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Seasonal Trade-Offs Between Sedimentary Bacterial Generalists and Specialists Sustain Community Stability in Rivers
Shuaishuai Zhang1, Yuxiang Zhu2, Yuanzheng Zhang3
1Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China.
Environmental Microbiology
|July 24, 2026
Summary
Generalists and specialists in river bacteria show distinct seasonal turnover, with generalists crucial for community stability. Their dynamic interplay ensures biodiversity maintenance through ecological state conversion.
Area of Science:
- Ecology
- Microbiology
- Biodiversity Research
Background:
- Understanding how generalist and specialist species coexist is key to maintaining biodiversity.
- Seasonal dynamics of these taxa in river sediments and their role in bacterial community stability are not well understood.
Purpose of the Study:
- To investigate bacterial diversity, assembly processes, and ecological state conversion in river ecosystems.
- To determine the roles of generalists and specialists in maintaining bacterial community stability.
Main Methods:
- 16S rRNA gene amplicon sequencing.
- Statistical analyses including phylogenetic species variability and signal analysis.
- Co-occurrence network analysis to assess community stability.
Main Results:
- Generalists showed higher phylogenetic species variability, while specialists had a stronger phylogenetic signal in ecological preferences.
- Specialists were primarily shaped by stochastic processes, with seasonal variations.
- Generalists played a more significant role in bacterial community stability than specialists, exhibiting higher robustness and lower vulnerability.
Conclusions:
- Ecological state conversion from specialists to generalists is vital for maintaining stable biodiversity.
- Dynamic trade-offs between generalists and specialists are essential for sustaining bacterial community stability in river ecosystems.
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