Periodicity analysis of NDVI time series and its relationship with climatic factors in the Heihe River Basin in China

Based on the protensive GIMMS NDVI data set and meteorological data during 1982-2009 in the Heihe River Basin, a novel multiple time-scale analysis method, Empirical Mode Decomposition (EMD), is used to diagnose the periodicities of NDVI, air temperature and precipitation data. At the same time, the relationship among these three elements is performed. The results indicate that SINDVI, temperature and precipitation have the similar 3 and 10 years quasiperiodic in the upper reaches of the Heihe River Basin. SINDVI and temperature have the similar 3 and 10 years quasi-periodic, SINDVI and precipitation have the similar 3, 6, 8 and 15 years quasi-periodic in the middle reaches of the Heihe River Basin. In the meantime, in the lower reaches of the Heihe River, SINDVI and temperature have the similar 3 and 10 years quasi-periodic, SINDVI and precipitation have the similar 3 and 6 years quasi-periodic. It is indicated that the temperature and precipitation are both the driving factor affecting the vegetation in the Heihe River Basin. In addition, the EMD method can be effectively used to analyze the relationship between time series data and the meteorological data.