Changes in vegetation dynamics in the interior and exterior of anthropogenic activities in the Central Zagros

Today, one of the most important issues in economic, social planning and future decisions in an area is the awareness of vegetation rates and its spatio-temporal variations. The purpose of this research is to investigate vegetation changes in Central Zagros using MODIS Terra satellite data with spatial resolution of 250 m (2001 - 2018) and NDVI index. At the same time, DEM and DSM models and bilinear interpolation method were used to resampling. These data were processed to analyze vegetation changes in the interior and exterior of anthropogenic activities in the Central Zagros. The results showed that the NDVI index has increased in these altitudes and within mountain passes and valleys and in areas and lowlands adjacent to the slopes to the southwest, especially the Khuzestan plain. At the same time, the temporal trend of vegetation changes in the Central Zagros shows the increase of the NDVI index in this period. In the Central Zagros in January, the vegetation index at low altitudes, especially towards the Khuzestan plain, has a significant increase compared to higher altitudes; Therefore, nomads migrate to winter settlements. Meanwhile, in May, it is possible to establish nomads at higher altitudes and use high rangelands, resulting in nomadic summer migration. Spatial changes of vegetation within the interior and exterior of human activities showed that the increase of the average positive part of the vegetation index within the 5 km around of the cities is due to the expansion of gardens, agriculture and green area in this region. The relatively noticeable trend outside of that is also caused by temperature changes and the general trend of increasing vegetation index in central Zagros. The increase in the vegetation index in the 1km around of the communication roads and villages , as well as the areas outside it, can be related to the increase in temperature due to global warming and the reduction of winter snow-covers and due to the expansion of fields and gardens around the villages, roads and green area created in the around of roads and villages.