U.S. GEOTRACES Pacific Meridional Transect: Tracing Basin-scale Nutrient Cycling and Carbon Export with Dissolved and Particulate Barium-isotopic Distributions

美国 GEOTRACES 太平洋经线横断面：通过溶解和颗粒钡同位素分布追踪盆地规模的养分循环和碳输出

基本信息

批准号：
1736949
负责人：
Tristan Horner
金额：
$ 39.35万
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：
2018
资助国家：
美国
起止时间：
2018-01-01 至 2021-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1736949&HistoricalAwards=false
关键词：
U.S.GEOTRACES Pacific Meridional Transect

项目摘要

The goal of the international GEOTRACES program is to understand the distributions of trace chemical elements and their isotopes in the oceans. This project would measure stable isotopes of barium on a 2018 U.S. GEOTRACES expedition in the Pacific Ocean. Barium is a trace element whose distribution is relevant to all three themes of the GEOTRACES program, as barium can be used to: study chemical cycling within the oceans; trace exchanges of elements at ocean boundaries; and infer past environmental conditions. The data collected here will be the first of their kind for barium isotopes and will illuminate the geochemical cycle of this element. Moreover, conducting this work as part of the GEOTRACES program will maximize the return on investment in the barium isotope data by providing a rich interpretative framework.This project seeks to understand how the interplay between internal cycling and boundary processes sets basin-scale barium concentration and isotopic distributions in the Pacific Ocean. Despite possessing a nutrient-like dissolved profile, marine barium cycling has a fundamentally different boundary condition to the major algal nutrients: barium cycling is not driven by production of organic matter but rather by its remineralization. Respiration of sinking organic matter in the ocean's 'twilight zone' releases carbon dioxide, mineralizes nutrients, and promotes precipitation of micron-size crystals of barite. Since barite is the major vector of particulate barium in seawater, the abundance and isotopic composition of barium in the oceans is tied to global carbon and nutrient cycling at the 'dark end' of the biological carbon pump. The data collected here will be used to test hypotheses across an unprecedented range of oceanographic conditions regarding: the formation, export, and regeneration of particulate material and the connection to seafloor processes; the importance of boundary sources to regional and global trace element and isotope budgets; the formation of putative soft-metal sulfides in oxygen-minimum zones; and the origin of enigmatic suspended particles in the deep open ocean. This proposal will contribute to education by training undergraduate research fellows and through presentation of seminars and guest lectures to regional science educators through collaboration with a regional conservation organization.

国际 GEOTRACES 计划的目标是了解海洋中微量化学元素及其同位素的分布。该项目将在 2018 年美国 GEOTRACES 太平洋探险中测量钡的稳定同位素。钡是一种微量元素，其分布与 GEOTRACES 计划的所有三个主题相关，因为钡可用于：研究海洋内的化学循环；追踪海洋边界的元素交换；并推断过去的环境条件。这里收集的数据将是钡同位素同类数据中的第一个，并将阐明该元素的地球化学循环。此外，作为 GEOTRACES 计划的一部分进行这项工作将通过提供丰富的解释框架来最大限度地提高钡同位素数据的投资回报。该项目旨在了解内部循环和边界过程之间的相互作用如何确定盆地规模的钡浓度和太平洋的同位素分布。尽管具有类似营养物的溶解特征，但海洋钡循环与主要藻类营养物具有根本不同的边界条件：钡循环不是由有机物的产生驱动的，而是由其再矿化驱动的。海洋“暮光区”下沉有机物的呼吸作用释放二氧化碳，矿化营养物质，并促进微米级重晶石晶体的沉淀。由于重晶石是海水中颗粒钡的主要载体，因此海洋中钡的丰度和同位素组成与生物碳泵“暗端”的全球碳和营养物循环有关。这里收集的数据将用于测试前所未有的海洋条件下的假设：颗粒物质的形成、输出和再生以及与海底过程的联系；边界源对区域和全球微量元素和同位素预算的重要性；在含氧量最低的区域形成推定的软金属硫化物；以及深海中神秘悬浮颗粒的起源。该提案将通过培训本科研究员以及通过与地区保护组织合作向地区科学教育者举办研讨会和客座讲座来促进教育。

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Bioactive Trace Metals and Their Isotopes as Paleoproductivity Proxies: An Assessment Using GEOTRACES‐Era Data

生物活性微量金属及其同位素作为古生产力指标：使用 GEOTRACES Era 数据进行评估

DOI：
10.1002/essoar.10504252.1
发表时间：
2020-09-11
期刊：
Global Biogeochemical Cycles
影响因子：
5.2
作者：
T. Horner;S. Little;T. Conway;J. Farmer;J. Hertzberg;D. J. Janssen;A.J.M. Lough;J. McKay;A. Tessin;S. Galer;S. Jaccard;F. Lacan;A. Paytan;K. Wuttig;GEOTRACES–PAGES Biological Producti Members
通讯作者：
GEOTRACES–PAGES Biological Producti Members

A decade of progress in understanding cycles of trace elements and their isotopes in the oceans

了解海洋中微量元素及其同位素循环的十年进展

DOI：
10.1016/j.chemgeo.2021.120381
发表时间：
2021-10-05
期刊：
Chemical Geology
影响因子：
3.9
作者：
T. Conway;T. Horner;Y. Plancherel;Aridane G. González
通讯作者：
Aridane G. González

A spatially and vertically resolved global grid of dissolved barium concentrations in seawater determined using Gaussian Process Regression machine learning

使用高斯过程回归机器学习确定海水中溶解钡浓度的空间和垂直解析全局网格

DOI：
10.26008/1912/bco-dmo.885506.2
发表时间：
2023-01
期刊：
Biological and Chemical Oceanography Data Management Office (BCO-DMO
影响因子：
0
作者：
Horner, Tristan J.;Mete, Oyku Z.
通讯作者：
Mete, Oyku Z.

Barium in deep-sea bamboo corals: Phase associations, barium stable isotopes, & prospects for paleoceanography

深海竹珊瑚中的钡：相关联、钡稳定同位素、

DOI：
10.1016/j.epsl.2019.115751
发表时间：
2019-11
期刊：
Earth and Planetary Science Letters
影响因子：
5.3
作者：
Geyman, Ben M.;Ptacek, Jamie L.;LaVigne, Michèle;Horner, Tristan J.
通讯作者：
Horner, Tristan J.

Barium in seawater: dissolved distribution, relationship to silicon, and barite saturation state determined using machine learning

海水中的钡：溶解分布、与硅的关系以及使用机器学习确定的重晶石饱和状态

DOI：
10.5194/essd-15-4023-2023
发表时间：
2023-09-13
期刊：
Earth System Science Data
影响因子：
11.4
作者：
Öykü Z. Mete;A. Subhas;Heather H. Kim;A. Dunlea;L. Whitmore;A. Shiller;Melissa Gilbert;William D. Leavitt;Tristan J. Horner
通讯作者：
Tristan J. Horner