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Published on: July 24, 2018
Biome-level biogeography of streambed microbiota
Robert H Findlay1, Christine Yeates, Meredith A J Hullar
1Department of Microbiology, Miami University, Oxford, Ohio 45056, USA. rfindlay@biology.as.ua.edu
Applied and Environmental Microbiology
|April 2, 2008
Summary
Biome type significantly influences stream microbial communities. Bacterial community structure is controlled within biomes, with each biome exhibiting a unique streambed microbial profile.
Area of Science:
- Environmental microbiology
- Ecology
- Biogeochemistry
Background:
- Stream microbial communities are crucial for ecosystem function.
- Understanding factors controlling microbial community structure is essential for ecological assessments.
- Geographic and climatic factors, such as biome type, may influence microbial life in streams.
Purpose of the Study:
- To investigate the influence of biome type on streambed microbial community structure.
- To compare microbial community composition across diverse geographic and climatic regions.
- To determine if biome characteristics control stream microbial diversity and abundance.
Main Methods:
- Field study collecting sediment samples from three distinct biomes: eastern deciduous, southeastern coniferous, and tropical evergreen.
- Analysis of bacterial abundance, microbial biomass (using phospholipid phosphate), and community structure (using phospholipid fatty acid profiles and terminal restriction fragment length polymorphism).
- Application of Principal Component Analysis (PCA) to discern patterns in microbial and bacterial community structures.
Main Results:
- Microbial biomass was significantly higher in the southeastern coniferous biome, correlated with sediment characteristics.
- Principal Component Analysis revealed biome-specific microbial community structures, with distinct separation based on phototrophic microeukaryotes and fungal phospholipid fatty acid abundance.
- Bacterial community structure analysis indicated strong within-biome similarity and unique biome-specific profiles, suggesting biome control.
Conclusions:
- Biome type is a significant factor shaping stream microbial community structure.
- Bacterial communities within streams are strongly influenced by their respective biome characteristics.
- Distinct biomes harbor unique streambed microbial communities, highlighting the importance of geographic and climatic context.
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