Exploratory study of the relationship between tropical forest regeneration stages and SIR-C L and C data

Abstract In this article, the relationship between secondary forest regrowth stage and SIR-C SAR data is assessed, for an area located near to the Tapajos National Forest, south of Para State, in the Amazon region. These regeneration stages are mapped by making use of a consecutive annual sequence of Landsat TM (Thematic Mapper) images. Using this map as a mask over the radar images, the tonal means (expressed in dB) and coefficient of variation (CV) for several second-growth succession stages classes are calculated. It is shown that the discrimination between regeneration stages is difficult when individual ″small areas are used, but this discrimination might be possible when L-band means over a “large area are computed. In particular, the LHV band seems to carry more information. The maximum difference of means among classes occurred in this band and it is of about 5 dB. The CV appeared to be less well suited than the mean value for regeneration stage discrimination, although some discrimination among early stages of regeneration may be possible using this measure at L-band.