Regional Distribution and Seasonal Variation of MODIS/NDVI over Shaanxi Area

The growing status of different vegetation types in their developing periods and their spatial difference can be understood in detail by analyzing the spatial and temporal variation of MODIS/NDVI.Research on Monthly NDVI data set over Shaanxi,which has been composed by the method MVC using 2004 MODIS data,shows: ①the yearly average of MODIS/NDVI over Shannxi is 0.39,changing between-0.54~0.85.The monthly distribution of NDVI appears a single peak in winter,but double peaks in the other seasons.②The difference of NDVI distribution between the north and the south of Shaanxi is smaller in winter,but larger in the other seasons.The distribution of NDVI in summer and autumn reflects the regional characters of the sand-blown region along the Great Wall in the north of northern Shaanxi,the hill and ravine region on loess plateau,the forest region in Ziwuling and Huanglong mountains,the farmland region in Guanzhong,the forest and farmland region in Qinba mountain.③There are remarkable differentiation of seasonal NDVI among different types of vegetation.