嫩江大堤植物根系固土护堤功能研究

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，土壤抗蚀性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８１３７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，应大力推广。

Study of Dyke Protection by Soil Solidification of Plant Root System in Nenjiang River

Through the measurement and analysis of plant root system for Nenjiang river dyke protection and soil anti scour,anti erosion strength and shearing strength,the anthor find that the surface soil is stronger that the bottom soil at the same site in shearing strength as well as higher anti scour and anti erosion.Since plant root system is of strong soil solidification function, the soil anti scour index is of evident relation to root length and root volume with single correlation coefficients of 0.914 6 and 0.819 7 respectively. The soil with higher organic material content has stronger anti scour strength and higher stablity in water. Soil anti erosion strength is of lower correlation to organic material content than that to root length and root volume with the correlation coefficient of 0.913 2 and single correlation coefficients of 0.813 7 and 0.809 1 respectively. Soil stability is of close relation to plant root volume with correlation coefficient of 0.981 4, i.e., the more the root volume is, the higher the soil shearing strength is. Soil with growth of Needle Spikesedge, type of grass, is of the highest anti erosion strength in comparison to existing vegetation with the strongest slope and dyke protection capacity, and is worth of wide extension.