盐渍土介电特性及模型改进研究

基于控制试验对配制的具有不同含水量和含盐量的土壤样本进行介电特征量测和分析，同时结合Stogryn盐水介电模型和土壤溶液离子浓度、电导率、含水量和含盐量等参数对介电常数虚部的影响，将饱和度这个关键参量引入盐渍土介电模型中，提高盐渍土介电模型模拟精度。结果表明：①当土壤体积含水量较低时，土壤含盐量对介电常数的实部和虚部均未产生明显的作用。当土壤体积含水量较高时，介电常数实部则随着土壤含盐量的增加呈逐渐下降趋势，介电常数虚部以增加态势为主;②修正后的盐渍土介电模型可以较好地刻画介电常数变化特征。此外，将修正后的模型在白银采样点进行验证，同样取得较好的模拟结果，表明修正后的盐渍土介电模型对不同土壤类型具有一定的适用性。

Dielectric Properties of Saline Soil and an Improved Dielectric Model

The measurement and analysis of the dielectric constant of soil samples with different moisture and salinity are achieved based control experiment. The saturation is introduced to the dielectric model of salinity soil to improve simulation accuracy by taking the Stogryn model and the influence of soil solution ion concentration, conductivity, moisture content, and salt content for dielectric constant imaginary part into consideration. The results indicate that the soil salt content has little influence on both real part and imaginary part of dielectric constant when soil volumetric moisture content is low, while soil volumetric moisture content is high, the real part of the dielectric constant decreases with the increase of soil salt content, and the imaginary part of the dielectric constant increases. The improved dielectric model of salinity soil can well reveal the changes of dielectric constant, and it is also having a great effect in Baiyin soil samples. That is to say, the improved dielectric model can apply to different soil types.