基于MODIS NDVI的吉林省植被覆盖度动态遥感监测

植被覆盖度是植物群落覆盖地表状况的一个综合量化指标,植被覆盖及其变化是区域环境变化的重要指示,对于区域水文及生态状况、全球变化的区域响应等都具有重要意义。以MODIS NDVI为数据源,采用像元二分模型,提取2000~2007年吉林省植被覆盖度,获取不同时期的植被覆盖度图,并进一步分析了植被覆盖度变化的原因。结果表明：吉林省植被覆盖度由东部到西部逐渐降低,其中白山地区植被覆盖情况最好。过去8 a间,吉林省植被覆盖度总体呈上升趋势,2007年植被覆盖度达到最高,为83.04%。在此期间,中部地区和西部地区植被覆盖增加了 797.52 km²,占总面积变化的74.79%。生态恢复工程、降水和气温等是影响植被覆盖度变化的主要因素。

Dynamic Monitoring of Vegetation Fraction Change in Jilin Province Based on MODIS NDVI

As a comprehensive quantitative indicator of surface conditions covered by plant communities,vegetation fraction and its changes become an important instruction of regional environmental changes,which has great significance for the regional hydrology and ecological conditions and even the regional response to global changes.In this paper,MODIS NDVI was selected as the data source to finish the extraction of vegetation fraction in Jilin from 2000 to 2007 and vegetation fraction maps from different periods using the two sub-pixel model.It also makes further analysis on the reason for the changes of vegetation fraction.It shows from the results that the vegetation fraction,which is best in Baishan,decreased gradually from east to west in Jilin.Over the past eight years,the overall trend of vegetation coverage in Jilin was on the rise,and the highest had reached 83.04% in 2007.During the period,the vegetation coverage in both central and western regions had increased 9 797.52 km²,accounting for 74.79% of the total area changes.The main factors affecting the changes of vegetation cover are those,the ecological restoration engineering,the precipitation,the temperature and so on.