Remote Determination of Inhomogeneous Moisture Distribution in the Soil Root Layer using Mathematical Model of Complex Permittivity

The article presents a study of the remote determination of the inhomogeneous moisture distribution in the root layer of the soil using a mathematical model of the complex permittivity. The general attention is paid to the analysis of reflections of the electromagnetic wave of horizontal polarization from the root soil layer, taking into account its heterogeneous moisture profile. As a result of numerical calculations, it was found that when developing algorithms for remote methods for determining humidity, it is critical to observe models that reflect the heterogeneous distribution of moisture throughout the depth of the soil layer. As the part of the solution of the two-point boundary problem of the interaction of an electromagnetic wave with the soil, it was demonstrated that the level of reflection of the waves decreases significantly when the moisture profile changes according to the parabolic law, which most accurately corresponds to real conditions after irrigation or rain. The results obtained emphasize the importance of considering the spatial heterogeneity of moisture in order to improve the accuracy of remote measurements and monitoring of soil condition.