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Updated: May 15, 2026
08:05
Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
Nitrogen transformations in intensive aquaculture system and its implication to climate change through nitrous oxide
Zhen Hu1, Jae Woo Lee, Kartik Chandran
1Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
Bioresource Technology
|January 15, 2013
Summary
Aquaculture systems emit nitrous oxide (N2O), a greenhouse gas. Lower dissolved oxygen and higher feeding rates in Chinese catfish systems significantly increased N2O emissions, linked to nitrification and denitrification processes.
Area of Science:
- Environmental Science
- Aquaculture Science
- Climate Science
Background:
- Aquaculture expansion poses environmental risks like eutrophication and climate change.
- Nitrogen transformations and nitrous oxide (N2O) emissions in aquaculture are understudied.
- Nitrous oxide is a potent greenhouse gas and ozone-depleting substance.
Purpose of the Study:
- To investigate nitrogen transformations and quantify N2O emissions in intensive Chinese catfish aquaculture.
- To identify key factors influencing N2O emissions in these systems.
Main Methods:
- Laboratory-scale Chinese catfish (Clarias fuscus) aquaculture systems were established.
- Nitrogen transformations and N2O emissions were identified and quantified.
- Correlations between N2O emission rates and environmental parameters (e.g., DO, NO2-, TAN) were analyzed.
Main Results:
- Approximately 1.3% of the total nitrogen input was emitted as N2O gas.
- N2O emissions were significantly higher in systems with lower dissolved oxygen (DO) concentrations and higher feeding rates.
- Nitrification and denitrification were identified as the primary sources of N2O emissions.
- Nitrite (NO2-), DO, and total ammonia nitrogen (TAN) concentrations were key factors correlated with N2O emission rates.
Conclusions:
- Intensive Chinese catfish aquaculture can be a notable source of N2O emissions.
- Optimizing DO levels and feeding management is crucial for mitigating N2O release.
- Understanding nitrogen cycling, including nitrification and denitrification, is essential for sustainable aquaculture practices.
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