Recent Trends in Soil Salinity Appraisal and Management

A comprehensive understanding on soil salinity appraisal is prerequisite for development and execution of rehabilitation programs and productive agricultural use of salt-affected soil (SAS). Indian agriculture since pre-independent era has been providing top priorities to rehabilitate SAS for considering the welfare of farming communities. Broadly SAS are categorized into: saline which are loaded with soluble electrolytes; sodic soil carries disproportionately high levels of sodium relative to calcium and magnesium in soil exchange sites and soil solution with alkaline reaction; and saline-sodic soil with twin problems of sodicity and salinity; and special categories SAS having regional occurrence. Saline and sodic underground water, rainfall deficit and high evapotranspiration demand for crops are usually associated threats with SAS. Therefore, intensive and temporal survey, delineation and mapping are required for capturing the extent of salinity problem. Here, we tried to highlight classification and behaviours of SAS, threat associated with these soils, methodological appraisal for salinity assessment both conventional laboratory chemical analysis and standardized rapid and non-destructive methods like EM-38 based on electromagnetic geophysical tools, time domain reflectometry, resistivity survey, hyper-spectral remote sensing, etc. Besides, several technological options, viz., need of amendment for rehabilitation of sodic soils and agro-technologies for managing salinity are described to combat salinity and sustain crop production.