Land use change and land cover are considered as one of the important and effective factors on global environmental change, so understanding and predicting the causes, processes and consequences of land use change has become a major challenge on the planet. Today, remote sensing technology and GIS are used effectively to identify and quantify land use change and its effects on the environment. The physical development of cities and the expansion of its dimensions is one of the important factors in urban land change that has many environmental, economic and social consequences. In the past few decades, the city of Tehran has faced numerous urban growth and development and surrounding towns, which has caused extensive changes in the urban lands of Tehran and surrounding areas. In this study, the trend of land use changes in Tehran in the past few decades has been studied. In the present study, using Landsat 8 satellite images, the change and transformation of lands in Tehran from 2013 to 2020 was monitored. Images were pre-processed and classified according to the LCZ model in 17 classes. Then, they were classified in SEGA GIS software and analyzed by image difference and post-classification methods. The results of image processing and classification show that urban lands are constantly growing and barren lands are increasing on a very small and slow scale. Also, land with dense vegetation has decreased from 2013 to 2020, which in itself can cause serious damage to urban planning for city managers. تفاصيل المقالة

Several methods have been developed to represent flood-related hazards using ground-based measurements. Satellite remote sensing data have been used for flood assessment due to their spatial resolution and capacity to provide information for areas with poor access or lack of ground measurements. Identifying flood prone areas is one of the basic strategies in planning to reduce the destructive effects of floods. Flood is considered as one of the events that causes damage to human societies. Therefore, the importance of estimating the damages caused by flood and determining its extent in planning to reduce these damages and determining high risk points is very important. For this purpose, the OLI sensor images of Landest 8 satellite, before and after the flood of April 2018 in Khuzestan, Hoyze region, were used. Then NDWI water index was used for identification and SVM (Support Vector Machine) method was used for classification and it was found that before the flood there were 36999.99 hectares of water areas in the region and after the flood this amount reached 274279.95 hectares. The results show that the south and south-west parts are in a very severe situation and the central and south-eastern parts are in a severe flood risk situation, which are among the most prone to flood areas in the province. Also, the monitoring of flood maps in Khuzestan province shows that there is a perfect match between the flood zone map and the recent flood. تفاصيل المقالة

One of the processes that can examine the changes of the city for a period of several years and as a result predict the directions of urban growth and development in order to implement appropriate planning is urban development modeling. Therefore, urban designers and planners need spatial and temporal information related to urban growth patterns obtained through modeling. To discover and evaluate changes and urban development, multi-time remote sensing data can play an essential role due to the cheapness and speed of obtaining data from it, and geographic information system due to its analytical capabilities. It is necessary to pay attention to the fact that the size of the studied area as well as the required spatial resolution is important in choosing the type of satellite. The purpose of this research is to investigate the urban development situation in the 22nd district of Tehran, which has not been researched in this field using satellite data. In this research, we have analyzed the data of Landsat satellite in 2003 and Landsat 2018 in a period of 16 years. The studied area is the 22nd district of Tehran Municipality and due to the expansion of urbanization in this area, the relevant results showed that the development of urbanization in the 22nd district is increasing significantly and this trend is increasing towards the west of Tehran. In these 16 years, there has been the biggest change in the land use of barren land, which has become an urban area. تفاصيل المقالة