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Updated: Oct 9, 2025
05:04
Author Spotlight: Understanding Riverine Nitrogen Impacts and Primary Productivity for Effective Nutrient Management
Published on: July 14, 2023
509
Tracking the impacts of nutrient inputs on estuary ecosystem function
Alessandra L Suzzi1, Troy F Gaston1, Louise McKenzie2
1College of Engineering, Science and Environment, University of Newcastle, Ourimbah, NSW, Australia.
The Science of the Total Environment
|December 19, 2021
Summary
Estuaries impacted by sewage can be monitored using microbial communities, which offer a sensitive and informative alternative to traditional methods like benthic macroinvertebrate assessment. This approach reveals nutrient sources and pollution impacts effectively.
Area of Science:
- Environmental science
- Marine biology
- Ecotoxicology
Background:
- Estuaries face significant global impacts from urban and industrial development, leading to concerns about sewage inputs.
- Stable isotope analysis and benthic macroinvertebrate communities are established tools for assessing estuarine health but have limitations.
- Microbial communities in estuaries are understudied for pollution assessment despite their potential as sensitive bioindicators.
Purpose of the Study:
- To investigate the utility of benthic microbial communities as bioindicators in urban estuaries.
- To compare microbial community responses with traditional methods like stable isotope analysis and macroinvertebrate assessments.
- To identify sources of anthropogenic nitrogen pollution in estuarine systems.
Main Methods:
- Stable isotope analysis of seagrass and epiphytes to trace nitrogen sources.
- Assessment of benthic macroinvertebrate community structure and abundance.
- 16S rDNA amplicon sequencing for analyzing benthic microbial community composition and function.
Main Results:
- Stable isotope analysis confirmed treated and untreated sewage as dominant nitrogen sources.
- Benthic macroinvertebrate communities showed shifts in taxa and increased polychaete abundance at impacted sites.
- Microbial communities in sediments provided sensitive and detailed responses to sewage inputs, including shifts in taxa and putative pathogens.
Conclusions:
- Benthic microbial communities are rapid responders to anthropogenic stressors in urban estuaries.
- Microbial community analysis offers a broader and more sensitive assessment of pollution than traditional methods.
- Microbial communities show significant potential as a biomonitoring tool for urban estuarine environments.
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