白令海CO2源汇与控制因素研究进展

REVIEW OF RESEARCH ON AIR–SEA CO_2 FLUX AND ITS CONTROLLING FACTORS IN THE BERING SEA

白令海是北冰洋太平洋扇区的边缘海,是亚北极生态系统向北极生态系统过渡的典型区域,白令海CO_2源汇的研究可为高纬度边缘海相关的研究提供重要的参考。在全球持续变暖的背景下,白令海正在发生着一些气候和环境的变化,这些变化对CO_2源汇以及控制CO_2源汇的生物地球化学过程产生重要影响。对目前白令海CO_2源汇特征及其控制因素相关研究进行了归纳总结,预测了白令海CO_2源汇的未来变化趋势并提出了展望。以往的研究都认为白令海是一个大气CO_2的汇区,但是碳汇研究结果差异较大,最近的研究结果表明白令陆架区的碳汇约–6.81 Tg C·a^(–1)(1 Tg=10^(12)g),整个白令海的碳汇约–34 Tg C·a^(–1)。在未来白令海气候和环境变化继续加剧的条件下,使得白令海碳汇增强或减弱的因素将同时存在,因此,未来白令海的碳汇是增强还是减弱尚无定论。

The Bering Sea,in the Pacific sector of the Arctic Ocean,represents a typical area of transition from a sub-Arctic ecosystem to an Arctic ecosystem.The study of its CO_2 sources and sinks will provide an important reference for high-latitude continental margin regions.Within the context of global warming,the Bering Sea is undergoing climatic and environmental changes.The effects of these changes on both the CO_2 sources and sinks and the related biogeochemical processes of the area are considerable.This paper summarizes the CO_2 sources and sinks and their control mechanisms in the Bering Sea,describes the tendencies of those CO_2 sources and sinks,and predicts their future prospects.Previous studies have argued that the Bering Sea acts as a sink for atmospheric CO_2 but the results have been notably varied.Recent studies have reported that the CO_2 sinks on the Bering shelf and in the entire Bering Sea are about -6.81×10^(12) g C·a^(-1) and -34×10^(12) g C·a^(-1),respectively.However,if climatic and environmental changes continue to intensify in the future,conditions that could result in a decrease or in an increase in the magnitude of the CO_2 sink might exist simultaneously.Therefore,it remains inconclusive whether the function of the Bering Sea as a carbon sink will be enhanced or weakened in the future.