Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK; MARBEC, University of Montpellier, CNRS, Ifremer, IRD, Montpellier, France.
Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK.
Curr Biol. 2024 Oct 21;34(20):4612-4622.e5. doi: 10.1016/j.cub.2024.08.031. Epub 2024 Sep 17.
Coral reefs support an incredible abundance and diversity of fish species, with reef-associated fisheries providing important sources of income, food, and dietary micronutrients to millions of people across the tropics. However, the rapid degradation of the world's coral reefs and the decline in their biodiversity may limit their capacity to supply nutritious and affordable seafood while meeting conservation goals for sustainability. Here, we conduct a global-scale analysis of how the nutritional quality of reef fish assemblages (nutritional contribution to the recommended daily intake of calcium, iron, and zinc contained in an average 100 g fish on the reef) relates to key environmental, socioeconomic, and ecological conditions, including two key metrics of fish biodiversity. Our global analysis of more than 1,600 tropical reefs reveals that fish trophic composition is a more important driver of micronutrient concentrations than socioeconomic and environmental conditions. Specifically, micronutrient density increases as the relative biomass of herbivores and detritivores increases at lower overall biomass or under high human pressure. This suggests that the provision of essential micronutrients can be maintained or even increase where fish biomass decreases, reinforcing the need for policies that ensure sustainable fishing, and that these micronutrients are retained locally for nutrition. Furthermore, we found a negative association between micronutrient density and two metrics of fish biodiversity, revealing an important nutrition-biodiversity trade-off. Protecting reefs with high levels of biodiversity maintains key ecosystem functions, whereas sustainable fisheries management in locations with high micronutrient density could sustain the essential supply of micronutrients to coastal human communities.
珊瑚礁支持着丰富多样的鱼类物种，与珊瑚礁相关的渔业为热带地区数百万人提供了重要的收入、食物和膳食微量营养素来源。然而，世界珊瑚礁的迅速退化和生物多样性的减少可能限制了它们在满足可持续性保护目标的同时，提供营养丰富且价格合理的海鲜的能力。在这里，我们对珊瑚鱼群的营养质量（即平均 100 克珊瑚鱼中所含钙、铁和锌的推荐日摄入量的营养贡献）如何与关键的环境、社会经济和生态条件相关联进行了全球范围的分析，包括两个鱼类生物多样性的关键指标。我们对 1600 多个热带珊瑚礁的全球分析表明，鱼类营养组成是微量元素浓度的更重要驱动因素，而不是社会经济和环境条件。具体来说，随着草食性和碎屑食性生物相对生物量的增加，或者在总生物量较低或人类压力较高的情况下，微量营养素密度会增加。这表明，在鱼类生物量减少的情况下，基本微量营养素的供应可以得到维持甚至增加，这就需要有政策来确保可持续渔业，并且这些微量营养素可以在当地保留以满足营养需求。此外，我们发现微量营养素密度与鱼类生物多样性的两个指标之间存在负相关关系，这揭示了一个重要的营养与生物多样性之间的权衡。保护生物多样性水平高的珊瑚礁可以维持关键的生态系统功能，而在微量营养素密度高的地方进行可持续渔业管理，可以维持向沿海人类社区提供基本微量营养素的供应。
