Iran is a wide and great land that is located on Alps earthquake belt of Himalaya. Great part of the urban and village residency of the country have been exposed to the intensive earthquake and destructive. Sarab city with several other cities, including Tehran, Karaj, Abyek, Qazvin, Roudbar, Khalkhal ,Tabriz, Marand and khoy are located on Earthquake belt that Earthquake risk is too high. In Eastern-Azerbaijan and Sarab, potential earthquake risk is very high, since there are a lot of active faults and historical evidences show the horrific and destructive earthquakes. Sarab city located in the Sarab plain which have abundant faults in various directions. Earthquake as a natural phenomenon doesn’t have good results but what can make it a catastrophe, is the lack of prevention from its effects and no preparation for coping with its aftermaths. The unsuitable establishment of structural elements and urban land-uses and atypical web of urban open spaces, the old ages of and low quality of the structures in the decayed area of the factors like this have main role in the increasing the amount of damage entered to the cities against to the earthquake. It is necessary to reduce the vulnerability of the cities against the earthquake and to consider it as one of the main goals of the urban planning. Main objective of this paper is planning for reduction of damages arising out of earthquake in Sarab city. The study area is the Sarab city with four urban regions and 15 districts. The present research is an applied study. For this purpose, considering the goal of the study, nine factors including the type of structural materials, the quality of the buildings, the number of the floors, the population density, pedestrian width , the availability of open space and distance from river were identified and evaluated, so that for each of the indicators or factors, one layer of map with shp format was produced and then in an analytical hierarchy process and weighting to the variables, layers overlaying operation using available analytical functions was implemented in Arc Gis software. Finally the vulnerability map of the Sarab city was prepared. According to the results of AHP model, it is concluded that Sarab in terms of vulnerability has no appropriate status against earthquake risk so that the whole Sarab city is vulnerable to earthquake, but some of its neighborhoods due to low quality of buildings and vulnerability of streets network and inaccessibility to open areas and excessive compression are more vulnerable. Deteriorated urban area is one of the most vulnerable parts of the Sarab city during the occurrence of the earthquake. Therefore, to reduce the health and wealth damages which can cause by the earthquake in the city.
Environmental hazards are considered as one of the main obstacles for achieving sustainable human settlements development (particularly in rural areas). Today, with a new look at crisis management, using all managerial, organizational and planning accomplishments before the crisis, is an essential and rational concern. Rural settlements of the country along with cities always are threatened by a variety of environmental hazards, but what makes these spaces different from the cities is the high-intensity of vulnerability due to its physical decay texture. In this regard, one of the key elements in confronting the possible crisis that must be taken into account is the crisis management bases in which all prevention, preparedness and response measures, including disaster relief, temporary accommodation for the injured, etc. is provided and minimizes the consequences of potential crisis. Being located in the Kahrizak fault zone and the placement of hazardous industries in this region, is the main reason for selecting Kahrizak district as a study area in this research. To achieve goals of constructing crisis management bases which indeed is the tactic ability of crisis management system (CMS), it is required to set the site selection criteria and standards for constructing them in such a way that provide more operational activities and develop the level of their impacts. In this regard, in the first step, the final criteria for site selection of crisis management base were selected after reviewing previous studies. Then, after surveying the experts and also the localization of criteria on the basis of area condition, seventeen final criteria were determined. For quantitative criteria, data were collected through organizations and reference centers and for a single qualitative criterion (cultural convergence), the questionnaire instrument used in gathering data. After collecting data using library and field methods, a combination of two models: fuzzy logic and hierarchical analysis process (AHP) applied for optimal location of crisis management base. To determine the impact level of each criterion in the site selection process in two above-mentioned models, the standards for each of the seventeen criteria was determined with the help of combination method. The standards of some of the criteria determined using the standards in related organizations and some other standards proposed by experts and also through the localization by the researcher. Afterward, initially fuzzy standardized common scale maps produced from all information layers in a raster format. Then selected criteria by experts in the format of AHP model were compared with each other through pairwise comparison method. As a result of this comparison, the weight of criteria was determined which indicates the preference degree of each criterion over the others. At last, all standardized (fuzzified) layers multiplied in each of the final weight resulting from Analytical Hierarchy Model and in total converted into weighted fuzzy layers. In the next step, following the process of fuzzy model, fuzzy addition and multiplication operators were applied on output layers. Finally, to modify the layer resulting from fuzzy addition and multiplication, the Gamma operator was used. As such, after producing layers of different fuzzy gammas, essential assessment was conducted for selecting appropriate and ideal gamma. In order to do this, produced layers of each fuzzy gammas were compared with the study area for optimal location and the establishment of crisis management base. Since the gamma 0.9 had the most conformity to suitable zone in the layers of study area, it was selected as the appropriate gamma. However, to ensure the selected location, field study was conducted. According to the research findings, the following conclusions were obtained: Site selection criteria for rural crisis management base not only has an environmental essence (built and natural), but socio –economic criteria are important as well Effective criteria for site selection of rural crisis management base, affected by regional and local requirements are not the same. Localization of criteria is a necessity that should be considered in site selection. Standards based on site selection criteria depending on the type of services, goals and location at multiple spatial levels (regional, local, urban and rural) is different: in the other words one size does not fit all Site selection is not only based on the location within overlaying information layers by using the models, but the final choice is done after field evaluation and visit.
Resilience are concepts that are finding increasing currency in several fields of research as well as in various policy and practitioner communities engaged in global environmental change science, climate change, sustainability science, disaster risk-reduction and famine interventions (Vogel, et.al, 2007). Where the risk is a probability of damage, injury, liability, loss, or any other negative occurrence that is caused by external or internal vulnerabilities, and that may be avoided through preemptive action (Benson, et.al, 2004). Among natural disasters, earthquakes, due to the unpredictable nature of these events, are one of the most destructive. Iran is one of the most earthquake-prone countries in the world that its cities most affected by this phenomenon. Among the cities of Iran, Tehran, as the country's first metropolis, due to dense population, poor physical development, structural density, and lack of standards, is potentially facing a serious threat. The purpose of this study is to investigate the spatial flexibility of Tehran over the region 12 after the earthquake incidence.
The present study is dealt with the data preparing and analysis using geospatial methods. The several geospatial data such as Peak Ground Acceleration (AGA) map, urban structure, infrastructure and population collected from Tehran Disaster Management Center were provided and analysis based some GIS known algorithms. In other to urban spatial resilience zonation the AHP (analytical Hierarchy Process) was implemented to generation risk map. Finally OWA (Ordered Weighted Average) method was implemented in order to Production spatial flexibility map of earthquake incidence over the District 12 of Tehran. AHP model uses of priorities straight experts, but OWA provides of control the level of compensation and risk-taking in a decision. Using the conceptual of fuzzy quantifier with OWA makes the qualitative data analysis enter to decision.
According to flexibility of the final map with fuzzy operator (All) equivalent to the operator MIN, the worst result Was obtained and resulting the highest risk and lowest flexibility respectively (Districts Nos. 2,12,7,8 and 11).By taking all the criteria of a criterion without compensation by other criteria as "non-risk" is obtained .
Map obtained with fuzzy operator (Half) has the high potential to provide suitable options, because in addition to integration criteria the importance of each parameter based on the weight given to the criteria are considered. In this map Districts Nos.2.6 and 8 (Baharestan, Emamzadeyahya and Sanglajedarkhangah) respectively were most Risk to earthquakes and therefore less flexibility to the earthquake. The map obtained with the fuzzy operator "Atleast one" is equivalent to MAX operator districts Nos. 2,12,7 and 8 (Baharestan ,DarvazehGhar of Shush,Abshardardar and Sanglajedarkhangah) respectively were most Risk to earthquakes and therefore less flexibility to the earthquake.
The fuzzy conceptual map quantifier showed that districts Nos. 2 and 12 (Baharestan and DarvazehGhar of Shush) were most vulnerable and therefore less flexibility to the earthquake as final results.
Introduction: Wetland ecosystems, especially marine coastal wetlands of the most important and also the most vulnerable are the world's environmental resources. Which has always been sensitive to the fragility of coastal areas, high population density and intensive human activities are faced with the threat of destruction. Based on this, monitoring the trend of the changes in wetlands and their surrounding lands can be effective in the management of these valuable ecosystems. Investigating the environmental risk is a suitable instrument for evaluating and ensuring understanding of the relationships between stressor factors and environmental effects especially in wetland ecosystems. In general, application of methods of evaluating environmental risk is one of the important tools in studying environmental management along with identifying and mitigating potential environmental damaging factors in wetland regions in order to achieve sustainable development. Today, multi-criteria decision-making methods are employed in evaluating the risk in many studies.This study is based on multi-criteria decision-making methods to identify and analyze the risks threatening Tyab- Minab International wetland located in Hormozgan province was conducted.
Materials and methods: Based on the methodology to identify and prioritize risks Delphi, AHP and TOPSIS techniques were used to determine the risk priority number. In the first phase of this study, to identify and screen the main criteria of project selection, Delphi method was used. In this study, the panel of interest was determined based on a combination of experts with different expertise and out of a sample of 20 individuals, in which experts with various expertise gave a score from 1 to 5 (Likert scale) to each criterion. In this way, 32 criteria were identified as the most important and considerable risk for Minab Wetland and further proceeded to the second phase for prioritization and analysis. In this stage, multi-criteria decision-making methods were used, in which hierarchical analysis process was employed for prioritizing the criteria using Expert Choice 11 software. The indices of risk evaluation including the impact intensity, incidence probability, and the sensitivity of the receptive environment in environmental risk evaluation of wetlands do not have an equal value and significance. For this purpose, to weight the factors effective in estimating risk level and for prioritization of risk options, the technique for order of preference by similarly to ideal solution (TOPSIS) and Excel software were benefited from for calculations. The spectrum of scoring to each of the indices of incidence probability, impact intensity, and the sensitivity of the receiving environment was chosen from very low (1) to very high (9) based on hour spectrum. Following investigation of the types and frequency of indices along with the method of score determination of these indices, three indices of risk intensity (C1), risk incidence probability (C2), and the sensitivity of the receiving environment (C3) were chosen for risk ranking using TOPSIS model. Next, after determination of risk priority number using TOPSIS, the risk levels were calculated and evaluated using normal distribution method for each risk. To determine the degree of risk-taking, risks are organized in a descending order, where the elements of the number of the class and the length of the class are determined based on Relations 1 and 2 (n is the number of risks). Next, the risks are categorized based on these classes. Considering the concept of ALARP, the risks under investigation are divided into high risks, medium risks, and low risks. In this study, considering the number and length of classes, the studied risks were categorized in six levels (critical, intolerable, considerable, medium, tolerable, and trivial risks).
(2)
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(1)
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the number of classes=1+3.3 log (n)
the length of the classes= the greatest risk value - the smallest risk value/the number of classes
Results and discussion: In the first step, the final indices of the wetland's environmental risk were identified and the development of hierarchical tree and classification of the risks threatening wetlands along with their incidence probability in two groups of natural and environmental criteria was performed. Eventually, the final weight of criteria resulting from paired comparisons was obtained in Expert Choice 11 to achieve the score of incidence probability of each risk. Based on the results, among the natural, social, economic, physiochemical, biological, and cultural criteria, drought and climate change, increase urban and rural development, Smugling of fuel, oil pollution, reduce the density of vegetation, indiscriminate exploitation of groundwater were of high priority. The results obtained from ranking the the risks threatening Minab Wetland using TOPSIS suggest that oil pollution, dam construction upstream, persistent drought and climate change, and sometimes alcohol and fuel smuggling and illegal overfishing the priorities are first to fifth. Also Results showed that the respectively based on (Cj+) oil pollution (0/9109), dam construction (0/8121), the drought and climate changes (0/8063) and the smuggling of fuel (0/7520) are in Unbearable level.
Overall, the results indicated that same as this research, wetland ecosystems are subject to many threatening factors, resulting in ecological imbalance and abnormal appearance of the wetland, putting the wetland entity into danger of extinction in terms of fauna and flora.
Conclusion: Nowadays, for assessment of environmental risk, various methods are used, each of which has positive and negative points given the studied environment and the conditions governing it. Therefore, one cannot reject or approve one method with total confidence. By employing novel methods in risk evaluation, the intensity of risk incidences and, in turn, the damages and losses incurred to the environment can be prevented or at least mitigated. Further, it is also possible to move in line with proper and optimal management of environmental resources, especially wetlands and with sustainable development. Undoubtedly, understanding and recognition of the factors threatening wetlands, according to the importance and the impact of them, Prevent and cope with the threats and accurate project preparation and implementation of wetland conservation plans and environmental management.
Developing urbanization and changing hydrological conditions of natural streams increases the flooding risk. This study tries to do flood hazard zoning in the Ilam city and determine the critical area of the urban regions against flooding by using AHP method and GIS environment. For this purpose, the parameters of the curve number, height, distance from the river, geology, land use, population, slope, soil, building density, worn texture buildings and accumulated flow as effective parameters in flooding hazard in Ilam city selected and of these parameters weighted by using Expert Choice software. The result of the Expert Choice software is transferred to the environment of GIS software and flood hazard map of study area prepared. Results of the study and flood hazard map show that areas with very low-risk, low risk, intermediate-risk, high-risk and very high-risk form the 0.8%, 8.5%, 49.6%, 32.54% and 8.56% of the of Ilam city area, respectively. Also, the central area of the city has the highest risk and the probability of occurrence of the flood due to the high density of population and residential areas in this area and its proximity to the seasonal rivers and old part of the city. Therefore, by examining the results of Expert Choice software, it is possible to identify the most effective factors in the occurrence of flood risk and prioritize them to address management solutions to eliminate or mitigate the effects of these factors.
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