نوع مقاله : پژوهشی

نویسندگان

• مژگان انتظاری ¹
• طاهره جلیلیان ²

¹ دانشیار، گروه جغرافیای دانشگاه اصفهان، اصفهان، ایران (نویسنده‌ی مسئول)

² دانشجوی دکترای ژئومورفولوژی دانشگاه اصفهان، اصفهان، ایران.

چکیده

چکیده  
زمین لغزش یکی از مخاطرات ژئومورفولوژیکی از نوع حرکات دامنه ­ای با خسارت­های اکولوژیکی و اقتصادی بالا می­باشد. اولویت­ بندی زیرحوضه­ های یک حوضه­ ی آبخیز براساس پتانـسیل وقوع زمین لغزش، با هدف تعیین اولویت در سیاست­ گذاری­ ها و اقدامات مدیریتی می­تواند نقش مهمی در مدیریت بهینه ­ی آبخیز­ها داشته باشد. در تحقیق حاضر از روش تصمیم­ گیری چندمعیاره (الکترا) به منظور اولویت­ بندی زیرحوضه ­های آبخیز استان کرمانشاه از نظر ریسک خطر وقوع زمین­ لغزش استفاده شده است. معیار­های در نظر گرفته شده، شامل ده معیار مختلف شامل شیب، جهت شیب، ارتفاع، تراکم آبراهه، تراکم گسل، دما، بارش، زمین­ شناسی، کاربری و تراکم گسل است که از معیار­های مهم و تأثیر­گذار بر وقوع زمین­ لغزش هستند. وزن معیار­ها بر اساس مدل آنتروپی آنها به دست آمده و با استفاده از مدل الکترا شش زیرحوضه­ ی آبخیز در استان اولویت­ بندی، بررسی و سپس نقشه­ ی اولویت­ بندی این شش زیرحوضه­ ی آبخیز تهیه شد. تهیه­ ی نقشه­ ی اولویت­ بندی این امکان را فراهم مـی­سازد که مناطق آسیب­پذیر شناسایی و در برنامه ­ریزی محیطی مد نظر قرار گیرند. نقشه­ ی اولویت­ بندی منطقه ­ی مورد نظر نشان می­دهد که زیرحوضه­ ی ریزه ­وند ماهیدشت در اولویت اول و زیرحوضه­ ی کنگیر در اولویت آخر قرار دارند. به­ گونه ­ای که براساس نتایج به دست آمده حدود 34 درصد لغزش­ های منطقه در زیرحوضه­ ی ریزه­ وند ماهیدشت رخ داده که علت اصلی آن تکتونیک و جنس سازند­های سطحی است. در نتیجه این منطقه از لحاظ ضرورت انجام اقدامات مدیریتی در اولویت است.

تازه های تحقیق

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کلیدواژه‌ها

• کلمات کلیدی: زمین لغزش
• مخاطرات
• حوضه ی آبخیز
• انتروپی
• تصمیم گیری چندمعیاره

20.1001.1.23833254.1398.6.18.2.1

عنوان مقاله [English]

Ranking Sub Watersheds Based on Landside Hazard in Kermanshah Province (Iran) Using ELECTRE I

نویسندگان [English]

• Mojgan Entezari ¹
• Tahere Jalilian ²

¹ - Assistant Professor, Department of Geography, University of Isfahan, Iran, (Corresponding Author),

² - Ph.D Candidate in Geomorphology, University of Isfahan, Iran.

چکیده [English]

Introduction
Landslide as a natural hazard is very dangerous especially in mountainous areas. It results in loss of human life and property around the world. In spite of the progress in identifying, measuring, predicting, and landslide warning systems, the damage caused by landslides is still increasing worldwide. Therefore, given the importance of the problem, the most important managerial goals include favorable sustainable development in watershed and urban management, and the prediction and controlling of landslide with the aim of reducing its dangers. Indeed, many landslide damages are caused due to not observing correct principles of residential development, dam construction, and construction of roads and facilities. Consequently, the identification of the areas prone to landslide has a great importance for executive organizations. Indeed, the mentioned organizations knowing the location of these areas, they should certainly prevent structure construction in these areas as much as possible. In addition, if it is necessary, they should consider required technical tips and arrangements with more precision. According to the cost of performance, prioritizing the sub basins is very important. Decision making methods is an effective tool to deal with issues that may be created and in this context it has a lot of use. In recent years, attention to the ranking methods in environmental studies have been increased,

 

especially in natural hazards risk management. In this paper, considering the importance and efficiency of the non-ranked ELECTRE-1 method and its non-compensatory nature, we tried to apply this method in the prioritization of landslide risk assessment in six sub-watersheds at Kermanshah province based on the factors and indicators affecting a landslide. The main objectives of the current research were: (1) identifying the main factors affecting the landslides occurrence in the study area, (2) prioritization of the watersheds based on the risk of landslide occurrences, and (3) introducing critical watersheds regarding landslide occurrence.
Methodology
This method, like other decision-making models, is applicable to choosing the best option among others. And like the TOPSIS model, it prioritizes or ranks options by various criteria. In the ELECTRE-1 method, the weight of the criteria should also be calculated for each option.
Landslide risk assessment options for the study period are Mahidshat basin, Deira, Kanekabod, Tajrakbadre, Kangir basin, and Chika basin.
In general, there are various indicators for assessing the factors affecting the occurrence of landslides in the basins. According to the survey of location of the study area, of various factors affecting the occurrence of landslide, lithological factors, elevation, slope, slope direction, fault density, drainage density, congestion, land use, temperature, precipitation, and slip density were selected as effective factors.
-ELECTREmodel
For the first time, it was developed by Roy (1968) in a situation where real criteria and limited privileged relationships were given. Due to the complexity and high volume of computations, the algorithm of the model was programmed in EXCEL software and the values of each step were obtained.

 
Discussion and Conclusion
In this research, a multi-criteria decision-making technique was used to map areas susceptible to landslide. To do so, the factors affecting the slope sensitivity to landslide were collected. Then, to apply ELECTERE I technique to rank the sensitivity of the selected sub watersheds to the landslide, the following steps were consecutively taken. 1) The Performance matrix was created to determine the weights of the criteria. 2) The Normalization and Non-normalization matrices were formed. 3) The Harmonious and Inharmonious matrices along with the Coordinated and Uncoordinated effective matrices were obtained. 4) The final Dominance matrix was calculated. The results suggested that among the selected sub watersheds, Mahidasht Rezevand basin ranked the first having the highest vulnerability to landslide occurrence. BadraTjrk and Chika basins respectively ranked the second and the third. Deira and Kanekabod basins shared the forth rank. Finally, Kangir basin was the least likely basin to suffer from landslide incident. The susceptibility maps of the studied basins together with field surveys confirmed the proper application of ELECTRE method for ranking the sub watersheds based on landside risk. Fig 2 indicates that over 36 percent of the landslides have occurred in the high risk area. The proposed method and findings of this study are invaluable for practitioners and future academic studies.

کلیدواژه‌ها [English]

• Keywords: Landslide
• Shannon entropy model
• Multi-criteria decision making
• ELECTRE model
• Kermanshah province