A modeling study on the relationship between heavy metal contamination in soil and the amplitude properties of georadar electromagnetic waves

In this study, the amplitude data of geo-radar electromagnetic (EM) waves were extracted using EM wave property analysis software, and the variation relationship between the heavy metal concentrations measured in the field and the geo-radar EM wave was analyzed to construct the characteristic function of geo-radar signal waves and heavy metal pollution. Heavy metal concentrations were obtained through inversion and compared with the measured heavy metal concentrations to further explore the feasibility of inversion by geo-radar signal waves. The variations of electromagnetic wave amplitude properties with burial depth on different profiles were analyzed, and it was concluded that the variation of the mean absolute amplitude for geo-radar electromagnetic waves was most consistent with the variation in burial depth. The trend of mean absolute amplitude was found to have a significant correlation coefficient (0.8329). The root mean square (RMS) amplitude fluctuated between 2000 and 3000 as the concentration stayed in the range of 250–300 mg/kg and stabilized around 1000 in the concentration range of 50–100 mg/kg. The mean absolute amplitude showed a similar trend to the RMS amplitude, displaying decreasing amplitude within the concentration range of 50–100 mg/kg. The characteristic function of heavy metal pollution concentration and EM wave amplitude was expressed as \(c=-0.00006\times {{F}_{{\text{a}}}}^{2}\text{+0.36}\times {F}_{{\text{a}}}-247.52\), which could be used to predict the actual heavy metal concentration changes through the changes in mean absolute amplitude. This provides a theoretical foundation for developing a model of the relationship between heavy metal pollution concentrations and electromagnetic wave amplitudes.