Search

The effects of plant roots on the increase in soil shear strength involve a complex interaction of mechanical and hydrological processes operating over a scale of very diverse root architecture. Understanding the effects of mechanical mechanisms on soil shear strength is challenged by this inherent complexity. A high level of inaccuracy in field measurements of soil reinforcement makes field measurements much more challenging than that of indoor observations. This paper presents a simple experimental study where the shear strength of undisturbed soil is measured at different soil depths and at different distances from the main stems of 7 tree species, a bamboo, a herbaceous perennial, perennial grass and a fern by measuring their root area ratio, diameter class, and tensile strength. The result confirms that root distribution varies widely within root diameter classes and root area ratio between species and soil layers. Root architecture characteristics were the dominant factors influencing shear strength in the 0.2–0.4 m soil layer. In the process of vegetation restoration, O. compositus and H. fulva were used as colonizing vegetation. Later, S. lucida and L. kwangtungensis were recommended to stabilize the shallow soil in the Three Gorges reservoir region.