Li Hua, Huo Da, Wang Weibo, Chen Youxin, Cheng Xiaoli, Yu Gongliang, Li Renhui
CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.
Academy of Plateau Science and Sustainability, Qinghai Normal University, Xining, China.
Mol Ecol. 2020 Apr;29(8):1560-1573. doi: 10.1111/mec.15424. Epub 2020 Apr 21.
The potential of biodiversity loss to impair the delivery of ecosystem services has motived ecologists to better understand the relationship between biodiversity and ecosystem functioning. Although increasing evidence underlines the collective contribution of different biodiversity components on the simultaneous performance of multiple functions (multifunctionality), we know little about the trade-offs between individual diversity effects and the extent to which they determine multifunctionality differentially. Here, at a subcontinental scale of 62 dryland sites, we show in phototrophic microbiota of biological soil crusts (biocrusts) that, whereas richness alone is unable to guarantee the maxima of multifunctional performance, interspecies facilitation and compositional identity are particularly stronger but often neglected predictors. The inconsistent effects of different biodiversity components imply that soil multifunctionality can be lost despite certain species remaining present. Moreover, we reveal a significant empirical association between species functional importance and its topological feature in co-occurrence networks, indicating a functional signal of species interaction. Nevertheless, abundant species tend to isolate and merely interact within small topological structures, but rare species were tightly connected in complicated network modules. Our findings suggest that abundant and rare species of soil phototrophs exhibit distinct functional relevance. These results give a comprehensive view of how soil constructive species drive multifunctionality in biocrusts and ultimately promote a deeper understanding of the consequences of biodiversity loss in real-world ecosystems.
生物多样性丧失影响生态系统服务功能的可能性，促使生态学家更好地理解生物多样性与生态系统功能之间的关系。尽管越来越多的证据强调了不同生物多样性组成部分对多种功能（多功能性）同时发挥作用的集体贡献，但我们对个体多样性效应之间的权衡以及它们在多大程度上差异化地决定多功能性知之甚少。在这里，在一个包含62个旱地站点的次大陆尺度上，我们在生物土壤结皮（生物结皮）的光合微生物群落中发现，仅物种丰富度并不能保证多功能性能达到最大值，种间促进作用和组成特性是特别重要但常被忽视的预测指标。不同生物多样性组成部分的影响不一致，这意味着尽管某些物种仍然存在，土壤多功能性仍可能丧失。此外，我们揭示了物种功能重要性与其在共存网络中的拓扑特征之间存在显著的实证关联，表明了物种相互作用的功能信号。然而，优势物种倾向于孤立存在，仅在小的拓扑结构内相互作用，而稀有物种则在复杂的网络模块中紧密相连。我们的研究结果表明，土壤光合生物中的优势物种和稀有物种表现出不同的功能相关性。这些结果全面地展示了土壤建设性物种如何驱动生物结皮中的多功能性，并最终促进对现实世界生态系统中生物多样性丧失后果的更深入理解。
