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A Lipid Extraction and Analysis Method for Characterizing Soil Microbes in Experiments with Many Samples
Published on: July 16, 2017
Microbial community shifts influence patterns in tropical forest nitrogen fixation.
Sasha C Reed1, Alan R Townsend, Cory C Cleveland
1US Geological Survey, Southwest Biological Science Center, Moab, UT 84532, USA. screed@usgs.gov
Oecologia
|May 11, 2010
Summary
Microbial biodiversity significantly impacts ecosystem processes. In tropical rainforests, nitrogen fixation hotspots showed higher diversity and unique microbial communities, suggesting structure influences function.
Area of Science:
- Tropical rainforest ecology
- Microbial ecology
- Biogeochemistry
Background:
- Biodiversity's role in ecosystem function is well-studied, but microbial community structure-ecosystem process links remain unclear.
- Nitrogen (N) fixation is a critical ecosystem process, particularly in nutrient-limited environments like tropical rainforests.
Purpose of the Study:
- To investigate the relationship between free-living N-fixer community structure and N fixation rates in tropical rainforest leaf litter.
- To determine the impact of phosphorus (P) fertilization on N-fixer communities and N fixation.
Main Methods:
- Utilized tropical rainforest fertilization plots to compare N-fixer community composition, diversity, and abundance with in situ N fixation rates.
- Analyzed N fixation 'hotspots' and their associated microbial communities in control and P-fertilized plots.
Main Results:
- N fixation rates varied significantly, with 'hotspots' exhibiting distinct N-fixer compositions and higher diversity compared to average zones.
- Phosphorus fertilization enhanced N fixation efficiency and rates, increased N-fixer abundance, and altered community diversity by eliminating a novel group.
- Complex relationships between microbial diversity and N fixation function were observed, highlighting community dynamism.
Conclusions:
- The tropical rainforest litter layer supports high N fixation rates and unique N-fixing organisms.
- Structural shifts in N-fixing communities can significantly influence system-scale N fixation rates, mirroring patterns seen in plant ecology.
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