不同林龄桉树人工林森林空间结构差异研究

采用空间代替时间的方法，对不同林龄桉树人工林的空间结构进行了比较研究。结果表明：不同生长阶段桉树人工林空间结构之间存在着差异。，桉树人工林1-年生增长迅速，呈对数增长；随林龄增加．郁闭度、枯枝落叶（厚度和覆盖率）表现为先增加后减少趋势。桉树人工林层次结构分明，各层优势植物种类基本相同，但不同林龄阶段，各层数量和分布广度（植株大小高矮、植物种类数量和覆盖率）有随林龄增加基本表现为“大-小-大”的趋势。聚类分析表明，林龄之间空间结构差异明显。

Study on Differences in Spatial Structure of Forest Between Different Forest Age of Eucalyptus Plantations

Spatial structure of forest between different forest age of Eucalyptus plantations were compared by the method of spatial instead of time.the results were showed as followed:there great differences between different Eucalyptus plantations.The growth speed of plantations were very rapid in the 15 year old,and were presented by logarithm growth.With the increase of forest age canopy density and litter(including litter thickness and litter cover percentage) of the plantations both increased and then decreased.Hiberarchy of different forest age of Eucalyptus plantations were clear,their dominant plant were all nearly identical,however the quantity and distributing span(individual size,number,species number) of undergrowth plants in different constituent layers were changed from increase and decrease to increase as forest age of plantations as was increased.It was also showed that spatial structure of different forest age plantations could significantly differentiated by cluster analysis.