Divergent assemblage patterns and driving forces for bacterial and fungal communities along a glacier forefield chronosequence
Divergent assemblage patterns and driving forces for bacterial and fungal communities along a glacier forefield chronosequence
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沿着冰川前场时间序列的细菌和真菌群落的不同组合模式和驱动力
DOI：
10.1016/j.soilbio.2017.12.019
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发表时间：
2018-03-01
影响因子：
9.7
通讯作者：
Li, Chunyang
中科院分区：
文献类型：
--
作者：
Jiang, Yonglei;Lei, Yanbao;Li, Chunyang
尽管微生物在新近冰消区的土壤发生和生态系统发育中具有普遍的分布和重要的生态功能，但细菌和真菌之间存在着截然不同的演替轨迹，但群落组装的驱动力仍然没有得到很好的解决。在这项研究中，我们分析了与海螺沟冰川时序中的7个不同阶段相关的细菌和真菌谱系，以量化其分类组成和演替动态，并破译自下而上控制土壤养分和植被改变以及自上而下的压力线虫食草动物的相对贡献。共生网络表明，细菌和真菌的群落复杂性通常在中间时序阶段达到峰值。细菌中的重叠节主要属于变形菌门和酸杆菌门，真菌中的重叠节主要属于子囊菌门和担子菌门，指示种分析进一步支持了这一结论。在分区和结构方程模型的变化表明，土壤特性的主要代理塑造微生物群落结构，特别是在早期阶段。生物因素的重要性，包括植物丰富度和线虫喂养，增加在最后两个阶段沿着随着针叶林的建立，最终管理的营业额的真菌群落。此外，细菌群落在组装过程中表现出更紧凑的网络拓扑结构，从而支持决定论，而真菌群落的松散聚类表明它们更多地由随机过程决定。这些证据共同揭示了不同的演替轨迹和驱动力土壤细菌和真菌群落沿着冰川前田时序。
Despite the ubiquitous distributions and critical ecological functions of microorganisms in pedogenesis and ecosystem development in recently deglaciated areas, there are contrasting successional trajectories among bacteria and fungi, but the driving forces of community assembly still remain poorly resolved. In this study, we analyzed both bacterial and fungal lineages associated with seven different stages in the Hailuogou Glacier Chronosequence, to quantify their taxonomic composition and successional dynamics, and to decipher the relative contribution from the bottom-up control of soil nutrients and altered vegetation as well as top-down pressures from nematode grazers. Co-occurrence networks showed that the community complexity for both bacteria and fungi typically peaked at the middle chronosequence stages. The overlapping nodes mainly belonged to Proteobacteria and Acidobacteria in bacteria, and Ascomycota and Basidiomycota in fungi, which was further supported by the indicator species analysis. Variation in partitioning and structural equation modeling suggested that edaphic properties were the primary agents shaping microbial community structures, especially at the early stages. The importance of biotic factors, including plant richness and nematode feeding, increased during the last two stages along with the establishment of a coniferous forest, eventually governing the turnover of fungal communities. Moreover, bacterial communities exhibited a more compact network topology during assembly, thus supporting determinism, whereas the looser clustering of fungal communities illustrated that they were determined more by stochastic processes. These pieces of evidence collectively reveal divergent successional trajectories and driving forces for soil bacterial and fungal communities along a glacier forefield chronosequence.