Document Type : .
Authors
Geography Department, Larestan Azad University, Larestan, Iran
Abstract
Unplanned urbanization is growing at an alarming rate in developing countries. This growth has created challenges for development planning and urban risk management. The substantial growing urban population leads to a rise in urban dangers. Consequently, when confronted with natural hazards, these often result in recurring calamities. Risk assessment, as one of the basic tools of risk management, analyzes risk and vulnerability. This tool is used to study the possible and existing risk factors of disasters that can occur and provides the basis for planning and implementing measures to reduce the risks and effects of disasters. In this thesis, considering the potential of flooding in the dry river basin of Shiraz, an evaluation and urban risk management (with regard to urban floods in Shiraz) has been investigated. The purpose of this study is to determine the suitable places for the establishment of temporary centers for the flood-affected population in Shiraz city. It is a descriptive-analytical research method by using which the required criteria and indicators were selected and according to the analysis results by crisis management experts, they were measured as layers in the Arc GIS software. Then, according to the weight given to each of the layers and using the hierarchical analysis process model, places with more compatibility with suitable and very suitable areas have been selected. The results show that the southern, central, and part of the eastern regions are among the regions with high potential for the construction of suitable areas for emergency and temporary accommodation during the occurrence of geomorphic hazards in the dry river basin of Shiraz. In general, the assessment and management of urban risks can be seen as an important step in the risk management process by which available resources can be used to deal with disasters and risks.
Extended Abstract
Introduction
Natural hazards with their various types, as repeatable and destructive phenomena, have always existed throughout the life of the earth and have always been a serious danger to humans. In recent decades, many Iranian cities have faced different challenges during the occurrence of hazards, including the risk of floods. Therefore, planning to reduce the effects of these hazards has a key role in urban crisis management. One of the important stages of crisis management is "temporary accommodation". The main purpose of this research is to review the study of disaster shelter location models to fill the gap in research on location selection across the analysis of objectives, constraints, types of disasters and solution approaches. In this research, according to the type of goals and hierarchy, we present a brief picture of the types of location models. Then the applications of these models in natural disasters such as floods in Shiraz city are discussed. In addition, the approaches used to solve the models are analyzed and compared. This research provides three main contributions. First, we develop a method that considers building damage and loss of function as critical tools for estimating time-varying shelter demand in a large urban area. Second, we propose an integrated location allocation model that includes an estimation method for planning emergency shelters for resilience against urban disasters, especially urban flooding. We reduce the cost of setting up emergency shelters by identifying optimal locations. This ensures the sustainable development of urban resilience planning, as disaster mitigation funds are always limited in reality. Third, we develop a new algorithm based on the mutual entropy method, integrated with the local search mechanism, to efficiently solve the unified location allocation model.
Methodology
Different layers of information have been used to prepare the location map of suitable areas for emergency and temporary accommodation during the occurrence of geomorphic hazards in the dry river basin of Shiraz. By combining these data and using geographic information system (GIS) technology, a location map of suitable areas for emergency and temporary accommodation is prepared during the occurrence of geomorphic hazards in the Dry Shiraz river basin. In this research, we first identify the risk areas. We identify and zone the areas that have geomorphological hazards such as floods using the models available in each field. In order to choose suitable places for temporary accommodation, first of all, the necessary criteria for this location are prepared. After the preparation of these criteria, in the positioning stage, according to the opinion of experts involved in reconstruction management, scoring frameworks are determined based on these criteria. Due to the spatial characteristics of most of the information, preliminary studies are done in the GIS environment according to the possibilities of this software in analyzing and interpreting spatial information.
Results and discussion
After the preparation of different layers based on different criteria of the region, the initial positioning is done using the commands available in ArcGIS software. In order to show the importance of each of the criteria in locating suitable areas for emergency and temporary accommodation during the occurrence of geomorphic hazards in the dry river basin of Shiraz, it is necessary to multiply the weight of each of the criteria in the corresponding layer in the Arc Map software and make weighted maps. related to each of the criteria should be drawn in the software environment. The output of these layers is a range between 0 and the weight obtained in the Expert Choice software. The maps are prepared in such a way that they have the ability to enter the main model. After choosing the appropriate method and model of integration, the maps are entered into the model and the final map is prepared from the combination of information layers using classification classes for the entire study area. The final prioritization of the proposed spaces by including a range of unsuitable to suitable places have been categorized into five classes: very suitable, suitable, medium, unsuitable and very unsuitable. Based on this, the areas that had the most compatibility with suitable and very suitable areas were selected as suitable places; In such a way that the first priorities are in very suitable ranges and the second priorities are in suitable ranges. According to the shape of the region's desirability, the places chosen for settlement after the occurrence of geomorphic hazards are mainly located in very suitable areas. According to the surveys, as shown, a large part of this basin is in the area of very inappropriate desirability.
Conclusion
The integration of the criteria related to the location of suitable areas for emergency and temporary accommodation during the occurrence of geomorphic hazards in the Shiraz dry river basin shows that the north, west, southwest and southeast areas of the dry Shiraz river are among the areas with the lowest value in creating a crisis management base. They are a city in the dry river basin of Shiraz; However, the southern, central and part of the east regions are among the regions with high potential for the construction of suitable areas for emergency and temporary accommodation during the occurrence of geomorphic hazards in the dry river basin of Shiraz
Keywords
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