Laboratoire Microorganismes: Génome et Environnement, Clermont Université, Université Blaise Pascal, Clermont-Ferrand, France.
FEMS Microbiol Ecol. 2013 Jul;85(1):85-94. doi: 10.1111/1574-6941.12100. Epub 2013 Mar 18.
Understanding the spatial distribution of aquatic microbial diversity and the underlying mechanisms causing differences in community composition is a challenging and central goal for ecologists. Recent insights into protistan diversity and ecology are increasing the debate over their spatial distribution. In this study, we investigate the importance of spatial and environmental factors in shaping the small protists community structure in lakes. We analyzed small protists community composition (beta-diversity) and richness (alpha-diversity) at regional scale by different molecular methods targeting the gene coding for 18S rRNA gene (T-RFLP and 454 pyrosequencing). Our results show a distance-decay pattern for rare and dominant taxa and the spatial distribution of the latter followed the prediction of the island biogeography theory. Furthermore, geographic distances between lakes seem to be the main force shaping the protists community composition in the lakes studied here. Finally, the spatial distribution of protists was discussed at the global scale (11 worldwide distributed lakes) by comparing these results with those present in the public database. UniFrac analysis showed 18S rRNA gene OTUs compositions significantly different among most of lakes, and this difference does not seem to be related to the trophic status.
了解水生微生物多样性的空间分布以及导致群落组成差异的潜在机制，是生态学家面临的一项具有挑战性和核心的目标。最近对原生生物多样性和生态学的深入了解，增加了人们对其空间分布的争论。在这项研究中，我们调查了空间和环境因素对湖泊中小型原生生物群落结构的重要性。我们通过针对 18S rRNA 基因（T-RFLP 和 454 焦磷酸测序）的不同分子方法，在区域尺度上分析了小型原生生物群落的组成（β多样性）和丰富度（α多样性）。我们的结果表明，稀有和优势分类群的距离衰减模式，以及后者的空间分布遵循岛屿生物地理学理论的预测。此外，湖泊之间的地理距离似乎是塑造研究湖泊中原生生物群落组成的主要力量。最后，通过将这些结果与公共数据库中的结果进行比较，在全球尺度（11 个分布在世界各地的湖泊）上讨论了原生生物的空间分布。UniFrac 分析表明，大多数湖泊中的 18S rRNA 基因 OTUs 组成存在显著差异，而且这种差异似乎与营养状态无关。
