摘要
为明确干旱矿区侵蚀发生后折力损伤对植物根系力学特性的影响及其受损后的自修复机制,利用HG100数显式推拉力计和自制便携式试验机台,对小叶锦鸡儿1-4 mm径级直根和侧根分支处未受损及受损自修复后的抗折力学特性进行研究。结果表明：（1）生长季初期,未受损小叶锦鸡儿根系极限抗折力与根径呈幂函数正相关,抗折强度与根径幂函数负相关,直根极限抗折力和抗折强度均大于侧根分支处;（2）折力损伤会明显抑制根系正常生长,小叶锦鸡儿根系受损自修复后,活性、生长量和保存率均低于平行对照,根径和根型均是影响这种抑制作用的重要因素,侧根分支处活性和保存率在受损后的减少程度显著大于直根;（3）小叶锦鸡儿根系受损自修复后,极限抗折力与抗折强度相比,生长季初期有所增加,但外力损伤会显著阻碍这种增长,导致其增长率显著低于平行对照,3个月后极限抗折力修复率为48. 91%,抗折强度修复率为57. 59%,说明根系受损后不会彻底丧失固土能力,通过自修复可以逐步恢复原有功能,但短期内自修复程度有限。直根极限抗折力修复率为60. 55%,侧根分支处仅为36. 34%,说明在同等外力荷载条件下,小叶锦鸡儿直根受损自修复能力显著大于侧根分支处,具备更强的再次抵御外力破坏的能力。
In this study,the HG100 digital push pull tester and self-developed experimental installation were used to investigate the anti-fracture mechanical properties of tap roots（ diameter was 1-4 mm） and lateral roots of Caragana microphylla before and after occurring the fracture force injury. The purposes of the study were to clarify the effects of fracture force injury on mechanical properties and self-healing mechanism of plant roots after soil erosion occurred in the Shendong diggings. The results indicated that：（1） There was a positive power function correlation between the root ultimate anti-fracture force and root diameter of C. microphylla in early growth season,but a negative one between the anti-fracture strength and root diameter. Moreover,the ultimate anti-fracture force and strength of tap roots were higher than that of lateral roots.（2） The fracture force injury restricted significantly the normal growth of roots,and the activity,growth and survival rate of C. microphylla roots after self-healing were all lower than those of contrast. Root diameter and root type were the important factors affecting evidently such restriction,the activity and survival rate of lateral roots were decreased more significantly than those of tap roots after injured;（3） The ultimate anti-fracture force and strength of C. microphylla roots were increased to some extent after self-healing compared with those in early growth season,but such increase was restricted by the external injury,and the growth rate was significantly lower than that of control. The self-healing rates of ultimate anti-fracture force and strength after three months were 48. 91% and 57. 59% respectively. In conclusion,the root system could not completely lose its soil reinforcement capability after injured,the original function could be restored gradually through self-healing capability. The self-healing rates of tap roots and lateral roots were 60. 55% and 36. 34% respectively,which showed that the self-healing capability of tap roots was obviously higher than that of lateral roots.
作者
王博
刘静
王晨嘉
张欣
李强
刘嘉伟
张强
WANG Bo;LIU Jing;WANG Chen-jia;ZHANG Xin;LI Qiang;LIU Jia-wei;ZHANG Qiang(College of Desert Control Science and Engineering,Inner Mongolia Agricultural University,Hohhot 010019,Inner Mongolia,China;Institute of Water Resources for Pasturing Area,Ministry of Water Resources,Hohhot 010019,Inner Mongolia,China;Environmental Management Office,Shendong Coal Group,Ejin Horo Banner 017200,Inner Mongolia,China)
出处
《干旱区研究》
CSCD
北大核心
2018年第6期1459-1467,共9页
Arid Zone Research
基金
国家自然科学基金资助项目(51364034)
内蒙古自治区研究生科研创新资助项目(B20171012907Z)
作者简介
王博（1989-），男，博士研究生，主要从事矿区水土流失防治和生态恢复．E—mail：wbbrave@163．com;通讯作者：刘静．E-mail：Ljing58@126．com
