ABSTRACT

We attempted to mimic aeolian ecosystems to examine how filters posed by regional characteristics can influence the establishment and growth of airborne microcolonisers of a common air source. Using a natural single source of aerosols we applied a combined microscopy and high-throughput sequencing approach to examine the diversity, settling and growth potential of air-dispersed microbes in water containers representing newly formed aquatic colonisation habitats of different trophic states and salinity. Heterotrophic microeukaryotes were favoured as initial settlers when nutrients were low, while autotrophs rapidly proliferated in the high-nutrient containers, possibly due to favourable germinating conditions for their preferred mode of dispersal with resting spores. Following settling of colonisers, we investigated two contrasting hypotheses: if the different water colonisation habitats harboured the same microbial communities after establishment and growth periods, this would point towards a selection of best-fit cosmopolitan colonisers, regardless of habitat-specific characteristics. Alternatively, community dissimilarities after the growth period would suggest a selection of settlers due to bottom-up controls combined with priority effects. Both analyses suggested that the structure of the microbial communities in the different colonisation habitats were driven by nutrient content and salinity, showing clustering to similar bottom-up forces and dissimilarities in significantly different colonisation habitats.

中文翻译：

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空气传播的水生微生物在不同的淡水定植栖息地中表现出建立和生长的偏好

摘要

我们试图模拟风成生态系统，以研究由区域特征构成的过滤器如何影响共同空气源的空气传播微定殖者的建立和生长。使用天然的单一气溶胶来源，我们应用组合显微镜和高通量测序方法来检查水容器中空气传播微生物的多样性、沉降和生长潜力，这些微生物代表不同营养状态和盐度的新形成的水生定植栖息地。当养分低时，异养微真核生物作为初始定居者受到青睐，而自养生物在高养分容器中迅速增殖，这可能是由于它们首选的休眠孢子散布模式的有利发芽条件。在殖民者定居之后，我们研究了两种截然不同的假设：如果不同的水定殖栖息地在建立和生长期后拥有相同的微生物群落，这将指向最适合的世界性殖民者的选择，而不管栖息地的特定特征如何。或者，由于自下而上的控制和优先效应相结合，生长期后的社区差异表明选择了定居者。两种分析都表明，不同定植栖息地的微生物群落结构受营养成分和盐度的驱动，显示出相似的自下而上的力量和显着不同定植栖息地的差异。这将指向最适合的国际化殖民者的选择，而不管栖息地特定的特征如何。或者，由于自下而上的控制和优先效应相结合，生长期后的社区差异表明选择了定居者。两种分析都表明，不同定植栖息地的微生物群落结构受营养成分和盐度的驱动，显示出相似的自下而上的力量和显着不同定植栖息地的差异。这将指向最适合的国际化殖民者的选择，而不管栖息地特定的特征如何。或者，由于自下而上的控制和优先效应相结合，生长期后的社区差异表明选择了定居者。两种分析都表明，不同定植栖息地的微生物群落结构受营养成分和盐度的驱动，显示出相似的自下而上的力量和显着不同定植栖息地的差异。