极地研究

极地研究 ›› 2004, Vol. 16 ›› Issue (4): 295-309.

• 目次 • 上一篇    下一篇

海鸟活动在东南极中山站区莫愁湖沉积物中的记录

刘晓东;孙立广;谢周清;朱仁斌;尹雪斌;赵三平   

  • 出版日期:2004-12-30 发布日期:2004-12-30

GEOCHEMICAL EVIDENCE FOR THE INFLUENCE OF HISTORICAL SEA BIRD ACTIVITIES ON MOCHOU LAKE SEDIMENTS IN THE ZHONGSHAN STATION AREA, EAST ANTARCTICA

  • Online:2004-12-30 Published:2004-12-30

PDF (PC)

3486

被引次数

65

摘要：

本文对采自东南极拉斯曼丘陵中山站区的莫愁湖沉积物的元素、氨基酸和Sr同位素组成进行了详细的地球化学分析。结果表明莫愁湖沉积物中Zn、Cu、F、S、P、Se等六种元素具有共同的物质来源,其标型组合特征很可能揭示了莫愁湖沉积物在历史时期曾受到过企鹅等海鸟粪的影响,沉积物中酸溶相Sr同位素组成则确认了海洋源Sr的生物地球化学转移过程。酸溶相87Sr/86Sr值和研究区的新鲜海鸟粪酸溶相Sr同位素组成基本一致,都非常接近于海洋来源锶同位素组成(87Sr/86Sr=0.7092),并且沉积物中的生物元素Zn、Cu、F、S、P、Se含量和酸溶相Sr浓度具有非常高的统计相关性。酸溶相的87Sr/86Sr比值和反映湖泊中藻类等生物自然生成量的氨基酸含量表现出明显的负相关关系,进一步揭示了莫愁湖沉积物在历史时期曾受到企鹅等海鸟活动的影响。上述研究结果为更深入地研究该地区的生态、气候和环境的演变历史及其相互作用提供了有价值的参考资料。

关键词: 东南极;湖泊沉积物;元素;氨基酸;Sr同位素;海鸟粪

Abstract:

An 85cm long sediment sequence from Mochou Lake on Mirror Peninsula in the Larsemann Hills, East Antarctica, was investigated for elemental geochemistry, biogeochemistry and strontium isotopic compositions in the acid-insoluble and acid-soluble fractions. The geochemical characters of the elements in the bulk sediments and the ~~ ~87 Sr /~~ ~86 Sr ratios in the acid-soluble fractions suggest that the lake is strongly affected by historical sea bird activities in the catchment area. The depth distributions of amino acids in the sediments show that the sedimentary organic matter is not influenced by post-depositional diagenetic processes, and their concentrations mainly reflect the historical variation in the primary biogenic production produced in the lake. The ~~ ~87 Sr /~~ ~86 Sr ratios in the acid-soluble fraction of the sediments are found to be negative correlation with the concentrations of total amino acid, indicating the enormous role of historical seabirds on nutrient supply into the Mochou Lake. The present results provide a foundation for further studies at a large temporal scale on the reconstruction of lacustrine palaeoecology and the records of palaeoclimate and historical sea bird occupation in the catchment area of the lake.