据近期《自然—地球科学》上的一项研究显示，南大洋软体动物的外壳正呈现出严重溶解的迹象。这表明海洋酸化对海洋生态系统的影响正在显现。
Geraint Tarling等人对环绕南极洲的南大洋表层水域中活软体动物的外壳进行检查，发现从海洋酸性程度较大区域获取的外壳样本显著表现出了溶解的征兆。他们认为这种溶解产生的原因是二氧化碳富集的深层水与受大气中二氧化碳影响的表层水的共同作用。
Justin Ries在一篇评论文章中称该酸腐蚀记录“或许揭示着南大洋大部分区域中表层水所储藏着的物质”。(生物谷Bioon.com)
DOI:10.1038/ngeo1635
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Extensive dissolution of live pteropods in the Southern Ocean
N. Bednaršek,1, 2, 3 G. A. Tarling,1 D. C. E. Bakker,2 S. Fielding,1 E. M. Jones,4 H. J. Venables,1 P. Ward,1 A. Kuzirian,5 B. Lézé,2 R. A. Feely6 & E. J. Murphy1
The carbonate chemistry of the surface ocean is rapidly changing with ocean acidification, a result of human activities1. In the upper layers of the Southern Ocean, aragonite—a metastable form of calcium carbonate with rapid dissolution kinetics—may become undersaturated by 2050 (ref. 2). Aragonite undersaturation is likely to affect aragonite-shelled organisms, which can dominate surface water communities in polar regions3. Here we present analyses of specimens of the pteropod Limacina helicina antarctica that were extracted live from the Southern Ocean early in 2008. We sampled from the top 200 m of the water column, where aragonite saturation levels were around 1, as upwelled deep water is mixed with surface water containing anthropogenic CO2. Comparing the shell structure with samples from aragonite-supersaturated regions elsewhere under a scanning electron microscope, we found severe levels of shell dissolution in the undersaturated region alone. According to laboratory incubations of intact samples with a range of aragonite saturation levels, eight days of incubation in aragonite saturation levels of 0.94–1.12 produces equivalent levels of dissolution. As deep-water upwelling and CO2 absorption by surface waters is likely to increase as a result of human activities2, 4, we conclude that upper ocean regions where aragonite-shelled organisms are affected by dissolution are likely to expand.
