Advanced

Controls of spatial and temporal variability in CH4 flux in a high arctic fen over three years

Ström, Lena LU ; Falk, Julie Maria LU ; Skov, Kirstine; Jackowicz-Korczynski, Marcin LU ; Mastepanov, Mikhail LU ; Christensen, Torben LU ; Lund, Magnus LU and Schmidt, Niels Martin (2015) In Biogeochemistry 125(1). p.21-35
Abstract
The aim of this study was to establish the main drivers of the spatial variability in growing season CH4 flux within an arctic wetland ecosystem. During 3 years (2011-2013) we measured CH4 flux and potential drivers, e.g., CO2 fluxes (net ecosystem exchange (NEE), gross primary productivity (GPP) and ecosystem respiration), temperature, water table depth, pore-water concentration of organic acids (e.g., acetate) and the vascular plant composition and density. The study included 16-20 main plots (C-main) and in 2013 also experimental plots (10 excluded muskoxen grazing, 9 snow fence and 10 automated chamber plots) distributed over 0.3 km(2). The results show a 1.8-times difference in CH4 flux magnitude inter-annually and 9- to 35-times... (More)
The aim of this study was to establish the main drivers of the spatial variability in growing season CH4 flux within an arctic wetland ecosystem. During 3 years (2011-2013) we measured CH4 flux and potential drivers, e.g., CO2 fluxes (net ecosystem exchange (NEE), gross primary productivity (GPP) and ecosystem respiration), temperature, water table depth, pore-water concentration of organic acids (e.g., acetate) and the vascular plant composition and density. The study included 16-20 main plots (C-main) and in 2013 also experimental plots (10 excluded muskoxen grazing, 9 snow fence and 10 automated chamber plots) distributed over 0.3 km(2). The results show a 1.8-times difference in CH4 flux magnitude inter-annually and 9- to 35-times spatially (depending on year and treatment). During all 3 years GPP was a strong driver of the variability in C-main plots. Accordingly, the plant productivity related variables NEE, GPP and acetate were singled out as the strongest drivers of the variability in 2013, when all variables were measured on a majority of the plots. These variables were equally strong drivers of the spatial variability in CH4 flux regardless of whether experimental plots were included in the analysis or not. The density of Eriophorum scheuchzeri was the strongest driver of the spatial variability in NEE, GPP and acetate. In conclusion, changes in vegetation composition or productivity of wet arctic ecosystems will have large impacts on their carbon balance and CH4 flux, irrespective of whether these changes are driven directly by climate change or by biotic interactions, such as grazing. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Arctic wetlands, CH4 flux, Eriophorum, Spatial variability, Substrate, availability
in
Biogeochemistry
volume
125
issue
1
pages
21 - 35
publisher
Springer
external identifiers
  • wos:000358598200003
  • scopus:84938290486
ISSN
1573-515X
DOI
10.1007/s10533-015-0109-0
language
English
LU publication?
yes
id
4d5f5561-6fc0-48bf-a89f-fc68b88843eb (old id 7767723)
date added to LUP
2015-09-09 13:56:55
date last changed
2017-10-01 03:16:50
@article{4d5f5561-6fc0-48bf-a89f-fc68b88843eb,
  abstract     = {The aim of this study was to establish the main drivers of the spatial variability in growing season CH4 flux within an arctic wetland ecosystem. During 3 years (2011-2013) we measured CH4 flux and potential drivers, e.g., CO2 fluxes (net ecosystem exchange (NEE), gross primary productivity (GPP) and ecosystem respiration), temperature, water table depth, pore-water concentration of organic acids (e.g., acetate) and the vascular plant composition and density. The study included 16-20 main plots (C-main) and in 2013 also experimental plots (10 excluded muskoxen grazing, 9 snow fence and 10 automated chamber plots) distributed over 0.3 km(2). The results show a 1.8-times difference in CH4 flux magnitude inter-annually and 9- to 35-times spatially (depending on year and treatment). During all 3 years GPP was a strong driver of the variability in C-main plots. Accordingly, the plant productivity related variables NEE, GPP and acetate were singled out as the strongest drivers of the variability in 2013, when all variables were measured on a majority of the plots. These variables were equally strong drivers of the spatial variability in CH4 flux regardless of whether experimental plots were included in the analysis or not. The density of Eriophorum scheuchzeri was the strongest driver of the spatial variability in NEE, GPP and acetate. In conclusion, changes in vegetation composition or productivity of wet arctic ecosystems will have large impacts on their carbon balance and CH4 flux, irrespective of whether these changes are driven directly by climate change or by biotic interactions, such as grazing.},
  author       = {Ström, Lena and Falk, Julie Maria and Skov, Kirstine and Jackowicz-Korczynski, Marcin and Mastepanov, Mikhail and Christensen, Torben and Lund, Magnus and Schmidt, Niels Martin},
  issn         = {1573-515X},
  keyword      = {Arctic wetlands,CH4 flux,Eriophorum,Spatial variability,Substrate,availability},
  language     = {eng},
  number       = {1},
  pages        = {21--35},
  publisher    = {Springer},
  series       = {Biogeochemistry},
  title        = {Controls of spatial and temporal variability in CH4 flux in a high arctic fen over three years},
  url          = {http://dx.doi.org/10.1007/s10533-015-0109-0},
  volume       = {125},
  year         = {2015},
}