DOI: 10.1111/gcb.14895
论文题名: Stream metabolism controls diel patterns and evasion of CO2 in Arctic streams
作者: Rocher-Ros G. ; Sponseller R.A. ; Bergström A.-K. ; Myrstener M. ; Giesler R.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2020
卷: 26, 期: 3 语种: 英语
英文关键词: Arctic
; carbon cycle
; carbon processing
; CO2 evasion
; stream metabolism
Scopus关键词: arctic environment
; carbon cycle
; carbon dioxide
; concentration (composition)
; diel variation
; metabolism
; oxygen
; stream
; tundra
; Sweden
英文摘要: Streams play an important role in the global carbon (C) cycle, accounting for a large portion of CO2 evaded from inland waters despite their small areal coverage. However, the relative importance of different terrestrial and aquatic processes driving CO2 production and evasion from streams remains poorly understood. In this study, we measured O2 and CO2 continuously in streams draining tundra-dominated catchments in northern Sweden, during the summers of 2015 and 2016. From this, we estimated daily metabolic rates and CO2 evasion simultaneously and thus provide insight into the role of stream metabolism as a driver of C dynamics in Arctic streams. Our results show that aquatic biological processes regulate CO2 concentrations and evasion at multiple timescales. Photosynthesis caused CO2 concentrations to decrease by as much as 900 ppm during the day, with the magnitude of this diel variation being strongest at the low-turbulence streams. Diel patterns in CO2 concentrations in turn influenced evasion, with up to 45% higher rates at night. Throughout the summer, CO2 evasion was sustained by aquatic ecosystem respiration, which was one order of magnitude higher than gross primary production. Furthermore, in most cases, the contribution of stream respiration exceeded CO2 evasion, suggesting that some stream reaches serve as net sources of CO2, thus creating longitudinal heterogeneity in C production and loss within this stream network. Overall, our results provide the first link between stream metabolism and CO2 evasion in the Arctic and demonstrate that stream metabolic processes are key drivers of the transformation and fate of terrestrial organic matter exported from these landscapes. © 2019 The Authors. Global Change Biology published by John Wiley & Sons Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/159020
Appears in Collections: 气候变化与战略
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作者单位: Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden
Recommended Citation:
Rocher-Ros G.,Sponseller R.A.,Bergström A.-K.,et al. Stream metabolism controls diel patterns and evasion of CO2 in Arctic streams[J]. Global Change Biology,2020-01-01,26(3)