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| Titel |
Quantification of the clay mineralogy of a typical Vertic Planosol in south-western Ethiopia: impact on soil formation hypotheses |
| VerfasserIn |
Mathijs Dumon, Boris Capon, Christophe Detavernier, Eric Van Ranst |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250072768
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| Zusammenfassung |
| Planosols, characterised by a surface horizon abruptly overlying a dense subsoil, are a very
common soil type in Ethiopia. The origin of the abrupt textural change is still often debated in
literature. One of the processes frequently put forward to explain the coarse textured material
in the topsoil, is ‘ferrolysis’: an oxidation-reduction sequence driven by bacterial
decomposition of soil organic matter, resulting in the destruction of open 2:1 clay minerals.
Recent studies of representative profiles of Vertic Planosols in south-western Ethiopia
indicate that these these soils are composed of a weathered volcanic ash layer deposited on
top of a deflated vertic subsoil, which refutes the ferrolysis hypothesis. To strengthen the
geogenetic origin of these profiles, a quantitative mineralogical analysis of the clay fraction
was undertaken.
Textural analysis of the fine earth fraction ( |
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