摘要
通过对黄土地区生长的灌木——柠条(Caragana korshinskii)根系作原位水平挤出法剪切测定结果,提出了以单位剪切面积(A)中直径大于0.4cm 的各根系横截面积之和(A_R)所占比重(A_R/A)大于0.1%,为判定林木根系固坡力学强度有效范围的定量指标值。并通过室外拉拔测试得出,乔木树种白榆固坡有效深度(H_(R.f))与地径(D_0)的关系式为H_(R.f)=0.294+0.068D_0(r=0.906)从而解决了具有垂直根系的林木固结土坡有效深度和宽度界限的判别值与经验式,并提出了白榆根系固坡力学强度参数值。作者进一步提出在 A_R 值一定时,根系规格与分布以长而粗的格局为最佳组构方式。但生长快而分布密集的细根对防治土壤面蚀有重要意义。
The paper has put forward two relations that can be used to determine the effective limits of the tree and bush’s roots strength in stable slopes.One is the relation ratio of the soil cross—sectional area A occupied by total roots area At(the shearing diameter more than 0.4cm)as follows:A_R/A≥0.1% which obtained by directly shearing roots of Caragna korshinskii, another is the relation between the fixing slope effective depth (H_(r.f))and the surface ground diameter(D_o),which obtained by pulling roots(the complex μ_x method)of Ulmus pumila,as follows: H_(r.f)=0.294+0.068D_o...(r=0.906) According to the comeplex μ_x method,the author has obtained the parameter(H_(r.f),B_(r.f),Δτ_R and so on)of Ulmus Pumila roots strength in fixing slopes.At same time,the author adopt calculating method of pulling roots and pointed out that the best distribution of roots for fixing slopes is formed by long and wide roots.The studying results provide scientific basis for production and projecting pattern of planting the tree and bush in fixing slopes.
出处
《水土保持学报》
CSCD
北大核心
1990年第1期17-24,共8页
Journal of Soil and Water Conservation
关键词
乔木
灌木
根系
固坡力学强度
范围
root system of C.korshinskii
machanics strength in fixing slope distrifution of roots
root soil
