Shellfish and algae: Climate change mitigation through green and valuable foods

Food safety issues have become increasingly severe, while the global population continues to grow. Shellfish and algae (SA), as sustainable and environmentally friendly foods, have great significance in helping countries worldwide achieve the goal of carbon neutrality. However, there is still a gap in quantitatively evaluating the carbon neutrality of SA farming. To address this gap, this study evaluated global SA farming, including aspects of carbon sinks, the drivers of carbon removal, value-added ecosystem services, and the performance of carbon reduction mechanisms. Results revealed that (1) 16.57 Mt. CO₂-eq/yr were sequestered worldwide via SA farming during 2000-2020, wherein Asia was the dominant contributor to SA carbon sinks due to the abundance of production. (2) Product values were the main drivers for carbon sinks via SA farming. (3) The annual added value of SA was 501.40 million dollars during 2000-2020, of which algae farming accounted for the highest proportion. Mussel and laver were promising due to their excellent ability for carbon removal and added value. (4) It is estimated that SA farming can reduce carbon within a range from 47.72 Mt. CO₂-eq/yr to 1539.95 Mt. CO₂-eq/yr in 2021-2035. In general, the farming of SA is a promising way to respond to the call for carbon neutrality and food safety assurance worldwide, while the preference for mussel and laver can be further explored.