Data from: Diversity partitioning confirms the importance of beta components in tropical rainforest Lepidoptera

Tropical beta diversity, and particularly that of herbivorous insects in rainforests, is often considered enormous, but this notion has recently been challenged. As tropical beta diversity is highly relevant to our view on biodiversity, it is important to gain more insights and resolve methodological problems that may lead to the contradictions in different studies. We used data on two ecologically distinct moth families from Southeast-Asia and analyzed separately the contribution of beta components to overall species richness at three spatial scales. Observed diversity partitions were compared under different types of null models. We found that alpha diversity was lower than expected from null models, whereas hierarchical beta components were larger than expected. Beta components played a significant role in shaping gamma diversity, and their contribution can be high (multiplicative beta >5). We found a reduction of beta components when comparing primary forests and agricultural sites (cf. “biotic homogenization”), but even in these habitats beta components were still substantial. Our analyses show that beta components do play an important role in our data on tropical herbivorous insects, and that these results are not due to lumping different habitats when sampling environmental gradients.

热带地区的β多样性（beta diversity），尤其是热带雨林中的植食性昆虫β多样性，常被认为极为丰富，但这一观点近期受到了挑战。鉴于热带β多样性与我们对生物多样性的认知高度相关，因此获取更多相关见解并解决可能导致不同研究结论矛盾的方法论问题，具有重要意义。我们采用了来自东南亚的两个生态特征迥异的蛾类科的调查数据，分别分析了三种空间尺度下β组分对总物种丰富度的贡献。我们基于不同类型的零模型（null model）对观测到的多样性分区结果进行了对比。研究发现，α多样性（alpha diversity）低于零模型的预期值，而层级式β组分则高于预期水平。β组分在塑造γ多样性（gamma diversity）中发挥了重要作用，其贡献比例可高达较高水平（乘性β多样性>5）。对比原始森林与农业用地时，我们发现β组分有所降低（可参考“生物均质化（biotic homogenization）”概念），但即便在这些生境中，β组分依然占据可观比例。我们的分析表明，β组分在本次热带植食性昆虫相关研究数据中确实发挥了关键作用，且该结果并非因在环境梯度采样过程中合并不同生境所导致。