Effects of slope morphology on airborne multispectral scanner data

Abstract

Use of remotely sensed imagery in land use and vegetation classification studies has not always taken into account the effects of topography. Whilst previous work recognises that natural variation in slope and aspect has a deleterious effect on the accuracy of pixel-by-pixel classification based on reflectance values, the cause and effect relationship has yet to be fully accounted for. This study confirms that the variation in topography has an important effect on recorded reflectance values and that such effects are not random but follow direct relationships. These relationships are dependent not only on the wavelength of the reflected radiation and the slope angle and aspect but also the break of slope. Results indicate that even at the microtopographic level, slope morphology has an appreciable effect on reflectance values measured by an airborne scanner.