Mapping Soil Surface Salinity using the Landsat ETM+ Digital Data in the South of Ahvaz

Soil salinity and salinization are destructive phenomena and limiting factors for agricultural development. Therefore، it is necessary to monitor and mange salinity. Identification of saline soils and production of saline soils maps are the first steps for their management. The objective of this study was to achieve a map of saline soils of the south of Ahvaz using ETM+ images. Soil sampling from 0-15 cm was accomplished using visual interpretations and differences in spectral reflection of various phenomena. Electrical conductivity (EC) was measured in soil paste. Spectral values of each sample were obtained in different bands and the relationship between spectral values and samples electrical conductivity was analyzed by determining correlated bands and selecting desirable bands for contributing to the model. The results showed that the correlation between electrical conductivity values with B4، B2 bands، brightness and SAVI was significant at 1% level. Using the correlation between satellite data (Landsat ETM+ 2010) and numerical value of soil salinity، salinity maps were produced in GIS. Finally، a salinity map was prepared using a multiple variable regression model. The accuracy of the produced map by electrical conductivity values showed that the correlation method in mapping soil salinity can be recommended.