Rezvan ghorbanisalkhord - Faculty member, Department of Surveying,Technical and Vocational University (TVU),Tehran, Iran

In studies of environmental sciences and natural resources, vegetation should be continuously examined both quantitatively and qualitatively as a variable factor affecting biotic conditions, the importance of which is clear to researchers given that pastures cover most of the land areas globally. In this study, detection of vegetation changes was evaluated by the image subtraction method in NDVI and EVI vegetation indices of the growing season in plain rangelands of Golestan province. In this study, the MOD۰۱۳Q۱ product was used for vegetation sensing data of MODIS sensor images located on the deck of Terra satellite during ۲۰۰۰-۲۰۱۲ on the dates of the vegetation growing season in pastures of Golestan province. Results showed that the NDVI and EVI were complementary to each other in the detection of vegetation changes with a correlation value of ۰.۹۸%. Moreover, the EVI was not as accurate as the NDVI, resulting from a high reflectance in the infrared band relative to red band in arid areas.

Pasture, Golestan Province, Image subtraction, EVI, NDVI, MODIS