干旱区生态环境知识资源中心(Arid): 寒旱环境盐生植物根-土复合体抗剪强度影响因素试验研究

Arid

	寒旱环境盐生植物根-土复合体抗剪强度影响因素试验研究
其他题名	EXPERIMENTAL RESEARCH ON FACTORS AFFECTING SHEAR STRENGTH OF HALOPHYTE ROOT-SOIL COMPOSITE SYSTEMS IN COLD AND ARID ENVIRONMENTS
	祁兆鑫; 余冬梅; 刘亚斌; 付江涛; 胡夏嵩; 李淑霞; 赵丹
来源期刊	工程地质学报
ISSN	1004-9665
出版年	2017
卷号	25 期号:6 页码:1438-1448
中文摘要	为探讨寒旱环境盐生植物根系对增强土体抗剪强度的贡献,本项研究以柴达木盆地尕斯库勒盐湖区及其周边地区作为试验区,选取区内海韭菜(Triglochin maritimum Linn.) 、芦苇(Phragmites australis Trin.) 、无脉苔草(Carex enervis C. A. Mey.) 、赖草(Leymus secalinus Tzvel.) 、洽草(Koeleria cristata(L.) Pers.) 5种优势盐生草本植物作为供试种,通过野外采集根-土复合体原状和不含根系的素土试样,且由表层向下层分层制取直剪原状试样方法,分别进行复合体和素土试样的室内直剪试验,分析不同取样位置深度处的含水量、垂直压力、根系分布形态、含根量以及根面积比5种因素对根-土复合体抗剪强度的影响。试验结果表明:随着取样深度位置处土体含水量增加,复合体黏聚力c值呈逐渐降低变化规律; 5种植物根-土复合体和素土试样垂直压力和抗剪强度之间符合莫尔-库仑准则,5种植物根系起到浅层加筋作用且抗剪强度增幅为3.26%~ 57.18%。随着海韭菜和芦苇根-土复合体试样的根面积比(RAR)及无脉苔草、赖草和洽草根-土复合体试样含根量的减小,复合体试样黏聚力c值呈降低趋势;根面积比对海韭菜和芦苇根-土复合体黏聚力c值的影响程度,以及含根量对无脉苔草、赖草和洽草根-土复合体黏聚力c值的影响程度均相对大于含水量。5种植物根-土复合体在不同深度处黏聚力c值均显著高于素土黏聚力c值,其增强幅度为9.61%~ 182.56%,相比较而言,内摩擦角phi值变化相对较小。区内海韭菜根系对土体抗剪强度的增强作用相对较为显著,其次为芦苇、无脉苔草、赖草、洽草。该项研究结果对于进一步评价盐生植物根系增强土体强度作用,以及与试验区地质条件相类似的地区采用盐生植物有效防止水土流失、浅层滑坡等地质灾害具有实际指导意义。
英文摘要	This paper aims to study the contribution of halophytes roots in increasing shear strength of soil in cold and arid environments. The Gasikule Salt Lakes and the surrounding areas in the Qaidam Basin are selected as the test area. Five predominant halophytes (Triglochin maritimum Linn.,Phragmites australis Trin.,Carex enervis C. A.Mey.,Leymus secalinus Tzvel.,Koeleria cristata (L.) Pers.) are selected as test species. Direct shear tests are carried out to the samples of soil without roots and root-soil composite system collected in-situ by the method of digging soil from shallow layers to the deep layers of the ground,where layer-by-layer excavation is applied to investigate the effect of moisture content,vertical pressure,the pattern of roots arrangement,root content and root area ratio on shear strength of soil. Results exhibit the following results. With the increasing of soil moisture content,the cohesion force decline. The relationship between vertical pressure and shear strength satisfies Mohr-Coulomb law. The roots play a role in soil reinforcement in shallow layer. The increment amplitude of shear strength is 3.26%~57.18%.With decreasing in root area ratio(RAR) for T.maritimum Linn. and P.australis Trin. and the decreasing in root content for C.enervis C.A.Mey.,L.secalinus Tzvel. and K.cristata(L.) Pers., the cohesion force of root-soil composite system decreases. Root area ratio(RAR) has a relatively larger effect on cohesion force of T. maritimum Linn. and P. australis Trin. root-soil composite system than soil moisture content. The effect of root content on cohesion force of C. enervis C.A.Mey.,L. secalinus Tzvel. and K. cristata(L.) Pers. root-soil composite system is bigger than soil moisture content,too. The cohesion force of root-soil composite system at different depths is significantly larger than that of non-rooted soil,with the corresponding increment amplitude ranging from 9.61% ~182.56%. In contrast,the variation in internal friction angle is relatively small. Reinforcement effect of shear strength for T.maritimum Linn. roots is relatively significant,followed by P. australis Trin.,C. enervis C.A.Mey.,L. secalinus Tzvel. and K. cristata (L.) Pers. The conclusion plays a role in assessing the reinforcement of roots in increasing shear strength and has an instructive meaning in implementing measures in soil erosion prevention and shallow landslide and other such geological hazards by halophytes in testing site and other regions with similar geological conditions.
中文关键词	寒旱环境 ; 盐生植物 ; 根-土复合体 ; 黏聚力 ; 内摩擦角 ; 抗剪强度
英文关键词	Cold and arid environments Halophytes Root-soil composite system Cohesion force Internal friction angle Shear strength
语种	中文
国家	中国
收录类别	CSCD
WOS类目	MINERALOGY
WOS研究方向	Mineralogy
CSCD记录号	CSCD:6148841
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/236113
作者单位	中国科学院青海盐湖研究所, 青海省盐湖地质与环境重点实验室, 西宁, 青海 810008, 中国
推荐引用方式 GB/T 7714	祁兆鑫,余冬梅,刘亚斌,等. 寒旱环境盐生植物根-土复合体抗剪强度影响因素试验研究[J],2017,25(6):1438-1448.
APA	祁兆鑫.,余冬梅.,刘亚斌.,付江涛.,胡夏嵩.,...&赵丹.(2017).寒旱环境盐生植物根-土复合体抗剪强度影响因素试验研究.工程地质学报,25(6),1438-1448.
MLA	祁兆鑫,et al."寒旱环境盐生植物根-土复合体抗剪强度影响因素试验研究".工程地质学报 25.6(2017):1438-1448.