Trace element cycling and fluxes in the South Indian Ocean – a contribution to GEOTRACES

南印度洋的微量元素循环和通量——对 GEOTRACES 的贡献

• 批准号: 445391652
• 负责人: Professor Dr. Eric Achterberg
• 金额: --
• 依托单位: GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/445391652?language=en
• 关键词: Trace; element; cycling; fluxes; South

We propose to apply isotopes of radium (Ra), thorium and helium (He) to determine in detail the sources, fluxes and sinks of trace elements (TEs: Cd, Co, Cu, Fe, Mn, Mo, Ni, V, Zn) in the water column along a 23°S zonal section in the South Indian Ocean (SIO), one of the least studied ocean regions on earth. The application of isotopes of radium (224Ra, 223Ra, 228Ra 226Ra,), thorium (234Th 232Th,), helium (3He, 4He) will facilitate the study of the biogeochemical cycles of TEs, and given that some TEs act as micronutrients, allow an assessment of their interactions with surface ocean productivity and the carbon and nitrogen cycles. Combining measurements of TEs with Ra and 234Th isotopes as tracers for horizontal and vertical fluxes, 232Th as a tracer for dust inputs, and He isotopes as a tracer for hydrothermal inputs, we will investigate and quantify the supply pathways of TEs to the SIO from the atmosphere, continent (mainly the Zambezi River), sediments (on continental slopes), and ocean crust (hydrothermalism of Indian Ocean Ridge). The study will be based on samples collected during FS Sonne cruise SO-276 scheduled for July – August 2020 in the SIO from South Africa to Australia. Our investigations will be part of the internationally coordinated program GEOTRACES and will contribute to the Second Indian Ocean Expedition Program (IIOE-2). The outcome of this study will have global significance for understanding the chemical environment in which ecosystems operate.

利用镭（Ra）、钍（Th）和氦（He）同位素，详细研究了南印度洋（SIO）沿着23°S纬向断面水体中Cd、Co、Cu、Fe、Mn、Mo、Ni、V、Zn等微量元素的源、流和汇。镭（224 Ra，223 Ra，228 Ra，226 Ra，），钍（234 Th，232 Th，），氦（3 He，4 He）的同位素的应用将促进对TE的地球化学循环的研究，并考虑到一些TE作为微量营养素，允许评估它们与表层海洋生产力和碳和氮循环的相互作用。结合测量的TE与Ra和234 Th同位素作为示踪剂的水平和垂直通量，232 Th作为示踪剂的灰尘输入，和He同位素作为示踪剂的热液输入，我们将调查和量化的供应途径TE的SIO从大气，大陆（主要是赞比西河），沉积物（大陆斜坡），和海洋地壳（热液作用的印度洋脊）。该研究将基于FS索内号SO-276巡航期间收集的样本，该巡航定于2020年7月至8月在SIO从南非到澳大利亚。我们的调查将成为国际协调计划GEOTRACES的一部分，并将为第二次印度洋探险计划（IIOE-2）做出贡献。这项研究的结果将对了解生态系统运作的化学环境具有全球意义。