气候变化领域集成服务门户(CCPortal): Systematic Variation in Marine Dissolved Organic Matter Stoichiometry and Remineralization Ratios as a Function of Lability

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DOI	10.1029/2019GB006375
	Systematic Variation in Marine Dissolved Organic Matter Stoichiometry and Remineralization Ratios as a Function of Lability
	Zakem E.J.; Levine N.M.
发表日期	2019
ISSN	0886-6236
EISSN	1944-9224
起始页码	1389
结束页码	1407
卷号	33 期号:11
英文摘要	Remineralization of organic matter by heterotrophic organisms regulates the biological sequestration of carbon, thereby mediating atmospheric CO2. While surface nutrient supply impacts the elemental ratios of primary production, stoichiometric control by remineralization remains unclear. Here we develop a mechanistic description of remineralization and its stoichiometry in a marine microbial ecosystem model. The model simulates the observed elemental plasticity of phytoplankton and the relatively constant, lower C:N of heterotrophic biomass. In addition, the model captures the observed decreases in the C:N of more labile dissolved organic matter (DOM) and the C:N of its remineralization with depth, which are driven by a switch in the dominant source of DOM from phytoplankton to heterotrophic biomass. Only a model version with targeted remineralization of N-rich components is able to simulate the observed profiles of preferential remineralization of N relative to C and the elevated C:N of bulk DOM. The model suggests that more labile substrates are associated with C-limited heterotrophic growth and not with preferential remineralization, while less labile substrates are associated with growth limited by processing rates and with preferential remineralization. The resulting patterns of variable remineralization stoichiometry mediate the extent to which a proportional increase in carbon production resulting from changes in phytoplankton stoichiometry can increase the efficiency of the biological pump. Results emphasize the importance of understanding the physiology of both phytoplankton and heterotrophs for anticipating changes in biologically driven ocean carbon storage. ©2019. The Authors.
英文关键词	biogeochemistry; carbon cycle; dissolved organic matter; heterotroph; microbial ecology; remineralization
语种	英语
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/129699
作者单位	Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
推荐引用方式 GB/T 7714	Zakem E.J.,Levine N.M.. Systematic Variation in Marine Dissolved Organic Matter Stoichiometry and Remineralization Ratios as a Function of Lability[J],2019,33(11).
APA	Zakem E.J.,&Levine N.M..(2019).Systematic Variation in Marine Dissolved Organic Matter Stoichiometry and Remineralization Ratios as a Function of Lability.Global Biogeochemical Cycles,33(11).
MLA	Zakem E.J.,et al."Systematic Variation in Marine Dissolved Organic Matter Stoichiometry and Remineralization Ratios as a Function of Lability".Global Biogeochemical Cycles 33.11(2019).