吉林西部盐碱地特性微波双频差分无损探测

Non-destructive Detection of Saline-alkali Soil based on Differential of Microwave Dual-band in Western Jilin Province

针对吉林西部盐碱地特性(内地苏打盐类型),应用车载双频段被动微波遥感系统,对不同盐碱状态的4个裸盐碱区进行双极化多角度微波辐射无损探测。基于多角度双频率双极化的观测数据优势,选择逼近式迭代算法来反演其介电常数虚部,Dobson模型反演介电常数实部。在此基础上,应用双频差分法研究了该区域盐碱地介电特性与含水量、含盐量的关系。双频差分结果表明:实部双频差分与盐碱土含水量呈线性关系,相关系数为0.9996;虚部双频差分与含盐量呈线性关系,相关系数为0.9977。这为应用被动微波遥感定量反演盐碱地特性(含水量、含盐量)奠定了理论基础。

According to characteristics of soil salinization in the western Jilin province, four regions are selected as study areas and these regions are non-destructive detected by dual-band board radiometer with multi-angle and du- al-polarization mode. Based on the field data, Levernberg-Marquardt Algorithm was selected to calculate the imagi- nary part of soil permittivityand Dobson model as the real part of soil permittivity. Then, the dual-band different method was used to study the relationship of soil permittivity and salinity,water content. The difference of the real part of soil permittivity between two frequency （band） is well linear relationship with soil water content,while has the difference of the imaginary part with salinity. This result is significant on the inversion of soil salinity character istics, and laid a theoretical foundation for soil salinity quantitative inversion from microwave remote sensing image.