Response of vegetation coverage on climate change in arid mountain of Northwest China

Arid and semi-arid areas are very easily influenced by global warming because of the simple structure of landscape. The change of climate conditions affected the land vegetation coverage and its distribution in arid areas. As an indicator of vegetation growth and its spatial distribution, NDVI has a close relationship with climate conditions. Based on the remote sensing data GIMMS NDVI and software of ArcGIS, it was analyzed that the spatial-temporal correlations of NDVI with the precipitation and temperature in the Qilian Mountain located in the arid Northwest China in this paper from 1982 to 2003. The results showed that: (1) There was significant positive correlation between NDVI and temperature in the areas above the elevation of 2500 m, and significant negative correlation between NDVI and temperature in the areas below the elevation of 2500 m. (2) The value of NDVI was not visibly related with the precipitation in the both elevation areas. It can be concluded from the results that the vegetation coverage in lower elevation areas in Northwest China will be worse with the global warming.