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| Titel |
Changes in vascular plant functional types drive carbon cycling in peatlands |
| VerfasserIn |
Lilli Zeh, Luca Bragazza, Björn Erhagen, Juul Limpens, Karsten Kalbitz |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250121670
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| Publikation (Nr.) |
 EGU/EGU2016-472.pdf |
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| Zusammenfassung |
| Northern peatlands store a large organic carbon (C) pool that is highly exposed to future
environmental changes with consequent risk of releasing enormous amounts of C. Biotic
changes in plant community structure and species abundance might have an even stronger
impact on soil organic C dynamics in peatlands than the direct effects of abiotic changes.
Therefore, a sound understanding of the impact of vegetation dynamics on C cycling will
help to better predict the response of peatlands to environmental changes. Here, we aimed to
assess the role of plant functional types (PFTs) in affecting peat decomposition in relation to
climate warming.
To this aim, we selected two peatlands at different altitude (i.e. 1300 and 1700 m asl) on
the south-eastern Alps of Italy. The two sites represent a contrast in temperature, overall
vascular plant biomass and relative ericoids abundance, with the highest biomass and
ericoids occurrence at the low latitude. Within the sites we selected 20 plots of similar
microtopographical position and general vegetation type (hummocks). All plots contained
both graminoids and ericoids and had a 100% cover of Sphagnum mosses. The plots were
subjected to four treatments (control, and three clipping treatments) in which we selectively
removed aboveground biomass of ericoids, graminoids or both to explore the contribution
of the different PFTs for soil respiration (n=5) and peat chemistry. Peat chemical
composition was determined by the analysis of C and N and their stable isotopes in
association with pyrolysis GC/MS. Soil respiration was measured after clipping
with a Licor system. Preliminary findings suggest that peat decomposition pathway
and rate depend on plant species composition and particularly on differences in
root activity between PFTs. Finally, this study underlines the importance of biotic
drivers to predict the effects of future environmental changes on peatland C cycling. |
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