冰雪融化导致海水pH值和海平面变化的硼同位素证据  

Boron isotopic evidence for contribution of melting ice to ocean pH value and sea level during global warming

作　　者：刘卫国[1] 肖军[1] HEMMING N G 彭子城 肖应凯[4] 安芷生[1] 

机构地区：[1]中国科学院地球环境研究所黄土与第四纪地质国家重点实验室,西安710075 [2]Lamont-Doherty Earth Observatory of Columbia University [3]中国科学技术大学地球与空间学院,合肥230026 [4]中国科学院青海盐湖研究所,西宁810008

出　　处：《地球环境学报》2010年第1期43-47,共5页Journal of Earth Environment

基　　金：黄土与第四纪地质国家重点实验室项目(SKLLQG0909)

摘　　要：采用热电离质谱(TIMS)对中国南海珊瑚硼同位素进行了测定,结果表明珊瑚δ^(11)B的变化范围为22.2‰~25.5‰,珊瑚的δ^(11)B与硼浓度呈现正相关。在讨论珊瑚δ^(11)B与海水pH值、珊瑚硼浓度与年龄之间关系的基础上,重点讨论了极地冰雪融化对珊瑚礁硼同位素组成变化的可能影响,即,由于全球变暖导致的冰雪融化对海水pH值减小、海面上升的贡献。研究者认为:中国南海珊瑚硼同位素低值与6000年前高海平面相对应,具有低碱度的冰雪融水是海水pH值减小的因素之一,由于全球变暖导致的冰雪融化的贡献有可能是海水pH值和珊瑚硼同位素变化的一个重要影响因素。据此,提出南海珊瑚硼同位素组成有可能成为反映中国南海海平面变化的一个代用指标。Boron isotopic compositions and concentrations in corals from the South China Sea have been investigated by using thermal ionization mass spectrometry. The results show that the boron isotopic compositions （δ^11B） of corals vary in a range from 22.2‰ to 25.5‰, having a positive relation with boron concentrations. The relations among δ^11 B, pH values, boron concentrations and age have been observed and discussed. In addition, another factor was discussed that the contributions of melt water derived from global warming reduced seawater pH as well as raised the sea level. The results show that the low δ^11B value of corals in South China Sea is consistent with high sea level at about 6000 years before present. A contribution of melting ice associated with global warming should be considered as a factor for variation of pH and δ^11B.

关 键 词：硼同位素 PH值 高海平面 冰雪融化 

分 类 号：P736.44[天文地球—海洋地质] P731[天文地球—海洋科学]