Data for: Projecting global mariculture production and adaptation pathways under climate change

The sustainability of global seafood supply to meet increasing demand is facing several challenges, including increasing consumption levels due to a growing human population, fisheries resources over-exploitation and climate change. While growth in seafood production from capture fisheries is limited, global mariculture production is expanding. However, climate change poses risks to the potential seafood production from mariculture. Here, we apply a global mariculture production model that accounts for changing ocean conditions, suitable marine area for farming, fishmeal and fish oil production, farmed species dietary demand, farmed fish price, and global seafood demand to project mariculture production under two climate and socioeconomic scenarios. We include 85 farmed marine fish and molluscs species, representing about 70% of all mariculture production in 2015. Results show positive global mariculture production changes by the mid and end of the 21st century relative to the 2000s under the SSP1-2.6 scenario with an increase of 33%±6 and 17%±5 respectively. However, under the SSP5-8.5 scenario, an increase of 8%±5 is projected, which peaks by the mid-century and declines by 16%±5 towards the end of the 21st century. More than 25% of mariculture-producing nations are projected to lose 40-90% of their current mariculture production potential under SSP5-8.5 by mid-century. Projected impacts are mainly due to the direct ocean warming effects on farmed species and suitable marine areas, and the indirect impacts of changing availability of forage fishes supplies to produce aquafeed. Fishmeal replacement with alternative protein can lower climate impacts on a subset of finfish production. However, such adaptation measures do not apply to regions dominated by non-feed-based farming (i.e., molluscs) and regions losing substantial marine areas suitable for mariculture. Our study highlights the importance of strong mitigation efforts and the need for different climate adaptation options tailored to the diversity of mariculture systems, to support climate-resilient mariculture development.

全球海产品供应为满足日益增长的需求所面临的可持续性挑战正日趋严峻，具体包括人口增长导致的消费水平提升、渔业资源过度开发以及气候变化。全球捕捞渔业（capture fisheries）的海产品生产增长已触及瓶颈，而全球海水养殖（mariculture）产量正持续扩张。然而，气候变化对海水养殖的潜在海产品产能构成了显著风险。本研究应用了一套全球海水养殖产量模型，该模型纳入海洋条件变化、适宜养殖海域面积、鱼粉（fishmeal）与鱼油（fish oil）产量、养殖物种的日粮需求、养殖鱼类价格以及全球海产品需求等核心要素，用以在两种气候与社会经济情景下预测海水养殖产量。本研究涵盖85种海水养殖鱼类与软体动物（molluscs），覆盖2015年全球海水养殖总产量约70%的份额。结果显示，在SSP1-2.6情景下，相较于2000年代，21世纪中叶与末期的全球海水养殖产量均实现正向增长，增幅分别为33%±6与17%±5。但在SSP5-8.5情景下，预计产量仅增长8%±5，于本世纪中叶达到峰值，随后至21世纪末期将下降16%±5。预计在SSP5-8.5情景下，到本世纪中叶，超过25%的海水养殖国家将损失其当前海水养殖生产潜力的40%至90%。预计产生的影响主要源于海洋变暖对养殖物种与适宜养殖海域的直接作用，以及用于生产水产饲料（aquafeed）的饵料鱼类供应变化所带来的间接影响。使用替代蛋白替代鱼粉可降低部分硬骨鱼类（finfish）生产所受的气候影响。但此类适应措施并不适用于以非饲料型养殖为主的区域（如软体动物养殖区域），以及大量丧失适宜海水养殖海域的区域。本研究强调了强化减排行动的重要性，以及针对海水养殖系统多样性定制差异化气候适应方案的必要性，以支持具备气候韧性的海水养殖发展。