{"title":"根据汞同位素确定西北太平洋颗粒结合汞的来源","authors":"Shuyuan Huang, Yunlong Huo, Heng Sun, Supeng Lv, Yuhan Zhao, Kunning Lin, Yaojin Chen and Yuanbiao Zhang*, ","doi":"10.1021/acsearthspacechem.3c0036510.1021/acsearthspacechem.3c00365","DOIUrl":null,"url":null,"abstract":"<p >Atmospheric mercury (Hg) transport and transformation controls the global Hg budget. Of which, the particulate-bound mercury (PBM) sources and subsequent deposition are crucial, especially in the open ocean. Here, we present the first Hg isotope compositions of PBM in the Northwest Pacific during three cruises from 2018 to 2019. The PBM samples were less influenced by long-range transport of anthropogenic emissions according to the low PBM concentrations (19.7 ± 10.9, <i>n</i> = 52, 1SD). The mass-independent fractionation signatures are mainly controlled by photochemical reactions as the ratio of Δ<sup>199</sup>Hg/Δ<sup>201</sup>Hg was close to 1.0. The <i>in situ</i> Hg oxidation of Br radicals plays an important role in keeping PBM Δ<sup>200</sup>Hg values lower, while the background atmospheric Hg(II) pool, which is derived from Hg oxidation by O<sub>2</sub> in the free troposphere, provides highly positive Δ<sup>200</sup>Hg values for PBM. The common photoredox reactions and subsequent adsorption adjust the PBM isotopic composition within a moderate range. We used an isotope mixing model to estimate the contributions of each factor. Compared with PBM in other areas (e.g., urban, high-altitude), contributions from photochemical oxidation increased in the marine boundary layer of the open ocean. The results of this study have improved our understanding of the transport pathways of PBM in the atmosphere and highlighted the important use of Hg isotopes in process analysis and source tracing.</p>","PeriodicalId":15,"journal":{"name":"ACS Earth and Space Chemistry","volume":null,"pages":null},"PeriodicalIF":2.9000,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Sources of Particulate Bound Mercury in the Northwest Pacific Constrained by Hg Isotopes\",\"authors\":\"Shuyuan Huang, Yunlong Huo, Heng Sun, Supeng Lv, Yuhan Zhao, Kunning Lin, Yaojin Chen and Yuanbiao Zhang*, \",\"doi\":\"10.1021/acsearthspacechem.3c0036510.1021/acsearthspacechem.3c00365\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >Atmospheric mercury (Hg) transport and transformation controls the global Hg budget. Of which, the particulate-bound mercury (PBM) sources and subsequent deposition are crucial, especially in the open ocean. Here, we present the first Hg isotope compositions of PBM in the Northwest Pacific during three cruises from 2018 to 2019. The PBM samples were less influenced by long-range transport of anthropogenic emissions according to the low PBM concentrations (19.7 ± 10.9, <i>n</i> = 52, 1SD). The mass-independent fractionation signatures are mainly controlled by photochemical reactions as the ratio of Δ<sup>199</sup>Hg/Δ<sup>201</sup>Hg was close to 1.0. The <i>in situ</i> Hg oxidation of Br radicals plays an important role in keeping PBM Δ<sup>200</sup>Hg values lower, while the background atmospheric Hg(II) pool, which is derived from Hg oxidation by O<sub>2</sub> in the free troposphere, provides highly positive Δ<sup>200</sup>Hg values for PBM. The common photoredox reactions and subsequent adsorption adjust the PBM isotopic composition within a moderate range. We used an isotope mixing model to estimate the contributions of each factor. Compared with PBM in other areas (e.g., urban, high-altitude), contributions from photochemical oxidation increased in the marine boundary layer of the open ocean. The results of this study have improved our understanding of the transport pathways of PBM in the atmosphere and highlighted the important use of Hg isotopes in process analysis and source tracing.</p>\",\"PeriodicalId\":15,\"journal\":{\"name\":\"ACS Earth and Space Chemistry\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":2.9000,\"publicationDate\":\"2024-07-12\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"ACS Earth and Space Chemistry\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://pubs.acs.org/doi/10.1021/acsearthspacechem.3c00365\",\"RegionNum\":3,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"CHEMISTRY, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Earth and Space Chemistry","FirstCategoryId":"92","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acsearthspacechem.3c00365","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
Sources of Particulate Bound Mercury in the Northwest Pacific Constrained by Hg Isotopes
Atmospheric mercury (Hg) transport and transformation controls the global Hg budget. Of which, the particulate-bound mercury (PBM) sources and subsequent deposition are crucial, especially in the open ocean. Here, we present the first Hg isotope compositions of PBM in the Northwest Pacific during three cruises from 2018 to 2019. The PBM samples were less influenced by long-range transport of anthropogenic emissions according to the low PBM concentrations (19.7 ± 10.9, n = 52, 1SD). The mass-independent fractionation signatures are mainly controlled by photochemical reactions as the ratio of Δ199Hg/Δ201Hg was close to 1.0. The in situ Hg oxidation of Br radicals plays an important role in keeping PBM Δ200Hg values lower, while the background atmospheric Hg(II) pool, which is derived from Hg oxidation by O2 in the free troposphere, provides highly positive Δ200Hg values for PBM. The common photoredox reactions and subsequent adsorption adjust the PBM isotopic composition within a moderate range. We used an isotope mixing model to estimate the contributions of each factor. Compared with PBM in other areas (e.g., urban, high-altitude), contributions from photochemical oxidation increased in the marine boundary layer of the open ocean. The results of this study have improved our understanding of the transport pathways of PBM in the atmosphere and highlighted the important use of Hg isotopes in process analysis and source tracing.
期刊介绍:
The scope of ACS Earth and Space Chemistry includes the application of analytical, experimental and theoretical chemistry to investigate research questions relevant to the Earth and Space. The journal encompasses the highly interdisciplinary nature of research in this area, while emphasizing chemistry and chemical research tools as the unifying theme. The journal publishes broadly in the domains of high- and low-temperature geochemistry, atmospheric chemistry, marine chemistry, planetary chemistry, astrochemistry, and analytical geochemistry. ACS Earth and Space Chemistry publishes Articles, Letters, Reviews, and Features to provide flexible formats to readily communicate all aspects of research in these fields.