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缙云山地处三峡库区附近,坡面侵蚀以剪切破坏为主。选取缙云山5个标准样地,通过研究各个林地类型内土壤临界剪切力随深度的变化以及测量多个土壤物理性质指标,得出不同林地抵抗剪切破坏能力的强弱关系和这些指标对不同林地土壤抗剪能力的影响以及主次关系。结果表明,在每个林地中,原状土的临界剪切力随深度的增加而增加;通过库伦公式得出的土壤抗剪强度与土壤临界剪切力的回归方程为:y=4.372 x2+29.03(R2=0.813,n=25)。对于同一林地,在楠竹林中,土壤孔隙是影响临界剪切力的主要因素,在常绿阔叶林中却是土壤含水率,而对于其他三个林地,均为土壤结构指标与土壤临界剪切力的相关性最大;对于土壤临界剪切力和土壤抗剪强度,不同物理指标的组合影响是变化的。但总的来说,在不同林地中,相同土壤物理指标对抗剪能力的影响基本是一致的。
Jinyun Mountain is located in the vicinity of the Three Gorges reservoir area, slope erosion mainly to shear failure. The five standard plots of Jinyun Mountain were chosen to study the relationship between the critical shearing force and depth of different soil types and to measure the physical properties of multiple soils. Effect of Shear Soil Shear Resistance and Primary and Secondary Relationship. The results show that the critical shear force of undisturbed soil increases with the increase of depth in each forestland. The regression equation of soil shear strength and soil critical shearing force obtained by Coulomb’s formula is: y = 4.372x2 + 29.03 (R2 = 0.813, n = 25). For the same woodland, soil porosity is the main factor affecting the critical shear force in Phyllostachys pubescens forest, soil moisture content in the evergreen broad-leaved forest, while for the other three forest land, soil structure index and soil critical shear force The correlation is the highest; for the critical shear stress of soil and the shear strength of soil, the combined effects of different physical indexes vary. However, in general, the same soil physical indices have basically the same impact on the shear capacity in different forestlands.