Data for: Key bacterial groups maintain stream multifunctionality in response to episodic drying

Microbial biodiversity is fundamental to maintain ecosystem functioning in
seasonally variable ecosystems. However, it remains unclear how
alterations in water availability caused by seasonal drying compromise the
ability of stream microbes to maintain multiple functions simultaneously
(i.e., multifunctionality). Using data from 32 streams, we investigated
how the phenology of seasonal drying influences stream 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.

微生物生物多样性是维持季节性动态生态系统生态功能的核心基础。然而，目前尚不清楚季节性干旱引发的水分可利用性变化，会如何削弱溪流微生物同时维持多种生态功能（即多功能性（multifunctionality））的能力。本研究依托32条溪流的观测数据，探究了季节性干旱的物候特征如何影响溪流微生物生物多样性及其维持多功能性的能力。研究结果表明，溪流多功能性与绝大多数细菌类群均未对干旱物候的变化产生显著响应。仅有两类细菌类群——抗干旱的鞘脂杆菌纲（Sphingobacteriia）与对干旱敏感的酸杆菌门Gp7类群（Acidobacteria_Gp7）——与多功能性呈显著正相关；而细菌多样性则与生态功能呈负相关。在各类生物多样性组分中，鞘脂杆菌纲在低、中等功能水平下，展现出最强的维持多功能性的能力。本研究结果有助于进一步阐明生物多样性维持季节性动态溪流生态功能的内在机制，以及溪流生态系统对全球变化的响应路径。