HR: 1400h
AN: H53D-02 [Abstracts]
TI: * Smith, M W
EM: mark.smith@durham.ac.uk
AF: Durham University, Department of Geography
Durham University Science Laboratories
South Road
, Durham, DH1 3LE, United Kingdom
AU: Bracken, L J
EM: l.j.bracken@durham.ac.uk
AF: Durham University, Department of Geography
Durham University Science Laboratories
South Road
, Durham, DH1 3LE, United Kingdom
AU: Cox, N J
EM: n.j.cox@durham.ac.uk
AF: Durham University, Department of Geography
Durham University Science Laboratories
South Road
, Durham, DH1 3LE, United Kingdom
AB:
In regions where Hortonian overland flow dominates, soil surface morphology will demonstrate systematic
changes as the volume of overland flow increases with distance downslope. Overland flow gathers in
depressions and eventually begins to form flow concentrations and rills. Distinct zones of similar soil surface
morphology may be easily identified on a hillslope where vegetation cover is limited (Bracken and Kirkby, 2005).
Each zone will differ in hydraulic resistance to overland flow and the degree of flow concentration. This in turn will
determine the velocity at which flow is routed downslope. The spatial configurations of such zones across a
hillslope will influence transfer of runoff from hillslope to river channel. This paper presents results from a study
which uses laser-scanned surfaces to examine the influence on soil surface roughness on flow concentration
and velocity at both the plot and hillslope scale. In semi-arid environments, where flood events are often both
flashy and localised (Bull et al., 2000), this approach offers an appreciation of the gradual development of
connected flowpaths over a hillslope during a rainstorm. This develops our ability to predict water inputs into
ephemeral channels and, therefore, can potentially be applied to help predict the generation of flood waves
through semi-arid catchments.
DE: 1804 Catchment
DE: 1826 Geomorphology: hillslope (1625)
DE: 1838 Infiltration
DE: 1850 Overland flow
SC: Hydrology [H]
MN: 2007 Joint Assembly