Comparison of carbon footprint of diploid and triploid oysters based on life cycle assessment

Background China is a major aquaculture country. In the context of carbon peak and carbon neutrality, it is necessary to accelerate the establishment of management systems for the carbon footprints (CFP) and enrich the practice of CFP barcodes for products, in order to adapt to the trend of low-carbon economy of the future.

Objective The present study aims to establish and optimize the CFP accounting method for aquatic products, as well as to compare the CFP of major oyster products in Fujian Province.

Methods Here, the CFP of diploid oyster (Crassostrea angulate) and triploid oyster (C. angulate ♂ × Crassostrea gigas ♀) were compared by life cycle assessment. The inventory analysis included the periods of breeding in the factory, farming in the sea and cultivation marketing.

Results The results showed that the “cradle-to-gate” CFP of 1 ton diploid and triploid oysters were −210.79 kg CO₂eq and −37.92 kg CO₂eq, respectively. The “cradle-to-grave” CFP of 1 ton diploid and triploid oyster were −93.89 kg CO₂eq and 78.98 kg CO₂eq, respectively. The main carbon emissions of cultured oyster products came from the power consumption in the breeding period and the emission of farming facilities in the farming period. In the future, carbon emissions can be further reduced by increasing renewable energy and using new materials in farming facilities.

Conclusion Compared with other aquaculture products, oysters have lower carbon emissions than most seafood, suggesting its environment-friendly superiority.

Significance This study will supporting the scientific management of aquaculture product carbon emissions and development of CFP assessment methods, which is conductive to the green transformation of aquaculture under the background of carbon peaking and carbon neutrality.