郁闭林分中,各树冠的外部形态与内部结构,通常比较接近.它们的外形,近似一单回旋体的表面,但下部因相邻树冠挤压而有一定的变形(藤大六郎,1979).其内部结构,由里向外可划分为两部分:一部分无叶,叫轴心区;一部分载叶,叫覆盖区.自上而下又可将载叶覆盖区分为三层:一是受光树冠;一是都闭树冠;一是庇阴树冠(Assmann,1962). In candelabrum, the external shape and internal structure of each canopy are usually similar, and their shape approximates the surface of a single loft, but the lower part has some deformation due to the extrusion of the adjacent canopy (Tadakura, 1979 ). Its internal structure, from the inside out can be divided into two parts: a part of no leaves, called the axis area; part of the carrier leaves, called the coverage area. Top down can be divided into three leaf carrier coverage: First Light crown; one is closed canopy; one is the shade of the crown (Assmann, 1962).