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| Titel |
The effect of soil redistribution on soil organic carbon: an experimental study |
| VerfasserIn |
H. Hemelryck, P. Fiener, K. Oost, G. Govers, R. Merckx |
| 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 ; 7, no. 12 ; Nr. 7, no. 12 (2010-12-07), S.3971-3986 |
| Datensatznummer |
250005103
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| Publikation (Nr.) |
 copernicus.org/bg-7-3971-2010.pdf |
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| Zusammenfassung |
| Soil erosion, transport and deposition by water drastically affect the
distribution of soil organic carbon (SOC) within a landscape. Furthermore,
soil redistribution is assumed to have a large impact on the exchange of
carbon (C) between the pedosphere and the atmosphere. There is, however,
significant scientific disagreement concerning the relative importance of the
key-mechanisms at play. One of the major uncertainties concerns the fraction
of SOC that is mineralized when soil is eroded by water, from the moment when
detachment takes place until the moment when the SOC becomes protected by
burial. In this study, the changes in C-exchange between soil and atmosphere
as affected by soil redistribution processes were experimentally quantified.
During a laboratory experiment, three types of erosional events were
simulated, each of which was designed to produce a different amount of eroded
soil material with a different degree of aggregation. During a 98-day period,
CO2-efflux was measured in-situ and under field conditions on
undisturbed soils with a layer of deposited soil material. Depending on the
initial conditions of the soil and the intensity of the erosion process, a
significant fraction of eroded SOC was mineralized after deposition. However,
results also suggest that deposition produces a dense stratified layer of
sediment that caps the soil surface, leading to a decrease in SOC
decomposition in deeper soil layers. As a result, the net effect of erosion
on SOC can be smaller, depending on the functioning of the whole soil system.
In this study, soil redistribution processes contributed an additional
emission of 2 to 12% of total C contained in eroded sediment. |
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