内蒙古中西部3种乡土植物根系抗拉力学特性的对比研究  

Root Tensile Mechanism Comparison of Three Aboriginal Plants in Central-western Inner Mongolia Area

作　　者：左志严 格日乐[1] 乌仁图雅[1] 王娟[1] 

机构地区：[1]内蒙古农业大学生态环境学院,内蒙古呼和浩特010019

出　　处：《水土保持通报》2015年第2期52-57,63,共7页Bulletin of Soil and Water Conservation

基　　金：国家自然科学基金项目"准格尔露天煤矿排土场水土保持功能植被固土抗蚀生物力学响应机制"(41161046)

摘　　要：[目的]研究内蒙古中西部地区3种乡土植物种根系的抗拉机理,为该区水土保持的树种选择提供依据。[方法]以内蒙古中西部地区3种常见植物柠条、沙棘和紫花苜蓿根系为对象,进行室内单根瞬时极限拉伸试验研究。[结果](1)3种植物单根极限抗拉力随着直径的增加而增大,单根极限抗拉强度随直径的增加均呈幂函数递减。(2)当直径在0.19mm^2.89mm范围内相同径级时,3种植物单根极限抗拉强度和弹性模量均值大小顺序相同,依次为:柠条>沙棘>紫花苜蓿,3种植物根径≤0.5mm的细根具有较大的极限抗拉强度和弹性模量;(3)同一树种当根系直径相同时,土壤含水率高则其单根平均极限抗拉强度小。[结论]根系的力学特性与形态结构特征的结合,是选择适宜的水土保持树种非常重要的因素。从根系抗拉性能方面评价3种植物根系固土抗蚀能力大小则柠条优于沙棘和紫花苜蓿。[Objective]Root tensible mechanism of three aboriginal plants in the Central-western Inner Mongolia area was studied to provide references of species selection for soil and water consvervation.[Methods]Single root tension of three common plants of the midwest regions of Inner Mongolia area,Hippophae rhamnoides,Caragana korshinskii and Medicago sativa were tested with indoor instantaneous ultimate method.[Results]（1）Single root transient ultimate tensile strength of the plants increased with diameter;single root ultimate tensile strength decreased by power function with diameter increased;（2）When the root diameters were in the same size class between 0.19~2.89 mm,three species＇ single root transient ultimate tensile strength and modulus of elasticity ranked as：Hippophae rhamnoides〉Caragana Korshinskii〉Medicago sativa when the three plants＇ root diameter were less than 0.5mm,the fine root had greater ultimate tensile strength and modulus of elasticity;（3）When the same tree species had the same root diameter,if soil had high moisture content,the average tensile strength of single was small.[Conclusion]It is important to consider both morphological characteristics and mechanical properties when choosing appropriate species for soil and water conservation.The levels of root reinforcement erosion resistance of Caragana korshinskii were better than that of Hippophae rhamnoides and Medicago sativa.

关 键 词：单根 极限抗拉力 极限抗拉强度 弹性模量 土壤含水率 

分 类 号：S714.7[农业科学—林学]