Abstract:
Anthropogenic deoxygenation of the Baltic Sea caused major declines in demersal and benthic habitat quality with consequent impacts on biodiversity and ecosystem services. Using Baltic cod otolith chemical proxies of hypoxia, salinity, and fish metabolic status and growth, we tracked changes from baseline conditions in the late Neolithic (4500 BP) and early twentieth century to the present, in order to understand how recent, accelerating climate change has affected this key species. Otolith hypoxia proxies (Mn:Mg) increased with expanding anoxic water volumes, but decreased with increasing salinity indexed by otolith Sr:Ca. Metabolic status proxied by otolith Mg:Ca and reconstructed growth were positively related to dissolved oxygen percent saturation, with particularly severe declines since 2010. This long-term record of otolith indicators provides further evidence of a profound state change in oxygen for the worse, in one of the world\'s largest inland seas. Spreading hypoxia due to climate warming will likely impair fish populations globally and evidence can be tracked with otolith chemical biomarkers.
摘要:
波罗的海的人为脱氧导致底栖和底栖栖息地质量大幅下降,从而影响生物多样性和生态系统服务。使用波罗的海鳕鱼耳石化学代理缺氧,盐度,鱼类的代谢状态和生长,我们追踪了新石器时代晚期(4500BP)和20世纪早期到现在的基线条件的变化,为了了解最近,加速的气候变化影响了这个关键物种。耳石缺氧代理(Mn:Mg)随着缺氧水量的增加而增加,但随着耳石Sr:Ca的盐度增加而降低。耳石Mg:Ca和重建的生长所代表的代谢状态与溶解氧饱和度呈正相关,自2010年以来特别严重的下降。耳石指标的长期记录提供了进一步的证据,表明氧气的状态发生了深远的变化,在世界上最大的内陆海之一。由于气候变暖而导致的缺氧扩散可能会损害全球鱼类种群,并且可以通过耳石化学生物标志物来追踪证据。