土壤水分对植物根系固土力学性能的影响综述

Review on the Effects of Soil Moisture on Mechanical Properties of Soil Reinforcement by Plant Roots

为了分析土壤水分对植物根系固土力学性能的影响机制,揭示根系固土力学机理和科学防治土壤流失提供基础理论研究思路,分析了土壤含水量对根系分布、根系抗拉特性、根系-土壤相互作用、根系-土壤复合体抗剪特性和根系固土力学模型的影响,探讨了根系固土力学性能对土壤含水量的响应机理研究现状及发展趋势。认为根系形态与根系固土效果紧密相关,目前缺乏土壤水分对根系形态及根系固土力学特性的定量研究;对根系抗拉强度和拔出强度的影响因素等关注较多,但对土壤水分变化是否影响根系强度、根土界面摩擦和根系破坏模式研究非常少;土壤水分在植物固持水土的水文效应中研究较多,但其对根系固土力学性能的影响规律尚需进一步研究;评价根系固土力学性能的模型没有考虑或充分考虑土壤水分变化对固土效果的影响,且模型中各影响因素的相对重要性关系尚不清楚。分析结果深化了对降水影响覆盖植被边坡稳定性机理的理解,为深入研究土壤水分与根系固土力学机制相互作用提供了理论基础。

In order to analyze the mechanism of soil moisture influencing the mechanical properties of soilreinforcement by plant roots, to reveal the mechanism of soil reinforcement by plant roots and scientificallyprevent soil erosion, effects of soil moisture on root distribution, root tensile strength, root- soil interaction,shear properties of root- soil composites and mechanical models of root reinforcement were analyzed. Thepresent status and trend of mechanical properties of soil moisture on soil reinforcement by plant roots werediscussed. The results indicated that root distribution was closely related to the effects of soil reinforcement byroots. However, quantitative research on relationships between soil moisture and root distribution and soilreinforcement was still insufficient. The influence of soil moisture on failure patterns of roots in shearing soilsand on the mechanical effects of root reinforcement were still unclear, although it was considered in thehydraulic effects of soil reinforcement by plant roots. Besides, the existing mechanical models of root reinforcement were established without considering or sufficiently integrating with soil moisture, and therelative importance of the influencing factors was unclear. The results improved the understanding of themechanism of rainfall on stability of slopes covered by plants, and provided theory basis for further research oninteraction between soil moisture and soil reinforcement by plant roots.