毛竹林空间结构与更替动态的关系

以浙江天目山国家级自然保护区内的毛竹Phyllostachys edulis林为研究对象，根据2010，2012和2014年各大年毛竹林标准地数据，选择最近邻竹株数、角尺度、大小比和竞争指数等4个空间结构指数做主成分分析，分析毛竹林空间结构与更替动态的关系。结果表明:各空间结构因子对新竹生长影响重要性排序为最近邻竹株数>大小比数>竞争指数>角尺度，对毛竹死亡影响重要性排序为最近邻竹株数>大小比数>竞争指数>角尺度；新竹更容易在最近邻竹株数 < 4株或最近邻竹株数>7株的区域内发笋生长，老竹更容易在最近邻竹株数>7株的区域死亡；毛竹活竹、新竹和死竹均呈现聚集分布，三者在角尺度上无显著差异（P>0.05）；毛竹林整体处于中庸状态，新竹主要处于亚优势状态，而死竹主要处于劣势状态，三者在大小比数上存在极显著差异（P < 0.01）；就平均竞争指数而言，死竹平均竞争指数最大，新竹最小。说明竹子生长状况对毛竹更替有重要影响。

Relationship of spatial structure and regeneration dynamics in Phyllostachys edulis

To determine the relationship between spatial structure and regeneration dynamics of a Phyllostachys edulis stand, an experiment was conducted in Mount Tianmu National Nature Reserve of Zhejiang Province. Data was taken from Ph. edulis stand in 2010, 2012, 2014. Fourur spatial structural indices, namely, nearest bamboo number, uniform angle, neighborhood comparison, and competition index, were selected to describe spatial structural characteristics of the bamboo. A principal component analysis was used for analysis. Results indicated an order of importance for spatial structural indices affecting Ph. edulis growth as nearest bamboo number > neighborhood comparison > competition index > uniform angle, and an order concerning importance of spatial structural indices affecting Ph. edulis death as nearest bamboo number > competition index > neighborhood comparison > uniform angle. New bamboo was apt to grow in an area where the nearest bamboo number was < 4 or > 7; whereas, old bamboo was apt to die if the nearest bamboo number was > 7. Living bamboo, new bamboo, and dead bamboo all presented a clustered distribution pattern with no significant differences at the uniform angles (P>0.05). Living bamboo had an intermediate status with new bamboo in a sub-dominant state and dead bamboo in a relatively disadvantageous state. All showed highly significant differences in neighborhood comparison (P < 0.01). An intensity of average competition index as dead bamboo > living bamboo > new bamboo. This indicated that the growth condition had an important effect on bamboo regeneration.