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| Titel |
Effects of snow condition on microbial respiration of Scots pine needle litter in a boreal forest |
| VerfasserIn |
Masataka Ohnuki, Timo Domisch, Masako Dannoura, Mioko Ataka, Leena Finér, Tapani Repo, Akira Osawa |
| 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 |
250130981
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| Publikation (Nr.) |
 EGU/EGU2016-11323.pdf |
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| Zusammenfassung |
| Climate warming scenarios predict decreasing snow depths and increasing winter
precipitation in boreal forests (“rain on snow”). I These conditions may affect the
decomposition and the microbial respiration of leaf litter, contributing a major part of tree
litters, To understand how different snow conditions during winter would affect the microbial
respiration of Scots pine needle litter in a boreal forest, we conducted a laboratory
experiment using needle litter of two age classes (newly dropped and older litter).
The experiment simulated four different winter treatments, followed by spring and
early summer : (1) ambient snow cover (SNOW), (2) Compressed snow and ice
encasement (ICE), (3) frozen flood (FLOOD) and (4) no snow cover at all (NO
SNOW). The experiment was carried out in four walk-in dasotrons (n=3) with soil
temperatures of -2˚ C and air temperatures of 2˚ C during winter and increased to 15˚ C
and 20˚ C during spring, respectively . Needle litter samples were collected three
times (prior to the winter, just after winter and at the end of the experiment). We
evaluated the microbial respiration from the litter at several temperatures (-5˚ C, 0˚
C, 5˚ C and 12˚ C ), the SIR index (an index estimating the microbial biomass),
and the C/N ratio .And we calculated Q10 value (index of microbial respiration
activity) using microbial respiration data. We found significant differences in microbial
respiration between the newly dropped and older litter at the beginning and at the end of
the experiment. However, there were no significant differences in Q10 value and
the SIR (index of microbial biomass) between the different winter treatments. All
samples showed decrease of microbial activity with time. Finally, we conclude that the
winter snow conditions with mild air temperatures as used in our experiment, are not
detrimentally affecting the Scots pine needle litter decomposition and its respiration. |
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