气候变化领域集成服务门户(CCPortal): Iron Distribution in the Subtropical North Atlantic: The Pivotal Role of Colloidal Iron

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DOI	10.1029/2019GB006326
	Iron Distribution in the Subtropical North Atlantic: The Pivotal Role of Colloidal Iron
	Kunde K.; Wyatt N.J.; González-Santana D.; Tagliabue A.; Mahaffey C.; Lohan M.C.
发表日期	2019
ISSN	0886-6236
EISSN	1944-9224
起始页码	1532
结束页码	1547
卷号	33 期号:12
英文摘要	The low availability of the essential micronutrient iron (Fe) in the ocean impacts the efficiency of the biological carbon pump, and hence, it is vital to elucidate its sources, sinks, and internal cycling. We present size-fractionated dissolved Fe (dFe, <0.2 μm) measurements from 130 surface samples and 7 full-depth profiles from the subtropical North Atlantic during summer 2017 and demonstrate the pivotal role of colloidal (cFe, 0.02 to 0.2 μm) over soluble (sFe, <0.02 μm) Fe in controlling the dFe distribution. In the surface (<5 m), a strong west-to-east decrease in dFe (1.53 to 0.26 nM) was driven by a dust gradient, which retained dFe predominantly as cFe (61% to 85% of dFe), while sFe remained largely constant at 0.19 ± 0.05 nM. In the euphotic zone, the attenuation of dFe resulted from the depletion of cFe (0% to 30% of dFe), with scavenging as an important driver. In the mesopelagic, cFe was released from sinking biogenic and lithogenic particles, creating a zone of elevated dFe (0.7 to 1.0 nM) between 400 to 1100 m depth. While the ocean interior, below the mesopelagic and above the seafloor boundary, exhibited a narrow range of cFe (40% to 60% of dFe), the abyssal cFe fraction varied in range from 26% to 76% due to interactions with seafloor sediments and a hydrothermal source with almost 100% cFe. Overall, our results produced an hourglass shape for the vertical cFe-to-dFe fraction and highlight the primary control of cFe on the dFe distribution. ©2019. American Geophysical Union. All Rights Reserved.
英文关键词	colloidal iron; dissolved iron; GEOTRACES; subtropical North Atlantic
语种	英语
scopus关键词	biogeochemistry; biological pump; colloid; dissolved inorganic matter; eolian deposit; iron; source-sink dynamics; subtropical region; tracer; Atlantic Ocean; Atlantic Ocean (North)
来源期刊	Global Biogeochemical Cycles
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/129693
作者单位	Ocean and Earth Sciences, National Oceanography Centre, University of Southampton, Southampton, United Kingdom; Department of Earth, Ocean, and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
推荐引用方式 GB/T 7714	Kunde K.,Wyatt N.J.,González-Santana D.,et al. Iron Distribution in the Subtropical North Atlantic: The Pivotal Role of Colloidal Iron[J],2019,33(12).
APA	Kunde K.,Wyatt N.J.,González-Santana D.,Tagliabue A.,Mahaffey C.,&Lohan M.C..(2019).Iron Distribution in the Subtropical North Atlantic: The Pivotal Role of Colloidal Iron.Global Biogeochemical Cycles,33(12).
MLA	Kunde K.,et al."Iron Distribution in the Subtropical North Atlantic: The Pivotal Role of Colloidal Iron".Global Biogeochemical Cycles 33.12(2019).