气候变化和过度捕捞增加了海洋捕食者的神经毒素
Amina T Schartup1,2, Colin P Thackray3, Asif Qureshi4
1Harvard John A. Paulson School of Engineering & Applied Sciences, Harvard University, Cambridge, MA, USA. aschartup@ucsd.edu.
Nature
|August 9, 2019
概括
由于过度捕捞和海洋变暖, 海鲜中的甲基 (MeHg) 是一种神经毒素, 这种MeHg生物积累的增加对人类健康构成威胁,超过了减排的努力.
科学领域:
- 环境科学
- 海洋生物学
- 毒理学
背景情况:
- 海鲜是全球超过30亿人的主要营养来源.
- 鱼类中的甲基 (MeHg) 具有显著的神经毒性风险,金枪鱼是美国的主要暴露来源.
- 海洋中的沉积和生物放大导致捕食鱼的MeHg度高.
研究的目的:
- 评估生态系统变化对海洋捕食者的MeHg生物积累的影响.
- 评估过度捕捞和海洋变暖如何影响商业重要鱼类的MeHg水平.
- 通过考虑生态因素,为全球减少的政策目标提供信息.
主要方法:
- 通过30多年的海洋生态系统数据.
- 使用生态系统建模来模拟MeHg生物积累.
- 分析了大西洋鱼的饮食变化和大西洋蓝鱼的温度影响.
主要成果:
- 由于过度捕捞导致的饮食变化, 大西洋鱼的含量从20世纪70年代增加了23%.
- 大西洋蓝鱼可能会因海水温度升高而增加56%的组织MeHg.
- 预计鱼的MeHg增加超过了通过降低海水MeHg度而实现的减少.
结论:
- 海洋变暖和渔业管理是未来海洋捕食者的MeHg水平的主要驱动因素.
- 由于正在发生的生态系统变化,目前的全球政策目标可能无法充分解决MeHg风险.
- 有效的减缓策略需要紧急考虑生态因素.
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