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Updated: Jan 27, 2026
09:24
Assembly and Tracking of Microbial Community Development within a Microwell Array Platform
Published on: June 6, 2017
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Nitrogen loading fluctuations impact microbial community assembly and functional redundancy in anammox reactors.
Hoang Phuc Trinh1, Sang-Hoon Lee1, Hee-Deung Park2
1School of Civil, Environmental and Architectural Engineering, Korea University, Seoul 02841, South Korea.
Water Research
|January 25, 2026
Summary
Moderate nitrogen loading rate (NLR) fluctuations boost anammox system performance and resilience. Severe NLR disturbances, however, impair nitrogen removal and microbial stability, highlighting the critical impact of disturbance intensity on wastewater treatment ecosystems.
Area of Science:
- Environmental Microbiology
- Wastewater Treatment Engineering
- Ecosystem Ecology
Background:
- Nitrogen loading rate (NLR) fluctuations are common in full-scale anammox systems, potentially compromising process stability.
- The ecological mechanisms governing system resilience under disturbed conditions are not fully understood.
- Understanding these mechanisms is crucial for optimizing nitrogen removal in wastewater treatment.
Purpose of the Study:
- To investigate the influence of different intensities of NLR disturbances on microbial community assembly and functional redundancy in anammox systems.
- To correlate ecological responses with nitrogen removal performance under stable and fluctuating NLR conditions.
- To elucidate the relationship between disturbance intensity, microbial ecology, and system robustness.
Main Methods:
- Operation of two anammox sequencing batch reactors for 180 days under stable (R1) and fluctuating (R2) NLR conditions.
- Monitoring of nitrogen removal efficiency and microbial community composition.
- Metagenome-assembled genome analysis to assess nitrogen metabolism genes.
- Neutral community modeling to determine microbial assembly processes (stochastic vs. deterministic).
Main Results:
- Moderate NLR fluctuations (1.4-fold) enhanced nitrogen removal (up to 99.7%) and anammox bacteria abundance (26.4%).
- Severe NLR fluctuations (2.0-fold) led to decreased nitrogen removal (72.2%) and anammox bacteria abundance (7.1%).
- NLR disturbances altered nitrogen metabolism gene expression and shifted microbial assembly from stochastic to deterministic processes with increasing disturbance intensity.
Conclusions:
- Microbial community assembly and functional redundancy exhibit non-linear responses to NLR disturbance intensity.
- Moderate NLR fluctuations can enhance anammox system performance and resilience by promoting stochastic processes and functional redundancy.
- Severe NLR disturbances degrade performance and reduce buffering capacity, necessitating careful operational strategies for robust nitrogen removal.
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