{"title":"通过数据约束模型更好地了解全球海洋铜的分布和形态","authors":"Hengdi Liang, James W. Moffett, Seth G. John","doi":"10.1029/2023GB007769","DOIUrl":null,"url":null,"abstract":"<p>Copper (Cu) is an important micronutrient for marine organisms, which can also be toxic at elevated concentrations. Here, we present a new model of global ocean Cu biogeochemical cycling, constrained by GEOTRACES observations, with key processes including sources from rivers, dust, and sediments, biological uptake and remineralization of Cu, reversible scavenging of Cu onto sinking particles, conversion of Cu between labile and inert species, and ocean circulation. In order for the model to match observations, in particular the relatively small increase in Cu concentrations along the global “conveyor belt,” we find it is necessary to include significant external sources of Cu with a magnitude of roughly 1.3 Gmol yr<sup>−1</sup>, having a relatively stronger impact on the Atlantic Ocean, though the relative contributions of river, dust, and sediment sources are poorly constrained. The observed nearly linear increase in Cu concentrations with depth requires a strong benthic source of Cu, which includes the sedimentary release of Cu that was reversibly scavenged from the water column. The processes controlling Cu cycling in the Arctic Ocean appear to be unique, requiring both relatively high Cu concentrations in Arctic rivers and reduced scavenging in the Arctic. Observed partitioning of Cu between labile and inert phases is reproduced in the model by the slow conversion of labile Cu to inert in the whole water column with a half-life of ∼250 years, and the photodegradation of inert Cu to labile in the surface ocean with a minimum half-life of ∼2 years at the equator.</p>","PeriodicalId":12729,"journal":{"name":"Global Biogeochemical Cycles","volume":null,"pages":null},"PeriodicalIF":5.4000,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023GB007769","citationCount":"0","resultStr":"{\"title\":\"Toward a Better Understanding of the Global Ocean Copper Distribution and Speciation Through a Data-Constrained Model\",\"authors\":\"Hengdi Liang, James W. Moffett, Seth G. John\",\"doi\":\"10.1029/2023GB007769\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>Copper (Cu) is an important micronutrient for marine organisms, which can also be toxic at elevated concentrations. Here, we present a new model of global ocean Cu biogeochemical cycling, constrained by GEOTRACES observations, with key processes including sources from rivers, dust, and sediments, biological uptake and remineralization of Cu, reversible scavenging of Cu onto sinking particles, conversion of Cu between labile and inert species, and ocean circulation. In order for the model to match observations, in particular the relatively small increase in Cu concentrations along the global “conveyor belt,” we find it is necessary to include significant external sources of Cu with a magnitude of roughly 1.3 Gmol yr<sup>−1</sup>, having a relatively stronger impact on the Atlantic Ocean, though the relative contributions of river, dust, and sediment sources are poorly constrained. The observed nearly linear increase in Cu concentrations with depth requires a strong benthic source of Cu, which includes the sedimentary release of Cu that was reversibly scavenged from the water column. The processes controlling Cu cycling in the Arctic Ocean appear to be unique, requiring both relatively high Cu concentrations in Arctic rivers and reduced scavenging in the Arctic. Observed partitioning of Cu between labile and inert phases is reproduced in the model by the slow conversion of labile Cu to inert in the whole water column with a half-life of ∼250 years, and the photodegradation of inert Cu to labile in the surface ocean with a minimum half-life of ∼2 years at the equator.</p>\",\"PeriodicalId\":12729,\"journal\":{\"name\":\"Global Biogeochemical Cycles\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":5.4000,\"publicationDate\":\"2023-08-30\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023GB007769\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Global Biogeochemical Cycles\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1029/2023GB007769\",\"RegionNum\":2,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENVIRONMENTAL SCIENCES\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Global Biogeochemical Cycles","FirstCategoryId":"89","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1029/2023GB007769","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
Toward a Better Understanding of the Global Ocean Copper Distribution and Speciation Through a Data-Constrained Model
Copper (Cu) is an important micronutrient for marine organisms, which can also be toxic at elevated concentrations. Here, we present a new model of global ocean Cu biogeochemical cycling, constrained by GEOTRACES observations, with key processes including sources from rivers, dust, and sediments, biological uptake and remineralization of Cu, reversible scavenging of Cu onto sinking particles, conversion of Cu between labile and inert species, and ocean circulation. In order for the model to match observations, in particular the relatively small increase in Cu concentrations along the global “conveyor belt,” we find it is necessary to include significant external sources of Cu with a magnitude of roughly 1.3 Gmol yr−1, having a relatively stronger impact on the Atlantic Ocean, though the relative contributions of river, dust, and sediment sources are poorly constrained. The observed nearly linear increase in Cu concentrations with depth requires a strong benthic source of Cu, which includes the sedimentary release of Cu that was reversibly scavenged from the water column. The processes controlling Cu cycling in the Arctic Ocean appear to be unique, requiring both relatively high Cu concentrations in Arctic rivers and reduced scavenging in the Arctic. Observed partitioning of Cu between labile and inert phases is reproduced in the model by the slow conversion of labile Cu to inert in the whole water column with a half-life of ∼250 years, and the photodegradation of inert Cu to labile in the surface ocean with a minimum half-life of ∼2 years at the equator.
期刊介绍:
Global Biogeochemical Cycles (GBC) features research on regional to global biogeochemical interactions, as well as more local studies that demonstrate fundamental implications for biogeochemical processing at regional or global scales. Published papers draw on a wide array of methods and knowledge and extend in time from the deep geologic past to recent historical and potential future interactions. This broad scope includes studies that elucidate human activities as interactive components of biogeochemical cycles and physical Earth Systems including climate. Authors are required to make their work accessible to a broad interdisciplinary range of scientists.