基于防御性状对热带森林树种空间分布格局的解释

Interpretation of the Spatial Distribution Patterns of Tropical Forest Tree Species Based on Defensive Traits

探究影响群落物种分布和共存的主要因素是群落生态学研究的重要目标。热带森林中局域尺度上的物种多样性可能是由于负密度制约机制的影响。密度制约对树种的空间分布格局会产生负影响,为了抵抗这种负效应,树种可能在防御特征上表现出一定的分化。通过对西双版纳热带森林20种不同空间分布树种(10种非聚集型树种和10种聚集型树种)的物理防御和化学防御性状进行比较,探讨了防御性状对森林优势树种空间分布格局的解释。结果表明:聚集树种和非聚集树种的防御性状具有显著性的差异;聚集树种比非聚集树种具有更高的化学多样性;但是,与非聚集树种相比,聚集树种并没有观察到更强的物理防御。进一步研究表明,化学防御机制可能是解释西双版纳热带森林树种空间分布格局的一个重要策略。

Exploring the main factors affecting the distribution and coexistence of community species is a major goal of community ecology research.Species diversity at the local scale in tropical forests may be due to the influence of negative density dependence mechanisms.Negative density dependence affects the spatial distribution patterns of tree species.In order to resist this negative effect,tree species may show some differentiation in defense characteristics.In this study,the defense traits of 20 spatially distributed tree species(10 non-aggregating and 10 aggregating species)in Xishuangbanna tropical forests are compared to explore the interpretation of defense traits on the spatial distribution patterns of dominant tree species in the forest.It was shown that defense traits of aggregated and non-aggregated tree species were significantly different;aggregated species had higher chemical diversity than non-aggregated species;however,stronger physical defense was not observed for aggregated species compared to non-aggregated species.Our study suggests that chemical defense mechanisms may be an important strategy to explain the spatial distribution patterns of tree species in Xishuangbanna tropical forests.