Dielectric properties of salt-affected soils

A detailed laboratory experiment was conducted on three soils of different textures viz., sand, sandy clay loam and clay to study the influence of soil salinity and sodicity on the complex dielectric behaviour of soils as a function of volumetric soil moisture using an L-band (1 ·25 GHz) dielectric probe. The results revealed that soil salinity has no influence on the real part of the dielectric constant (ϵ') whereas, the imaginary part (ϵ'') is dependent and increases with increase in salinity for all the soils considered. It was found that the real part is more dependent on soil moisture and imaginary part on soil salinity. The sodicity of a soil has no influence either on real part or imaginary part. This study shows L-band (1·25 GHz) microwave response to soil salinity. It also demonstrates the possibility of separating saline soils from sodic soils at L-band frequencies under moist soil conditions.