Microbial biodiversity is fundamental to maintain ecosystem functioning in seasonally variable ecosystems. However, it remains unclear how alterations in water availability caused by episodic drying compromise the ability of stream microbes to maintain multiple functions simultaneously (e.g., primary production and carbon cycling). Using data from 32 streams, we investigated how the phenology of annual drying influences stream sediment microbial biodiversity and their capacity to sustain multifunctionality. Our results showed that stream multifunctionality and most bacteria did not respond to changes in drying phenology. Only two bacterial groups, the drying‐resistant Sphingobacteriia and the drying‐sensitive Acidobacteria_Gp7, exhibited positive associations with multifunctionality; whereas, bacterial diversity showed a negative correlation with functions. Among these biodiversity aspects, Sphingobacteriia showed the strongest capacity to maintain multifunctionality at low and moderate performance levels. Our findings will help to better understand the mechanisms through which biodiversity sustains the functioning of seasonally variable streams and their responses to global change.

中文翻译：

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关键细菌群维持流的多功能性以应对间歇性干燥

微生物生物多样性对于维持季节性变化的生态系统中的生态系统功能至关重要。然而，目前尚不清楚间歇性干燥引起的水可用性变化如何损害河流微生物同时维持多种功能（例如初级生产和碳循环）的能力。利用来自 32 条溪流的数据，我们研究了年度干燥物候如何影响溪流沉积物微生物多样性及其维持多功能性的能力。我们的结果表明，流的多功能性和大多数细菌对干燥物候的变化没有反应。只有两个细菌群，即耐干燥的鞘氨醇杆菌和干燥敏感的酸杆菌_Gp7，表现出与多功能性的正相关；而细菌多样性与功能呈负相关。在这些生物多样性方面，鞘氨醇杆菌表现出最强的在低和中等性能水平下维持多功能性的能力。我们的研究结果将有助于更好地了解生物多样性维持季节性变化溪流功能的机制及其对全球变化的反应。