气候变化领域集成服务门户(CCPortal): The Spatial and Temporal Variability of Mn Speciation in the Coastal Northwest Atlantic Ocean

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DOI	10.1029/2019JC015167
	The Spatial and Temporal Variability of Mn Speciation in the Coastal Northwest Atlantic Ocean
	Oldham V.E.; Lamborg C.H.; Hansel C.M.
发表日期	2020
ISSN	21699275
卷号	125 期号:1
英文摘要	Manganese (Mn) is distributed widely throughout the global ocean, where it cycles between three oxidation states that each play important biogeochemical roles. The speciation of Mn in seawater was previously operationally defined on filtration, with soluble Mn presumed to be Mn(II) and solid-phase Mn as Mn(III/IV) oxides. Recent findings of abundant soluble Mn(III) complexes (Mn(III)-L) highlights the need to reexamine the redox cycling of Mn, as these complexes can donate or accept electrons. To better understand the complex cycling of Mn in coastal waters, the distribution of Mn species at four Northwest Atlantic sites with different characteristics was examined. Diurnal influences on Mn speciation were investigated within a productive site. At all sites, Mn(III)-L complexes dominated, particularly in surface waters, and Mn oxides were low in abundance in surface waters but high in bottom waters. Despite intrasite similarities, Mn speciation was highly variable between our stations, emphasizing the diverse processes that impact Mn redox. Diel Mn measurements revealed that the cycling of Mn is also highly variable over time, even on time scales as short as hours. We observed a change of over 100 nM total Mn over 17 hrs and find that speciation changed drastically. These changes could include contributions from biological, light-mediated, and/or abiotic mechanisms but more likely point to the importance of lateral mixing at coastal sites. This exploration demonstrates the spatial and temporal variability of the Mn redox cycle and indicates that single timepoint vertical profiling is not sufficient when describing the geochemistry of dynamic coastal systems. ©2019. American Geophysical Union. All Rights Reserved.
英文关键词	Coastal Ocean; Diel Cycle; Manganese; Organic Complexation; Redox; Trace Metal
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187037
作者单位	Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, United States; Department of Ocean Sciences, University of California, Santa Cruz, CA, United States; Now at Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, United States
推荐引用方式 GB/T 7714	Oldham V.E.,Lamborg C.H.,Hansel C.M.. The Spatial and Temporal Variability of Mn Speciation in the Coastal Northwest Atlantic Ocean[J],2020,125(1).
APA	Oldham V.E.,Lamborg C.H.,&Hansel C.M..(2020).The Spatial and Temporal Variability of Mn Speciation in the Coastal Northwest Atlantic Ocean.Journal of Geophysical Research: Oceans,125(1).
MLA	Oldham V.E.,et al."The Spatial and Temporal Variability of Mn Speciation in the Coastal Northwest Atlantic Ocean".Journal of Geophysical Research: Oceans 125.1(2020).