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| Titel |
Effect of Leaf Litter Diversity on Dissolved Organic Matter Export in a Deciduous Forest Soil |
| VerfasserIn |
A. Scheibe, V. Eißfeller, C. Langenbruch, J. Seven, G. Gleixner |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250066084
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| Zusammenfassung |
| We investigated sources and fate of dissolved organic matter (DOM) in soils in order to
understand the effect of tree diversity on below ground processes. We established a leaf litter
exchange experiment in the National Park Hainich (Thuringia, Germany) in December
2008. Labeled (13C) and unlabeled leaf litter of beach (Fagus sylvatica) and ash
(Fraxinus excelsior) were exposed to study the decomposition process. Soil water
was collected biweekly with glass suction plates (1Â μm pore size, UMS, Munich,
Germany) in 5 cm soil depth and pH, conductivity, DOC and anions (Cl-, NO3-,
NO2-, PO43-, SO42-, F-) were determined. The 13DOC values were measured
using high performance liquid chromatography - isotope ratio mass spectrometry
(HPLC-IRMS).
The values of conductivity and pH in the soil water indicate slower decomposition
processes for leaf litter of beech in comparison to ash leaf litter. The conductivity was
correlated with the Cl- ion during the first spring, which suggests the export of carbon due to
leaching processes. However during the summer the conductivity correlated with the NO3-
ions, which indicates mineralization as driving process.
Surprisingly, the contribution of litter 13C into the dissolved carbon pool was very low.
The highest contribution with up to 8.6% DOC labeled by ash litter derived carbon was
found in the first 3 month of application. However, in the mean only 1.2% and
2.6% of DOC was labeled by carbon of the beech and ash litter, respectively. This
represents in total only up to 0.41% of labeled litter carbon that was added. The higher
percentages of ash litter derived 13C in DOM of soil water compared to beech indicates
a positive effect of litter quality on decomposition. However, we did not find a
faster decomposition or higher ash litter derived carbon export in mixed (ash and
beech litter) treatments, which would indicate food selection or biodiversity effects. |
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