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探讨了使用HSI影像研究大面积土壤盐渍化状况的可行性。方法是:使用HSI影像作为数据源,将大气校正以后的地表反射率进行多种数学变换,然后与采样土壤含盐量的化验数据进行回归分析,建立土壤含盐量的反演模型,最后将采样点土壤含盐量的反演值与实测值进行比较,评价模型的预测能力。结果表明:HSI影像经过大气校正后可以消除水汽对反射率的影响,有利于土壤含盐量的反演;影像中的反射率经过一阶微分(R’)、倒数的一阶微分(1/R)’等数学变换后可以显著提高与土壤含盐量的相关系数,判定系数R2达到0.547和0.556;利用回归分析方法所建立的反演模型能够较好的反演松辽平原盐碱土的含盐量。
The feasibility of using HSI images to study the salinization of large areas of soils was discussed. The method is that: using HSI image as data source, carrying out multiple mathematical transformations of the surface reflectance after atmospheric correction, and then performing regression analysis with the experimental soil salinity data, establishing an inversion model of soil salt content; finally, The inversion values of soil salinity at sampling points are compared with the measured values to evaluate the predictive ability of the model. The results show that the HSI image can eliminate the influence of water vapor on the reflectance after atmospheric correction, which is in favor of the inversion of soil salinity. The reflectance in the image undergoes the first derivative (R ’), the first derivative (1 / R) and other mathematical transformation can significantly improve the soil salinity correlation coefficient, the determination coefficient R2 reached 0.547 and 0.556; using regression analysis established inversion model can better reverse the Songliao Plain saline-alkali soil Salt content.