基于遥感和GIS的东亚土地覆盖年际变化研究

土地覆盖的年际变化是以土地覆盖的宏观分布模式为基准，在外界驱动因子的作用下发生的年与年之间的变化，因此，为揭示东亚地区土地覆盖的年际变化特征，首先选取东亚地区时相一致的不同空间分辨率（1km和8km)的NDVI影像进行了非监督分类，并总结了东亚土地覆盖的宏观分布模式，然后以时间序列的8kmAVHRRNDVI数字影像为基础，应用跨平百分率分析方法生成每年5-9月距平百分率分级影像，并以该影像为基础分析总结了东亚土地覆盖的年际变化特征，结果显示，该方法及其揭示的现象比较客观地反映了东亚土地覆盖年际变化特征。

Study on Interannual Variance of East Asian Land Cover Based on the Remote Sensing and GIS

Macroscopical distribution pattern of land cover is a foundation for the land cover's interannual change that is being occurred by the outside driving force. In this study, unsupervised classification method have been used based on the different NDVI images which have different spatial resolution and same temporal, and the macroscopical distribution pattern of East Asian land cover was summed up. Furthermore, annual 5~9 months anomaly percentage grading images have been made using Anomaly Percentage Analysis methods based on the NOAA/AVHRR Pathfinder database, which are 8km spatial resolutions and 10 days temporal resolutions, and generalized the characteristic of interannual changes of east Asian land cover. Which are can be seen as follows: (1)Land cover dynamic of summer(5~9 month) in east Asia apparently differentiated three regions such as the northwest inland area, eastern monsoon area and northern part of east Asia. (2)Inside the monsoon area, land cover dynamics have shown to have trends of differentiate of southeast to northwest. As regards the whole, the interannual changes of land cover of Northeast China Plain, North China Plain, southwest China and Huaihe basin are relatively heavy. (3)In the edge of monsoon area, there exist an obvious dynamic zone which is expanded from northeast to southwest. This is consistent with ecological environment fragile area of northern part of China. (4)In the northern part of east Asia, the land cover's interannual dynamic have feature of zonal distribution. In the same zone, there exist difference of east to west, but the interannual changes are very simple. (5)From the interannual changes of land cover, we have seen that the land cover have trends of increase except northwest inland arid area, especially in the northern part of east Asia and midwest Qinghai-Tibet.