The response of temporal and spatial change of vegetation index to hydrothermal condition in the ThreeRivers Headwaters Region

Abstract: The response of temporal and spatial change of vegetation index to hydrothermal conditions was discussed by analyzing the relationship between temperature and precipitation data from 18 meteorological stations and NDVI/EVI from MODIS product during the period 2000-2009 in the ThreeRivers Headwaters region. This study indicated that the vegetation index showed a increasing trend from 2000 to 2009 and its mean value of the vegetation index were uneven distributed among the 18 meteorological stations. The vegetation index was positively significant correlation with precipitation in most years but was not significant correlations with temperature in all years. Data from 7 and 5 meteorological stations among the 18 meteorological stations showed that precipitation and temperature had significant correlations with vegetation index. In generally, the distribution of vegetation index and its relationships between these indexes and hydrothermal conditions had significantly temporal and spatial differences. Meanwhile, the vegetation index had a more strong response to precipitation than to temperature, indicating that the precipitation played a leading role in vegetation growth in the ThreeRivers Headwaters region.