Key words: DEM, Surface Roughness, Slope, Tangential Curvature, Incision, Gilgit-Baltistan.
Shuttle Radar Topographic Mission-Digital Elevation Model (SRTM DEM) with a spatial resolution of 90 m was used for the generation of slope gradients (in degrees), aspects, tangential curvature, hillshade, flat area and surface area maps.
Regional topographic features such as UHF and MKT are E-W oriented while the RSF is SW-NE oriented and clearly explains the higher slopes, high surface roughness values and positive tangential curvature values.
Using GIS data exploration techniques, nine data layers (percent slope, slope length, profile curvature, tangential curvature, mean curvature, flow accumulation, flow line density, distance to troughs, and distance to summits) were extracted from U.
These elements can be described by geomorphic forms of hillslope, which are defined by their slope curvatures: profile curvature and tangential curvature (Chorley et al.
profile curvature, tangential curvature, and flow accumulation) generated from the 10-m (10.
The predictive model statement used the continuous quantitative variables elevation, slope, aspect, tangential curvature, plan curvature, profile curvature, In upslope contributing area (Inca), and the categorical factor geology to predict Toowoomba dominant PPF.
These evidence layer maps were the Ipswich 1:250000 geology map, the slope map categorised into 16 classes, the DEM in 15 classes, a drainage area (ln ca) map in 13 classes, and the tangential curvature map in 5 classes.
The classification tree obtained using the continuous quantitative variables elevation, slope, aspect, tangential curvature, plan curvature, profile curvature, natural log of the upslope contributing area (Inca), and the categorical factor geology to predict Toowoomba dominant PPF had 116 nodes.
846 = construction: factor (geology) 58770/ +elevation+slope(%) + In ca+aspect+profile curvature+ 20650 tangential curvature Variables actually used in tree 36 2.
Of the DEM-derived terrain attributes, only slope (%), Inca, aspect, profile curvature, and tangential curvature are used to build the tree when it is pruned to 55 or 36 terminal nodes.