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| Titel |
Short term changes of microbial processes in Icelandic soils to increasing temperatures |
| VerfasserIn |
R. Guicharnaud, O. Arnalds, G. I. Paton |
| 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 ; 7, no. 2 ; Nr. 7, no. 2 (2010-02-17), S.671-682 |
| Datensatznummer |
250004495
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| Publikation (Nr.) |
 copernicus.org/bg-7-671-2010.pdf |
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| Zusammenfassung |
Temperature change is acknowledged to have a significant effect on soil
biological processes and the corresponding sequestration of carbon and
cycling of nutrients. Soils at high latitudes are likely to be particularly
impacted by increases in temperature. Icelandic soils experience unusually
frequent freeze and thaw cycles compare to other Arctic regions, which are
increasing due to a warming climate. As a consequence these soils are
frequently affected by short term temperature fluctuations.
In this study, the short term response of a range of soil microbial
parameters (respiration, nutrient availability, microbial biomass carbon,
arylphosphatase and dehydrogenase activity) to temperature changes was
measured in sub-arctic soils collected from across Iceland. Sample sites
reflected two soil temperature regimes (cryic and frigid) and two land uses
(pasture and arable). The soils were sampled from the field frozen,
equilibrated at −20 °C and then incubated for two weeks at −10 °C,
−2 °C, +2 °C and +10 °. Respiration and enzymatic activity were
temperature dependent. The soil temperature regime affected the soil
microbial biomass carbon sensitivity to temperatures. When soils where
sampled from the cryic temperature regime a decreasing soil microbial
biomass was detected when temperatures rose above the freezing point. Frigid
soils, sampled from milder climatic conditions, where unaffected by
difference in temperatures. Nitrogen mineralisation did not change with
temperature. At −10 °C, dissolved organic carbon accounted for 88% of
the fraction of labile carbon which was significantly greater than that
recorded at +10 °C when dissolved organic carbon accounted for as low as
42% of the labile carbon fraction. |
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