With Weiku oasis in Xinjiang as the study area, the authors used two polarization methods, i.e., Freeman-Durden and H/α, to decompose and treat 4-polarization data of the Radarsat-2, got the corresponding characteristic parameters, extracted the salinization information of the study area combined with the SVM-Wishart semi-supervised classification method, and finally checked and analyzed the result of the classification with the visual interpretation and the field investigation. Some conclusions have been reached: ① When the impact categories are identified and the parameter feature space is built to get the characteristic parameters, different polarization decompositions yield different resolutions of parameter information, and the distributions of parameters characteristic space are different; after decomposing with H/α, the characteristic space constituted by characteristic parameters are different; ② The effect of using semi-supervised classification method to classify the endings of the Freeman Durden and H/α,Freeman Durden classification is superior to that of H/a; ③SVM-Wishart semi-supervised classification is superior to traditional SVM classification and hence it can be well used to extract the salinization information. SVM-Wishart semi-supervised classification can fully excavate the characteristic parameters after the coherent decomposition of polarization and can improve the classification accuracy, and it has certain advantages in the extraction of salinization information.
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2019, Vol. 31 
), 魏雯瑜1,2
