The value of ground resolution, spectral range and stereoscopy of satellite imagery for land system and land-use mapping of the humid tropics

Abstract

The quality of SPOT imagery of the humid tropics is variable: frequently only the infrared band is usable. The following statistical conclusions were drawn from a comparison of SPOT and Landsat-TM imagery of Belize: (1) land systems, but not often land facets, can be demarcated; (2) where the quality is good, stereoscopic imagery is preferred for demarcating land systems; (3) after stereoscopy, spectral range appeared more important than ground resolution. Landsat-TM and the two SPOT modes could be used to demarcate plantation agriculture with an overall accuracy greater than 90 per cent, and there was no significant difference between them. Smallholder agriculture was demarcated significantly less reliably (70–90 per cent overall accuracy), for which the SPOT panchromatic mode was found to be more reliable than Landsat-TM at the 99 per cent probability level, but not significantly better than the SPOT multi-spectral mode. Visual interpretation was more reliable than automated classification for demarcating largeholder agriculture.