应用镭-226解读南极普里兹湾表层水的 来源与运移

郑敏芳; 陈敏; 杨俊鸿; 张润; 马嫱; 杨伟锋; 邱雨生

应用镭-226解读南极普里兹湾表层水的来源与运移

1.
厦门大学海洋与环境学院,福建厦门 361005
2.
厦门大学海洋与环境学院,福建厦门 361005;厦门大学近海海洋环境科学国家重点实验室,福建厦门 361005

基金项目: 国际极地年中国行动计划项目;国际海底区域研究开发"十一五"项目(DYXM-115-02-4-06);福建省自然科学基金杰出青年基金项目(2009J06026)。

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出版历程
- 收稿日期: 2009-04-29

Radium-226 as a tracer for the source and movement of water masses in the Prydz Bay of Antarctica

1.
College of Oceanography and Environmental Science, Xiamen University, Xiamen 361005, China
2.
College of Oceanography and Environmental Science, Xiamen University, Xiamen 361005, China;State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China

摘要

摘要: 中国第22次南极科学考察航次(2005年12月至2006年1月)期间,利用Mn-纤维富集大体积表层海水中的Ra同位素,并通过²²²Rn直接射气法测量²²⁶Ra的比活度,结果表明,普里兹湾表层水的²²⁶Ra比活度变化为0.92~2.09 Bq/m³,平均值为1.61 Bq/m³,在深海区域表现出²²⁶Ra含量高的特征。从空间分布看,表层水²²⁶Ra比活度呈现出由湾内向湾外增加的反常态势,反映出不同Ra含量水团的混合影响。²²⁶Ra比活度与盐度的关系证实研究海域表层水的Ra含量主要受三种端元水体的混合所控制:其一为具有镭含量高、盐度高特征的南极夏季表层水;其二为低镭、低盐特征的冰融水;其三为高盐、中等镭含量的普里兹湾中深层水,该水体的²²⁶Ra纯粹由海底沉积物间隙水向上扩散所维持。结合S-²²⁶Ra示踪体系及上述三端元混合模型,计算出各组成水体的比例并描绘出它们的空间分布。南极夏季表层水的份额由湾外向湾内逐渐降低,并且在68°E断面向南影响范围较大;冰融水的比例由湾内向湾外降低,并且在湾内东部的高温水体中具有最大贡献;普里兹湾中深层水中受沉积物镭来源影响比较显著的区域出现在湾内西北部,其影响向湾外逐渐降低。冰融水与普里兹湾中深层水份额分别于普里兹湾湾顶东、西部出现高值的分布特征证实埃默里冰架前沿海流东进、西出的运移规律。
- 南极普里兹湾 /
- ²²⁶Ra /
- 水团来源
Abstract: Surface waters were collected from the Prydz Bay of Antarctica for measurements of ²²⁶Ra activities during the 22nd China’s antarctic research expedition (from December 2005 to January 2006).²²⁶Ra in large volume waters was extracted by Mn-fibers and measured by a ²²²Rn emanation method.Results show that ²²⁶Ra activity in the Prydz Bay ranges from 0.92 to 2.09 Bq/m³ with an average of 1.61 Bq/m³.High contents of ²²⁶Ra were observed at deep open-ocean stations, which induced an offshore increase of ²²⁶Ra activity.This unique distribution pattern in the Prydz Bay was ascribed to the influence of water masses with different ²²⁶Ra signals.Based on the relationship between ²²⁶Ra activity and salinity, three water masses were identified: (1) the antarctic summer surface water (AASSW) with a characteristics of high salinity and high content of ²²⁶Ra; (2) the ice-melted water (IMW) with a characteristics of low salinity and low content of ²²⁶Ra; and (3) the Prydz Bay deep water (PDW) with a characteristics of high salinity and intermediate content of ²²⁶Ra.²²⁶Ra in the Prydz Bay deep water was assumed to be maintained only by the supply from the seabed sediments.The fractions of the above three water masses were estimated by mass balance calculation of salinity and ²²⁶Ra activity.Results show that the AASSW fractions decrease from the deep open ocean to inshore, while the IMW and PDW fractions increase.The maximum fractions of the IMW and the PDW occur in the eastern and the western regions along the front of the Amery ice shelf, respectively, testifying the major flow into the shelf occurs at the eastern end and exits from the west.
- Prydz Bay /
- ²²⁶Ra /
- water masses

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参考文献(40)

KU T L, LUO S.New appraisal of radium-226 as a large-scale oceanic mixing tracer [J].Journal of Geophysical Research, 1994, 99(C5): 10255—10273.

CHUNG Y.Radium-barium-silica correlations and a two dimensional radium model for the world ocean [J].Earth and Planetary Science Letters, 1980, 49: 309—318.

KU T L, HUH C A, CHEN P S.Meridional distribution of ²²⁶Ra in the eastern Pacific along GEOSECS cruise tracks [J].Earth and Planetary Science Letters, 1980, 49: 293—308.

NOZAKI Y, KASEMSUPAYA V, TSUBOTA H. Mean residence time of the shelf water in the East China and the Yellow Seas determined by ²²⁸Ra/²²⁶Ra measurements [J].Geophysical Research Letters, 1989, 16: 1297—1300.

CHEN M, XING N, HUANG Y P, et al.The mean residence time of river water in the Canada Basin [J].Chinese Science Bulletin, 2008, 53(5): 777—783.

YANG J H, CHEN M, QIU Y S, et al.²²⁶Ra evidence for the ecosystem shift over the past 40 years in the North Pacific Subtropical Gyre [J].Chinese Science Bulletin, 2007, 52(6): 832—838.

BROECKER W S, LI Y H, CROMWELL J.Radium-226 and radon-222: concentration in Atlantic and Pacific Oceans [J].Science, 1967, 158: 1307—1310.

KU T L, LI Y H, MATHIEU G G, et al.Radium in the Indian-Antarctic Ocean south of Australia [J].Journal of Geophysical Research, 1970, 75: 5286—5292.

CHUNG Y, CRAIG H.Ra-226 in the eastern equatorial Pacific Ocean [J].Earth and Planetary Science Letters, 1973, 17: 306—318.

CHUNG Y.Radium-226 and Ra-Ba relationships in Antarctic and Pacific waters [J].Earth and Planetary Science Letters, 1974, 23: 125—135.

BROECKER W S, GODDARD J, SARMIENTO J L.The distribution of ²²⁶Ra in the Atlantic Ocean [J].Earth and Planetary Science Letters, 1976, 32: 220—235.

KU T L, LIN M C .²²⁶Ra distribution in the Antarctic Ocean [J].Earth and Planetary Science Letters, 1976, 31: 236—248.

CHUNG Y.²¹⁰Pb and ²²⁶Ra distributions in the circumpolar waters [J].Earth and Planetary Science Letters, 1981, 55: 205—216.

CHUNG Y.²²⁶Ra in the western Indian Ocean [J].Earth and Planetary Science Letters, 1987, 85: 11—27.

CHUNG Y, APPLEQUIST M D.²²⁶Ra and ²¹⁰Pb in the Weddell Sea [J].Earth and Planetary Science Letters, 1980, 49: 401—410.

HANFLAND C.Radium-226 and Radium-228 in the Atlantic sector of the Southern Ocean [M].Rep Polar Mar Res, 2002, 431:1—135.

CHARETTE M A, GONNEEA M E, MORRIS P, et al.Radium isotopes as tracers of iron sources fueling a Southern Ocean phytoplankton bloom [J].Deep-Sea ResearchII, 2007, 54:1989—1998.

BEEK P, BOURQUIN M, REYSS J L, et al.Radium isotopes to investigate the water mass pathways on the Kerguelen Plateau (Southern Ocean) [J].Deep-Sea ResearchII, 2008, 55:622—637.

尹明端, 曾文义, 吴世炎, 等.南极普里兹湾海域铀系同位素的分布 [J].极地研究, 2004, 16(1):11—21.

曾宪章, 曾文义, 尹明端, 等. 示踪物在指示南大洋水团组成和运动路径中的作用 //陈立奇. 南极地区对全球变化的响应与反馈作用研究.北京: 海洋出版社, 2004:72—86.

董兆乾, 蒲书箴, 胡筱敏, 等. 南极普里兹湾及其邻近海域的水团研究 //陈立奇. 南极地区对全球变化的响应与反馈作用研究. 北京: 海洋出版社, 2004:13—25.

蒲书箴, 胡筱敏, 董兆乾, 等.普里兹湾邻近海域的物理海洋学特征和海洋锋面的变化 //陈立奇. 南极地区对全球变化的响应与反馈作用研究.北京: 海洋出版社, 2004: 36—58.

乐肯堂, 史久新, 于康玲, 等.普里兹湾区水团和环流时空变化的若干问题 [J].海洋科学集刊, 1998, 40: 43—54.

史久新, 赵进平.中国南大洋水团、环流和海冰研究进展(1995—2002) [J].海洋科学进展, 2002, 20(4): 116—126.

谢永臻, 黄奕普, 施文远, 等.天然水体中²²⁶Ra,²²⁸Ra的联合富集与测定 [J].厦门大学学报(自然科学版), 1994, 33(sup): 86—90.

邢娜, 陈敏, 黄奕普, 等.北冰洋、白令海²²⁶Ra的分布及其水文学意义 [J].中国科学:D辑, 2002, 32 (5): 430—440.

谢永臻, 施文远, 黄奕普, 等.南海东北部海水中的²²⁶Ra //台湾海峡及邻近海域海洋科学讨论会论文集编辑委员会.台湾海峡及邻近海域海洋科学讨论会论文集.北京: 海洋出版社, 1995: 225—239.

谢永臻, 黄奕普, 邱雨生, 等.南沙海域表层水中²²⁶Ra的分布 //中国科学院南沙综合科学考察队.南沙群岛海域的同位素海洋化学.北京: 海洋出版社, 1996: 63—69.

黄奕普, 陈性保, 姜德盛, 等.1994航次南沙海域²²⁶Ra的分布与变化 //中国科学院南沙综合科学考察队.南沙群岛海域的同位素海洋化学.北京: 海洋出版社, 1996: 79—88.

西村雅吉, 角皆静男, 乘木新一郎. 海洋化学—化学で海を解く[M].东京: 产业图书株式会社, 1993: 1—50.

蒲书箴, 胡筱敏, 董兆乾, 等.普里兹湾附近绕极深层水的底层水及其运动特征 [J].海洋学报, 2002, 24(3): 1—8.

MACDONALD R W, PATON D W, CARMACK E C, et al.The freshwater budget and under-ice spreading of the Mackenzie River water in the Canadian Beaufort Sea based on salinity and ¹⁸O/¹⁶O measurements in water and ice [J].Journal of Geophysical Research, 1995, 100(C1): 895—919.

陈敏, 黄奕普, 金明明, 等. 加拿大海盆上、下跃层水形成机制的同位素示踪 [J]. 中国科学:D辑, 2003, 33(2): 127—138.

SMITH N.Water masses and circulation in the region of Prydz Bay, Antarctica [J].Deep-Sea Research, 1984, 31(9): 1121—1147.

乐肯堂, 史久新, 于康玲.普里兹湾区水团和热盐结构的分析 [J].海洋与湖沼, 1996, 27(3): 229—236.

陈明剑, 侍茂崇, 高郭平.普里兹湾大陆架外水域水文物理特征 [J].青岛海洋大学学报, 1995(增刊):235—249.

蒲书箴, 董兆乾, 胡筱敏, 等.普里兹湾海域的夏季上层水及其北向运动 [J].极地研究, 2000, 12(3): 167—168.

陈红霞, 潘增弟, 矫玉田, 等.埃默里冰架前缘水的特性和海流结构 [J].极地研究, 2005, 17(2): 139—148.

蔡平河, 黄奕普, 陈敏, 等. 南极普里兹湾海水中冰川融化水和海冰融化水的含量 [J]. 中国科学:D辑, 2002, 32(8): 695—704.

LEFFANUE H, CRAVEN M.Circulation and water masses from current meter and T/S measurements at the Amery ice shelf . SMEDSRUD L H.FRISP Report No 15. Bergen: Bjerknes Centre for Climate Research,2004: 1—7.

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