摘要
以紫穗槐、胡枝子及狗牙根根系及其与土壤构成的根—土复合体为研究对象,通过对根—土复合体的室内直剪试验,比较分析了不同物种根系和不同含根量对根—土复合体的抗剪强度的影响。结果表明,根系的存在提高了土体的抗剪强度,根—土复合体的抗剪强度随着含根量的增加而增大,但当含根量达到一定值时根—土复合体的强度增加并不明显,即存在最佳含根量范围;与无根扰动土相比,根—土复合体内摩擦角无显著变化,但显著提高了黏聚力,其中紫穗槐、胡枝子、狗牙根黏聚力平均增幅分别为47.5%,39.2%和38.9%;紫穗槐、胡枝子和狗牙根根—土复合体对土壤的抗剪强度影响不同。在水土流失区种植乔灌木物种能有效增加坡体稳定性,降低土壤侵蚀。
Amorpha fruticosa, Leapedeza and Cynodon dactylon, as well as their root soil composites, were used as the research objects, a comparative analysis was made for the effects of different root contents and plant roots on the shear strength of rootsoil composite through laboratory shear tests. Results showed that the shear strength was enhanced by roots and increased with the increased root amount. However, if root amount reached a certain value, the shear strength of rootsoil composite did not increase obviously, i. e. , there is an optimum range of root amount. Compared with the cohesion of soil without roots, there was no significant change in the internal friction angle of rootsoil composite, but the cohesion was greatly in creased. The increased percentages of cohesion for Amorpha fruticosa, Leapedeza and Cynodon dactylon were 47.5%, 39.2% and 38.9%, respectively. The effects of the rootsoil composites of Amorpha frutico sa and Leapedeza and Cynodon dactylon on the shear strength were different. This implies that planting shrub species could effectively increase slope stability and efficiently reduce soil erosion in the regions suffer ing from soil and water loss.
出处
《水土保持通报》
CSCD
北大核心
2013年第5期118-122,共5页
Bulletin of Soil and Water Conservation
基金
国家自然科学基金项目"喀斯特植物磷
钙胁迫的生态适应性调控机制研究"(31100187)
贵州省"环境科学"省级特色重点学科专项科研项目"不同植物根-土复合体提高边坡土体抗剪切强度的试验研究"(HJKX201201)
贵州师范学院自然科学研究基金项目"草本植物根系控制水土流失的抗拉强度研究"(GZSY201122)
贵州省环境科学教学团队项目(黔教高[2012]426号)
贵州师范学院环境科学教学团队项目(贵师院[2012]47号)
