COMPARISON OF THREE MODIS AND LANDSAT 8 OLI VEGETATION INDICES IN DIFFERENT ECOLOGICAL ZONES OF IRAN

Regional vegetation cover not only plays an important role in monitoring vegetation situation and change on the land surface, but also is an important indicator in modelling environmental quality, changes and conservation. Using MODIS data with medium resolution can be useful in order to analyze vegetation coverage at national scale. However, accuracy and reliability of MODIS data should be evaluated. In this study, we tried to compare three MODIS vegetation indices (NDVI, SAVI, and EVI) with Landsat 8 OLI VIs in 5 different ecological zones of Iran. Eight regions were selected in these 5 zones and 386 corresponding VI images in 3 seasons in 2014 and 2015 were prepared using MODIS and Landsat 8 data. The kappa coefficient was used to assess the accuracy of MODIS Vegetation indices. The results show that 84.09 percent of the selected areas have kappa coefficient more than 0.9, which indicates high reliability of MODIS data especially in studies of vegetation classification.