Study On The Erosion Resistance Of The Root System Soil Under Different Plant Slope Protection Mode

Most surface soil of Qitai highway subgrade slope is sandy soil. The concentrated rainfall usually causes subgrade landslides and soil erosion. In our study, we selected5kinds of shrubs and6kinds of herbs and established3plant slope protection modes, then, we discussed the soil-hold effectiveness of different modes by using undisturbed-soil trough scouring method for Soil anti-scourability enhancement and hydrostatic collapse method for soil anti-erodibility. and using principal component analysis analyzed the factors which related to soil corrosion resistance. The main research results are as follows:Amorpha fruticosa is the best type for soil anti-scourability and soil anti-erodibility enhancement effect in single shrub mode. Lolium perenne is the best type for soil anti-scourability enhancement effect and Medicago saliva and Echinochloa crusgali are the best types for soil anti-erodibility enhancement effect in single herb mode. Amorpha fruticosa-Medicago sativa. Amorpha fruticosa-Lolium perenne, Tamarix chinensis-Lohum perenne are the best types for soil anti-scourability enhancement effect and Amorpha fruticosa-Medicago sativa is the best type for soil anti-erodibility enhancement effect in shrubs and herbs mode. We filtered the alternative types for vegetation restoration and soil and water conservation on the Qitai highway. We selected Amorpha fruticosa. Hedysarum fruticosiim var. mongolicum in single shrub mode. Lolium perenne, Medicago sativa. Echinochloa crusgali in single herb mode. Amorpha fruticosa-Medicago sativa, Amorpha fruticosa-Lolium perenne, Tamarix chinensis-Lolium perenne. Caragana microphylla-Trifolium repens in shrubs and herbs mode. Generally speaking, the soil anti-scourability and soil anti-erodibility increased with the increase of the soil depth. The relationship between the soil erosion index (S) and the immersion time (t) is a three times function curve in each different species and combination. Shrubs and herbs mode is better than single type mode in different modes.>3mm root biomass.<1mm root length,>3mm root length, Organic matter are all riding key roles on the soil anti-scourability enhancement effect.<1mm root biomass.>5mm and2-3mm large soil aggregates are all riding key roles on the soil anti-erodibility enhancement effect.