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| Titel |
Plant-mediated CH4 transport and contribution of photosynthates to methanogenesis at a boreal mire: a 14C pulse-labeling study |
| VerfasserIn |
M. Dorodnikov, K.-H. Knorr, Y. Kuzyakov, M. Wilmking |
| 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 ; 8, no. 8 ; Nr. 8, no. 8 (2011-08-29), S.2365-2375 |
| Datensatznummer |
250006089
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| Publikation (Nr.) |
 copernicus.org/bg-8-2365-2011.pdf |
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| Zusammenfassung |
| Plant-mediated methane (CH4) transport and the contribution of recent
photosynthates to methanogenesis were studied on two dominating vascular
plant species – Eriophorum vaginatum and Scheuchzeria palustris – at three types of microrelief forms (hummocks –
E. hummocks, lawns – E. lawns and hollows – S. hollows) of a boreal natural
minerogenic, oligotrophic fen in Eastern Finland. 14C-pulse labeling of
mesocosms with shoots isolated from entire belowground peat under controlled
conditions allowed estimation of plant-mediated CH4 flux and
contribution of recent (14C) photosynthates to total CH4. The
results showed (i) CH4 flux increased in the order E. hummocks ≤ E. lawns < S. hollows corresponding to the increasing water table level at the
relief microforms as adjusted to field conditions. (ii) Plant-mediated
CH4 flux accounted for 38, 31 and 51 % of total CH4 at E. hummocks, E. lawns and S. hollows, respectively. (iii) Contribution of recent
photosynthates to methanogenesis accounted for 0.03 % for E. hummocks,
0.06 % for E. lawns and 0.13 % for S.hollows of assimilated 14C. Thus,
microsites with S. palustris were characterized by higher rates of transported CH4
from the peat column to the atmosphere when compared to E. vaginatum of drier lawns and
hummocks. Contribution of recent photosynthates to methanogenesis was
dependent on the plant biomass within-species level (E. vaginatum at hummocks and lawns)
but was not observed between species: smaller S. palustris had higher flux of
14CH4 as compared to larger E. vaginatum. Therefore, for the assessment of
CH4 dynamics over meso- and macroscale as well as for the implication
and development of the modeling of CH4 fluxes, it is necessary to
account for plant species-specific differences in CH4 production,
consumption and transport and the attribution of those species to
topographic forms of microrelief. |
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