中文摘要：

为探讨绿竹根系固土力学机制，研究了绿竹根系在土壤中的垂直分布状况，以及绿竹单根抗拉强度和林地土壤抗剪切强度．结果表明绿竹根系干质量、长度、表面积和体积均随土层深度增加而减小，0～40 cm土层集中了90％以上的根系．径级D≤1mm根系占全部根系长度的比例最大，为79.6％，占全部根系体积的比例最小，为8．2％；而D≥2 mm根系则相反，D≥2 mm根系居于二者中间．12％含水率和饱和含水率下，绿竹根系最大抗拉力与直径呈幂函数正相关，而根系抗拉强度与直径呈幂函数负相关；不同径级根系的抗拉强度存在显著差异，D≤1 mm根系抗拉强度最大，而D≥2 mm最小．12％含水率下根系抗拉强度显著高于饱和含水率下根系抗拉强度，含水率对根系抗拉强度的影响随根系径级增大而减小．绿竹林地土壤抗剪切强度和裸地土壤抗剪切强度均随土壤深度增加而增大．绿竹林地土壤抗剪切强度与根系含量呈线性正相关，且显著大于裸地土壤抗剪切强度，其增加值与根系含量呈指数正相关，而与土壤深度关系不大．

英文摘要：

To determine the mechanism of soil stabilizing through Bambusa oldhami root system,the vertical distribution of B. oldhami root system in soil was investigated, and the tensile strengthof individual root and soil shear strength were measured in B. oldhami forest. The dry mass,length, surface area and volume of the B. oldhami root system decreased with the increasing soildepth, with more than 90% of the root system occurring in the 0-40 cm soil layer. The root classwith D ≤ 1 mm occupied the highest percentage of the total in terms of root length, accounting for79.6%, but the lowest percentage of the total in terms of root volume, accounting for 8.2%. Theroot class with D≥2 mm was the opposite, and the root class with D≥2 mm stayed in between.The maximum tensile resistance of B. oldhami root, either with 12% moisture content or a saturatedmoisture content, increased with the increasing root diameter, while the tensile strength decreasedwith the increasing root diameter in accordance with power function. Tensile strength of the root,with either of the two moisture contents, was significantly different among the diameter classes, withthe highest tensile strength occurring in the root with D≤1 mm and the lowest in the root with D≥2 mm. The tensile strength of root with 12% moisture content was significantly higher than that withthe saturated moisture content, and less effect of moisture content on root tensile strength would oc-cur in thicker roots. The shear strengths of B. oldhami forest soil and of bare soil both increasedwith the increasing soil depth. The shear strength of B. oldhami forest soil had a linear positive correlation with the root content in soil, and was significantly higher than that of bare soil. The shearstrength increment in B. oldhami forest was positively correlated with the root content in soil accord-ing to an exponential function, but not related significantly with soil depth.