitory effect of herbs in resisting surface runoff is more significant than that of shrubs.%为研究寒旱环境下草本和灌木植物固土护坡作用,以西宁盆地作为研究区,采用野外模拟降雨试验装置,分别对自建试验区草本植物垂穗披碱草和细茎冰草、灌木植物柠条锦鸡儿和霸王以及裸坡开展模拟降雨试验.试验结果表明:在降雨强度为35 mm/h、降雨历时为90 min时,裸坡坡面单位面积累计产流量与累计产沙量均相对较大,分别为4816.52 mL/m2、30.10 g/m2,霸王与柠条锦鸡儿边坡的分别为4082.79 mL/m2、18.58 g/m2与4329.01 mL/m2、21.70 g/m2,垂穗披碱草与细茎冰草边坡的分别为3693.18 mL/m2、13.92 g/m2与3469.35 mL/m2、10.20 g/m2;裸坡雷诺数(平均值为132)与弗劳德数(平均值为0.11)比灌木与草本植物边坡的大,反映了裸坡坡面水流侵蚀现象最严重;草本植物边坡阻力系数比灌木边坡的大,说明草本阻滞坡面径流作用比灌木的大.
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