GEOMORPHOLOGICAL SIGNATURES - CLASSIFICATION OF AGGREGATED SLOPE UNITOBJECTS FROM DIGITAL ELEVATION AND REMOTE-SENSING DATA

The concept of a geomorphological signature is developed for classifyi ng and mapping slope units with an automated procedure for analysing d igital elevation and remote sensing data. Slope units are extracted fr om a digital elevation model (DEM) using a break of slope rule on down slope profiles. Each slope unit is an aggregated object of contiguous pixels and is summarized with five suites of variables: shape, topogra phy, topographic variability, spectral characteristics, and variabilit y in spectral characteristics. The variables are derived from the DEM and a corresponding SPOT satellite image. A ten-class scheme is used t o classify slope units for a study area in southwest Yukon, Canada. Di scriminant analysis results show the power of various combinations of variables to distinguish the classes, with a maximum classification ac curacy of 90 per cent. Training signatures are employed for classifyin g the entire study area to produce a map with 88.5 per cent accuracy. The study shows that generating extensive geomorphological signatures for aggregated slope unit objects is a valuable exercise for discrimin ation and mapping. (C) 1998 John Wiley & Sons, Ltd.