DOI: 10.1007/s10533-017-0388-8
Scopus记录号: 2-s2.0-85031396842
论文题名: Compositional changes and molecular transformations of dissolved organic matter during the arctic spring floods in the lower Churchill watershed (Northern Manitoba, Canada)
作者: Mangal V. ; Shi Y.X. ; Guéguen C.
刊名: Biogeochemistry
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2017
卷: 136, 期: 2 起始页码: 151
结束页码: 165
语种: 英语
英文关键词: Dissolved organic matter
; Fluorescence
; Lignin mobilization
; Orbitrap mass spectrometry
; River discharge
; Spring freshet
Scopus关键词: absorbance
; chemical composition
; concentration (composition)
; dissolved organic matter
; flood
; fluorescence
; lignin
; mobilization
; molecular analysis
; peak flow
; protein
; river discharge
; spring (season)
; water quality
; watershed
; Canada
; Churchill
; Manitoba
英文摘要: The spring flood season in Northern aquatic systems is characterized by rapid changes in river discharge and fluxes of organic and inorganic species, yet remains under sampled. In this study, we examine the molecular characteristics and transformations of dissolved organic matter (DOM) during the Arctic spring season at three locations in the lower Churchill River watershed. Characteristics including dissolved organic carbon concentrations, optical properties (i.e. absorbance and, excitation-emission matrix fluorescence coupled with parallel factor analysis, EEM-PARAFAC) and molecular characterization using high resolution mass spectrometry (HR-MS) were assessed. As spring floods progressed, a significant reduction in DOM spectral slope (S275–295) and an increase in absorbance (a270) were observed suggesting an increase in DOM molecular weight and concentrations at all sampled locations. A maximum in HR-MS lignin-class compounds coincided with peak flow at all sampled locations, further validated with an increase in PARAFAC humic-like components and a minimum in S275–295. Principal component analyses revealed that both protein and aromatic humic-like material measured by HR-MS and EEM-PARAFAC, respectively, were significantly correlated (ANOVA, p < 0.05), demonstrating similarities in both techniques. Based on network analysis of HR-MS assigned formula, the highest peak flow day was characterized by a maximum in homologous DOM of C2H2O and C2H4 additions, suggesting structural similarities in newly deposited lignin and humic material. Overall, the progression of the spring freshet shifted the lower Churchill River watershed from an environment rich in proteins and lipids to an aquatic system more abundant in lignin, aromatic and humic DOM. © 2017, Springer International Publishing AG. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/83216
Appears in Collections: 气候减缓与适应 气候变化事实与影响
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作者单位: Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, Canada; Chemistry Department and Trent School of the Environment, Trent University, Peterborough, ON, Canada; Trent Water Quality Centre, Trent University, Peterborough, ON, Canada
Recommended Citation:
Mangal V.,Shi Y.X.,Guéguen C.. Compositional changes and molecular transformations of dissolved organic matter during the arctic spring floods in the lower Churchill watershed (Northern Manitoba, Canada)[J]. Biogeochemistry,2017-01-01,136(2)