Spectral dielectric properties of moist soils in the microwave band

Abstract

In this work, the spectral dielectric properties of moist soils in the microwave band were analyzed, using the generalized refractive mixing dielectric model (GRMDM). First, for different types of soil, all available data on dielectric constant (DC) and loss factor (LF) at zero volumetric moisture, maximum bound water fraction (MBWF) values, relating to these types of soil, as well as the static dielectric constants, relaxation times, and conductivities of both the bound soil water (BSW) and free soil water FSW were systematized in the form of a spectroscopic data base for moist soils. Second, using such a data base, the spectroscopic parameters relating to BSW and FSW were analyzed in terms of their dependence on the type of soil. In addition, for each individual soil, the dielectric spectra of both types of soil water were calculated with the use of GRMDM, in order to demonstrate the variability of those as a function of soil type. Finally, the soil water dielectric spectra together with the other parameters of the moist soil dielectric data base were applied to evaluate the dependence of moist soil emissivity on the type of soil, in the whole microwave band. From this point of view, the study conducted can be considered as a new approach, that opens perspective for carrying out both the feasibility studies and developing data processing algorithms in radiometry or radar remote sensing, using an appropriate spectroscopic data base for moist soils.