乔木侧根对土体的斜向牵引效应 Ⅰ原理和数学模型  

TRACTION EFFECT OF LATERAL ROOTS OF TREES ⅠPRINCIPLE AND CALCULATION

作　　者：周跃[1,2] 徐强[1,2] 络华松 李玉辉 

机构地区：[1]云南省地理研究所 [2]云南教育学院地理系

出　　处：《山地学报》1999年第1期4-9,共6页Mountain Research

基　　金：国家自然科学基金;云南省应有基础研究基金;云南省科委主任基金;国家教委留学回国人员科研启动基金;英中文化协会联合资助

摘　　要：为证实植物侧根对周围土壤的斜向牵引效应是乔木根系抗蚀护坡机械效应的重要内容，以云南松林为例对这种效应及其量值进行了野外观测和模型计算，并对其在克服林地浅层坡面的不稳定性以及控制侵蚀保护坡面的作用进行了讨论。The use of vegetation has been a major approach in tackling the even more serious erosious problem in the upper stream of Yangtze River,Southwest China.An indigenous pine tree( Pinus yunnanensis French,called ‘Yunnan Pine’)has been used as one of the best and most highly_recommended species for this purpose,because its suitable bio_ecological characteristics.During the last few years,large areas of suitable mountain slopes have been reforested,using this pine tree. However, the mechanical effect of this tree on erosion control is not clear,and lack of this knowledge has greatly hampered research and practice in conservation,using the pine forest.There is,therefore,a great and urgent need to investigate the role and the effects of the Yunnan pine,and this need is addressed in this paper. A traction effect,arising from mechanical interaction between lateral roots and the soil,refers to the mechanical effect of lateral to horizontal roots,normally in shallow soil,to enhance the in_plane tensile strength of soil in the rooted soil zone.It is an important aspect of soil reinforcement,and believed to exist also in the Yunnan pine trees,which could be able to provide stabilizing role on the rooted soil,through their traction effect.This study further developed a model for quantifying the root traction effect,based on some previous models,which quantify the mechanical interaction between soil and single roots being extracted from the soil.To quantify the traction effect of the Yunnan pine,a mumber of coefficients were obtained from field.The quantification of this kind and the model developed are used for the first time in the world,and some preliminary results have been achieved. Accrding to some field samplings,the result indicates that the force required to break thin roots rises rapidly with an increase to the root diameter,and the root tensile strength decreased as the diameter increase.A mathematical strength_diameter relationship was obtained,with which and the examining results of root distri

关 键 词：乔木根系 牵引效应 侵蚀控制 土壤 云南松 

分 类 号：S157.1[农业科学—土壤学] S791.257[农业科学—农业基础科学]