Nelder试验:大叶相思树冠生长、多干特征与密度的关系  

Nelder Trial:Effect of Density on Crown Growth and Multi-stem Emergence of Acacia auriculaeformis Forests

作　　者：曾杰[1] 郑海水[1] 翁启杰[1] 黄世能[1] 

机构地区：[1]中国林业科学研究院热带林业研究所,广东广州510520

出　　处：《林业科学研究》1999年第6期577-580,共4页Forest Research

基　　金：加拿大国际发展研究中心(IDRC)资助!(3-P-85-0251)

摘　　要：运用Ｎｅｌｄｅｒ密度试验设计方法，研究了大叶相思林分的树冠生长以及多干现象与密度的关系。结果表明：１年生时各种密度林分均未郁闭，３年生、５年生、７年生时郁闭林分的单株面积上限分别为３．１５ ｍ ２·株－ １、６．２０ ｍ ２·株－ １、７．００ ｍ ２·株－ １。５年生以后，树冠趋于稳定，１～３年生时树冠生长最大的单株面积为５．６４～６．８８ ｍ ２·株－ １，５～７年生时树冠最大的单株面积为１５．５０～１８．６８ ｍ ２·株－ １。林分平均树干数与密度则呈现幂函数关系，林分单株面积小于１ ｍ ２·株－ １时，多干木比例在１０％ 以下；林分密度超过１２．５３ ｍ ２·株－ １以后，多干木比例为１００％ 。By Nelder spacing trial,the density effect of Acacia auriculaeformis forests is discussed.It is shown that all forests with different densities are not closed when one year old.The smallest densities of closed forests are respectively 3.15,6.20 and 7.00 m 2 per tree corresponding to 3,5 and 7 years old.After 5 years old,crown growth tends to stabilize.The largest crown growth emerges in the forests with 5.64～6.88 m 2 per tree occurring in 1～3 years old,while 15.50～18.68 m 2 per tree occurring in 5～7 years old.Mean stem numbers of forests are relative to area per tree in power function.When areas per tree of forests are less than 1.0 m 2,their multi stemmed tree percentages are under 10 percent.While it was 100 percent when forest densities were more than 12.53 m 2 per tree.

关 键 词：Nelder密度试验 初始密度 大叶相思树 树冠竞争 

分 类 号：S792.99[农业科学—林木遗传育种]