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Titel |
Stability and biodegradability of organic matter from Arctic soils of Western Siberia: Insights from 13C-NMR spectroscopy and elemental analysis |
VerfasserIn |
Elisabet Ejarque, Evgeny Abakumov |
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 |
250131798
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Publikation (Nr.) |
EGU/EGU2016-12241.pdf |
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Zusammenfassung |
Arctic soils contain large amounts of organic matter which, globally, exceed the amount of
carbon stored in vegetation biomass and in the atmosphere. Recent studies emphasize the
potential sensitivity for this soil organic matter (SOM) to be mineralised when faced with
increasing ambient temperatures. In order to better refine the predictions about the response
of SOM to climate warming, there is a need to increase the spatial coverage of empirical data
on SOM quantity and quality in the Arctic area. This study provides, for the first time, a
characterisation of SOM from the Gydan Peninsula in the Yamal Region, Western
Siberia, Russia. On the one hand, soil humic acids and their humification state were
characterised by measuring the elemental composition and diversity of functional
groups using solid-state 13C-NMR spectroscopy. Also, the total mineralisable carbon
was measured. Our results show that there is a predominance of aliphatic carbon
structures, with a distribution of functional groups that has a minimal variation both
regionally and within soil depth. Such vertical homogeneity and low level of aromaticity
reflects the accumulation in soil of lowly decomposed organic matter due to cold
temperatures. Mineralisation rates were found to be independent of SOM quality,
and to be mainly explained solely by the total carbon content. Overall, our results
provide further evidence on the sensitivity that the soils of Western Siberia may
have to increasing ambient temperatures and highlight the important role that this
region can play in the global carbon balance under the effects of climate warming. |
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