Distinctive species interaction patterns under high nitrite stress shape inefficient denitrifying phosphorus removal
Xue Wang1, Guoyu Zhang2, Aizhong Ding1
1College of Water Sciences, Beijing Normal University, Beijing 100875, China.
Bioresource Technology
|December 28, 2023
Summary
Denitrifying phosphorus removal with nitrite is efficient but can be inhibited. High nitrite stress shifts microbial communities, impacting phosphorus removal stability and performance.
Area of Science:
- Environmental Microbiology
- Water Treatment Technologies
- Biogeochemical Cycles
Background:
- Denitrifying phosphorus removal (DPR) using nitrite as an electron acceptor offers a resource-efficient method for simultaneous nitrogen and phosphorus removal.
- The impact of nitrite, a key intermediate, on anoxic phosphorus uptake and the stability of DPR processes remains incompletely understood.
- Investigating microbial responses to nitrite stress is crucial for optimizing DPR systems in high-nitrogen wastewater treatment.
Purpose of the Study:
- To evaluate the total phosphorus removal performance of DPR under varying levels of nitrite stress.
- To analyze the shifts in microbial community structure and function in response to nitrite stress.
- To identify key microbial players and mechanisms involved in mitigating nitrite inhibition.
Main Methods:
- Analysis of total phosphorus removal efficiency across different nitrite concentrations.
- Microbiome analysis using 186 sludge samples to assess community structure and dynamics.
- Correlation analysis between microbial community shifts and process performance under nitrite stress.
Main Results:
- Total phosphorus removal rates and dominant bacterial taxa showed resilience under moderate nitrite stress.
- High nitrite stress induced a significant community-state shift, characterized by increased species cooperation.
- This community shift led to process instability and reduced total phosphorus removal efficiency.
- Genera OLB8 and Zoogloea were identified as potentially crucial for mitigating nitrite stress through enhanced metabolism.
Conclusions:
- Nitrite stress can destabilize DPR processes by inducing microbial community shifts, despite initial resilience.
- Understanding microbial responses, particularly the roles of genera like OLB8 and Zoogloea, is vital for designing robust high-nitrogen wastewater treatment systems.
- The findings provide a basis for optimizing DPR reactor design and operation to manage nitrite inhibition effectively.
