The mapping of desert alluvial soils through the use of remote sensing and GIS techniques

Originating from the uplands of semi-arid regions, streams and rivers transport sediments downslope. Steep changes in the gradient of the land, it is widely believed, forced the deposition of sediments over vast regions of the desert plain through time. Various studies indicate that these sediments, or alluvium, may occupy as much as 70 percent of the surrounding desert basins (Merifield, 1987). Interestingly, since antiquity a number of soils in these areas have been known to be agriculturally productive (Encyclopedia Britannica, 1978). Many of the potientially fertile soils in semi-arid regions, particularly in underdeveloped regions, remain unmapped. Less expensively, improved digital classification of satellite imagery could expedite the process of generating vital soil data. Methods of enhancing the digital classification of soils in a semi-arid environment are investigated. Specifically, image classification techniques are combined with the use of ancillary data and then discussed based of its ability to discriminate semi-arid soils. Results may be observed in map format.