DOI: 10.1029/2017JG004344
Scopus记录号: 2-s2.0-85049833129
论文题名: Nitrogen Budget and Topographic Controls on Nitrous Oxide in a Shale-Based Watershed
作者: Weitzman J.N. ; Kaye J.P.
刊名: Journal of Geophysical Research: Biogeosciences
ISSN: 21698953
出版年: 2018
卷: 123, 期: 6 起始页码: 1888
结束页码: 1908
语种: 英语
英文关键词: N budget
; nitrous oxide
; topography
Scopus关键词: atmospheric deposition
; nitrogen cycle
; nitrous oxide
; nutrient budget
; saturation
; shale
; soil surface
; source-sink dynamics
; spatiotemporal analysis
; topographic effect
; watershed
; Pennsylvania
; Shale Hills
; United States
英文摘要: The high spatial and temporal variabilities of nitrous oxide (N2O) emissions from the soil surface have made it difficult to predict flux patterns at the ecosystem scale, leading to imbalances in nitrogen (N) budgets at all scales. Our research sought to quantify topographic controls on the sources or sinks of N2O in the soil profile to improve our ability to predict soil-atmosphere N2O fluxes and their contribution to watershed N budgets. We monitored surface-to-atmosphere N2O fluxes for 2 years in the Susquehanna Shale Hills Critical Zone Observatory in central Pennsylvania. Topographically convergent flow path locations had significantly higher surface N2O flux rates than nonconvergent flow path locations in the summer, but not other seasons. Overall, N2O fluxes were a large percentage (~19%) of total ecosystem N losses, and nearly twice as large as stream N export. Surface N2O fluxes were better correlated with concentrations of O2, N2O, and NO3 − in shallow soil layers (<30 cm) than deeper soils. Following decades of anthropogenic atmospheric deposition and additional N from shale weathering, watershed N inputs (~8 kgN ha−1 yr−1) are greater than outputs (~3.7 kgN ha−1 yr−1). Our research revealed patterns of N cycling that are distinct from many other watersheds that have been extensively studied to understand N saturation; despite showing no other symptoms of N saturation, the watershed had high upland N2O losses, especially in convergent flow paths during summer. High upland N gas losses may be a mechanism that maintains N limitation to biota in the Shale Hills catchment. ©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/113760
Appears in Collections: 气候减缓与适应
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作者单位: Department of Ecosystem Science and Management, The Pennsylvania State University, University Park, PA, United States; Now at CUNY Advanced Science Research Center, New York, NY, United States; Cary Institute of Ecosystem Studies, Millbrook, NY, United States
Recommended Citation:
Weitzman J.N.,Kaye J.P.. Nitrogen Budget and Topographic Controls on Nitrous Oxide in a Shale-Based Watershed[J]. Journal of Geophysical Research: Biogeosciences,2018-01-01,123(6)