طراحی و پیاده سازی یک مدل gis مبنا برای برنامه ریزی اسکان موقت در مدیریت بحران زلزله شهر بابل

برنامه‌ریزی اسکان موقت زلزله باهدف کاهش آسیب‌ های ثانویه زمین ‌لرزه همواره یکی ازدغدغه‌های اصلی برنامه ‌ریزان و مدیران شهری بوده است. در گذشته برنامه ‌ریزی اسکان موقت صرفاً با توجه به اصولی مانند خالی بودن زمین یا بدون مالک بودن آن صورت می‌گرفته، اما امروزه این کار با استفاده از فناوری‌ های نوین مانند gis و با در نظر گرفتن معیارهای متعدد مکانی و توصیفی انجام می‌شود. با توجه به اینکه تاب آوری شهری از مهمترین شاخه ‌های مدیریت بحران شهری می‌باشد، لذا ارزیابی خطرپذیری و برنامه ‌ریزی برای کاهش آن ازجمله مکانیابی اسکان موقت (به عنوان یکی از اصول تاب آوری شهری) بسیار ضروری است. با بررسی‌های صورت گرفته شهر بابل وضعیت مناسبی از نظر اسکان موقت زلزله زدگان ندارد که آن هم، به دلیل عدم توجه به لحاظ  نمودن این مراکز مهم در برنامه ‌ریزی شهری می‌باشد. در تحقیق حاضر، نظرات کارشناسان خبره با تخصص‌های مهندسی سازه، زلزله، شهرسازی، مدیریت بحران، پدافندغیرعامل، ترافیک و حمل و نقل مورد استفاده قرار گرفته و معیارهای موثر در مکانیابی مراکز اسکان موقت استخراج و وزن ‌دهی شدند. سپس با استفاده از توابع تحلیلی gis، نقشه‌های معیار تولید و با ترکیب آن‌ها بهترین مناطق برای اسکان موقت (پس از زلزله احتمالی) در شهر بابل مشخص شد. با تحلیل نتایج مشخص شد که تنها 7 درصد از محدوده شهر بابل برای اسکان موقت مناسب است. این مناطق با توجه به سایر استانداردهای اسکان موقت مورد بررسی قرار گرفتند که در نهایت شش محل و در مجموع 107 هکتار (کمتر از 4درصد) برای اسکان موقت مناسب تشخیص داده شد. اگرچه این 107 هکتار در حال حاضر می‌تواند پاسخگوی نیاز شهر بابل با توجه به جمعیت کنونی آن باشد، اما اگر نرخ رشد جمعیت شهر بابل و از طرفی افزایش ساخت و ساز و در نتیجه آن کاهش فضای مناسب برای اسکان موقت در نظر گرفته شود، قطعاً در آینده‌ای نزدیک شهر بابل با کمبود فضای مناسب جهت اختصاص به اسکان موقت زلزله ‌زدگان مواجه خواهد بود.

Designing and implementing a GISbased model for temporary accommodation planning in the management of earthquake crisis in Babol City

Introduction Natural hazards have always been a part of our surrounding environment and human life would be unimaginable without considering these hazards. With the development of social life, and particularly with urbanization and increasing expansion of cities, the dimensions of such incidents have become more complicated. Earthquake is one of the most important natural hazards that takes the lives of many people every year. Although definite prediction of earthquake is not still possible, highrisk areas can be identified by zoning earthquake hazard using new technologies such as GIS, and measures can be taken to deal with the critical situation of identified regions during an earthquake. Planning of temporary accommodation with the aim of crisis management and reduction of secondary damages caused by the earthquake have always been amongmajor concerns of urban planners and managers. In the past, the policy of creating temporary accommodation centers and disaster relief sites lacked a specific program, so that locating a vacant land, with no owner was the most important principle for the creation of these centers in urban areas. It is now proved that these methods lack efficiency. However, recent advances in modern technologies such as GIS have improved planning process. This kind of planning procedure takes effective parameters and criteriainto account, many of which have spatial nature. Urban resiliency is one of the most important branches of urban crisis management, thus risk assessment and risk reduction planning, including site selection for temporary accommodation (as a principle of urban resiliency),are highly essential.   Materials and methods The study area of the present research is Babol, one of the major and central cities of Mazandaran Province. Babol is located in BabolCounty, 14 km from the Caspian Sea and 10 km from the Alborz Mountains. With a total area of approximately 32 km2 and a population of250,217 (at the2016 census), it is the second most populous city in Mazandaran province.The 600 km long Caspian faults and 680 km long Alborz faults are among the effective faults of the study area. In the present study, effective measures for selectionof temporary accommodation siteswere extracted and weighted using expert opinions specialized in structural engineering, earthquake, urban planning, crisis management, passive defense, traffic and transportation. Identified criteria included distance from the river, distance from the fault, land use, distance from installations network, access to the transit network, distance from fire stations, population density, distance from tall buildings, distance from police stations and distance from health centers. Then, using GIS analytic functions, standard maps were produced and combined to identify the best areas for temporary accommodation (after a possible earthquake) in Babol. Criteria were weighted using fuzzy analytic hierarchy process and weighted overlay method was also used to combine them.   Results and discussion Analyzing the results indicated that only 7% of the total study area (Babol City) is appropriate for temporary accommodation. Identified areas were examined according to other temporary accommodation standards. Finally, six sites and a total of 107 hectares (less than 4% of the study area) were identified as suitable sitesfor temporary accommodation. With a very large area (37 hectares) and full access to water, electricity and gas facilities,the first site is locatednear eastern beltway of Baboland Lotus PondRecreational Complex. The second proposed site is a 11hectarevacant arealocated in the northeastern part of Babol City, between Ramenet and Pari Kola Villages. With a total area of 22 hectares,the third proposed site is located in the southeast of Babol City and near BabolQa’emShahr Road. Unlike the previous three sites, the fourth proposed site is located almost inside the city. It is a vacant 5hectarearea in the northern side of the Motamedi Martyrs’ Cemetery. The next site, also located inside the city, is Aminian Dormitory (Noushirovani University of Technology) with a total area of 4 hectares. Although the last proposed site was ranked lower than the other five sites in the final analysis, it has the highest score among available sites inwestern side of Babol river. With a total area of 28 hectares, this site is located within a short distance of Imam Khamenei Highway.   Conclusion According to the international standards, per capita area for temporary accommodation is approximately 4 m2. Therefore,with a population of about 250,217,Babol needs an average space of 100 hectares for temporary accommodation. Although, the proposed space for temporary accommodation (107 hectares) in Babol almost equals the required space (100 hectares), with the present rate of population growth inBabol, increasedconstructions, and consequently, reduction of appropriate space for temporary accommodation, Babol will definitely face a shortage of suitable space for temporary accommodation of earthquake victimsin near future. Moreover, the spatial distribution of suitable sites for temporary accommodation is not reasonable, as most of the suitable sites are located in the eastern part and within the boundaries of the city. While, these sites are expected to be scattered throughout the city with an equal access for all residents.Finally, it can be concluded that temporary accommodation of earthquake victimswas not considered in urban planning of Babol, and as a result, the city does not have a suitable status regarding temporary accommodation of earthquake victims.