摘要
[目的]探讨植被对边坡固土效应的影响,为金沙江干热河谷区防治土壤侵蚀、减少水土流失提供数据支持。[方法]以云南省永仁县4种典型植被(台湾相思、锥连栎、余甘子、云南松)为研究对象,开展室内单根拉伸试验和直剪试验,研究了不同植被类型土壤抗剪性能的差异性及各因素对其的影响程度。[结果](1)4种植物平均单根抗拉力表现为:锥连栎>余甘子>云南松>台湾相思;平均单根抗拉强度表现为:余甘子>台湾相思>云南松>锥连栎;单根抗拉力与根径呈指数函数关系,单根抗拉强度与根径呈显著负相关关系。(2)在4种垂压下,4种植被根土复合体抗剪强度均大于素土,且抗剪强度指标随土层深度的变化也各不相同,云南松植被土壤黏聚力随土层深度变化变幅最大(51.47%),锥连栎植被土壤内摩擦角随土层深度变化变幅最大(37.96%)。(3)采用灰色关联法综合分析根系抗拉性能、土壤理化性质与土壤黏聚力和内摩擦角之间的关联度,其中黏聚力与根系抗拉强度关联度最高,根系抗拉力次之,含水率最低;内摩擦角与土壤容重关联度最高,有机质次之,全钾最低。[结论]植物根系抗拉性能和土壤理化性质能显著影响土壤的抗剪性能,其中根系抗拉性能对土壤黏聚力的影响较大,对土壤内摩擦角的影响不显著。
[Objective]The aims of this study are to explore the influence of vegetation on the soil consolidation effect of slope,and to provide data support for preventing soil erosion and reducing soil erosion in the dry-hot valley of Jinsha River.[Method]Four typical vegetations(Acacia confusa,Quercus franchetii,Phyllantthus emblic a,Pinus yunnanensis)in Yongren County of Yunnan Province were taken as the research objects.Indoor single root tensile test and direct shear test were carried out to study the difference of soil shear performance of different vegetation types and the influence of various factors on it.[Results](1)The average single root tensile resistance of the four plants decreased in the order:Quercus franchetii>Phyllantthus emblica>Pinus yunnanensis>Acacia confusa.The average tensile strength of single root decreased in the order:Phyllanthus emblica>Acacia confusa>Pinus yunnanensis>Quercus franchetii.The tensile resistance of a single root had an exponential function relationship with the root diameter,and the tensile strength of a single root had a significant negative correlation with the root diameter.(2)Under the four vertical pressures,the shear strength of the four vegetation root-soil composites was greater than that of the plain soil,and the shear strength index varied with the depth of the soil layer.The soil cohesion of the Pinus yunnanensis vegetation had the largest variation with the depth of the soil layer(51.47%),and the internal friction angle of the Quercus francheti i vegetation had the largest variation with the depth of the soil layer(37.96%).(3)The grey correlation method was used to comprehensively analyze the correlation between root tensile properties,soil physical and chemical properties and soil cohesion and internal friction angle.The correlation between cohesion and root tensile strength was the strongest,followed by root tensile resistance,and the water content was the weakest.The correlation between internal friction angle and soil bulk density was the strongest,followed by organic matter,and total potassium was the weakest.[Conclusion]The tensile properties of plant roots and the physical and chemical properties of soil can significantly affect the shear properties of soil,among which the tensile properties of roots have a greater impact on soil cohesion,and have no significant effect on soil internal friction angle.
作者
张珉瑞
朱少东
李盼
段青松
杨苑君
Zhang Minrui;Zhu Shaodong;Li Pan;Duan Qingsong;Yang Yuanjun(College of Water Conservancy,Yunnan Agricultural University,Kunming 650201,China)
出处
《水土保持研究》
CSCD
北大核心
2024年第4期153-162,共10页
Research of Soil and Water Conservation
基金
国家自然科学基金(32060368,31700635)
云南省应用基础研究计划项目(2018FD045)。
关键词
金沙江干热河谷
根系抗拉
抗剪性能
灰色关联法
Jinsha River dry-hot valley
root tensile
shear performance
grey correlation method
