Analysis Of Influencing Factors Of Polarized Thermal Radiation Of Soil

Being an important composite of the nature, soil has great influence on the ecological system and human life. The study of soil's polarized thermal radiation characteristics is significant to the monitoring soil information by thermal infrared remote sensing.Many measurements of the polarized thermal radiation characteristics have been carried out by researchers However, there is few studies on the polarized thermal radiation of soil. Hence, it is necessary to carry out the exploration of the polarized thermal radiation characteristics of soil to provide important foundation for the evolution of thermal infrared remote sensing.The polarized thermal radiation of soil from different detection angles, azimuth angles, polarization angles, channels, agrotypes and soil water content were measured by using BPDF measurement platform, thermal infrared radiometer, thermal infrared polarizer. An orthogonal experiment was used to analyze the influence of various factors and the interaction among the factors on the polarized thermal infrared characteristics of soil.Firstly, we made the qualitative analysis on the influence of five factors, including detection angle, azimuth angle, polarization angle, channel and agrotype, on the polarized radiation brightness of soil. The results of single factor analysis showed as followings:1. The polarized radiation brightness and polarized brightness temperature would change in a wide range as the change of detection angle and agrotype separately.2. The polarized radiation brightness and polarized brightness temperature just changed in a small scale among different polarization angles and azimuth angles.3. The order of channels in polarized radiation brightness was CH1>CH3>CH4>CH2, but there was no obvious difference among channels in polarized brightness temperature.Secondly, we made quantitative analysis about the influence of the factors (detection angle, azimuth angle, polarization angle, channel, agrotype and soil water content) and their interactions on the polarized radiation brightness of soil. The results were displayed below:4. The channel, agrotype, soil moisture content, interaction between azimuth angle and soil content, interaction between agrotype and soil moisture content had the extremely significant effect on the polarized thermal infrared brightness and brightness temperature of soil, which the significance was smaller than 0.1%.5. The interaction between channel and agrotype had the extremely significant effect on the polarized radiation brightness, but not significant effect on the polarized brightness temperature.The thesis combined the multi-angle information, multi-band information and polarization information in the thermal infrared wavelengths together, thus it can provide important foundation to the theory of polarized thermal infrared remote sensing. A new technical means of the soil classification by remote sensing and parameter inversion of soil may be developed.