气候变化领域集成服务门户(CCPortal): Isotopic Constraints on Nitrogen Transformation Rates in the Deep Sedimentary Marine Biosphere

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DOI	10.1029/2018GB005948
	Isotopic Constraints on Nitrogen Transformation Rates in the Deep Sedimentary Marine Biosphere
	Buchwald C.; Homola K.; Spivack A.J.; Estes E.R.; Murray R.W.; Wankel S.D.
发表日期	2018
ISSN	0886-6236
EISSN	1944-9224
起始页码	1688
结束页码	1702
卷号	32 期号:11
英文摘要	Little is known about the nature of microbial community activity contributing to the cycling of nitrogen in organic-poor sediments underlying the expansive oligotrophic ocean gyres. Here we use pore water concentrations and stable N and O isotope measurements of nitrate and nitrite to constrain rates of nitrogen cycling processes over a 34-m profile from the deep North Atlantic spanning fully oxic to anoxic conditions. Using a 1-D reaction-diffusion model to predict the distribution of nitrogen cycling rates, results converge on two distinct scenarios: (1) an exceptionally high degree of coupling between nitrite oxidation and nitrate reduction near the top of the anoxic zone or (2) an unusually large N isotope effect (~60‰) for nitrate reduction that is decoupled from the corresponding O isotope effect, which is possibly explained by enzyme-level interconversion between nitrite and nitrate. ©2018. American Geophysical Union. All Rights Reserved.
语种	英语
scopus关键词	biosphere; gyre; isotopic analysis; marine sediment; microbial activity; microbial community; nitrogen; nitrogen cycle; oligotrophic environment; one-dimensional modeling; oxidation; reduction; transformation; Atlantic Ocean; Atlantic Ocean (North)
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/129774
作者单位	Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States; Department of Oceanography, Dalhousie University, Halifax, NS, Canada; School of Oceanography, University of Rhode Island, Narragansett, RI, United States; Earth and Environment, Boston University, Boston, MA, United States
推荐引用方式 GB/T 7714	Buchwald C.,Homola K.,Spivack A.J.,et al. Isotopic Constraints on Nitrogen Transformation Rates in the Deep Sedimentary Marine Biosphere[J],2018,32(11).
APA	Buchwald C.,Homola K.,Spivack A.J.,Estes E.R.,Murray R.W.,&Wankel S.D..(2018).Isotopic Constraints on Nitrogen Transformation Rates in the Deep Sedimentary Marine Biosphere.Global Biogeochemical Cycles,32(11).
MLA	Buchwald C.,et al."Isotopic Constraints on Nitrogen Transformation Rates in the Deep Sedimentary Marine Biosphere".Global Biogeochemical Cycles 32.11(2018).