Models for imaginary part of dielectric constant of moisture and salt soil

Abstract

This work had presented the expressions for imaginary part of dielectric constant of moisture salt soil at low and high frequencies respectively, which is a function of 1) soil water content and 2) soil salt content. This result makes it possible to retrieve the soil salt content that is often useful for monitoring plantation's salinization in inland countries. To establish the relationship between imaginary part and soil physical characters, namely soil moisture and salt content, the relationship between imaginary part of dielectric constant /spl epsiv/ and soil bulk conductivity /spl sigma//sub a/ relationship between soil bulk conductivity /spl sigma//sub a/, and conductivity of soil solution /spl sigma//sub w/, relationship between conductivity of soil solution /spl sigma//sub w/ and soil solution concentration, and relationship between soil solution concentration and soil salt content have been established gradually. According to these correlations (/spl epsiv/ /spl sim/ /spl sigma//sub a/ /spl sim/ /spl sigma//sub w/ /spl sim/ S/sub M./ /spl sim/ S), the expressions for /spl epsiv/ /spl sim/ S and M, had been directly made and simplified as approximations with four free parameters at low frequencies or with five free parameters at high frequencies. The two models for low and high frequencies had been examined and calibrated by 150 soil samples that had been watered and salinized distinctly in lab and a good agreement with the measured data had been achieved with the coefficients between the calculated and the measured greater than 0.9.