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本文以MODIS数据为基础,构建了基于归一化植被指数(NDVI)的植被覆盖估算像元二分模型,分别计算汶川地震灾区2008～2015年共8个时相的植被覆盖度,以此为基础定量分析了汶川地震对植被的破坏程度,地震后植被逐年恢复状况.结果表明:地震灾区平均植被覆盖度在震后显著降低,其降低程度与地震烈度呈正相关,截至2015年,灾区平均植被覆盖度恢复至地震前水平.不同烈度区植被覆盖变化速率和构成具有差异性,总体表现为烈度9°区恢复速度最快,7°区恢复速度最慢,不同等级植被覆盖度的空间格局发生了显著变化.研究结果对发展遥感植被覆盖监测理论,汶川地震灾区生态环境恢复、灾害评价与水土保持等具有重要理论和现实意义.“,”Based on MODIS data and the normalized difference vegetation index (NDVI),dimidiate pixel model of vegetation coverage estimation was built,then the vegetation coverage was calculated in the disaster area of Wenchuan earthquake from 2008 to 2015,and the vegetation coverage of eight phase was obtained.After the Wenchuan earthquake the damage degree of vegetation and the year by year recovery of vegetation was analyzed quantitatively.The results show:Average vegetation coverage in the earthquake-stricken area decreased significantly after the quake,the decreased level was positively related with earthquake intensity.By 2015,the average vegetation coverage has returned to the same level as before the earthquake.The vegetation coverage rate and composition in different intensity area are not the same,which the recovery in the intensity of nine degree area is fastest,and the recovery in the intensity of seven degree area is slowest.The spatial pattern of different levels of vegetation coverage has significant changed.The results has important theoretical and practical significance on the development of remote sensing vegetation monitoring theory,the ecological environment recovery of Wenchuan earthquake disaster area,disaster evaluation and soil and water conservation.