The competition occurs widespreadly among the major componentspecies of Karst vegetation in the middle area of Guizhou , but the intensity of competition vary among the species.
黔中喀斯特植被的主要组成树种间普遍存在着竞争关系．但不同树种间竞争强度有所差异。
2
The speciescomponent, density and index of crown cover in the tree layer effect on distribution of illumination and under plants in the plant community.
群落中光照的分布状况受乔木层的种类组成、密度与冠幅指数等因子的影响，且对下层植物分布有较大的作用。
3
The species of aloe, its chemical component and efficacy were reviewed.