Comparison of NDVI and EVI based on EOS/MODIS data

As the continuation and development of NOAA/AVHRR NDVI,the normalized difference vegetation index(NDVI) and enhanced vegetation index(EVI) of MODIS have been comprehensively used in many fields.In order to investigate the difference between NDVI and EVI derived from MODIS,comparative study of these two vegetation indices was conducted by statistics and geo-statistic methods(semi-variance function).By the comparison of the two kinds of vegetation index distribution maps in different period,it is demonstrated that EVI improve the sensitivity for well-vegetated areas where NDVI is saturated when plants grow well,which will be helpful in monitoring plants growth status.At same resolution,i.e.250m,500m and 1000m,by means of the geo-statistics,the results show that range,variance and variation coefficient of EVI is higher than that of NDVI,the value of NDVI is even,and its spatial relativity is higher than that of EVI,which all show that EVI is more sensitive to the spatial heterogeneity of plants in research area.