南大洋表层海水酸化研究进展

海洋酸化是全球变化的一个关注点,南大洋CO2吸收量占海洋对人为CO2的吸收量的30%—40%,同时,南大洋是缓冲能力较低、生态系统脆弱的高纬海域,所以,理解南大洋海水酸化过程及其控制因素就显得尤为重要。海水酸化引起海水中碳酸根离子(CO2-3)的浓度、碳酸钙饱和度(Ω)降低,这对成钙类生物碳酸钙(包括文石和方解石)的形成有害,最终可能对生态系统造成危害。了解海洋酸化的影响、预测酸化对海水碳酸盐体系和生态系统的影响具有重要意义。因此,本文对目前南大洋的开阔大洋区以及两个具有代表性的边缘海和海湾的酸化研究概况进行了梳理,试图对南大洋表层海水酸化的研究进行概述、展望未来南大洋海洋酸化研究趋势并提出一些亟须解决的问题。

Increased Acidification of the Southern Ocean Surface Waters

Ocean acidification (OA) has been an important research topic for a decade. Given that 30%—40% of ocean uptake of anthropogenic CO₂ occurs in the Southern Ocean (SO), and that the SO consists of high-latitude waters with low buffering capacity, a greater understanding of OA and the factors that affect it is particularly necessary. The OA-mediated decline in the seawater carbonate ion concentration and the carbonate saturation state, which dramatically impairs the ability of calcifying organisms to form calcium carbonate (including aragonite and calcite), will eventually have an adverse impact on the marine ecosystem. It is critical to understand the OA responses and predict their resulting impact on the carbonate system and ecosystem of the SO. In this article, we review studies of the acidification of SO surface waters and provide an overview of the acidification of the open ocean and representative marginal seas and bays of the SO. Additionally, we identify future trends in OA research, as well as some urgent problems.