Sediment Bacteria in the Alpine Lake Sayram: Vertical Patterns in Community Composition
Keqiang Shao1, Boqiang Qin1, Jianying Chao2
1State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
Microorganisms
|November 25, 2023
Summary
This study investigated alpine lake sediment bacteria, revealing depth-related diversity patterns and dominant nitrate-reducing genera like Acinetobacter. Carbonate and organic carbon influenced bacterial community composition in Lake Sayram sediments.
Area of Science:
- Microbial Ecology
- Limnology
- Environmental Science
Background:
- Alpine lake bacterial communities are crucial for understanding ecosystem responses to climate change.
- Limited research exists on the vertical distribution of bacterial communities within alpine lake sediments.
- Lake Sayram, China's largest alpine lake, presents a unique system for studying these patterns.
Purpose of the Study:
- To investigate the vertical patterns of bacterial populations and community structure in the sediment core of Lake Sayram.
- To identify dominant bacterial phyla and genera and their distribution with sediment depth.
- To explore the environmental factors influencing the vertical variations in bacterial community composition.
Main Methods:
- Collection of a 100 cm sediment core from Lake Sayram.
- 16S rRNA gene-targeted amplicon sequencing to analyze bacterial populations.
- Shannon diversity index calculation and Canonical Correspondence Analysis (CCA) for community structure and environmental factors.
Main Results:
- Bacterial diversity peaked at the sediment surface and showed a complex pattern with depth.
- Proteobacteria, Firmicutes, and Planctomycetes were the most abundant phyla; Acinetobacter, Hydrogenophaga, and Pseudomonas were dominant genera.
- Relative abundance of Acinetobacter increased with depth, while Hydrogenophaga and Pseudomonas decreased; carbonate and total organic carbon (TOC) correlated with bacterial community composition (BCC).
Conclusions:
- Nitrate-reducing bacteria, including Acinetobacter, Hydrogenophaga, and Pseudomonas, are likely prevalent in Lake Sayram sediments.
- Vertical patterns of bacterial communities in alpine lake sediments are significantly influenced by environmental factors like carbonate and TOC.
- This study enhances understanding of bacterial communities in alpine lake sediments, particularly in arid and semi-arid regions.
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