南方林区马尾松不同套种模式群落高度级结构分析

以高度级为参考坐标,应用衡量群落结构及其动态的失稳率和群落垂直空间的分享度等指标对南方林区4个不同套种模式马尾松群落高度级结构特征及其动态进行分析.结果表明:套种模式1、套种模式2和套种模式4群落高度级内个体数量分布呈先降低后升高的U型结构,物种数量和物种个体数量在中等高度级出现低频区域,群落动态表现为高等高度级衰退趋势;套种模式3群落呈基部大、顶层小的塔形结构,物种数量和物种个体数量主要集中在低等高度级,反映出该群落具有极强的增长特性.不同套种模式群落分享度均比较低,反映出南方林区马尾松人工林群落物种数量相对单一的弊端.

Highness Class Structure of Pinus massoniana Forest with Different Intercropping Modes in Southern Forest

The highness class structure of Pinus massoniana forest with different intercropping modes in southern forest was measured and analyzed. When the community of highness class was regarded as coordinate axis, a series of targets, e. g. lost stable rate of individual number between highness classes and dynamics of the community. The results indicated that the individual number and species number of the community first reduced then decreased as U-type structure with highness classes raised in intercropping modes 1,2 and 4. Low-frequency region was in medium height class, showed that community dynamics declining trend in higher class. The individual number and species number of the community in intercropping modes 3 mainly concentrated in low height level as a pyramid structure, reflect those communities has a very strong growth characteristics. Species sharing degree were lower in different intercropping modes community, which reflected a malpractice that number of species is relatively simple in Pinus massoniana plantation community in Southern forest.