DOI: 10.1029/2018JG004518
Scopus记录号: 2-s2.0-85052393841
论文题名: Adding Depth to Our Understanding of Nitrogen Dynamics in Permafrost Soils
作者: Salmon V.G. ; Schädel C. ; Bracho R. ; Pegoraro E. ; Celis G. ; Mauritz M. ; Mack M.C. ; Schuur E.A.G.
刊名: Journal of Geophysical Research: Biogeosciences
ISSN: 21698953
出版年: 2018
卷: 123, 期: 8 起始页码: 2497
结束页码: 2512
语种: 英语
英文关键词: mineralization
; moist acidic tussock tundra
; nitrogen availability
; permafrost thaw
; soil depth
英文摘要: Losses of C from decomposing permafrost may be offset by increased productivity of tundra plants, but nitrogen availability partially limits plant growth in tundra ecosystems. In this soil incubation experiment carbon (C) and nitrogen (N) cycling dynamics were examined from the soil surface down through upper permafrost. We found that losses of CO2 were negatively correlated to net N mineralization because C-rich surface soils mineralized little N, while deep soils had low rates of C respiration but high rates of net N mineralization. Permafrost soils released a large flush of inorganic N when initially thawed. Depth-specific rates of N mineralization from the incubation were combined with thaw depths and soil temperatures from a nearby manipulative warming experiment to simulate the potential magnitude, timing, and depth of inorganic N release during the process of permafrost thaw. Our calculations show that inorganic N released from newly thawed permafrost may be similar in magnitude to the increase in N mineralized by warmed soils in the middle of the profile. The total release of inorganic N from the soil profile during the simulated thaw process was twice the size of the observed increase in the foliar N pool observed at the manipulative experiment. Our findings suggest that increases in N availability are likely to outpace the N demand of tundra plants during the first 5 years of permafrost thaw and may increase C losses from surface soils as well as induce denitrification and leaching of N from these ecosystems. ©2018. 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/113417
Appears in Collections: 气候减缓与适应
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作者单位: Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, United States; Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, United States; School of Forest Resources and Conservation, University of Florida, Gainesville, FL, United States; Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, United States
Recommended Citation:
Salmon V.G.,Schädel C.,Bracho R.,et al. Adding Depth to Our Understanding of Nitrogen Dynamics in Permafrost Soils[J]. Journal of Geophysical Research: Biogeosciences,2018-01-01,123(8)