Study On Mechanical Characteristics Of Roots Of Seven Plant Species

From July 21 to 22,2013,a large-scale landslide caused by heavy rain occurred in Baota District,Yan'an City,Shaanxi Province.The landslide distribution and vegetation distribution were consistent in all areas,and the landslide occurred on the southeast slope of small trees.The number is larger and the area is larger;on the contrary,the landslide occurs on the northwest slope of large trees and the area is small.In order to explore the effects of different plants on the prevention and control of shallow landslides,this study analyzed the stability of single-slope slopes under the action of seven soil and water conservation plants in Baota District,Yan'an City,Shaanxi Province,combined with the morphological and mechanical characteristics of the root system.Under the action of soil characteristics,the effects of different plants on the prevention of superficial landslides were explored and the following conclusions were obtained:(1)The distribution of plant root length in different diameter ranges can be expressed by an exponential function;plant root characteristic diameter Dc can reflect plant root architecture to a certain extent.(2)The roots of 7 plantes all have good tensile strength.The coefficient in the fitting relationship between root tensile strength and root diameter is between(19.237,69.631)and the index is between(-1.226?-0.395);there is a big difference between the single tensile strength and the diameter of different plants;there is a big difference between the single tensile strength and the diameter of different plants.(3)The roots of 7 plant species can greatly improve the soil cohesion,and the additional cohesive force of the 7 plant roots is also very different;Compared to Caragana arborescens Lam.,Vitex negundo var.heterophylla(Franch.)Rehd.and Hippophae rhamnoides Linn.,Ziziphus jujuba Mill.var.spinosa(Bunge)Hu ex H.F.Chow,Ulmus pumila Linn.,Platycladus orientalis Franco,Rhus typhina Linn.provides greater cohesion,(4)There are obvious differences in the effects of each plant on the stability of the slope,the highest in the elm and the lowest in the torch.The effects of different plants on the prevention of shallow landslides caused by rainfall are quite different;the slopes under the action of plants such as Torch,Caragana,and Vitex have lower slope stability;and the slope safety under the action of eucalyptus The coefficient of elasticity is the highest,and its effect on preventing superficial landslides is the best.