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以长白山地区 2 6a生长白落叶松人工林为研究对象 ,采用枝解析的方法 ,测定了 2 5株林木 (直径 10 5～2 4 9cm)的树冠变量 ,并建立了预测树冠外侧形状的冠形模型。基于枝条着枝深度 (DINC)和林木变量所建立的树冠形状模型包括 :基径、枝长、着枝角度和弦长等预估模型。对于大小相同树木的主要枝条来讲 ,这些树冠变量是随着DINC的增加而增大 ;而林木的胸径 (DBH)和树高 (HT)变量很好地反映了不同大小树木的冠形变化。冠形预测模型预测效果良好 ,充分体现了树冠结构的变化趋势 :树冠形状在树冠的中上部呈抛物线体 ,而在树冠的下部则为近圆柱体。文中所建模型 ,可以合理地描述长白落叶松人工林的树冠形状及其变化规律。
Taking the growth of Larix olgensis plantation in Changbai Mountain area as the research object, the crown variables of twenty-five tree species (diameter from 105 to 2949 cm) were determined by the method of branch analysis, and the crown shape of crown model. Canopy shape models based on branch stick depths (DINC) and tree variables include predictive models such as base diameter, branch length, branch angle and chord length. For the main branches of the same size, the crown variables increased with the increase of DINC, while the DBH and HT variables of the trees reflected the crown changes of different size trees. The forecasting effect of the crown prediction model is good, which fully reflects the change trend of the crown structure: the shape of the crown is a parabola in the middle and upper part of the canopy, and the near cylinder in the lower part of the crown. The model built in this article can describe the crown shape and its variation law of Larix olgensis plantations reasonably.