Nitrous oxide cycling in the Western Arctic Ocean from stable isotopic and concentration data

根据稳定同位素和浓度数据了解北冰洋西部的一氧化二氮循环

• 批准号: 1927755
• 负责人: Annie Bourbonnais
• 金额: $ 11.67万
• 依托单位: University of South Carolina at Columbia
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-11-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1927755&HistoricalAwards=false
• 关键词: Nitrous; oxide; cycling; Western; Arctic

Nitrous oxide is a potent greenhouse gas in the troposphere and an ozone-depleting substance in the stratosphere, yet its sources and sinks in the ocean are neither well-quantified nor well understood. Nitrous oxide is both produced and consumed by microbial processes; it is produced by different processes dependent upon the amount of oxygen present locally. The Arctic Ocean may represent an important source of nitrous oxide to the atmosphere. High nitrous oxide saturations were recently observed in productive shallow Arctic shelf waters. The proposed research will test the hypotheses that productive shelf regions of the Western Arctic Ocean (e.g., Chukchi and Beaufort seas) stimulates nitrous oxide production and contributes to offshore transport of nitrous oxide toward the central Arctic. Besides developing an important baseline data set for the Arctic science community, this project will contribute to STEM workforce development in numerous manners. It will support an early-career female scientist during the formative years of her career. It will provide summer educational research opportunities to undergraduate students. It will develop seminars for elementary school teachers and provide short classroom presentations at a local public school and contribute to an afterschool non-profit effort devoted to providing high quality educational programs to at risk youth.The primary goal of this proposed research is to evaluate nitrous oxide cycling in the Western Arctic Ocean from its concentrations, stable isotopes and isotopomers. The project will use isotopic and isotopomer measurements from both shelf and offshore waters to constrain estimates of nitrous oxide cycling in the Arctic. The data will be used to evaluate 1) the pathways of nitrous oxide production from either nitrification following organic matter decomposition in the water column or coupled nitrification-denitrification in the sediments and 2) how these processes influence nitrous oxide exchanges between the surface layer and the atmosphere. Comparisons of observations at coastal and shelf stations in the Bering and Chukchi seas with those offshore in the Deep Canadian Basin will allow the evaluation of the effects of mixing and long-range transport on geochemical signals. The measurements will also serve as a baseline for future assessment of change. The project profits from leveraging of other investments by NSF and the principal investigators? international collaborators, benefitting from measurements and samples collected during the U.S. GEOTRACES Arctic section and the 2016 CHINARE Arctic cruises.

一氧化二氮是对流层中有效的温室气体，是平流层中的臭氧动物，但其在海洋中的来源和下沉既不是充分的，也没有充分理解。一氧化二氮是由微生物过程产生和消耗的。它是由不同的过程取决于局部存在的氧气量产生的。北极海可能代表了大气中一氧化二氮的重要来源。最近在生产性浅北北货架水中观察到了高一氧化二氮饱和度。拟议的研究将检验以下假设，即西方北极海洋的生产货架区域（例如Chukchi和Beaufort）刺激一氧化二氮的产生，并有助于将一氧化氮向中央北极地区运输。除了为北极科学界开发重要的基线数据集外，该项目还将以多种方式为STEM劳动力发展做出贡献。 它将在她职业生涯的成长时期支持一位早期的女性科学家。 它将为本科生提供夏季的教育研究机会。 It will develop seminars for elementary school teachers and provide short classroom presentations at a local public school and contribute to an afterschool non-profit effort devoted to providing high quality educational programs to at risk youth.The primary goal of this proposed research is to evaluate nitrous oxide cycling in the Western Arctic Ocean from its concentrations, stable isotopes and isotopomers.该项目将使用架子和近海水域的同位素和同位素测量值来约束北极一氧化二氮循环的估计。该数据将用于评估1）在水柱中有机物分解后硝化二氮产生的途径，或在沉积物中偶联的硝化硝化途径，以及2）这些过程如何影响一硝酸氧化物在表面层和大气之间的交换。比较白令和丘奇海中沿海和货架站的观察结果与加拿大深层盆地的海上观察站的比较，将允许评估混合和长距离运输对地球化学信号的影响。这些测量还将作为对变革的未来评估的基准。 NSF和主要研究人员利用其他投资的项目利润？国际合作者受益于在美国地理区域北极地区和2016年Chinare北极巡游中收集的测量和样本。