Investigating the Relationship between Vegetation Indices and the Occurrence of Wildfire in the Vegetation Areas of Iran

The risk of wildfire in Iran has increasingly become a serious risk throughout the year and is no longer limited to a few months of the year. Accordingly, forest monitoring for identifying areas prone to fires is an effective step for the development of early warning systems. This research was conducted to see the relationship between the vegetation indices with the occurrence of fire in the vegetation areas of Iran. The MODIS sensor data of the Terra satellite, including the active fire product (MOD14A2) and vegetation indices NDVI and EVI (MOD13A3) were used from 2001 to 2020. The results showed that the maximum occurrence of wildfire in the vegetation areas of Iran occurs from the end of spring to the beginning of autumn. The increasing trend of wildfire occurrence in the warm period of the year is related to the increase in temperature, decrease in humidity, and early melting of snow in the spring season and the autumn season, simultaneously with the fall of vegetation and the late start of autumn precipitation. The maximum average height of wildfire occurrences in the Arsbaran vegetation area is 1791 meters in October and the maximum height of wildfire occurrences in the Irani-Turani area is 1565 meters in August. Spatial distribution of NDVI and EVI indices showed that the density of vegetation is effective in the intensity and spread of wildfire and provides the conditions for the spread of wildfire in such a way that barren areas with low vegetation cover the center, east, and southeast of Iran. Almost no wildfire occurred and the maximum number of active fires was observed in the north, west, and northwest of Iran.