Institute for the Oceans and Fisheries, The University of British Columbia, Vancouver, British Columbia, Canada.
Center for Limnology, University of Wisconsin, Madison, Wisconsin, USA.
Glob Chang Biol. 2022 Nov;28(21):6254-6267. doi: 10.1111/gcb.16368. Epub 2022 Sep 1.
Rebuilding overexploited marine populations is an important step to achieve the United Nations' Sustainable Development Goal 14-Life Below Water. Mitigating major human pressures is required to achieve rebuilding goals. Climate change is one such key pressure, impacting fish and invertebrate populations by changing their biomass and biogeography. Here, combining projection from a dynamic bioclimate envelope model with published estimates of status of exploited populations from a catch-based analysis, we analyze the effects of different global warming and fishing levels on biomass rebuilding for the exploited species in 226 marine ecoregions of the world. Fifty three percent (121) of the marine ecoregions have significant (at 5% level) relationship between biomass and global warming level. Without climate change and under a target fishing mortality rate relative to the level required for maximum sustainable yield of 0.75, we project biomass rebuilding of 1.7-2.7 times (interquartile range) of current (average 2014-2018) levels across marine ecoregions. When global warming level is at 1.5 and 2.6°C, respectively, such biomass rebuilding drops to 1.4-2.0 and 1.1-1.5 times of current levels, with 10% and 25% of the ecoregions showing no biomass rebuilding, respectively. Marine ecoregions where biomass rebuilding is largely impacted by climate change are in West Africa, the Indo-Pacific, the central and south Pacific, and the Eastern Tropical Pacific. Coastal communities in these ecoregions are highly dependent on fisheries for livelihoods and nutrition security. Lowering the targeted fishing level and keeping global warming below 1.5°C are projected to enable more climate-sensitive ecoregions to rebuild biomass. However, our findings also underscore the need to resolve trade-offs between climate-resilient biomass rebuilding and the high near-term demand for seafood to support the well-being of coastal communities across the tropics.
重建过度捕捞的海洋种群是实现联合国可持续发展目标 14“水下生物”的重要步骤。为了实现重建目标，需要减轻主要的人类压力。气候变化就是这样一个关键压力，它通过改变鱼类和无脊椎动物的生物量和生物地理学来影响它们的种群。在这里，我们结合动态生物气候包络模型的预测结果和基于捕捞量分析的已开发种群的状态的公布估计值，分析了不同全球变暖水平和捕捞水平对世界 226 个海洋生态区中已开发物种生物量重建的影响。在这些海洋生态区中，有 53%（121 个）的海洋生态区的生物量与全球变暖水平之间存在显著关系（在 5%的水平上）。如果没有气候变化，并且目标捕捞死亡率相对于最大可持续产量的水平为 0.75，我们预计在全球变暖水平分别为 1.5°C 和 2.6°C 的情况下，海洋生态区的生物量将分别比当前（2014-2018 年平均水平）水平重建 1.7-2.7 倍（四分位距）和 1.4-2.0 倍和 1.1-1.5 倍，分别有 10%和 25%的生态区没有生物量重建。生物量重建受气候变化影响较大的海洋生态区位于西非、印度-太平洋、中太平洋和南太平洋以及东热带太平洋。这些生态区的沿海社区高度依赖渔业来维持生计和保障营养安全。降低目标捕捞水平和将全球变暖控制在 1.5°C 以下，预计将使更多对气候敏感的生态区能够重建生物量。然而，我们的研究结果也强调了需要在气候适应型生物量重建和支持热带地区沿海社区福祉的高短期海鲜需求之间做出权衡。
