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Abolfazl Ghanbari, Fariba Karami, Mohammad Ali Saleki,
Volume 4, Issue 1 (4-2017)

One of the geomorphologic issues that many human activities affect is the landslides. Natural factors and human activities on the other hand, these events are triggered. Landslide one of the most active hazards are natural processes that lead to erosion and changes in the landscape. Iran is a predominantly mountainous topography, seismic activity and high landslide, diverse climatic and geological conditions of natural conditions for a wide range of slip is important. Located in second place in the sector of industry, population of 1695094 people, proximity to major faults of Tabriz and occurrence Landslides of different city of Tabriz, the city has become one of the most dangerous cities in the environmental hazards, especially landslide. In these circumstances and completed a comprehensive review and a detailed zoning of land for landslide susceptibility seems absolutely necessary. The purpose of the present paper, the occurrence of landslide susceptibility assessment and mapping potential occurrence of landslides in the city of Tabriz in this range.

     This research of the type applied- development research and of the research method is descriptive - analytic. In this study, using a variety of sources including satellite imagery, aerial photography, global positioning system (GPS) and field studies landslide occurred in the study area were identified and these data were analyzed using the software ILWIS and use of library studies and expert opinions should identify the criteria and sub-criteria and range were classified. Then, using fuzzy TOPSIS model, the importance of the criteria and sub-criteria specified in pixel units and finally combining fuzzy-TOPSIS model and overlapping functions in ARC / GIS final map was extracted.

Geomorphologic and lithology conditions of the city with its mountainous location where the trigger landslides. The final results indicate that over 30% of the areas of the city of Tabriz are medium to high risk that this areas of land in the north and northeast is sparse. The accuracy of the final map and the map of the distribution of faults and the accuracy of the study proved to be that hazardous zones roughly corresponding to the final map lapses occurred. So we can conclude that the method and the model presented in this paper is an effective method for landslide hazard zonation within the cities.

Armaghan Nickandish, Soolmaz Dashti, Gholamreza Sabzghabaei,
Volume 5, Issue 2 (9-2018)

The most important role that the managed areas will play to attain sustainable development goals would be protecting ecosystem and genetic diversity to achieve the scientific, aesthetics, social and economic potential benefits in future. Proper management of protected areas requires a full understanding of the present conditions, detailed and exact implementation, planning, regular monitoring and risks changes detection in protected areas to understand how are they, how they would effect on nature, recovery and rehabilitation processes and to protect them in long term is very important. Karkhe National Park and protected area is one of the most valuable and most strategic areas in the country that can be protected. This study aimed to identify and analyze threatening risks in Karkhe protected area and national park. The Study area is located with an area of ​​15828 hectares (sum of national park and protected area) on both side of Karkhe river in Khuzestan province. In this research based on field visits and using the Delphi technique, that there were 15 experts and specialist joint it, 28 risks in two terms of the natural and anthropogenic environment (physicochemical, biological, economical, social and cultural) are identified. Then to order the identified risks, The TOPSIS method was used according to the three fectors, severity, probability and sensitivity of the host environment. The results showed that the risk of lack of conservative officer by closeness coefficient (CC) 1 is the highest risk in the area and The risk of soil pollution with heavy metals by closeness coefficient 0.149 is the lowest priority. The most obtain risks has been socio-economic risks. After ordering the environmental risks was found that existing risks in the region has been in a considerable level. Finally, strategies to control risk in the region was presented. As a result, management solutions should be provided to reduce, control, or eliminate the most important risks. In the meantime, strengthening the existing environmental laws and the necessary guarantees for their implementation seems necessary.

Samira Jafariazar, Gholam Reza Sabzghabaei, Mortaza Tavakoly, Soolmaz Dashti,
Volume 5, Issue 4 (3-2019)

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).


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.

Ali Eshghei, Hossein Nazmfar, Ata Gafari,
Volume 7, Issue 2 (8-2020)

Spatial analysis physical resiliency City Earthquake Model Condorcet
Case study: ten districts of the region one of Tehran
Earthquake as one of the most devastating and destructive natural hazards; especially in developing countries, it has been a long time ago With the collapse of buildings and urban infrastructure, Imports a lot of damage to property and assets in urban areas and around them. In response to this, international organizations' strategies to mitigate disasters have made their societies resilient to natural disasters. And considers it within the framework of the Higgo for the years 2005-2015. In fact, the goal of this approach is to reduce the vulnerability of cities and to strengthen citizens' abilities to deal with the dangers of threats such as natural disasters. Considering that the area of ​​a Tehran city due to its proximity to faults such as Mashaa fault, North Tehran fault Also, the effects of faults in and around the region such as Niavaran fault, Mahmoodieh fault and Darabad fault (Banamieh) are located in a region with a high seismic hazard. Assessment of resilience of the region to earthquake risk and resilience of the region In order to reduce the risks of earthquakes in this area is very important. Accordingly, the present study was conducted with the aim of assessing the resilience situation of the 10th district of Tehran municipality district against earthquake.
The method of this research is descriptive-analytical with a purposeful purpose. The research area of ​​the 10th Region is a municipality of Tehran. The raw data used by the Tehran Municipality Information Technology Organization has been obtained. To determine the relative importance of each component used in research According to experts from the Urban Planning Area, the Network Analysis Process (ANP) has been used in the form of Super Decisions software. Then, to rank 10 areas of a Tehran municipality district against earthquake, Multi-criteria decision making models (MCDMs) including TOPSIS, VIKOR, HAW and SAW models have been used. Considering that different methods have been used to rank the areas Different results have been achieved, to overcome the contradictions between the various ratings of the regions in each of the models,
and a single result has been used to rank the areas of the congregation's integrated model.
Finally, in order to speak, the results of the model used in the ArcGIS environment were mapped.
In this research, for the spatial analysis of the resilience of the 10 district areas of a Tehran municipality from the results four models (TOPSIS, VIKOR, HAW and SAW) were used. Based on the results of the TOPSIS technique, areas 8, 3 and 2 of resilience are large, areas 7 and 4 of the moderate resilience, Areas 5, 1, 6 and 10 have low resilience and area 9 has very little resilience against the earthquake. Based on the results of the VIKOR model, areas 3 and 4 of the resilience, regions 2, 7, 5, 9, 8, 6 and 10 of the moderate resilience Medium and area one have low resilience against earthquake. Based on the results of the HAW model, area 3 of the high resilience, regions 2, 7, 8 and 4 of the moderate resilience and areas 10, 1, 6 and 9 are of low resilience. In this model, no area has been found to be very resilient. Based on the results of the SAW model, regions 3, 2, 8, and 7 are in the range of many resiliences, regions 5 and 4 in the moderate resilience range, Area 9 is in the low resilience range and areas 10, 6 and 1 are in the low resilience range against earthquakes.

In this study, we evaluated the resilience situation in the districts of Tehran municipality district in an earthquake Multi-criteria decision-making methods including TOPSIS, VIKOR, HAW and SAW were used, Then a CONDORCET integrated model was used to achieve a single result of these analyzes. The results of the Canadian model, which is the result of a combination of the final results of the models (Tapis, VIKOR, HAW and SAW), show that Areas 2, 4, 5, and 3 are of high resilience, areas 7, 8 and 1 of the moderate resilience, 10 and 6 of the resilience, and area 9 of the resilience is very low against earthquakes. Which should be prioritized in future plans. Although it is possible to assess the vulnerability of urban areas by using different models and mapping them in the region's resilience to the earthquake crisis, a significant part of post-crisis casualties fell but this will not be achieved until the authorities are seriously determined.
Keywords: Resilience, Earthquake, Multi-criteria Decision Making Methods, Tehran Municipality Area

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