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Updated: Jun 23, 2026
22:38
Chemotactic Response of Marine Micro-Organisms to Micro-Scale Nutrient Layers
Published on: May 28, 2007
Salt marsh sediment bacteria: their distribution and response to external nutrient inputs
Jennifer L Bowen1, Byron C Crump, Linda A Deegan
1Marine Biological Laboratory, The Ecosystems Center, Woods Hole, MA, USA. jlbowen@princeton.edu
The ISME Journal
|May 8, 2009
Summary
Human disturbance impacts salt marsh sediment bacteria, but local habitat factors, not broad-scale conditions, primarily shape bacterial communities. Nutrient enrichment had minimal effects, except in algae-rich areas.
Area of Science:
- Microbial Ecology
- Environmental Science
- Ecology
Background:
- Understanding microbial distribution and community composition is crucial.
- Less is known about how environmental disturbance affects these bacterial communities.
- Salt marshes are vital ecosystems sensitive to disturbance.
Purpose of the Study:
- To determine the effects of human disturbance on salt marsh sediment bacterial distribution and community structure.
- To investigate the roles of intrinsic and extrinsic factors in structuring these communities.
- To assess the impact of nutrient enrichment on bacterial diversity.
Main Methods:
- Utilized denaturing gradient gel electrophoresis (DGGE) of 16S rRNA.
- Analyzed bacterial communities in five habitats across four salt marshes in Massachusetts.
- Experimentally enriched two marshes with nitrogen and phosphorus fertilizers.
Main Results:
- Broad-scale extrinsic factors did not significantly influence bacterial distribution.
- Local-scale environmental heterogeneity (intrinsic factors) played a key role.
- Nutrient enrichment had limited impact, except in filamentous algae-rich habitats.
- Significant convergence in microbial community composition was observed across similar habitats.
Conclusions:
- Habitat-specific intrinsic factors are primary drivers of microbial diversity in salt marsh sediments.
- Local environmental conditions are more influential than broad-scale factors.
- Nutrient enrichment effects are habitat-dependent and generally minor.
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