Trend Analysis of Land Cover Changes in Arak City Between 1973 -2011

In recent decades, problems of urban growth and land cover changes has been one of the most important issues on a global and national scale that different technologys were used for the recognition of the nature, dimension and functions of the aforesaid causes and process , among these the remote sensing technology due to its ability to produce high spatial and spectral resolution satellite images is known to be an effective tool for the detection and evaluation of changes. The present study is descriptive – analytical approach which uses Landsat ETM , TM, MSS images acquired in 1973, 1985, 2000 and 2011 in order to analyze the trend of land cover and land use changes. To obtain the magnitude of changes, band subtraction method and fuzzy logic were used. Satellite images were classified using Maximum Likelihood Classifier (MLC) in ARCGIS10.1 software. Results show that as a consequence of increasing population and expanding of urban areas, fuzzy magnitude of changes were equal to 0.84843, 0.92983 and 0.92795 for the periods of 1973-1985, 2000-1985, and 2000-2011 respectively. The urban area have increased 7/6, 15/2, and 11/9 square kilometers during these three periods. And during 38 years, urban area has reached from 14.9 to 49.8 square kilometers which shows an average annual growth rate of 0.918 km2 and correlation between population growth and urban expansion is 0.976.