西双版纳热带森林空心树形成概率及其影响因素

Likelihood and influencing factors of tree cavities in tropical forest in Xishuangbanna,Southwest China

空心树是森林生态系统的重要结构组分,它在维持森林动物群落的物种多样性方面起着重要作用。选取西双版纳20 hm^2热带森林动态监测样地为研究对象,采用地面观测法调查了样地内所有胸径≥5 cm的活体乔木,研究热带森林主要空心树形成概率及其影响因素。运用逻辑斯蒂回归模型探讨空心树形成概率与胸径的关系;再结合地形数据,拟合空心树形成概率的最优模型。结果表明:该样地森林的空心树形成概率与物种有关,空心树形成概率最高的4个种分别是红锥(Castanopsis hystrix)(21.23%)、黑毛柿(Diospyros hasseltii)(13.53%)、毛猴欢喜(Sloanea tomentosa)(12.06%)和短刺锥(C.echidnocarpa)(11.99%);空心树形成概率随着树木胸径的增加而增加,相同径阶下各树种空心树形成概率不同;根据拟合的最优模型,空心树形成概率主要受胸径、坡度、坡向的影响。这些结果表明,空心树形成概率不仅与树木本身的生长有关,还受到地形因子的影响。提出对热带森林多样性的保护与管理的建议。

Hollow-bearing trees （HBT） are important components in forest ecosystems, playing a crucial role in maintaining animal diversity. To quantify the probability and influencing factors of tree cavities in tropical forests, we conducted a ground-based observation in a 20-hm2 tropical for- est community in Xishuangbanna, Southwest China. We used Logistic models to study the rela- tionship between the probability of tree cavities and the diameter at breast height （DBH）. The re- sults showed that the probability of tree cavities was positively related with DBH, and varied across different tree species. The four species with the highest probability of tree cavities were Castanopsis hystrix （ 21.23% ） , Diospyros hasseltii （ 13.53% ） , Sloanea tomentosa （ 12.06% ） and C. echidnocarpa （11.99%）. In an optimal fitting model, tree cavities were strongly correlated with DBH, slope and aspect of the tree location. Our results indicate that tree cavities are related with tree traits and topographic factors, and therefore have implication for the conservation and management of biodiversity in tropical forests.