气候变化领域集成服务门户(CCPortal): Theoretical Considerations on Factors Confounding the Interpretation of the Oceanic Carbon Export Ratio

CCPortal

DOI	10.1029/2018GB006003
	Theoretical Considerations on Factors Confounding the Interpretation of the Oceanic Carbon Export Ratio
	Li Z.; Cassar N.
发表日期	2018
ISSN	0886-6236
EISSN	1944-9224
起始页码	1644
结束页码	1658
卷号	32 期号:11
英文摘要	The fraction of primary production exported out of the surface ocean, known as the export ratio (ef ratio), is often used to assess how various factors, including temperature, primary production, phytoplankton size, and community structure, affect the export efficiency of an ecosystem. To investigate possible causes for reported discrepancies in the dominant factors influencing the export efficiency, we develop a metabolism-based mechanistic model of the ef ratio. Consistent with earlier studies, we find based on theoretical considerations that the ef ratio is a negative function of temperature. We show that the ef ratio depends on the optical depth, defined as the physical depth times the light attenuation coefficient. As a result, varying light attenuation may confound the interpretation of ef ratio when measured at a fixed depth (e.g., 100 m) or at the base of the mixed layer. Finally, we decompose the contribution of individual factors on the seasonality of the ef ratio. Our results show that at high latitudes, the ef ratio at the base of mixed layer is strongly influenced by mixed layer depth and surface irradiation on seasonal time scales. Future studies should report the ef ratio at the base of the euphotic layer or account for the effect of varying light attenuation if measured at a different depth. Overall, our modeling study highlights the large number of factors confounding the interpretation of field observations of the ef ratio. ©2018. American Geophysical Union. All Rights Reserved.
英文关键词	export production; net community production; net primary production; oceanic carbon export ratio
语种	英语
scopus关键词	carbon cycle; community structure; ecosystem dynamics; environmental factor; euphotic zone; global ocean; irradiation; light attenuation; metabolism; mixed layer; phytoplankton; primary production; seasonality; theoretical study
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/129777
作者单位	Division of Earth and Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, NC, United States; Now at Woods Hole Oceanographic Institution, Woods Hole, MA, United States
推荐引用方式 GB/T 7714	Li Z.,Cassar N.. Theoretical Considerations on Factors Confounding the Interpretation of the Oceanic Carbon Export Ratio[J],2018,32(11).
APA	Li Z.,&Cassar N..(2018).Theoretical Considerations on Factors Confounding the Interpretation of the Oceanic Carbon Export Ratio.Global Biogeochemical Cycles,32(11).
MLA	Li Z.,et al."Theoretical Considerations on Factors Confounding the Interpretation of the Oceanic Carbon Export Ratio".Global Biogeochemical Cycles 32.11(2018).