Study on the Extraction of Saline Soil Information in Arid Area Based on Multiple Source Data

Abstract

Soil salinization has severely threatened the inner stability and the sustainable development of oasis in arid areas,so extracting the saline soil information rapidly based on remote sensing and mastering its spatial distribution are of important practical significance.In this article,taking the Kuqa oasis as the example,TM image collected on August 2001 and Radarsat image collected on Mar 2001 were used.The approach of effective remote-sensing information extraction for saline soil was discussed.The mechanism and characteristics of saline soil and other objects was analyzed to find the possibility of extracting saline soil from the background.The analysis was focused that the radar-band as a band to join the six bands of ETM together was taken to perform the principal component transformation to extract the saline soil information.The research shows that K-L-5 is the best band to extract severe saline soil information,TM1 is the best band to differentiate saline soil information with the salt-tolerant vegetation of Hongliu and the mixed water body and vegetation information can be separated by the index of MNDWI and NDVI.Then,based on the analysis,a simple model of decision tree was applied to extracting saline soil information.Finally,the results were checked by statistical accuracy assessment.The results suggest that the model of decision tree was simple and effective and the precision of this approach was very high,so it was an effective method for monitoring saline soil changes in arid area.It also showed that the separability between the saline soils and other classes was increased due to the participation of radar band,and an effective way was provided to extract saline soils information using radar images.