Spatio-temporal analysis of sprawl in coastal area of Caspian Sea

With the increasing population in the coastal strip of Caspian Sea, the region with the relative density of over 126 inhabitants per square kilometer, has become one of the densest regions of Iran. In addition, over time, the distribution of population in the coastal zone of the Caspian Sea has been more diffuse; As urban primacy index was significantly reduced at 55 years and the results of elliptical space-based standard deviation confirms the concentration of population in the wider zone compared to 1335. Following demographic trends and the increasing load of population in coastal areas of the Caspian Sea has occurred obvious changes in land cover and land use. Most of the changes belong to the land of cities and villages that has increased with annual growth rates of 2/3% from 1158 hectares in 1364 to more than 3162 hectares in 1394. An increase of about 2 thousand hectares of built up land have occurred mainly by converting vegetation, including agricultural land, forests and pasture to urban lands. The results of the analysis of growth patterns of urban land using sprawl index showed that the growth pattern of urban land in the study area has been urban sprawl or dispersed growth. In this situation, sprawl index, or the ratio between the growth rate of urban land to the population growth rate in the period 1364 to 1394 in the coastal strip of the Caspian Sea is 4/7, that Indicating the existence and dominance the sprawl phenomenon in the study area.