【摘要】 利用 17块油松、31块落叶松人工林调查资料 ,根据林分密度与竞争理论 ,构建了一个包含冠幅和冠长的林木竞争指标———冠积指数。研究结果表明 ,冠积指数与直径、树高之间的相关关系存在着基本一致的规律 ,即在直径、树高较小或较矮阶段 ,冠积指数随着直径或树高的增大而增大 ;当直径、树高达到一定值时 ,冠积指数达到最大 ;之后随着直径、树高的增加 ,冠积指数逐渐变小。冠积指数与年龄、立地质量相关性不大。更多还原

【Abstract】 According to the theory of stand density and competition, an index of stand competition——Crown Volume Index (CVI) was constructed based on the investigated data of seventeen Scotch pine plots and thirty-one larch plots of artificial forests. The results showed that there were similarly correlative relationships between CVI and tree diameter, CVI and tree height. CVI tended to increase with the increase of diameter and height when tree diameter and height were small, CVI reached the maximum when diameter and height got to certain values, then CVI tended to decrease with the increase of diameter and height. CVI presented little relationships to tree age and site quality.更多还原