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| Titel |
Carbon balance of a fertile forestry-drained peatland in southern Finland |
| VerfasserIn |
Annalea Lohila, Mika Korkiakoski, Juha-Pekka Tuovinen, Kari Minkkinen, Timo Penttilä, Paavo Ojanen, Samuli Launiainen, Tuomas Laurila |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250133454
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| Publikation (Nr.) |
 EGU/EGU2016-14066.pdf |
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| Zusammenfassung |
| Forestry on peatlands is a significant land use form and has been economically important
during the last decades particularly in the Nordic countries. While nutrient-poor forests are
generally able to maintain their carbon sink status even after drainage, the peat soil at the
fertile sites is typically considered as a large carbon dioxide (CO2) source. This
means that despite of high timber production capacity, the fertile peatland forests
gradually lose their peat carbon store. In addition, many of the nutrient-rich sites emit
considerable amount of nitrous oxide (N2O) into the atmosphere. While the current
estimates of the greenhouse gas (GHG) balance of forestry-drained peatlands are
largely based on soil inventories or on data combining soil GHG fluxes and tree
growth litter input measurements and modelling, only few studies have utilized the
high-resolution, continuous eddy covariance (EC) data to address the short-term dynamics
of the net CO2 fluxes covering both the soil, forest floor vegetation and the trees.
Hence, little is known about the factors which control the year-to-year variation in
fluxes. Here we present a 5-year dataset of CO2 fluxes measured with the EC method
above a nutrient-rich forestry-drained peatland in southern Finland. The site, drained
in the beginning of 1970’s, is a well growing pine forest with some spruces and
birches, the tree volume and carbon fixation rate equaling 8.0 kg C m−2 and 0.273
kg C m−2 yr−1, respectively. The average summer-time water level depth is -50
cm.
By combining the gap-filled half-hourly net ecosystem exchange (NEE) data, the tree
growth measurements, and the measurements on dissolved organic carbon (DOC) losses and
soil methane (CH4) exchange, we will in this presentation estimate the total annual loss of
peat carbon of this fertile peatland forest. In addition, using the N2O flux data we
will estimate the contribution of different gases to the total GHG balance. Factors
controlling the carbon balance and its seasonal and inter-annual variation are discussed. |
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