摘要：The accurate monitoring of vegetation pheno-logical information in meadow steppe has great significance for understanding regional and global climate change and the grassland ecosystem carbon cycle.We used the MODIS normalized different vegetation index (NDVI),enhanced vegetation index (EVI),GOSIF solar-induced chlorophyll fluorescence (SIF) and carbon flux gross primary productivity (GPP) data to estimate the phenology of Changling meadow steppe in China from 2007 to 2010 and compared the differences in the NDVI,EVI and SIF in estimating the phenology of meadow steppe.The results showed that the R2 of SIF and GPP was 0.82,which indicated that SIF could be used to monitor the growth of meadow steppe.Further analysis of the phenological information showed that the phenological information monitored by the NDVI,EVI and SIF lagged behind that of the carbon flux GPP.In addition,SIF was better than the NDVI and EVI in monitoring meadow steppe end date ofthe growing season (EOS) (R2 = 0.72).Meanwhile,the NDVI,EVI,SIF and GPP of meadow steppe had the same sensitivities to environmental factors.Therefore,SIF has the potential to monitor the phenological information of meadow steppe and can better reflect the date of the EOS in meadow steppe,providing an important basis for the in-depth study of the terrestrial ecosystem carbon cycle and its response to climate change.
