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。
The species component, density and index of crown cover in the tree layer effect on distribution of illumination and under plants in the plant community.
结果表明，沟谷热带雨林各层次中的乔木种群组成是不稳定的，常常随时间而改变。
The result shows that the composition of tree populations is unstable and changes with time.
托克逊地区当时的植被是由银杏、苏铁类和松柏类等乔木，并伴有真蕨类等草本植物组成。
At that time the vegetation of the Toksun area consisted of such arbores as Ginkgo, Cycadopites and Coniferales, associated with herbs such as Filices.
应用推荐