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| Titel |
Upland beech trees significantly contribute to forest methane exchange |
| VerfasserIn |
Katerina Machacova, Martin Maier, Katerina Svobodova, Ellen Halaburt, Sally Haddad, Friederike Lang, Otmar Urban |
| 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 |
250131047
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| Publikation (Nr.) |
 EGU/EGU2016-11400.pdf |
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| Zusammenfassung |
| Methane (CH4) can be emitted not only from soil, but also from plants. Fluxes of CH4were
predominantly investigated in riparian herbaceous plants, whereas studies on trees,
particularly those lacking an aerenchyma, are rare. In soil produced CH4 can be taken up by
roots, transported via intercellular spaces and the aerenchyma system, or transpiration stream
to aboveground plant tissues and released to the atmosphere via lenticels or stomata.
Although CH4 might be also produced by microorganisms living in plant tissues or
photochemical processes in plants, these processes are relatively minor. It has been shown
that seedlings of European beech (Fagus sylvatica) emit CH4 from its stems despite the lack
of an aerenchyma.
Our objectives were to determine the CH4 fluxes from mature beech trees and adjacent
soil under natural field conditions, and to estimate the role of trees in the CH4exchange
within the soil-tree-atmosphere continuum.
Measurements were conducted in two mountain beech forests with different geographical
and climatic conditions (White Carpathians, Czech Republic; Black Forest, Germany). CH4
fluxes at stems (profile) and root bases level were simultaneously measured together with
soil-atmosphere fluxes using static chamber systems followed by chromatographic analysis or
continuous laser detection of CH4 concentrations.
Our study shows that mature beech trees have the ability to exchange CH4 with the
atmosphere. The beech stems emitted CH4 into the atmosphere at the White Carpathians site
in the range from 2.00 to 179 μg CH4 m−2 stem area h−1, while CH4 flux rates ranged
between -1.34 to 1.73 μg CH4 m−2 h−1 at the Black Forest site. The root bases of beech trees
from the White Carpathians released CH4 into the atmosphere (from 0.62 to 49.8 μg CH4
m−2 root area h−1), whereas a prevailing deposition was observed in the Black
Forest (from -1.21 to 0.81 μg CH4 m−2 h−1). These fluxes seem to be affected by
soil water content and its spatial heterogeneity. Compared to beech trees, forest
floor was a sink for CH4 on the both sites. The deposition rates reached -52 and
-161 μg CH4 m−2 soil area h−1 at the White Carpathians and Black Forest site,
respectively. Concluded, CH4 emissions from upland beech trees significantly contribute to
total CH4 flux and have to be counted towards the overall CH4 balance of beech
forest.
Acknowledgement
This research was financially supported by the Czech Academy of Sciences and the
German Academic Exchange Service within the project "Methane (CH4) and nitrous oxide
(N2O) emissions from Fagus sylvatica trees" (DAAD-15-03), National Programme
for Sustainability I (LO1415) and DFG project (MA 5826/2-1). We thank Marek
Jakubik for technical support and Sinikka Paulus for help by field measurements. |
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