ADVANCES IN SOIL SALINITY DETECTION IN ARID AND SEMI- ARID REGIONS USING SALINITY AND VEGETATION INDICES

Abstract

Soil salinization as a result of natural or of human-induces processes is a serious global-scale problem. Salinization is a major reason for soil resources degradation and declining of soil fertility. From an ecological and economic point of view it is extremely important to follow the occurrence and distribution of soil salinity as well as the intensity of the process. Several studies and efforts in assessing and controlling soil salinity have been made. Remote sensing techniques are widely used to detect and map the salt-affected areas. The indices used in this research are the normalized differential vegetation index (NDVI), normalized difference salinity index (NDSI) and modified soil adjust vegetation Index (MSAVI). MSAVI was found to be effective in discriminating the plants under severe and moderate conditions of soil salinity as well as under non-saline conditions. Temporal trend analysis technique was carried out to detect significant changes in the soil verses vegetation conditions. The obtained results showed that the studied area is mostly covered by field crops where, NDVI values were ranging between 0 and 0.82 and MSAVI ranging from 0.02 to 0.70. The NDSI values, however, showed the land salinity classes, as they were fluctuated from 0.01 to 0.89.