樟子松人工林树冠内一级枝条空间的分布规律

Modeling of Spatial Distribution of Primary Branches Within the Crowns of Pinus sylvestris Stands

以东北林业大学帽儿山实验林场樟子松人工林为研究对象，采用枝解析的方法，于2002、2003年共测定53株林木（年龄17～38年，直径8．61～21．5cm，树高7．48～18．24cm）的树冠变量，建立树冠内一级枝条个数的预估模型，并对一级枝条在树冠内的垂直分布和水平分布规律进行研究。结果表明：一级枝条个数在树冠有效冠内垂直方向上呈现一“多”一“少”的趋势，在有效冠以下，随着着枝深度的增加，枝条个数呈现直线下降趋势；枝条的水平分布百f以用均匀图形分布讲行很好地拟合．表明圆形分布统计量是分析枝条方位水平分布非常有用的工具。

Models for estimating total number of primary branches and spatial distribution within the live crown were developed in Pinus sylvestris stands in Maoershan experiment farm of Northeast Forestry University. Data of crown attributes were collected from 2002 to 2003 and from 53 sample trees ranging from in age from 17 to 38 a,diameter at breast height（DBH） from 8.61 to 21.5 cm and total height（HT） from 7.48 to 18.24 m. The total number of primary branches in upper part of crown in vertical location show tendency with alternating variation in per whorl, and linear decreasing with the depth into the crown（DINC） in lower part of crown. Analysis of branch azimuths on a whole-tree basis indicated that a uniform distribution was appropriate and a strong positive correlation was found for consecutive whorls of the same number of branches. Overall the models were suitable in dynamic simulating tree crown structure of Pinus sylvestris stands.