Understanding and mitigating greenhouse gas emissions in aquaculture: a review of emission sources, regional trends and sustainability pathways

Aquaculture is increasingly important in global food production; however, its environmental impacts, particularly greenhouse gas (GHG) emissions, are subject to increasing scrutiny. This literature review synthesizes current research on GHG emissions from aquaculture, identifying key emission sources, species-specific emission patterns, geographical research trends and mitigation approaches. A systematic search was performed using the Web of Science, using search terms associated with aquaculture and GHGs. The search yielded 1821 publications. Subsequent analysis indicated a marked rise in academic interest since 2000, reaching a peak of 222 publications in 2023. Geographically, China has dominated publication output, followed by the USA, Australia and Norway. Major themes have included quantifying emissions of CO2, CH4 and N2O across species, such as mussels, salmon, shrimp, and tilapia. Seaweed and bivalves have often been identified as low-emission or carbon-sequestering organisms, whereas intensive production of shrimp and catfish tended to be associated with elevated emission levels. Notable mitigation measures included optimized feed composition, integrated multi-trophic aquaculture and adoption of renewable energy technologies. This review also highlights the lack of research in regions such as Africa and stresses the importance of adopting standardized methodologies for emission measurement and life cycle assessment. This work offers research-informed and policy-relevant guidance to advance low-carbon aquaculture systems in line with global climate objectives.