Lateral and depth variation of loess organic matter overprint related to rhizoliths — Revealed by lipid molecular proxies and X-ray tomography

Landscapes and soils through time

Auteur(s) et Affiliation(s)

GOCKE, M.

Dept. of Agroecosystem Research, BayCEER, Univ., Bayreuth, Allemagne

PETH, S.

Dept. of Soil Science, Univ. of Kassel, Witzenhausen, Allemagne

WIESENBERG, G.L.B.

Dept. of Geography, Univ., Zürich, Suisse

SAUER, D.

Inst. of Geography, Univ. of Technology, Dresden, Allemagne

JAHN, R.

Soil Science and Soil Protection Group, Univ., Halle, Allemagne

STAHR, K.

Inst. of Soil Science and Land Evaluation, Univ. of Hohenheim, Stuttgart, Allemagne

Description :
Although organic carbon contents are commonly very low, loess and organic matter (LOM) thereof is regarded as important terrestrial archive for vegetation and climate during deposition. However, the LOM signal is prone to contamination by OM of other age and origin than the synsedimentary vegetation. The AA. hypothesized that the influence of rhizosphere effects related to deep-rooting plants varies with depth in quality, quantity and distance to the former root. The 13 m thick late Pleistocene loess-paleosol sequence at Nussloch (near Heidelberg, SW Germany) contains rhizoliths (calcified roots) of Holocene age. With the carbonatic encrustation leading to preservation of former root deposits, rhizoliths allow for assessment of rhizosphere processes that occurred during the root's lifetime. It is shown that alkane and fatty acid proxies are suitable to identify rhizosphere extension. This was confirmed by X-ray tomography analyses.

Type de document :
Congrès

Source :
International Conference Landscapes and Soils through Time, Stuttgart, Allemagne, 2011-07-29/2011-08-01, Catena (Giessen), issn : 0341-8162, 2014, vol. 112, p. 72-85, nombre de pages : 14, Références bibliographiques : 1 p.

Date :
2014

Editeur :
Pays édition : Allemagne, Cremlingen-Destedt, Catena

Langue :
Anglais