Evaluation of the Changes of Soil Salinity in South East of Sabzevar Arid Zones by Using the Remote Sensing Datum and GIS

Destruction of lands and vegetations which is named desertification in international associations known one of the most important difficulties for human activities. Sosils Salinity is a most important reason in form and extension of deserts. In this research with the aim of evaluation of the changes of salinity of soil which related in deserts in Sabzevar area the measurement of this area is 410000 hectares after geometrical correction, are used TM landsat digital datum of 13 May, 2001 and 20 April 1987 periods as the most important tools. So between many composite bands, indexes constitution and analysis of main factors the FCC 521 band as the best band of three-band composite is selected as technique of the work. Then to take many soil samples of area and testing in laboratory with using supervised classification method with the most probability the salinity maps of area for the both periods of time are drawn and analyzed. The analyses of salinity maps and interpretation of satellite images show don’t changes in extension of non - salinity lands in area. However; increasing low - salinity lands in area the semi - salinity lands decrease gradually.