HR: 1330h
AN: H42C-1103 [PDF]
TI: Digital elevation models and the characterisation of catchments over different grid scales
AU: * Hancock, G R
EM: gggh@alinga.newcastle.edu.au
AF: School of Environmental and Life Sciences, The University of Newcastle, University Drive, Callaghan,
NSW 2308
Australia
AB:
Well known geomorphological descriptors and statistics are examined for their ability to differentiate between catchments
with spatially varying geology, size and shape. The effect of digital elevation model grid resolution on these statistics is
also examined. Results demonstrate that catchment descriptors such as the area-slope relationship, cumulative area
distribution and hypsometric curve can differentiate between catchments with different geology and resultant morphology, but
catchment network statistics are insensitive to differences in geology. Examination of the effects of digital elevation model
grid scale demonstrates that while considerable catchment information can be gained at digital elevation grids greater than
10m by 10m, considerable hillslope and hydrological detail can be lost. Consequently, caution is needed when deciding on an
appropriate grid resolution as well as the interpretation and analysis of catchment properties at grid scales greater than
that for optimal hillslope and area aggregation definition.
DE: 1815 Erosion and sedimentation
DE: 1824 Geomorphology (1625)
SC: Hydrology [H]
MN: 2003 Fall Meeting