Recently, the team led by Professor Dong Shuanglin from Fisheries College at OUC has made significant progress in sustainable aquaculture research. Their research findings, titled System-specific aquaculture annual growth rates can mitigate the trilemma of production, pollution and carbon dioxide emissions in China, were published in the renowned journal Nature Food.

The aquaculture industry contributes to over half of the global supply of aquatic products, with China alone accounting for an impressive 58% of total production. However, the intensive development driven by the use of pellet feed, oxygenation equipment and high-density stocking has resulted in a significant increase in production, along with a concerning rise in energy consumption, particularly in greenhouse gas emissions, as well as the discharge of nutrients like nitrogen and phosphorus. As a result, the aquaculture industry today is confronted with a difficult dilemma, where the pursuit of one specific goal often compromises others. For instance, while recirculating aquaculture systems (RAS) can effectively decrease water usage and pollution, the rise in energy consumption can cause higher carbon emissions. On the other hand, more energy-efficient methods like pond farming face significant pollution challenges. Thus, finding a way to navigate this impossible trilemma of increasing production, controlling pollution, and reducing emissions poses a serious challenge for aquaculture.

The research team led by Professor Dong Shuanglin found that strategically adjusting the aquaculture structure and practices may offer a solution to this impossible trilemma, and further proposed a phased approach to address the current challenge. The first phase, known as the ecological transition period (before 2050), involves recalibrating the average annual growth rates of key aquaculture systems to ensure that the industry develops in alignment with sustainability indicators. This may include promoting high-sustainability systems such as offshore non-fed aquaculture and deep-sea farming, while restricting less sustainable practices like nearshore fed aquaculture and feed-based pond farming, as well as upgrading land-based recirculating aquaculture systems (RAS). By 2050, it is anticipated that nitrogen emissions could be reduced by 6.9%, freshwater consumption decreased by 8.9%, and land use shrunk by 7.1% compared to 2021, with carbon emissions expected to peak in 2030 before declining rapidly along with the increased adoption of renewable energy. The second phase is the green aquaculture period (post-carbon neutrality), which entails a transition to clean energy-driven practices with a focus on reducing nutrient emissions in aquaculture systems. By 2050, production may see a modest increase of just 0.2%, but there will be significant reductions in resource consumption and energy use. The post-carbon neutrality era is expected to foster the development of innovative technologies, including algal feed production, methane collection in ponds, and AI-driven resource optimization.