基于TM影像的福州市地表植被变化分析

利用多时相TM影像，通过变化检测和假彩色合成方法分析福州市1989-2000年的植被变化。在影像解译中对所包含的一部分非由植被变化引起的伪信息，依次采用阈值法和掩膜法将伪变化信息剔除。结果表明，用不同时相NDVI影像进行假彩色合成可以直观地反映地表植被的变化。同时通过对伪信息的剔除，提高了图像的精度。福州市在1988-2000年植被覆盖率总体上有明显提高。但部分地区由于人为干扰，植被退化较严重。

Analysis on Land Vegetation Cover Changes of Fuzhou City Based on Landsat TM Images

In this thesis,multi-temporal landsat TM image is used for analysis of surface vegetation change between 1988 and 2000 in Fuzhou,through the methods of change detection and Pseudo color synthesis.However,the resultant different images of NDVI contained false change information that was not produced by the vegetation change.Therefore,a series of thresholds had to be determined to distinguish the false change information from the true one and mask out the false information from the different images.The results prove that using different multi-temporal landsat NDVI image to color synthesis can reflect the change of the surface vegetation directly.And as mask out the false information from the images,the precision of images is improved.Overall,the surface vegetation of Fuzhou has increased during the study years,at the same time,some area’s surface vegetation became degenerated owing to human activity.