针叶与阔叶树根系对土壤抗剪强度及坡体稳定性的影响  

Effects of Acerola and Broad Leaved Tree Roots on Soil Shear Strength and Slope Stability

作　　者：李云鹏[1] 张会兰[1] 王玉杰[1] 王云琦[1] 朱锦奇[1] 刘勇[1] 

机构地区：[1]北京林业大学水土保持学院,北京100083

出　　处：《水土保持通报》2014年第1期40-45,共6页Bulletin of Soil and Water Conservation

基　　金：中央高校基本科研业务费专项基金项目“水土保持生态工程坡面稳定性机理研究”(TD2011-01)

摘　　要：重庆缙云山地处三峡库区,是国家重点自然保护区。由于地势特点,坡面极易发生土壤侵蚀及浅层滑坡,因此,在不破坏原有生态环境的前提下,有效防止灾害发生是该地区的重点防治工作。选取了同种根构型的针叶树种(马尾松Pinus massoniana Lamb)和阔叶树种(四川大头茶Gordonia acuminate),比较其提高土壤抗剪强度的作用强弱,并分析根面积比率、剪切带根系径级比、根系位置范围,以及根系角度等因素对土壤抗剪强度的影响。结果表明,针叶树种对土壤抗剪强度增强效果强于阔叶树种;针叶树种根系平均抗拉强度较大,其对土壤抗剪强度的增量更大;针叶树种根系分布范围较广且存在更多与剪切方向成60°的根系,表现出更好的固坡作用;根面积比率对土壤抗剪强度影响不明显。Located in the Three Gorges Reservoir area, the Jinyun Mountains of Chongqing City is the national natural reserve. Due to the topographic characteristics, soil erosion and shallow landslides are easy to occur on slope. Therefore, effective disaster prevention without destroying original ecological environment is the key control work in this region. Pinus massoniana Lamb as Coniferous species and Gordonia acuminate as broad-leaf species, with the same root architecture, were selected, and their relative effects on the increment of soil shear strength were compared. Effects of crucial factors, e. g. , root area ratio, shear zone root diameter level, spectrum of root position and angle distribution, on the shear strength were further discussed. Results show that the soil reinforcement effect for coniferous species was greater than those for broad-leaf species. The greater averaged tensile strength of coniferous tree led to a larger increment of soil shear strength. The coniferous species, presenting better steadiness on slope, had a larger spectrum of root position distribution and a greater amount of roots at an angle of 60° with shear direction. Effect of the root area ratio to soil shear strength is not notable.

关 键 词：根构型 根系分布 土壤抗剪强度 边坡稳定 

分 类 号：S714[农业科学—林学]