Luo Fang, Meng Ling-Zeng, Wang Jian, Liu Yan-Hong
Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, Yunnan, China.
College of Biological and Agricultural Sciences, Honghe University, Mengzi, 661199, Yunnan, China.
Front Zool. 2022 Mar 4;19(1):10. doi: 10.1186/s12983-022-00455-y.
Separation of biotic and abiotic impacts on species diversity distribution patterns across a significant climatic gradient is a challenge in the study of diversity maintenance mechanisms. The basic task is to reconcile scale-dependent effects of abiotic and biotic processes on species distribution models. Here, we used a hierarchical modeling method to detect the host specificities of bark beetles (Scolytinae and Platypodinae) with their dependent tree communities across a steep climatic gradient, which was embedded within a relatively homogenous spatial niche.
Species turnover of both trees and bark beetles have an opposite pattern along the climatic proxy (represented by the elevation gradients) at the regional scale, but not at local spatial scales. This pattern confirmed the hypothesis wherein emphasis was on influences of macro-climate on local biotic interactions between trees and hosted bark beetle communities, whereas local biotic relations, represented by host specificity dependence, were regionally conserved.
At a confined spatial scale, cross-taxa comparisons of β-diversity highlighted the importance of simultaneous impacts from both extrinsic factors related to geography and environment, and intrinsic factors related to organism characteristics. The effects of tree abundance and phylogeny diversity on bark beetle diversity were, to a large extent, indirect, operating via changes in bark beetle abundance through spatial and temporal dynamics of resources distribution. Tree host dependence, which was considered and represented by host specificities, plays a minor role on the hosted beetle community in this concealed wood decomposing interacting system.
在多样性维持机制研究中，区分生物和非生物因素对跨越显著气候梯度的物种多样性分布模式的影响是一项挑战。基本任务是协调非生物和生物过程对物种分布模型的尺度依赖性影响。在此，我们使用一种层次建模方法，在一个相对同质的空间生态位内，检测树皮甲虫（小蠹亚科和长小蠹亚科）与其依赖的树木群落跨越陡峭气候梯度的寄主特异性。
在区域尺度上，树木和树皮甲虫的物种周转率沿气候指标（以海拔梯度表示）呈现相反模式，但在局部空间尺度上并非如此。这种模式证实了如下假设：宏观气候对树木与寄主树皮甲虫群落之间的局部生物相互作用有影响，而以寄主特异性依赖为代表的局部生物关系在区域上是保守的。
在有限的空间尺度上，β多样性的跨类群比较突出了与地理和环境相关的外在因素以及与生物体特征相关的内在因素同时产生影响的重要性。树木丰度和系统发育多样性对树皮甲虫多样性的影响在很大程度上是间接的，通过资源分布的时空动态变化引起树皮甲虫丰度的改变来发挥作用。在这个隐蔽的木材分解相互作用系统中，由寄主特异性所考虑和代表的树木寄主依赖性，对寄主甲虫群落的作用较小。
