气候变化领域集成服务门户(CCPortal): The Significance of Giant Phaeodarians (Rhizaria) to Biogenic Silica Export in the California Current Ecosystem

CCPortal

DOI	10.1029/2018GB005877
	The Significance of Giant Phaeodarians (Rhizaria) to Biogenic Silica Export in the California Current Ecosystem
	Biard T.; Krause J.W.; Stukel M.R.; Ohman M.D.
发表日期	2018
ISSN	0886-6236
EISSN	1944-9224
起始页码	987
结束页码	1004
卷号	32 期号:6
英文摘要	In marine ecosystems, many planktonic organisms precipitate biogenic silica (bSiO2) to build silicified skeletons. Among them, giant siliceous rhizarians (>500 μm), including Radiolaria and Phaeodaria, are important contributors to oceanic carbon pools but little is known about their contribution to the marine silica cycle. We report the first analyses of giant phaeodarians to bSiO2 export in the California Current Ecosystem. We measured the silica content of single rhizarian cells ranging in size from 470 to 3,920 μm and developed allometric equations to predict silica content (0.37–43.42 μg Si/cell) from morphometric measurements. Using sediment traps to measure phaeodarian fluxes from the euphotic zone on four cruises, we calculated bSiO2 export produced by two families, the Aulosphaeridae and Castanellidae. Biogenic silica export ranged from <0.01 to 0.63 mmol Si · m−2 · day−1. These two families alone contributed on average 10% (range 0–80%) of total bSiO2 export from the euphotic zone. Their proportional contributions increased substantially in more oligotrophic regions with lower bSiO2 fluxes. Using the in situ Underwater Vision Profiler 5, we characterized vertical distributions of the giant phaeodarian family Aulosphaeridae to a depth of 500 m and inferred their contribution to bSiO2 export in deeper waters. We found a significant increase of Aulosphaeridae export (<0.01 to 2.82 mmol Si · m−2 · day−1) when extended to mesopelagic depths. Using a global data set of in situ profiles, we estimated the significance of Aulosphaeridae to bSiO2 export and revealed that they can act as major exporters of bSiO2 to the mesopelagic zone in various regions. ©2018. American Geophysical Union. All Rights Reserved.
英文关键词	California Current Ecosystem; export; in situ imagery; marine silica cycle; Phaeodaria; Rhizaria
语种	英语
scopus关键词	allometry; cell; eukaryote; euphotic zone; flux measurement; in situ measurement; mesopelagic zone; morphometry; plankton; sediment trap; silica; California Current; Pacific Ocean; Aulosphaeridae; Phaeodarea; Rhizaria
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/129817
作者单位	Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, United States; Dauphin Island Sea Lab, Dauphin Island, AL, United States; Department of Marine Sciences, University of South Alabama, Mobile, AL, United States; Earth, Ocean, and Atmospheric Science Department, Florida State University, Tallahassee, FL, United States
推荐引用方式 GB/T 7714	Biard T.,Krause J.W.,Stukel M.R.,et al. The Significance of Giant Phaeodarians (Rhizaria) to Biogenic Silica Export in the California Current Ecosystem[J],2018,32(6).
APA	Biard T.,Krause J.W.,Stukel M.R.,&Ohman M.D..(2018).The Significance of Giant Phaeodarians (Rhizaria) to Biogenic Silica Export in the California Current Ecosystem.Global Biogeochemical Cycles,32(6).
MLA	Biard T.,et al."The Significance of Giant Phaeodarians (Rhizaria) to Biogenic Silica Export in the California Current Ecosystem".Global Biogeochemical Cycles 32.6(2018).