Ground and airborne radiometry over intertidal surfaces: Waveband selection for cover classification

Airborne remote sensing using a Compact Airborne Spectrographic Imager (CASI) has been used to map intertidal surfaces (vegetated and unvegetated at low tide) on the East Coast of England for the Land-Ocean Interaction Study (LOIS). This paper describes how ground radiometry with a Spectron spectroradiometer has been used to examine spectra for a range of surfaces and to compare different CASI bandsets for discrimination of different classes of intertidal vegetation and sediments. CASI in spatial mode records data in up to 14 programmable wavebands in the visible and near-infrared spectral range. Different CASI bandsets have been devised for different purposes (some within this project with the aid of Spectron data). A range of these bandsets are compared on simulated CASI data derived from Spectron ground radiometry. Principal component analysis and discriminant analysis show that these CASI bandsets are capable of separating spectra from 10 key surfaces, but that the various bandsets differ little in their effectiveness and that precise waveband selection is not critical.