Collaborative Proposal: Unravelling the Oceanic Dimethylmercury Cycle

合作提案：揭示海洋二甲基汞循环

基本信息

批准号：
2023031
负责人：
Carl Lamborg
金额：
$ 29.29万
依托单位：
University of California-Santa Cruz
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2023031&HistoricalAwards=false
关键词：
Collaborative Proposal Unravelling Oceanic Dimethylmercury

项目摘要

Collaborative Proposal: Unravelling the Oceanic Dimethylmercury CycleThis project will study how dimethylmercury is formed and removed in the oceans. Dimethylmercury is a naturally occurring compound. It is thought to be formed when man-made mercury is converted into monomethylmercury, a toxin that accumulates in fish. Despite representing a large fraction of mercury in the oceans, the origin and fate of dimethylmercury is not known. This research will use state-of-the-art analytical, genomic and modeling tools to address this information gap. It will also train graduate and undergraduate students to use field, experimental, and modeling methods. The results will be used in predictive models to forecast future trends in the oceanic mercury cycle. These models are needed to evaluate the effectiveness of international actions that seek to reverse increasing trends in the bioaccumulation of monomethylmercury in fish. Methylated mercury species in the ocean are formed in sediment and the water column from inorganic divalent mercury delivered from the atmosphere and rivers. The putative mechanism is a two-step process during which monomethylmercury is formed first, followed by slow methylation into dimethylmercury. The first step, biomethylation of divalent mercury into monomethylmercury, is relatively well-studied in sediment and known to be driven by sulfate- and iron-reducing bacteria and methanogens. The mechanism for monomethylmercury formation in the water column is less well understood, and the process of dimethylmercury formation in sediment or seawater is essentially unknown. Until recently, it was assumed that dimethylmercury represented a small enough fraction of the methylated and total mercury (the sum of all mercury species) pools to be insignificant in the global mercury cycle. Recent measurements, however, show that dimethylmercury levels in seawater can be in the same range as the other mercury species. This project will identify the biological and chemical methylating agents involved in the formation of dimethylmercury. Further, it will test the impact of varying biogeochemical conditions on dimethylmercury production. Results will be used to update the mercury module of the MIT General Circulation Model (MITgcm, a global biogeochemical model, and analyze the impacts of dimethylmercury production and degradation on monomethylmercury concentrations.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

合作提案：揭示海洋二甲基汞循环该项目将研究二甲基汞如何在海洋中形成和去除。二甲基汞是一种天然存在的化合物。人们认为，人造汞转化为单甲基汞（一种在鱼体内积聚的毒素）时就会形成。尽管二甲基汞占海洋中汞的很大一部分，但二甲基汞的起源和命运尚不清楚。这项研究将使用最先进的分析、基因组和建模工具来解决这一信息差距。它还将培训研究生和本科生使用现场、实验和建模方法。研究结果将用于预测模型，以预测海洋汞循环的未来趋势。需要这些模型来评估旨在扭转鱼类单甲基汞生物累积不断增长趋势的国际行动的有效性。海洋中的甲基化汞物种是由大气和河流输送的无机二价汞在沉积物和水柱中形成的。假定的机制是一个两步过程，首先形成单甲基汞，然后缓慢甲基化为二甲基汞。第一步是将二价汞生物甲基化为一甲基汞，这一过程在沉积物中得到了相对充分的研究，并且已知是由硫酸盐和铁还原菌以及产甲烷菌驱动的。人们对水柱中一甲基汞形成的机制知之甚少，而沉积物或海水中二甲基汞形成的过程基本上也是未知的。直到最近，人们还认为二甲基汞在甲基化汞和总汞（所有汞种类的总和）库中所占的比例足够小，在全球汞循环中微不足道。然而，最近的测量表明，海水中二甲基汞的含量可能与其他汞种类处于同一范围内。该项目将鉴定参与二甲基汞形成的生物和化学甲基化剂。此外，它将测试不同的生物地球化学条件对二甲基汞生产的影响。结果将用于更新麻省理工学院大气循环模型（MITgcm，一个全球生物地球化学模型）的汞模块，并分析二甲基汞的产生和降解对单甲基汞浓度的影响。该奖项反映了 NSF 的法定使命，并被认为值得通过以下方式支持：使用基金会的智力价值和更广泛的影响审查标准进行评估。

项目成果

期刊论文数量（5）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

The Effect of Particle Composition and Concentration on the Partitioning Coefficient for Mercury in Three Ocean Basins

三个洋盆中颗粒组成和浓度对汞分配系数的影响

DOI：
10.3389/fenvc.2021.660267
发表时间：
2021-05
期刊：
Frontiers in Environmental Chemistry
影响因子：
0
作者：
Cui, Xinyun;Lamborg, Carl H.;Hammerschmidt, Chad R.;Xiang, Yang;Lam, Phoebe J.
通讯作者：
Lam, Phoebe J.

Hydrothermal trace metal release and microbial metabolism in the northeastern Lau Basin of the South Pacific Ocean

南太平洋劳盆地东北部热液微量金属释放和微生物代谢

DOI：
10.5194/bg-18-5397-2021
发表时间：
2021-01
期刊：
Biogeosciences
影响因子：
4.9
作者：
Cohen, Natalie R.;Noble, Abigail E.;Moran, Dawn M.;McIlvin, Matthew R.;Goepfert, Tyler J.;Hawco, Nicholas J.;German, Christopher R.;Horner, Tristan J.;Lamborg, Carl H.;McCrow, John P.;et al
通讯作者：
et al

Large subglacial source of mercury from the southwestern margin of the Greenland Ice Sheet

DOI：
10.1038/s41561-021-00753-w
发表时间：
2021-05-24
期刊：
Nature Geoscience
影响因子：
18.3
作者：
J. Hawkings;B. Linhoff;J. Wadham;M. Stibal;C. Lamborg;G. Carling;G. Lamarche;T. Kohler;R. Ward;K. Hendry;L. Falteisek;A. Kellerman;Karen A. Cameron;J. Hatton;S. Tingey;Amy D. Holt;P. Vinšová;Stefan Hofer;Marie Bulínová;T. Větrovský;L. Meire;R. Spencer
通讯作者：
R. Spencer

Mercury methylation by metabolically versatile and cosmopolitan marine bacteria

DOI：
10.1038/s41396-020-00889-4
发表时间：
2021-06
期刊：
The ISME Journal
影响因子：
0
作者：
Lin H;Ascher DB;Myung Y;Lamborg CH;Hallam SJ;Gionfriddo CM;Holt KE;Moreau JW
通讯作者：
Moreau JW

Bluefin tuna reveal global patterns of mercury pollution and bioavailability in the world's oceans

蓝鳍金枪鱼揭示了全球海洋汞污染和生物利用度的模式