Balance of Neutral and Deterministic Components in the Dynamics of Activated Sludge Floc Assembly
Balance of Neutral and Deterministic Components in the Dynamics of Activated Sludge Floc Assembly
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DOI：
10.1007/s00248-010-9762-y
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发表时间：
2011-04-01
影响因子：
3.6
通讯作者：
Erijman, Leonardo
中科院分区：
文献类型：
--
作者：
Ayarza, Joaquin M.;Erijman, Leonardo
了解产生群落结构模式的过程是生态研究的中心焦点。有了这个目的，我们操纵的细菌活性污泥的结构，以测试的物种丰富度和组成的细菌群落的活性污泥絮凝体组装在实验室规模的生物反应器的动力学的影响。采用RT-PCR扩增16 SrRNA的变性梯度凝胶电泳分析细菌群落结构。指纹的四个平行的反应器，开始与相同的源社区添加不同的比例，收敛到模式，比预期的机会更相似，这表明在絮凝物的发展确定性选择。中性动力学的证据表明，在源社区中的可用物种的数量上的物种的替代率（细菌类群的时间关系）的依赖。随机动力学的进一步迹象，获得了应用程序的斯隆中性模型的原核生物。拟合的观测数据的模型预测显示，随机成分的重要性增加的水库的物种丰富度的社区是从绘制的大小。两者合计，结果说明了中性和确定性动力学如何在细菌絮凝物的组装中同时运作，并表明两者的平衡取决于源社区的丰富性。
Understanding the processes that generate patterns of community structure is a central focus of ecological research. With that aim, we manipulated the structure of bacterial activated sludge to test the influence of the species richness and composition of bacterial communities on the dynamics of activated sludge floc assembly in lab-scale bioreactors. Bacterial community structure was analyzed using denaturing gradient gel electrophoresis of RT-PCR amplified 16S rRNA. Fingerprinting of four parallel reactors, started with the same source communities added in different proportions, converged to patterns that were more similar than expected by chance, suggesting a deterministic selection in floc development. Evidence for neutral dynamics was suggested by the dependence of the rate of replacement of species (bacterial taxa-time relationships) on the number of available species in the source community. Further indication of stochastic dynamics was obtained by the application of the Sloan neutral model for prokaryotes. The fitting of the observed data to the model predictions revealed that the importance of the stochastic component increased with the size of the reservoir of species richness from which the community is drawn. Taken together, the results illustrate how both neutral and deterministic dynamics operate simultaneously in the assembly of the bacterial floc and show that the balance of the two depends on the richness of the source community.