气候变化领域集成服务门户(CCPortal): New Insights Into Processes Controlling the δ30Si of Sinking Diatoms: A Seasonally Resolved Box Model Approach

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DOI	10.1029/2018GB006115
	New Insights Into Processes Controlling the δ30Si of Sinking Diatoms: A Seasonally Resolved Box Model Approach
	Closset I.; Cardinal D.; Trull T.W.; Fripiat F.
发表日期	2019
ISSN	0886-6236
EISSN	1944-9224
起始页码	957
结束页码	970
卷号	33 期号:8
英文摘要	In the Southern Ocean, the silicon (Si) biogeochemical cycle is dominated by processes such as the supply of Si into the surface waters, Si uptake into diatom frustules, and their subsequent dissolution and export. Due to the incomplete assimilation of the silicic acid pool (DSi) and isotopic fractionation during silicification, the Si isotopic composition (δ30Si) of biogenic silica (BSi) is closely linked to the degree of Si utilization in the mixed layer (ML). In this study, we combined modelling approaches and seasonal sediment trap records of δ30Si of exported BSi to investigate the magnitude, timing, and isotopic composition of the flux of siliceous particles transferred from the surface to the deep ocean. We implemented a box model to describe the temporal evolution of DSi and BSi concentrations and δ30Si in the ML and at depth. The model allows us to quantify fluxes of Si in and out of the ML associated with export, dissolution, and mixing. It highlights that the time-integrated δ30Si of exported BSi measured in the sediments reflects the extent of DSi consumption at the time when net BSi production and diatom accumulation are maximal in the ML and confirms that the δ30Si of diatoms is a reliable proxy for past Si utilization. ©2019. American Geophysical Union. All Rights Reserved.
英文关键词	diatoms; export production; model; silicon cycle; silicon isotopes; Southern Ocean
语种	英语
scopus关键词	biogeochemical cycle; concentration (composition); diatom; dissolution; isotopic composition; isotopic fractionation; mixed layer; seasonal variation; sediment trap; silicic acid; silicon; surface water; temporal evolution; Bacillariophyta
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/129723
作者单位	MSI, University of California Santa Barbara, Santa Barbara, CA, United States; LOCEAN UMR 7159 Sorbonne Université/CNRS/IRD/MNHN, Paris, France; Antarctic Climate and Ecosystems Cooperative Research Center, University of Tasmania, Hobart, TAS, Australia; CSIRO Oceans and Atmosphere, Hobart, TAS, Australia; Max Planck Institute for Chemistry, Mainz, Germany
推荐引用方式 GB/T 7714	Closset I.,Cardinal D.,Trull T.W.,et al. New Insights Into Processes Controlling the δ30Si of Sinking Diatoms: A Seasonally Resolved Box Model Approach[J],2019,33(8).
APA	Closset I.,Cardinal D.,Trull T.W.,&Fripiat F..(2019).New Insights Into Processes Controlling the δ30Si of Sinking Diatoms: A Seasonally Resolved Box Model Approach.Global Biogeochemical Cycles,33(8).
MLA	Closset I.,et al."New Insights Into Processes Controlling the δ30Si of Sinking Diatoms: A Seasonally Resolved Box Model Approach".Global Biogeochemical Cycles 33.8(2019).