嫩江大堤植物根系固土护堤功能研究

Soil fixation and Dyke Revetment Function of Plant Root System in NenJiang Dyke

通过对嫩江大堤护坡植物根系及土壤抗冲、抗蚀及抗剪强度的测定分析，发现同一地段土壤的抗冲、抗蚀（水稳性）指数及抗剪强度均是表土层大于底土层。植物根系有较强的固持土壤功能，抗冲指数与根长、根量间有明显的相关性，单相关系数分别为０．９１４６和０．８１９７。有机质含量高的土壤抗蚀性强，水稳性指数大。水稳性指数与有机质含量间的相关系数为０．９１３２，与根长和根量的相关性相对较低，单相关系数分别为０．８３１７和０．８０９１。土壤稳定性与植物根量关系密切，根量大，其抗剪强度就大，相关系数为０．９８１４。在现有的植物中，牛毛草地抗蚀能力最大，其固土护坡护堤功能最强。

Through analysis on root system, soil antiscour, antierosion and shear strength determination of slope protection plant on the Nenjiang dyke, the results show that, in a same section, soil antiscour and antierosion (water stablility) index and shear strength of surface soil layer are all larger than that of base soil layer. Plant root system has rather powerful strength of soil fixation function, the antiscour index has clear coherence with root length and root quantity, the single cohere coeffcients are 0.9146 and 0.8197 respectively. Soil antierodibility is better and water stable index are bigger as soil organic matter content is higher, the cohere coefficient between them is 0.9132, the cohere coefficient of it with root lenght and root quantity are comparatively rather low, the single cohere coefficient are 0.8317 and 0.8091. Plant root quantity has a great bearing upon soil stability, the cohere coefficient of it with shear strength is 0.9814. In the plants now available on Nenjiang dyke, the antierodibility of Carex duriuscula C.A.Mey is greatest, its soil fixation and dyke revetment and slope revetment function are most strong, so it should be given a energetic spread in the same areas.