Effect of salinity on the microwave emission from dry soil surface

ABSTRACT<br /> The goal of this study was to apply the concept of passive microwave remote sensing to find the data set of microwave brightness temperatures of the dry soil surface as a function of actual salinity factors that influence the dielectric properties of the soil.<br /> <br /> <br /> <br /> From the agricultural point of view, salinity factor refers to the state of accumulation of the soluble salts in the soil. In many area, this factor limiting plant growth (such as sodium chloride).<br /> The measurements of the dielectric permittivity were conducted using shorted-circuited-waveguide technique at L-and C-band microwave frequencies (i.e. 1.4GHz and 5GHz, respectively). The dielectric properties of the salted soil samples were investigated at a thermodynamic temperature of 20.4 c .<br /> The results show that the frequency of 1.4GHz (L-band) is more effective frequency for study of the penetration depth of the soil surface. Also the vertical polarized microwave signals is preferred to study the variation of the emission characteristics of the dry soil with respect to the salinity by using the microwave radiometric remote sensing techniques especially at low microwave frequency.