迎春5号杨生长评价与经营密度

Evaluation of Growth and Management Density for Yingchun Poplar 5

迎春５号杨是牡丹江林区１９８２年从中国林科院引进的黑小杨混合系中选育出的优良无性系。该品种具有生长迅速、材质优良、抗性强等优良特性。１５年生林分平均胸径达３０１ｃｍ、平均树高达２０１ｍ、单株材积０５１４９ｍ３，显著超过了小黑杨等参试品种。根据树冠面积与胸径相关关系选择数学模型进行拟合，得到ｙ＝ａ＋ｂｘ＋ｃｘ２＋ｄｘ３为最佳模型，以此编制迎春５号杨经营密度表。

Yingchun poplar 5 is a fine clone cultivated from mixed strains of Heixiao poplar introduced from the Chinese Academy of Forestry in Mudanjiang Forestry Area in 1982. This strain is of several fine characters such as fast-growing, fine wood quality and high resistance etc. The mean breast-height diameter, mean tree height and individual volume of 15-year-old stands are 30.1 cm, 20.1 m and 0.514 9 m 3 respectively, exceeding that of Lesser Black poplar significantly. According to the correlation relationship between crown area and breast-height diameter, the most suitable mathematical model was obtained: y=a+bx+cx 2 +dx 3 , with which management density table of Yingchun poplar 5 was made.