| The soil salinization is the land degeneration which is caused by the unreasonable human activity and the frail ecological environment in the arid and semi-arid area, which is nowadays as an important environmental and social economy question as the desert in the world. According to the statistics,there are 952 million km2 salinization land in the whole world,and China is one of countries which are affected seriously, where the question of the soil salinization is still extremely prominent. The soil salinization is comprehensively concerned by more and more people in the whole world because it brings the destructive effect to the social economy, environment and the agriculture ecosystem. It is very important to father saline soils, prevent further pervasion and degeneration, continue to develop the agriculture, and carry on the reasonable plan using remote sensing high-tech technology, which is characteristic by its macroscopic, comprehensive, dynamic and fast quality, to study the quality, the scope, the area, the geographic distribution, the dynamic change and the degree of saline soils.This article uses the radar images as the most important data, which is also the application of radar images for the first time in arid area of Xinjiang. This article also comprehensively uses the superiority of other remote sensing and the spatial data, enhances the extraction precision of saline soils information, thus comprehensively explores and evaluate quantitatively the soil salinization in the arid and semi-arid area, develops applied research on the extraction of saline soils information using microwave remote sensing, provides the highly effective decision system ,which serves for the sustainable development, to all levels of governments and the policy establishing department, and makes the contribution for the western big development.1. Analyze the elimination of SAR images spot noise with different filter method and different window size. In order to eliminate the SAR image spot noise, using the Lee filter, the enhanced Lee filter, the Frost filter, the enhanced Frost filter, the Gamma filter, the Kuan filter, the Local Sigma filter, the Bit Errors filter to process the radar image, this article has analyzed the S.D change under different window sizes, then taken the indexes of FI and ESI under different window sizes to analyze the change of the typical things of severe saline soil, middle and light saline soil, farmland, water body and the clay. The result indicated that the effect of the enhanced Frost filter and the enhanced Lee filter to remove the spot noise was satisfied.2. Analyze the application of decision tree classifier on the extraction of saline soils based on multiple source data in arid area. Firstly salinization causes were discussed. The results shows that arid desert climate is a prerequisite to the formation of salinization, parent rock containing salt is the material basis for the formation of salinization, surface water and groundwater supplies are the impetus to the formation of salinization, human factors is a key factor to the formation of secondary salinity in irrigation areas. Through contrast on whether the radar waveband was used on decision tree classifier the result indicated that after the radar waveband was joined to carry on principal component transformation, the fifth principal components can separate the water body information and the severe saline soil information, and can extract the severe saline soil information effectively. Through the decision tree classifier model established, the model which was joined by the radar waveband has less pitch points, reduces the operation process, makes the entire extraction flow of saline soils information more concise, and the selection of characteristic waveband was also more convenient and the precision of extraction also has remarkable increase.3. Analyze the application of multiple source information fusion on the extraction of saline soils based on in arid area. Firstly the paper carries on the outline to the commonly used remote sensing image fusion method, then uses the fusion method of HIS, Brovey and PCA to fuse the radar image and optics image to enhance the precision of extraction of saline soils. The result indicated that the picture based on the principal component fusion had enhanced the resolving power greatly, and enhanced the discriminations between the saline soils and other things. The precision of extraction result is higher than the result based on simply optics images, and it can be explained that the radar image has the superiority in information extraction of saline soils.4. Analyze the response of the radar image to the ion of saline soils. First carries on measures on eight large ions of saline soils on the typical region, according to the measuring point coordinates of field, calculates the value of each point in the remote sensing image with the values of eight large ions corresponding, then uses the gray associate analytic method to carry on the relevant arrangement of eight large ions and the value of the remote sensing images. The result indicated that, Radar images in March responded to PH value intensely, was unstable to the salt content, was middle to the conductivity and the hardness degree. Speaking of the positive ion, the response is most remarkable to the Ca2+; Speaking of the negative ion, the HCO3- response is most remarkable. Radar images in October responded to PH value and conductivity intensely, was unstable to the salt content, was middle to the hardness degree. Speaking of the positive ion, there is no evident rule; Speaking of the negative ion, the Cl- response is most remarkable and there is no evident rule in SO42- and HCO3-. Radar images in March or October responded to PH value stably in 0-10cm or 10-50cm, was unstable to the ion of HCO3-. Speaking of the positive ion, there is no evident rule; Speaking of the negative ion, there is great change in HCO3- and SO42- and there is no great change in Cl-.In brief, the paper uses different research technique, and discusses the application of the radar image on the extraction of saline soil information in the arid area. This research applies the radar image to the extraction of saline soil information for the first time in Xinjiang, and comprehensively uses the superiority of other remote sensing and the spatial data to evaluate the saline soils quantitatively.Using the technology of decision tree classifier, multiple source information fusion, and gray associate to analyze the potential of radar images on the extraction of saline soils in the arid areas, its method and the conclusion has a higher theory and practice value to the examination of saline soils information in the arid area of Xinjiang.
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