Assessment of urban land expansion using remote sensing and GIS: A case of Shiraz city, Iran

Abstract

Urbanization and urban development is undoubtedly one of the most crucial aspects of modern civilization, causing various changes in the environment. Shiraz an area identified for rapid urban growth is less explored in the matter of study. In this context, this study presents a combined approach of remote sensing and GIS techniques for monitoring land use changes of Shiraz city in Fars Province, Iran. Firstly, various satellite images, including MSS 1982, TM 1996, ETM 2006, and OLI 2018 based on five classes, namely agriculture, urban areas, bare land, tree cover and street were classified. For classify the remote-sensing data maximum likelihood algorithm was used. Then, digital topographic maps 1:50000 of Geographic Organization of the Armed Forces and Mapping Organization were used as ancillary data for interpreting the images, also for geometric correction of the images. In the final phase of the study, the extent and status of changes in each application were determined, and the trends of changes were investigated. The results indicate a significant change in land use in regard to expansion of an urban area from 17.30% (1982) to 46.40% (2006) and 47.8% (2018) by encroaching into agricultural and bare lands. Over this period, urban area has expanded by 624 Ha per year on the average while this increase has been 238 Ha per year for the period 1996-2006. Moreover, during the first period, 198 Ha of agricultural land has been degraded annually while this rate was 14 and 19 Ha for the second and third periods, respectively, showing, increasing and declining trends in cover and application of the land over the three periods within the study area. The results of this research can be utilized as essential data to strengthen the effectiveness of the later urban planning of Shiraz City.