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Bacterioplankton Dynamics within a Large Anthropogenically Impacted Urban Estuary
Thomas C Jeffries1, Maria L Schmitz Fontes2, Daniel P Harrison3
1Plant Functional Biology and Climate Change Cluster, University of Technology SydneySydney, NSW, Australia; Hawkesbury Institute for the Environment, Western Sydney UniversityPenrith, NSW, Australia.
Frontiers in Microbiology
|February 10, 2016
Summary
Microbial communities in urban estuaries like Sydney Harbor shift with nutrient levels and rainfall. These changes impact aquatic health and ecosystem functions, revealing dynamic responses to environmental pressures.
Area of Science:
- Microbial ecology
- Aquatic microbiology
- Environmental science
Background:
- Microorganisms are key indicators of aquatic health, influencing ecosystem services and causing issues like harmful blooms.
- Urbanized estuaries face significant environmental pressures, making them ideal for studying anthropogenic impacts on microbial communities.
Purpose of the Study:
- To investigate shifts in microbial community composition and function in Sydney Harbor.
- To understand the influence of natural and anthropogenic physicochemical gradients on microbial ecology.
Main Methods:
- Utilized amplicon sequencing of the 16S rRNA gene.
- Employed shotgun metagenomics for comprehensive analysis.
- Studied microbial communities across natural and anthropogenic gradients during high and low rainfall periods.
Main Results:
- Observed strong microbial biogeography patterns driven by nutrient concentration and dissolved oxygen.
- Identified partitioning of microbial communities based on nutrient regimes and rainfall.
- Detected shifts in specific bacterial families (e.g., Rhodobacteraceae, Flavobacteriaceae) and enrichment of metabolic pathways (e.g., nutrient metabolism, hydrocarbon degradation).
- Found community beta-diversity varied between sampling periods, indicating temporal dynamics.
Conclusions:
- Nutrient concentration and dissolved oxygen are key drivers of microbial community structure and function in urban estuaries.
- Anthropogenic inputs significantly influence microbial ecology, leading to distinct community compositions and metabolic potentials.
- The study highlights the dynamic nature of microbial communities in response to environmental changes and anthropogenic pressures.
Keywords:
anthropogenic impactsenvironmental microbiologyenvironmental pollutantsestuarine ecologyeutrophicationmetagenomicsmicrobial ecologymicrobiomeMore Related Videos
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