Annual fossil organic carbon delivery due to mechanical and chemical weathering of marly badlands areas

Auteur(s) et Affiliation(s)

GRAZ, Y.

Univ. Orléans, Univ. François Rabelais -Tours, CNRS/INSU Inst. des Sciences de la Terre Orléans - UMR 7327, Orléans, France

DI-GIOVANNI, C.

Univ. Orléans, Univ. François Rabelais -Tours, CNRS/INSU Inst. des Sciences de la Terre Orléans - UMR 7327, Orléans, France

COPARD, Y.

UMR CNRS 6143 M2C, Univ. Rouen, Dep. Sciences de la Terre, Mont Saint-Aignan, France

MATHYS, N.

Cemagref Grenoble, U.R. Erosion Torrentielle, Neige et Avalanches, Saint Martin d'Hères, France

CRAS, A.

Lab. Hydrogéologie, Fac. des Sciences, Univ., Avignon, France

MARC, V.

Lab. Hydrogéologie, Fac. des Sciences, Univ., Avignon, France

Description :
This work focuses on fossil organic carbon (FOC) fluxes due to chemical and mechanical weathering of marls in 2 experimental watersheds with typical badlands geomorphology (Draix watersheds, Laval and Moulin, Alpes de Haute Provence, France). A classical geochemical analysis (Rock-Eval 6 pyrolysis) was used to characterize organic matter in the studied samples (bedrocks, soil litters and riverine particles). FOC fluxes were estimated by monitoring the particulate (1985-2005 period) and dissolved (year 2002) exports at the outlet of the watersheds. Results show that FOC delivery is mainly driven by mechanical weathering. These high FOC fluxes from badlands are similar to those observed in tectonically active mountain catchments. At a global scale, these findings suggest that erosion of badlands may contribute significantly to the transfer of FOC from continental surfaces to depositional environments.

Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2012, vol. 37, n°. 12, p. 1263-1271, nombre de pages : 9, Références bibliographiques : 2 p.

Date :
2012

Editeur :
Pays édition : Royaume-Uni, Chichester, Wiley

Langue :
Anglais