泥石流源区典型草本植物根系抗拉试验  

Root Tensile Test of Typical Grass in Debris Flow Triggering Area

作　　者：陆桂红[1,2] 欧国强[1] 杨顺[1,2] 王钧[1,2] 宇岩[1,2] 

机构地区：[1]中国科学院山地灾害与地表过程重点实验室/中国科学院水利部成都山地灾害与环境研究所,四川成都610041 [2]中国科学院大学,北京100049

出　　处：《山地学报》2014年第6期725-731,共7页Mountain Research

基　　金：水利部公益性行业科研专项(NO.201301058);中国科学院山地灾害与地表过程重点实验室自主资助项目;科技部国际合作项目(批准号:20133DFA21720)~~

摘　　要：植被对于泥石流源区的生态修复和物源稳定具有重要意义,其中植物根系的抗拉力学特性是影响植物护坡的主要因素之一。为了探究泥石流源区植物根系的抗拉特性,以都江堰市锅圈岩泥石流源区为研究区,在野外调查的基础上,通过重要值计算确定了源区典型草本植物并进行抗拉强度试验。研究表明,锅圈岩泥石流源区主要分布有寒芒、节节草等对恶劣环境适应性强的乡土植物,它们的根系平均分布深度在30 cm以内;根系抗拉力与根径呈幂函数正相关关系,抗拉力随根径的增大而增大。当根径>0.50 mm时,抗拉强度与根径也表现出幂函数关系;当根径<0.50 mm时,部分植物根系的抗拉强度值波动较大。不同植物根系的平均抗拉强度从大到小依次为铁杆蒿(106.24 MPa)、节节草(非节点处,30.79 MPa)、草地早熟禾(28.69 MPa)、小飞蓬(20.20 MPa)、多头苦荬(18.77 MPa)、寒芒(老根,14.87 MPa)、节节草(节点处,12.67 MPa)、寒芒(新根,8.29 MPa)。泥石流源区草本植物的根系抗拉力学特性良好,对稳固浅层土体和泥石流物源有积极作用。Plant roots play an important role in slope vegetation and stability in debris flow triggering area. And root tensile property is one of the major factors affecting slope protection of plants. In order to explore the root tensile properties of plants in debris flow triggering area, this paper took Guojuanyan debris flow triggering area in Dujiangyan Sichuan, China for the study area. Based on field survey and significant values, the typical plants species were determined and their root tensile tests were carried out. Studies have shown that Guojuanyan debris flow triggering area was mainly distributed with indigenous plants daptable and with an average root depth of 30 cm such as Miscanthus floridulu and Commelina diffusa. They are aor less. These plant roots＇ tensile force presented power function with root diameter and had good correlation. When the root diameter was greater than 0.50 mm, the tensile strength and root diameter could also be fitted with power function. When the root diameter was less than 0.50 mm, the tensile strength values of some plant roots fluctuated largely. And the average tensile strength in order were Artemisia sacrorum （106.24 MPa） , Commelina diffusa （non-node, 30.79 MPa）, Poa pratensis （28.69 MPa）, Conyza canadensis （20.20MPa）, long Kumai （18.77 MPa）, Miscanthusfloridulu （old roots, 14.87 MPa）, Commelina diffusa （node, 12.67 MPa）, Miscanthusfloridulu （new roots, 8.29 MPa ）. Root tensile mechanical properties of herbs performed well, indicating that they can play efficiency in shallow slope stability and reduce debris provenance.

关 键 词：泥石流源区 典型植物 抗拉力 抗拉强度 

分 类 号：S157.2[农业科学—土壤学]