基于ETM+影像的扎龙湿地遥感分类研究

Method of Wetland Classification Based on Landsat7 ETM + Image

通过对扎龙湿地Landsat7 ETM+影像进行计算机自动分类的实验研究,探讨了提高湿地遥感分类精度的方法与途径。实验所采用的首先对遥感影像进行非监督分类,再利用非监督分类生成的分类模板加以修改补充后进行监督分类的方法,经过误差矩阵的精度评价,可以获得研究区湿地遥感分类较高的分类精度。利用上述分类方法对3种ETM+不同波段组合的影像进行具体的遥感分类比较研究发现,选择ETM+7、5、3影像进行分类有助于提高扎龙湿地遥感分类的精度。为了提高湿地遥感分类的精度,还必须运用人机互译判读方法。

<abstract>is paper is primarily conducted to approach the method which could improve classification accuracy of wetland in Zhalong, China,using Landsat7 ETM+ Image. As a result, it was found that the better classification method was produced by integrating unsupervised classification and supervised classification procedures before image interpretation. This method was illustrated with three examples of wetland classification carried on ETM+ band 4,3,2 image, ETM+ band 3,4,5 image and ETM+ band 7,5,3 image. It is beneficial to enhance the classification accuracy in Zhalong wetland using ETM+ band 7,5,3 image. Water, which is the important factor working on distributing of wetlands, is mostly sensitive to the wave band 5 and band 7, furthermore, wave band 5 contains abundant spectral information. The contrast of three examples illustrates that the best wave band combination in Landsat7 ETM+ image to interpret the wetland classification is band 7,5,3. Last but not the least, interactive interpretation approach has to be applied in the study for the sake of higher classification accuracy of wetland. From the practical point of view, the difference of interpreters, the knowledge of related bio - geography, the proficiency of mastering softwares, the familiarity with the research area, has a remarkable influence on the classification accuracy.