Ding M,Zhang Y,Liu L,et al.The relationship between NDVI and precipitation on the Tibetan Plateau[J].Journal of Geographical Sciences,2007,17(3):259-268.
[4]
Zavaleta E S,Shaw M R,Chiariello N R,et al.Grassland responses to three years of elevated temperature,CO2,precipitation,and N deposition[J]. Ecological Monographs,2003,73(4):585-604.
[5]
Piao S,Mohammat A,Fang J,et al.NDVI-based increase in growth of temperate grasslands and its responses to climate changes in China[J].Global Environmental Change,2006,16(4): 340-348.
Wang Z,Song K,Zhang B,et al.Shrinkage and fragmentation of grasslands in the West Songnen Plain,China[J].Agriculture,Ecosystems & Environment,2009,129(1):315-324.
Piao S L,Fang J Y,Zhou L M,et al.Interannual variations of monthly and seasonal normalized difference vegetation index (NDVI) in China from 1982 to 1999[J]. Journal of Geophysical Research, 2003,108(D14):4401.