Land-atmosphere interaction of a subarctic palsa mire
Författare
Summary, in English
The measured eddy covariance tower net ecosystem exchange (NEE) showed a strong and consistent annual uptake signal. During the years 2004 to 2008, with relatively comparable climates the annual NEE amounts to -89 g CO2-C m-2 y-1, with very small variation. The eddy covariance (EC) tower acquired CH4 flux measurements and showed a strong positive input to the annual carbon budget in the range of 18-22 g CH4-C m-2 y-1, reducing the studied ecosystem sink strength by almost 20%. Additional positive budget components in the form of emission of NMHCs constitute roughly an additional 15% to the CH4 fluxes. This fraction may be compared with the EC CH4 flux measurements emission rates and the results of the isoprene and methanol flux measurements obtained by the DEC method. Here the proportional atmospheric emission is estimated as 4% and 1% respectively for the above-mentioned components, indicating that other compounds must be responsible for a large proportion of the NMHC flux. By applying a global warming potential factor and calculating the annual balances expressed in CO2 equivalent numbers converted according to a 100 year time horizon, the degrading parts of the Stordalen mire appear as a greenhouse warming source with a level of emission estimated at +93 g CO2equiv.-C m-2 y-1. This strong greenhouse warming source demonstrates the necessity of conducting detailed carbon budgeting experiments that will lead to an improvement of our understanding of how global carbon cycling interacts with climate.
Publiceringsår
2009
Språk
Engelska
Publikation/Tidskrift/Serie
Meddelanden från Lunds universitets geografiska institution. Avhandlingar
Volym
184
Dokumenttyp
Doktorsavhandling
Förlag
GeoBiosphere Science Centre, Department of Physical Geography and Ecosystems Analysis, Lund University, Sölvegatan 12, 223 62, Lund, Sweden
Ämne
- Physical Geography
Nyckelord
- eddy covariance
- chamber
- methnaol
- isoprene
- nonmethane hydrocarbons
- methane
- carbon dioxide
- carbon
- mire
- permafrost
- subarctic
- palsa
- greenhouse gas
Aktiv
Published
Handledare
- Torben Christensen
ISBN/ISSN/Övrigt
- ISSN: 0346-6787
- ISBN: 978-91-85793-09-9
Försvarsdatum
8 juni 2009
Försvarstid
10:00
Försvarsplats
Världen, Geocentrum I, Sölvegatan 10, 223 62, Lund, Sweden
Opponent
- Peter M. Lafleur