Detection of landscape change (1954-2008) in Isfahan using gradient methods in GIS environment

Abstract

Urban landscape is rapidly changing due to urbanization and population growth. This phenomenon has a number of social- economical and environmental consequences. Due to the rapid growth of urbanization and enormous changes of the applications, Isfahan`s city landscape has been changed. This study aimed to detect spatial gradients of the city in the period of 1954 to 2008. Therefore, the land used map of years of 1334 and 1386 was provided in six categories of man-made, agriculture, green spaces, arid, road and river. Gradient analysis was used to compare the changes. Transects 17×3 in north-south direction were used to analyze the gradient. The results of the comparison of transect in a certain time period showed that the gradient of the changes of applications and Metrics in 1954had more asymmetry than those of 2008. Thus, transects` margins were occupied with the combination of agriculture and arid lands ant its center was occupied with manmade lands. Comparison of metric values along transects showed the city’s downtown landscape pattern has not changed much and variations of the margins are much bigger. The overall mean and standard deviation of the patch size of the BLOB size is greater than the margin transects. In general, the mean and standard deviation of the patch size is higher in the margins of transects and on the contrary, the patch density and margin density is higher in downtown.