不同含水量的土壤会产生不同的偏振态,其与波长、土壤表面的结构、内部的构成、以及入射的角度密切相关。根据Kodis粗糙表面的散射理论,推导了不同湿度土壤表面的偏振度与入射天顶角和观测天顶角以及等效折射率的关系,并用野外地物偏振辐射计和地面多波段CCD相机实测了红壤的偏振反射数据,并将其与理论计算结果相对照,初步总结出不同含水量红壤的偏振特性变化规律。研究土壤偏振度与含水量以及入射天顶角、观测天顶角的关系,对于卫星农业遥感有重要的意义。
Different state of polarization can be generated by different soil moisture, which relates closely to the wavelength, the roughness of the soil, the component of soil, and the incident zenith angle. According to Kodis'theory for scattering by a rough surface, a simple formula that relates the degree of polarization of soil to incident zenith angle, viewing angle and refractive index is obtained. Polarized reflectance data of different moisture red soil is collected with a polarimetric instrument and compared with the calculated results. Preliminary results of the change in degree of polarization for red soil with different moisture are presented. The results are significant for satellite agricultural remote sensing.