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| Titel |
Seasonal dynamics of methane emissions from a subarctic fen in the Hudson Bay Lowlands |
| VerfasserIn |
K. L. Hanis, M. Tenuta, B. D. Amiro, T. N. Papakyriakou |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1726-4170
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| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 10, no. 7 ; Nr. 10, no. 7 (2013-07-03), S.4465-4479 |
| Datensatznummer |
250018324
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| Publikation (Nr.) |
 copernicus.org/bg-10-4465-2013.pdf |
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| Zusammenfassung |
| Ecosystem-scale methane (CH4) flux (FCH4) over a
subarctic fen at Churchill, Manitoba, Canada was measured to understand the
magnitude of emissions during spring and fall shoulder seasons, and the
growing season in relation to physical and biological conditions.
FCH4 was measured using eddy covariance with a closed-path
analyser in four years (2008–2011). Cumulative measured annual
FCH4 (shoulder plus growing seasons) ranged from 3.0 to
9.6 g CH4 m−2 yr−1 among the four study years, with a mean
of 6.5 to 7.1 g CH4 m−2 yr−1 depending upon gap-filling
method. Soil temperatures to depths of 50 cm and air temperature were highly
correlated with FCH4, with near-surface soil temperature at
5 cm most correlated across spring, fall, and the shoulder and growing seasons. The response
of FCH4 to soil temperature at the 5 cm depth and air
temperature was more than double in spring to that of fall. Emission episodes
were generally not observed during spring thaw. Growing season emissions also
depended upon soil and air temperatures but the water table also exerted
influence, with FCH4 highest when water was 2–13 cm
below and lowest when it was at or above the mean peat surface. |
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