Estimating relationships between NDVI and climate change in Guizhou Province, Southwest China

The objective of this study was to examine the vegetation response to the climatic variation in Guizhou province, Southwest China. The relationship between vegetation and climate change was investigated with Normalized Difference Vegetation Index (NDVI) (1982-1999) images derived from the Advanced Very High Resolution Radiometer (AVHRR), and climate data acquired from 19 meteorological stations in Guizhou province. Five climate variables during the growing season (March to October): precipitation, evaporation, mean temperature, solar irradiation and water surplus (the arithmetic difference between precipitation and evaporation) at 10-day time scale were regressed on NDVI derived from 8 km×8 km pixels where the weather stations located. The main results were: (a) temperature and evaporation are the most significant climatic variables controlling vegetation condition; (b) evaporation are positive to vegetation growth at the 10-day time scale. The model also indicated that 11.8% variation in NDVI is accounted for by climate. Other factors contributing to NDVI variation include environmental factors (soil, groundwater and terrain) and sensor variation. The present study will be helpful in estimations of response of the regional terrestrial biosphere to global environmental change.