Remote sensing application of soil salinization based on multi-source images

摘要

The aim of this study was to test a method for regional-scale soil salinization mapping in arid area using multi-source images, SPOT and ASTER, and digital elevation data. Two databases were used for the study. The first one was purely ASTER data, while in the second database the ASTER data was complemented with a SPOT data. To extract salinity information in effect, layers of DEM, slope, and aspect were integrated into two databases. The performance of these two databases when employed to derive soil salinization information was compared. Based on the analysis of field-derived data, it was concluded that soil salinity was consistent with land surface features. Two databases were then further processed using minimum noise fraction, pixel purity index, and then classified using spectral angle mapper. The thematic map of soil salinization was got, ultimately. The accuracy assessment showed that the SPOT-ASTER-DEM database got better result than that of ASTER. And the method is resultful for rapid assessment of soil salinization, especially in remote arid area where conventional methods are restricted.