Nitrogen Isotope and N2/Ar Biogeochemistry of the Peru Suboxic Zone

秘鲁低氧带的氮同位素和 N2/Ar 生物地球化学

• 批准号: 0851092
• 负责人: Mark Altabet
• 金额: $ 39.29万
• 依托单位: University of Massachusetts, Dartmouth
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-02-01 至 2013-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0851092&HistoricalAwards=false
• 关键词: Nitrogen; Isotope; N2; Ar; Biogeochemistry

The suboxic intermediate waters of the world's oceans, though constituting only a small fraction of total oceanic volume (0.1%), play a vital role in the ocean's nitrogen cycle and its biogeochemical and isotopic signatures. Suboxic conditions are required to activate the microbial processes that convert nitrogen to N2 gas. Because of this, suboxic waters act as a predominant sink, removing nitrogen from the biosphere. An ocean chemist from the University of Massachusetts at Dartmouth is working in collaboration with scientists from GEOMAR/Kiel University to complete an extensive field study of the Eastern Tropical South Pacific Ocean off the coast of Peru, one of the three major open ocean suboxic zones. Water samples, collected from a series of transects off the Peruvian margin, would undergo isotopic and gas ratio analyses to assess the following: (1) insights on the net impact of the Peru suboxic zone on oceanic nitrogen and nitrogen isotope budgets and (2) the relationship between the intensity of the nitrogen sink and the nitrogen isotope signal preserved in margin sediments. Results from this research would provide the science community with a greater understanding of the relationship between the oceanic nitrogen cycle and suboxic waters. As regards broader impacts, this research would refine the interpretation of paleo-records with respect to past interactions between the oceanic nitrogen cycle and climate variability and contribute to numerical modeling studies of the global oceanic cycle. This study represents a collaborative effort between U.S., German, and Peruvian scientists. One graduate student would be supported and trained as part of this project.

世界海洋的亚氧化中间水域虽然仅占总海洋量的一小部分（0.1％），但在海洋的氮循环及其生物地球化学和同位素特征中起着至关重要的作用。需要亚氧化条件来激活将氮转化为N2气体的微生物过程。因此，亚氧化水充当了主要的水槽，从生物圈中去除氮。马萨诸塞大学达特茅斯大学的一名海洋化学家正在与Geomar/Kiel大学的科学家合作，完成对秘鲁海岸东部热带南太平洋的广泛实地研究，这是三个主要的开阔海洋亚氧化区之一。 Water samples, collected from a series of transects off the Peruvian margin, would undergo isotopic and gas ratio analyses to assess the following: (1) insights on the net impact of the Peru suboxic zone on oceanic nitrogen and nitrogen isotope budgets and (2) the relationship between the intensity of the nitrogen sink and the nitrogen isotope signal preserved in margin sediments. 这项研究的结果将使科学界对海洋氮周期和亚氧化水之间的关系有更深入的了解。关于更广泛的影响，这项研究将完善对海洋氮循环与气候变化之间过去相互作用的古录制的解释，并有助于全球海洋周期的数值建模研究。 这项研究代表了美国，德国和秘鲁科学家之间的合作努力。 作为该项目的一部分，将为一名研究生提供支持和培训。