Sharpening Geochemical Tools for Assessing Oceanic Biological Production: Exploring the Limits of Oxygen/Argon Ratios and Triple Oxygen Isotopes

改进评估海洋生物生产的地球化学工具：探索氧/氩比和三氧同位素的极限

• 批准号: 1029676
• 负责人: Rachel Stanley
• 金额: $ 39.29万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1029676&HistoricalAwards=false
• 关键词: Sharpening; Geochemical; Tools; Assessing; Oceanic

Net community production (NCP) and gross primary production (GPP) are two key processes in the marine carbon cycle which can be quantified in situ using triple oxygen isotopes (TOI) and continuous measurements of O2/Ar. Unfortunately, two key issues involved with measuring and interpreting TOI and O2/Ar data remain unresolved, namely, measurement uncertainty and spatial variability. A scientist from Woods Hole Oceanographic Institution plans to carry out an intercalibration effort between eight laboratories worldwide to address whether differences in TOI signatures observed between sample sites are results of real differences in the oceanic isotopic signature of oxygen or whether they are measurement artifacts. As part of the intercalibration, a suite of gas, homogenized water, equilibrated water, and seawater samples will be distributed to the laboratories to assess each step of the measurement process. In addition, the researcher will participate in a cruise of opportunity to examine the spatial variability in TOI and O2/Ar ratios and to determine the causes for this variability. To accomplish this goal, several grid surveys of continuous surface ocean O2/Ar measurements from an equilibrator inlet mass spectrometer (EIMS) and high resolution TOI sampling will be conducted. A video plankton recorder (VPR-II) will be towed on the cruise to continuously measure profiles of O2, plankton and seston abundance, temperature, salinity, fluorescence, photosynthetically available radiation, and turbidity in the upper 150 m of the water column. Various statistical estimators (co-spectra, wavelets, probability density functions) will be used to investigate linkages between hydrographic properties, biogeochemical properties, O2/Ar ratios, and TOI. This work, which will be the first to combine an EIMS and the VPR-II, will quantify spatial variability on scales from two to one thousand kilometers.As regards broader Impacts, as a result of this intercalibration effort, tried and tested biogeochemical tracers for determining in situ gross primary productivity and net carbon productivity would be available to the marine sciences community. One graduate student would be supported and trained as part of this project.

净群落生产 (NCP) 和总初级生产 (GPP) 是海洋碳循环中的两个关键过程，可以使用三氧同位素 (TOI) 和连续测量 O2/Ar 进行原位量化。 不幸的是，测量和解释 TOI 和 O2/Ar 数据涉及的两个关键问题仍未解决，即测量不确定性和空间变异性。 伍兹霍尔海洋研究所的一位科学家计划在全球八个实验室之间进行相互校准工作，以确定采样点之间观察到的 TOI 特征差异是否是海洋氧同位素特征差异的真实结果，或者它们是否是测量伪影。 作为相互校准的一部分，一套气体、均质水、平衡水和海水样品将被分发到实验室，以评估测量过程的每个步骤。 此外，研究人员还将参与一系列机会检查 TOI 和 O2/Ar 比率的空间变异性，并确定这种变异性的原因。 为了实现这一目标，将通过平衡器入口质谱仪 (EIMS) 和高分辨率 TOI 采样对连续表面海洋 O2/Ar 测量进行多次网格调查。 游轮上将拖曳浮游生物视频记录仪（VPR-II），连续测量水柱上部 150 m 的 O2、浮游生物和浮游生物丰度、温度、盐度、荧光、光合有效辐射和浊度。 各种统计估计器（共谱、小波、概率密度函数）将用于研究水文学特性、生物地球化学特性、O2/Ar 比率和 TOI 之间的联系。 这项工作将是第一个将 EIMS 和 VPR-II 结合起来的工作，它将量化 2 到 1000 公里尺度的空间变异性。 至于更广泛的影响，由于这种相互校准工作，海洋科学界将可以使用经过尝试和测试的生物地球化学示踪剂来确定原位总初级生产力和净碳生产力。 作为该项目的一部分，一名研究生将得到支持和培训。