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| Titel |
Carbon sequestration in deep ploughed Luvisols and Podzols of Northern Germany |
| VerfasserIn |
Viridiana Alcántara, Axel Don, Rolf Nieder, Reinhard Well |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250095299
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| Publikation (Nr.) |
 EGU/EGU2014-10748.pdf |
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| Zusammenfassung |
| Research on carbon sequestration in arable soils up to now has mainly focused on
reduced and no-tillage systems even though the effects on soil carbon stocks are
marginal. This study addresses the long-term effects of deep ploughing. We are
sampling five Luvisols and five Podzols under agriculture as well as five Podzols under
forest in Northern Germany, which were deep ploughed (50 to 90 cm depth) in the
1960s. Adjacent equally managed, but conventionally ploughed (approx. 30 cm
depth) subplots are used as a reference respectively. At each site two subplots of
20 by 40 meters, we collect samples from different depths of a soil profile (down
to 1.5 meter depth) after digging a pit. Additionally, five composite core samples
down to 1 meter depth randomly distributed over the field subplot are collected.
Soil bulk density, gravel fraction as well as organic and inorganic carbon content
will be determined to calculate organic C stocks. First results from an arable loess
soil (Haplic Luvisol) near Salzgitter, which was ploughed to 90 cm depth in 1966,
show a mean C stock of 82,5 Mg ha-1 in the deep ploughed subplot compared to
65,9 Mg ha-1 in the reference subplot. This is equal to a long-term increase of
30% in soil organic carbon due to deep ploughing, which is several times higher
than the effects of reduced ploughing or no-tillage. Moreover, we will conduct
incubation experiments to determine soil respiration and microbial biomass via substrate
induced respiration in order to elucidate the stability of the buried carbon. Further
analysis will address the stabilization mechanisms of the buried soil organic matter
including pH measurements, soil texture analysis, atomic absorption spectroscopy to
quantify pedogenic iron and aluminum oxides, cation-exchange capacity, C density
fractionation and radiocarbon dating. We will present data from the first sampling
campaigns and discuss their implications for our view on subsoil carbon stability. |
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