Channel–floodplain connectivity during an extreme flood event : implications for sediment erosion, deposition, and delivery

Auteur(s) et Affiliation(s)

CROKE, J.

Australian Rivers Inst., Griffith Univ., Queensland, Nathan, Australie

FRYIRS, K.

Dept. of Environment and Geography, Macquarie Univ., Sydney, Australie

THOMPSON, C.

Integrated Center for Catchment Management (ICaM), Australian National Univ., Acton, Australie

Australian Rivers Inst., Griffith Univ., Queensland, Nathan, Australie

Description :
The term connectivity is emerging as an innovative component of catchment erosion modeling studies. However, considerable confusion remains regarding its definition and quantification. The catastrophic flood of January 2011 in the Lockyer valley, southeast Queensland, Australia provides an opportunity to examine the connection between channels and floodplains and to determine how these dynamics operate under high flow regimes. High resolution aerial photographs and multi-temporal LiDAR digital elevation models (DEMs), coupled with hydrological modeling, are used to assess both the nature of hydrologic and sedimentological connectivity and their dominant controls. Longitudinal variations in flood inundation extent led to the identification of 9 reaches which displayed varying channel–floodplain connectivity. The results highlight the need to carefully consider non-linear changes in key variables such as channel capacity and flood conveyance in the development of a quantitative connectivity index.

Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2013, vol. 38, n°. 12, p. 1444-1456, nombre de pages : 13, Références bibliographiques : 2 p.

Date :
2013

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

Langue :
Français