Advancing understanding of runoff and sediment transfers in agricultural catchments through simultaneous observations across scales

Auteur(s) et Affiliation(s)



Description :
A multi-scale dataset of 17 rainfall events collected simultaneously at 4 spatial scales within a small agricultural catchment in 2005-2006 is presented. Analysis using exploratory techniques and a two-step, zero-inflated lognormal mixed-effects regression model, has demonstrated that event responses, and event response characteristics representing runoff and sediment peaks and area-normalized yields, are scale dependent, and hence cannot be transferred directly between scales. Runoff and sediment yields increase as scale increases, and it is proposed that this effect, which differs from that observed in the few other studies of scale effects undertaken, is due to increasing connectivity within the catchment, and the dominance of preferential flow pathways including through macropores and field drains. The processes contributing to scale dependence in the data, and the possibility that certain processes dominate at particular scales, are discussed.


Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2011, vol. 36, n°. 13, p. 1749-1760, nombre de pages : 12, Références bibliographiques : 59 ref.

Date :
2011

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