DOI: 10.1029/2018GB006032
论文题名: Detection of Transient Denitrification During a High Organic Matter Event in the Black Sea
作者: Fuchsman C.A. ; Paul B. ; Staley J.T. ; Yakushev E.V. ; Murray J.W.
刊名: Global Biogeochemical Cycles
ISSN: 0886-6236
EISSN: 1944-9224
出版年: 2019
卷: 33, 期: 2 语种: 英语
英文关键词: ammonia
; bacterium
; denitrification
; nitrogen
; nitrogen isotope
; organic matter
; oxidation
; particulate organic matter
; remineralization
; stable isotope
; water column
; Black Sea
学科: anammox
; black sea
; denitrification
; N 2 gas
; organic matter
; stable N isotopes
中文摘要: N 2 production by denitrification can occur in anoxic water or potentially inside organic particles. Here we compare data from the Black Sea, a permanently anoxic basin, during two organic matter regimes: suspended particulate organic matter concentrations were high in the oxycline after the spring bloom in March 2005 compared to lower organic matter concentrations in June 2005, May and October 2007, July 2008, and May 2001. For all cruises, N 2 gas had a maximum in the suboxic zone (O 2 < 10 μmol/L). During the high organic matter event (March 2005), an additional shallower N 2 gas and δ 15 N-N 2 maxima occurred above the suboxic zone in the oxycline where oxygen concentrations were 30–50 μmol/L. Examination of 16S rRNA indicated that anammox bacteria were not present in the oxycline. The δ 15 N of biologically produced N 2 in the oxycline in March 2005 was significantly enriched (+7‰ to +38‰), not depleted, as would be expected from water column fractionation. A simple diffusion calculation indicated that ammonium produced from remineralization inside particles could be oxidized to nitrate and then completely consumed by denitrification inside the particle. In this calculation, half of denitrified N atoms originated from organic N [δ 15 N = 11‰] and half of N atoms originated from ambient nitrate [δ 15 N = 5‰–7‰], producing enriched δ 15 N-N 2 values. We suggest that denitrifiers were active in microzones inside particulates in hypoxic waters above the suboxic zone of the Black Sea. Denitrification in particles may also explain previous data from the oxycline above ocean oxygen deficient zones. ©2019. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/160152
Appears in Collections: 气候变化与战略
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作者单位: School of Oceanography, University of Washington, Seattle, WA, United States; Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, MD, United States; Department of Microbiology, University of Washington, Seattle, WA, United States; Norwegian Institute for Water Research, Oslo, Norway; P.P. Shirshov Institute of Oceanology (Russian Academy of Sciences), Moscow, Russian Federation
Recommended Citation:
Fuchsman C.A.,Paul B.,Staley J.T.,et al. Detection of Transient Denitrification During a High Organic Matter Event in the Black Sea[J]. Global Biogeochemical Cycles,2019-01-01,33(2)