气候变化领域集成服务门户(CCPortal): The Role of Particle Size, Ballast, Temperature, and Oxygen in the Sinking Flux to the Deep Sea

CCPortal

DOI	10.1029/2017GB005710
	The Role of Particle Size, Ballast, Temperature, and Oxygen in the Sinking Flux to the Deep Sea
	Cram J.A.; Weber T.; Leung S.W.; McDonnell A.M.P.; Liang J.-H.; Deutsch C.
发表日期	2018
ISSN	0886-6236
EISSN	1944-9224
起始页码	858
结束页码	876
卷号	32 期号:5
英文摘要	The “transfer efficiency” of organic particles from the surface to depth is a critical determinant of ocean carbon sequestration. Recently, direct observations and geochemical analyses have revealed a systematic geographical pattern of transfer efficiency, which is highest in high latitude regions and lowest in the subtropical gyres. We evaluate the possible causes of this pattern using a mechanistic model of sinking particle dynamics. The model represents the size distribution of particles, the effects of mineral ballast, seawater temperature (which influences both particle settling velocity and microbial metabolic rates), and O2. Parameters are optimized within reasonable ranges to best match the observational constraints. Our model shows that no single factor can explain the observed pattern of transfer efficiency, but the biological effect of temperature on remineralization rate and particle size effects together can reproduce most of the regional variability with both factors contributing to low transfer efficiency in the subtropical gyres and high transfer efficiency in high latitudes. Particle density from mineral ballast has a similar directional effect to temperature and size but plays a substantially smaller role in our optimum solution, due to the opposing patterns of silicate and calcium carbonate ballasting. Oxygen effects modestly improved model fit by depressing remineralization rates and thus increasing transfer efficiency in the Eastern Tropical Pacific. Our model implies that climate-driven changes to upper ocean temperature and associated changes in surface plankton size distribution would reduce the carbon sequestration efficiency in a warmer ocean. ©2018. American Geophysical Union. All Rights Reserved.
英文关键词	ballast; biological pump; export flux; marine snow; remineralization
语种	英语
scopus关键词	ballast water; biogeochemical cycle; biological pump; carbon sequestration; deep sea; flux measurement; gyre; latitudinal gradient; marine snow; oxygen; particle settling; particle size; plankton; remineralization; subtropical region; temperature effect; water temperature; Pacific Ocean; Pacific Ocean (Tropical)
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/129825
作者单位	School of Oceanography, University of Washington, Seattle, WA, United States; School of Arts and Sciences, University of Rochester, Rochester, NY, United States; College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, United States; Department of Oceanography and Coastal Sciences, College of the Coast and Environment, Louisiana State University, Baton Rouge, LA, United States; Center for Computation and Technology, Louisiana State University, Baton Rouge, LA, United States
推荐引用方式 GB/T 7714	Cram J.A.,Weber T.,Leung S.W.,et al. The Role of Particle Size, Ballast, Temperature, and Oxygen in the Sinking Flux to the Deep Sea[J],2018,32(5).
APA	Cram J.A.,Weber T.,Leung S.W.,McDonnell A.M.P.,Liang J.-H.,&Deutsch C..(2018).The Role of Particle Size, Ballast, Temperature, and Oxygen in the Sinking Flux to the Deep Sea.Global Biogeochemical Cycles,32(5).
MLA	Cram J.A.,et al."The Role of Particle Size, Ballast, Temperature, and Oxygen in the Sinking Flux to the Deep Sea".Global Biogeochemical Cycles 32.5(2018).