DOI: 10.1002/gbc.20076
Scopus记录号: 2-s2.0-84883173666
论文题名: Post-depositional processes: What really happens to new atmospheric iron in the ocean's surface?
作者: Bressac M ; , Guieu C
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2013
卷: 27, 期: 3 起始页码: 859
结束页码: 870
语种: 英语
英文关键词: adsorption
; aggregation
; atmospheric dissolved iron
; dissolved organic matter
; scavenging
Scopus关键词: Artificial seeding
; Biogeochemical conditions
; Biological response
; Dissolved iron
; Dissolved organic matters
; Iron distribution
; Settling particles
; Surface seawater
; Adsorption
; Biological materials
; Carbon
; Dissolution
; Dust
; Iron
; Iron compounds
; Scavenging
; Seawater
; Agglomeration
; adsorption
; aggregate
; air-sea interaction
; biogeochemistry
; complexation
; concentration (composition)
; depositional environment
; dissolution
; dissolved organic matter
; iron
; ligand
; particle settling
; scavenging (chemistry)
; sea surface
; seawater
; solubility
英文摘要: Abiotic iron removal processes such as scavenging can significantly and rapidly modify iron distribution in the dissolved-colloidal-particulate continuum. Therefore, these processes could be considered, in addition to ligand complexation, as a major control on atmospheric iron dissolution in seawater. In this work, we investigated the seasonal abiotic processes occurring once dust deposited on surface seawater using a series of artificial seeding experiments (allowing us to take into consideration the settling of particles on a 1 m depth layer). Here, we demonstrate that atmospheric dissolved iron concentration ([DFe]) is driven by the processes governed by the dissolved organic matter (DOM) pool. Following artificial dust seeding, an order magnitude range increase in the [DFe] (12 - 181 nmol L-1) was observed depending on the season. Under high and fresh DOM conditions (spring and summer), the rapid formation of aggregates induced a negative feedback on the [DFe] through scavenging, while a fraction of the DFe was likely organically complexed. In contrast, in low-DOM surface waters (winter), aggregation was not observed, allowing a very large transient increase in [DFe] (181 nmol L-1) before being removed by adsorption onto settling particles. A key result of the findings is that depending on the age and quantity of DOM, the "lithogenic carbon pump" is likely a major pathway for organic carbon export. Modeling studies should therefore relate both atmospheric iron dissolution in seawater and the intensity of the subsequent biological response, to the age and quantity of DOM. Key Points Atmospheric iron dissolution is driven by the dissolved organic matter poolSeawater biogeochemical conditions are a key determinant of iron solubilityLithogenic carbon pump is likely a major pathway for organic carbon export. © 2013. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/77581
Appears in Collections: 气候变化事实与影响
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作者单位: ACRI-ST, Sophia-Antipolis, France; Laboratoire d'Océanographie de Villefranche/Mer, CNRS-INSU, Observatoire Océanologique, Chemin du Lazaret, FR-06230 Villefranche-sur-Mer, France
Recommended Citation:
Bressac M,, Guieu C. Post-depositional processes: What really happens to new atmospheric iron in the ocean's surface?[J]. Global Biogeochemical Cycles,2013-01-01,27(3)