Abstract: The Wenchuan Earthquake (Richter scale 8) on May 12, 2008 caused widespread ecosystem damages in the Minjiang River Basin. It is important to evaluate the natural vegetation recovery process and provide basic information on ecological aspects of the recovering environment after the earthquake. To circumvent weather limits of remote sensing and to meet the need for regional observation analyses, three Landsat TM images pre- and post-earthquake in the Minjiang arid valley were used for analysis. The post-earthquake vegetation cover values were compared to the pre-earthquake value to determine the extent to which the vegetation was damaged in relation to the pre-earthquake pattern, and the rate of recovery was evaluated. Spatial characteristics of vegetation loss and natural recovery pattern were analyzed in relation to elevation, slope and aspect. The results showed that (1) the landslides caused by the earthquake was 5 413.95 hm², accounted for 34.74% of the total area; (2) there is a good correlation between recovery rate and both slope and elevation; (3) after three years, the average vegetation recovery rate reached 66.71%. Our study also showed that there was a high congruency between recovery rate and both slope and elevation, and the recovery patterns were complicated.

Key words: NDVI, 5.12 earthquake, vegetation dynamic, Minjiang River