@article { author = {Hejazizadeh, Zahra and Hosseini, Sayyed Mohammad and Karbalaee Dorei, Alireza}, title = {The Simulation of Climate Change in Semnan Province with Scenarios of Atmospheric General Circulation Model (Hadcm3)}, journal = {Journal of Geography and Environmental Hazards}, volume = {4}, number = {3}, pages = {1-24}, year = {2015}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v4i3.44214}, abstract = {1. Introduction Climatic change is one of the most important challenges human beings have confronted with in recent centuries due to its severe effects on water resources, agriculture, energy, tourism and even human bioclimatic. Developing strategies, making decisions with awareness about water consumption in different parts in the future, and available water resources management require climatic change information (i.e. precipitation and temperature) which can be directly used with hydrology and climatology models. In recent years, climate prediction models have been used for numerous purposes such as the generation of climate data using different scenarios related to greenhouse gases in general circulation models. By using these models, the output of general circulation models (GCM) can be examined at micro-scales. One of these models is called LARS-WG, which has received considerable attention from the researchers in Iran or elsewhere. 2. Case Study Using the LAR model, we have collected climate data from among four synoptic stations from their establishment until 2010. Data used in this research including minimum and maximum temperature as well as precipitation were daily recorded. To generate the precipitation values, LAR (a well-known generator model of random data for climatic status) was used. Likewise, the minimum and maximum temperature in every station of Semnan Province was used for both basic and future periods.. In addition,, to investigate the LAR model in simulating, the Ground Truth average bias and absolute error have been calculated for the simulated data and truth in the investigated period: 3. Conclusion In these scenarios, there was almost full coverage between the Ground Truth and simulated data. In A1B scenario, more stations bring more assurance in simulating data in winter and spring. The maximum observed and simulated precipitation was calculated by Hadcm3 model scenario in all Semnan stations in March. The minimum precipitation in Shahrood and Biarjmand stations was in July and August, respectively. As for Garmsar and Semnan stations, the minimum precipitation was in September. All stations in January had the least minimum and maximum temperature in January, whereas they had the most minimum and maximum temperature in July.}, keywords = {Downscaling,Atmospheric general circulation model,Climate change,LARS-WG,Semnan Province}, title_fa = {شبیه سازی متغیرهای اقلیمی استان سمنان با سناریوهای مدل گردش عمومی جو (hadcm3)}, abstract_fa = {امروزه مدل سازی و برآورد فراسنج های آب‌وهوا شناختی به سبب گستردگی تغییرات اقلیمی، افکار اغلب اندیشمندان را به خود مشغول کرده است. ازاین رو در این پژوهش برای دستیابی به بازتولید داده‌های اقلیمی و مقایسه سناریوهای مدل گردش عمومی جو از سه متغیر مهم اقلیمی شامل بارش، دمای کمینه و دمای بیشینه در استان سمنان استفاده شده است. بازۀ زمانی داده های این فراسنج ها به‌صورت روزانه است که از بدو تأسیس چهار ایستگاه همدید بیارجمند، شاهرود، گرمسار و سمنان تا سال 2010 را شامل می‌شود و این دوره زمانی به‌عنوان دوره پایه، مورد بررسی قرارگرفته است. همچنین برای مقایسه نتایج به‌دست‌آمده از مدل با داده‌های مشاهداتی از سناریوهای B1، A2 وA1B در مدل HadCM3 تحت برنامه ARS-WG در دوره زمانی 2011 تا 2030 به‌عنوان دوره آتی شبیه سازی بهره گرفته شد. درنهایت نقشه های پهنه بندی مقادیر مشاهداتی و مقادیر شبیه‌سازی‌شده این متغیرها ترسیم شد. نتایج حاکی از این است که به‌طورکلی سناریوهای مورد استفاده در مدل HadCM3، قابلیت بالایی در شبیه‌سازی سری‌های زمانی متغیرهای هواشناسی در این استان را دارا می باشد و انطباق و همپوشانی نسبتاً بالایی بین داده های مشاهداتی در دوره پایه با داده های شبیه‌سازی‌شده در آینده وجود دارد؛ اما سناریوی A1B در اغلب ایستگاه های مورد بررسی، توانمندی چشمگیرتری در شبیه سازی داده ها به‌ویژه در سه ماهه زمستان و بهار دارد. همچنین نتایج نشان داد که بیشترین میزان بارش مشاهداتی و شبیه‌سازی‌شده توسط سناریوها مربوط به ماه مارس و بیشترین دمای کمینه و دمای بیشینه از آن ژولای است. همچنین نقشه‌های پهنه بندی داده‌های مشاهداتی و مدل سازی شده متغیرهای مورد بررسی حاکی از این است که کاهش میزان بارش در سمت شرق، مرکز و شمال استان کاملاً مشهود است و دمای کمینه و بیشینه نیز در سمت شرق و شمال این استان، افزایش قابل توجهی خواهد داشت.}, keywords_fa = {ریزمقیاس نمایی,گردش عمومی جو,تغییر اقلیم,مدل LARS-WG,استان سمنان}, url = {https://geoeh.um.ac.ir/article_28790.html}, eprint = {https://geoeh.um.ac.ir/article_28790_f7b72d9a2e6fbe4b62dd7ca7958e39a5.pdf} } @article { author = {Kazemi, Rahim and Davoodi, Mohammad Hadi}, title = {An Assessment of the Effect of Calcium Dosage Injection on the Mechanical Strength of Fine Grain Soils}, journal = {Journal of Geography and Environmental Hazards}, volume = {4}, number = {3}, pages = {25-38}, year = {2015}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v4i3.40157}, abstract = {1. Introduction Adding lime to increase the geotechnical characteristics of fine-grained soils, to achieve different goals always been done from ancient time. There are many techniques for stabilizing unstable slopes, among them lime treatment is a quick, simple and cost-effective operation that can be incorporated into any unstable slopes. Some scientific techniques of soil treatment have been introduced by Bell (1996). The effect of lime on maximum compressive strength were studied by Indraratna (1996). He concluded that the addition of only 2% of lime results in a 50% increase in compressive strength and if this amount increases to the 5% of lime, the increase is doubled. Although lime stabilizes the soil rapidly after the treatment, the mechanical properties and strength of soil change over a long period of time (Bell, 1996; Sivapullaiah, Sridharan, & Ramesh, 2000). Recently a new method has been developed by which lime is injected into soil in the form of saturated solution. As it penetrates into the soil due to the gravity, it improves soil strength through pozzolanic reaction (Davoodi, 2007). Limited studies have been conducted to investigate the suitability of using saturated lime solution in slope stability. Optimum concentrations of lime solution and lime dosage were investigated by Pui Ling (2005) and Pedarla, Chittoori, Puppala, Hoyos, & Saride, (2010). Moreover, it is known by the studies of Khelifa (2010) that the curing time influences the physical properties of soil stabilized by lime, and considerably increases the shear strength of cohesive soils stabilized by lime. This study intends to assess the effect of calcium dosage on uniaxial strength of clayey soils stabilized by saturated lime solution in order to be applied in unstable slope stability and sediment control. 2. Material and Methods Soil: The clay soil chosen in this study was a fine grain soil, classified as ML–CL in the Unified Soil Classification System, underwent laboratory tests. The soil properties are as follow. Maximum dry mass density of approximately 1.88 g/cm3 at optimum moisture content of approximately 10.9%.The specific gravities of soil, Liquid limit and Plastic Limit were 2.63, 21.64, and 18.92 respectively. 3. Saturated Lime Solution The lime used for preparing the saturated lime solution was a commercially available lime typically used for construction purposes. The simple method for preparing the saturated lime solution is to thoroughly stir 5 grams of hydrated lime into one liter of water, allowing the excess to settle; the excess in the bottom will ensure that the solution remains saturated. 4. Methods Laboratory tests consisting of compaction and uniaxial strength were conducted on the specimens with a controlled humidity and temperature. Each specimen was compacted at optimum moisture content and maximum dry density and after preparation of specimens, 15 soil samples in five set were placed in saturated lime solution for 48 hours, then they were kept in the controlled chambers for a period of, 3, 7, 28, and 60 days and then mechanical properties were tested. One set for 48 hours only influenced by the water as a representative sample and comparison. By measuring the amount of calcium ions in the sample before and after the treatment, the calcium ion consumption was computed. 5. Results and Discussion It is generally accepted that the penetration of lime solution in clayey based soils readily lead to the pozzolanic reaction that may cause increasing geotechnical characteristics. Different values of calcium consumption in the specimen after the mixture of lime solution with soil specimen showed the evolution of lime consumption with curing time. The Initial consumption of lime can be used as an indication of the minimum quantity of lime that must be added to the soil in order to achieve a significant change in soil properties in short time. In this study, determination of this minimum percentage of lime is based on measurement of calcium ion concentration in soils before and after solution affect. Average calcium consumption for short term treatment (3 day) was found 27 milligram per liter, for 7 day 34 milligram per liter, 28 days curing period 45 milligrams per liter and for 60 days curing period also 45 were found. This demonstrates that there is no important effect of lime addition after 28 days and it also demonstrates the minimum lime consumption for short term soil improvement. Uniaxial strength of specimens with 3 days curing time increased by 180% compared to the control sample. With increased calcium consumption and pozzolanic reactions, the permeability of the samples also showed a downward trend. This is due to the decrease in porosity and is due to pozzolanic reactions. 6. Conclusion By comparing the results of the absorption of calcium in the treated samples and the relationships between them as well as the relationship between the curing time and strength of the samples, it was concluded that the minimum and maximum lime needed to increase the mechanical properties of soil resistance can be calculated. Also it was concluded that the most effective curing time for injection and increasing the mechanical properties of the soils with saturated lime solution is 28 days. This study has led to the valuable insights regarding the treatment of the soil by saturated lime solution in order to sediment and landslide control}, keywords = {Uniaxial strength,Curing Time,Calcium ions,Soil stabilization}, title_fa = {ارزیابی تأثیر تزریق یون کلسیم بر مقاومت مکانیکی خاک های ریزدانه}, abstract_fa = {روش های مختلفی برای تثبیت توده های طبیعی نا پایدار وجود دارد. یکی از این روش ها افزایش پارامتر های مقاومتی خاک از طریق اصلاح کاتیونی و به روش افزودن محلول اشباع آهک تحت نیروی ثقل به خاک است. این تحقیق به ارزیابی تأثیر میزان یون کلسیم مصرف شده بر مقاومت تک محوری خاک رسی تثبیت شده با محلول اشباع آهک پرداخته است. 15 نمونه خاک با شرایط یکسان آماده شد و به مدت زمان مشابه تحت جریان محلول اشباع آهک قرار گرفت. سپس در دسته های سه تایی و در محفظه مخصوصی به لحاظ رطوبت و دما در دوره های زمانی3، 7، 28 و 60 روزه، نگهداری و سپس مورد آزمایش مقاومت فشاری تک محوری قرار گرفتند. سه نمونه فقط تحت جریان نفوذ آب قرار داده شد و از نتایج آن به عنوان نمونه شاهد استفاده گردید. با اندازه گیری میزان یون کلسیم موجود در نمونه، قبل و بعد از اصلاح، میزان یون کلسیم ترکیب شده، به دست آمد. حداقل یون کلسیم لازم برای افزایش قابل توجه مقاومت خاک، برای نمونه های دسته سه روزه و معادل 32 میلی گرم در لیتر با مقاومت نظیر 180 درصد به‌دست‌آمده است. حداکثر یون کلسیم جذب شده مربوط به نمونه های با دوره عمل آوری 28 روزه است که معادل 47 میلی گرم در لیتر و حداکثر مقاومت نظیر آن، معادل افزایش 436 درصد نسبت به نمونه شاهد به‌دست‌آمده است. حداکثر مصرف در دوره تزریق 28 روزه و عدم تغییر فاحش مصرف یون کلسیم بعدازآن، نشان دهنده آستانه میزان مؤثر یون کلسیم مورد نیاز برای دست یابی به حداکثر مقاومت است. همچنین نتیجه گیری شد که مؤثرترین مدت تزریق در فرآیند افزایش مقاومت خاک با محلول اشباع آهک، 28 روز است. همچنین مشاهده شد که نمونه های با زمان عمل آوری طولانی تر و میزان کلسیم دریافت شده بیشتر، رفتاری مشابه به رفتار سنگ از خود نشان دادند و کمترین میزان کرنش متناظر مقاومت فشاری، به میزان 2 درصد تغییر شکل نسبی، را در زمان گسیختگی از خود نشان دادند.}, keywords_fa = {مقاومت فشاری تک‌محوری,زمان نگهداشت,یون کلسیم,تثبیت خاک}, url = {https://geoeh.um.ac.ir/article_28821.html}, eprint = {https://geoeh.um.ac.ir/article_28821_0f1e9e131e4d5496cda0399c3ebcf170.pdf} } @article { author = {Asgarizadeh, Zahra and Rafiean, Mojtaba and Dadashpoor, Hashem}, title = {Empirical Model of Household's Earthquake Risk Mitigation Behaviors Using Path Analysis Method}, journal = {Journal of Geography and Environmental Hazards}, volume = {4}, number = {3}, pages = {39-60}, year = {2015}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v4i3.41900}, abstract = {1. Introduction How people manage risks and which variables influence on the process of risk management play a crucial role in providing productive urban disaster management and increasing public participation in the urban risk management programs. The purpose of this study is to better understand the motivations of residents in adopting reduction risk behaviors to protect themselves and their residents against earthquake risk. Understanding this process will help urban disaster management enhances participation in and implementation of their programs. 2. Study Area The city of Tehran, which is adjacent to several major fault lines, was selected as a case study. Mosha-Fasham Fault is in the North of the city and the South Faults and Rey Fault are the most prominent faults in the southern plains. According to the Atlas of Tehran Metropolis, Tehran has had few severe injuries in an earthquake over the past 150 years. The largest historical earthquake in the region occurred in 958 (7/7 Mw magnitude) and its distance to the center of Tehran was less than 50 kilometers. Tehran has had about 1,000 large and small earthquakes recorded within a radius of 100 km of its center. 3. Material and Methods Because earthquake risk mitigation behaviors are affected by both individual and social processes, to identify variables in this study a combination of psychological and cultural approaches were applied. We restricted our study to actual and intended behaviors. We developed a conceptual model based on the literature review. The instrument was a questionnaire with a sample size of 267 cases that was carried out from March 2013 until the end of April 2014.The questionnaire was designed with four sections. The first section includes some questions about the mediator variable of risk perception, the second section contains some questions about independent variables, the third section includes questions about the risk mitigation behavior variables as a depended variable, and the final section contains questions about demographic characteristics. To analyze the conceptual model and obtain the empirical model Path Analysis Method was used. Path Analysis was used to test the conceptual model empirically. Data were analyzed using SPSS version 20. To perform path analysis, we used linear regression analysis with the Enter method. The reliability of questions associated with earthquake risk perception in questionnaire was assessed using Cronbach's Alpha. 4. Results and Discussion In terms of reliability we found out a Cronbach's Alpha of 0.83 for the collection of earthquake risk perception questions. The result of the study demonstrated that the earthquake risk perception of households were slightly higher than the mid level (1 .05). This research showed that in spite of household perception regarding safety and risk, there is a lack of adequate consideration and effective action on the threat of earthquake up to now. The results of path analysis on the dependent variable of intended behaviors showed that four variables of risk perception, controllability, trust in urban disaster management and length of residence in Tehran had significant relationship with intended behaviors (P> .05). Among these variables, only effect of risk perception was positive. 5. Conclusion It seems that trust is an important factor that urban disaster management decision-makers should consider more and do more effort to increase public trust. As well, three variables contain age, self-efficacy and the need to be protected had a positive effect and two variables contain optimistic biases and income had a negative effect on intended behaviors through risk perception as a mediator variable. It is clear that there is a great need to provide a base in increasing public awareness and promoting their perception by the governments and authorities to reduce risks associated with earthquake in Tehran.}, keywords = {Risk perception,Risk mitigation behaviors,Earthquake in Tehran,Path analysis}, title_fa = {بررسی و تحلیل مدل تجربی رفتارهای کاهش خطر زلزله خانوارهای شهر تهران}, abstract_fa = {هدف این تحقیق، سنجش ادراک ریسک زلزله و بررسی مدل تجربی متغیرهای تأثیرگذار بر روی رفتارهای کاهش خطر زلزله خانوارهای شهر تهران است. ازآنجاکه ادراک و رفتارهای کاهش زلزله معلول هر دو فرآیندهای فردی و اجتماعی است، در این تحقیق تلفیقی از رویکردهای روانشناسی فرد‌محور و فرهنگی به کار گرفته شد. بدین‌ترتیب مدل نظری تحقیق بر اساس متغیرهای تأثیرگذار از هر دو رویکرد بر روی متغیر وابسته رفتارهای کاهش خطر زلزله شکل گرفت. همچنین رفتارهای کاهش خطر زلزله به‌صورت هر دو رفتارهای عملی و قصد برای آینده بررسی قرار شد. روش تحقیق مورد استفاده توصیفی-تحلیلی بوده است. جهت تحلیل مدل مفهومی و دستیابی به مدل تجربی از روش تحلیل مسیر استفاده شد. ابزار سنجش پرسشنامه با حجم نمونه 267 مورد بود. نتایج نشان داد که میزان ادراک ریسک خانوارها، بالاتر از میانه (1>4.71>7 با میانه نظری 4) می‌باشد. نتایج حاصل از روش تحلیل مسیر بر روی متغیر وابسته رفتارهای عملی کاهش ریسک نشان داد تنها چهار متغیر دانش نسبت به رفتارهای کاهش خطر، درآمد، سن و مالکیت بر رفتارهای عملی کاهش ریسک زلزله اثر مستقیم دارند (P>.05). علیرغم انتظار سایر متغیرهای تحقیق ارتباط معنی‌داری با متغیر وابسته تحقیق نداشتند (P>.05). این نشان می‌دهد که خانوارهای شهر تهران علی‌رغم احساس خطر زلزله، این خطر را تاکنون جدی نگرفته‌‌اند و اقدام عملی مؤثری در این زمینه انجام نداده‌اند. همچنین نتایج حاصل از روش تحلیل مسیر بر روی متغیر وابسته قصد انجام رفتارهای کاهش ریسک در آینده نشان داد چهار متغیر ادراک ریسک، کنترل‌پذیری، میزان اعتماد به مدیریت بحران شهری و طول مدت اقامت در شهر تهران با قصد و نیت رفتارهای کاهش ریسک تأثیر مستقیم داشته‌اند. در میان این متغیرها، تنها تأثیر ادراک ریسک به‌صورت مثبت بود. هم‌چنین در بررسی اثرات غیرمستقیم از طریق متغیر میانه ادراک ریسک، سه متغیر سن، خودکارآمدی، نیاز به محافظت به‌صورت مثبت و تعصبات خوش‌بینانه و درآمد از طریق تأثیر بر روی متغیر میانه ادراک ریسک به‌صورت غیرمستقیم بر روی قصد و نیت رفتارهای کاهش ریسک تأثیرگذارند.}, keywords_fa = {ادراک ریسک,رفتارهای تعدیل‌کننده ریسک,زلزله شهر تهران,روش تحلیل مسیر}, url = {https://geoeh.um.ac.ir/article_28846.html}, eprint = {https://geoeh.um.ac.ir/article_28846_b1aa419acada84ad280c26e161f7fc26.pdf} } @article { author = {Hajinejad, Ali and Anabestani, Aliakbar and Noruzi, Malihe and Khatami, SayedehSomayeh}, title = {Satisfaction Evaluation of the Quality of Life in Biological Complexes after an Earthquake Event Case Study: Zirkooh (Ghaen))}, journal = {Journal of Geography and Environmental Hazards}, volume = {4}, number = {3}, pages = {61-74}, year = {2015}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v4i3.44120}, abstract = {1. Introduction Earthquake is a significant natural disaster which always affects different areas. Zirkooh city due to the existence of active faults always faces destructive earthquakes (Rajabi, 1384, p. 279). In May 9, 1997 this city was stricken by a severe earthquake with an intensity of 1.7 Richter scale, and faced severe physical injuries, financial, and social damages. Following the earthquake, Islamic Republic Housing Foundation of Southern Khorasan province which is in charge of the construction of villages hit by natural disasters, adopted aggregation and integration policies. Because of the need to address in timely manner to the damaged villages has caused to pay less attention to some factors such as economic, social-cultural, and skeletal and also village residence satisfaction of their life quality in biological complexes which this leads to negative consequences. In this regard, the survey was conducted in response to the main question that is, “Is accommodation of the villagers of earthquake-stricken villages in rural biological complexes could answer their satisfaction of life quality compared to their life condition before earthquake?” 2. Study Area Zirkooh city is located in the northeast of southern Khorasan with its central city named HajiAbad It is bordering RAZAVI KHORASAN from the north and from the south is bordering DARMIAN city. From the west, it is bordering QAEEN city , and also is bordered by Afghanistan from east side. Totally, this city has 138 towns that among them 103 towns have residents and 35 are haunted towns. (South KhorasanPlanning Department, 1393). The study area of this research is villages' damaged areas by the earthquake of May 9, 1997 that these areas have been resettled in four complexes named, BARENJAN, HAJI ABAD, GAMANJ and MEHMANSHAHR. 3. Matarial and Methods This study is practical in term of purpose and analyticalin term of method. The statistical population is integrated rural areas by earthquake of May 1997 that are resettled in four complexes (BARENJAN, HAJI ABAD, GAMANJ, and MEHMANSHAHR). Among them 227 households were chosen by Cochran method. To analyze the data, descriptive statistics (central index and dispersion) and and Wilcoxon non-parametric and t parametric of dependent samples are used. 4. Results and Discussion Analyzing the results of the Wilcoxon test indicated that the rate of economic satisfaction of rural residents compare to previous settlement is not significantly different. Reviewing acquired data of dependant two-sample t test totally, is an indication of increasing the satisfaction rate of cultural-social in all complexes. Analyzing the findings of dependant two-sample t test overall, showed that the rate of villagers’ spatial-physical satisfaction after the earthquake and their accommodation in biological complexes compared to their condition before the earthquake in all complexes has increased. Overall employment quality, income, education, attendance, social and environmental cohesion, in all complexes was in a low rate. Surveying residents’ view based on Likert, indicated that the majority of the respondents are satisfied with their life quality in these biological complexes. 5. Conclusion In this study, satisfaction of life quality in biological complexes was checked using the collected data of questionnaires in Zirkooh city. To check the findings of this study, it can be deduced that aggregation and integration of sample villages lead to improved spatial-physical and socio-cultural quality and hence villagers’ satisfaction In contrast the role of economic quality of complexes in resident satisfaction in rural areas was in low rate. In study complexes due to lack of attention to the occupation productivity and inequality in job opportunities in one hand and water and soil resources constrain on the other hand, made placed residents reuse their previous resources locating in previous areas. And this fact increased the distance between living place and working place so that villagers have to spend more time for transportation. Taken together, these factors have reduced the level of labor productivity and have increased costs and expenses.}, keywords = {Earthquake,Rebuilding,Biological complex,Satisfaction,Zirkooh city}, title_fa = {سنجش رضایت‌مندی از کیفیت زندگی در مجتمع‌های زیستی احداث شده پس از رویداد زلزله مطالعه موردی: شهرستان زیرکوه (قاین)}, abstract_fa = {یکی از مهم ترین مسائل برنامه ریزان روستایی کشور، وقوع سوانح طبیعی در مناطق روستایی با توجه به آسیب پذیری بسیار بالای این مناطق است. گاهی حوادث طبیعی خود به‌تنهایی یک بحران محسوب نمی شود، بلکه بحران زمانی رخ می دهد که جامعه ای در محلی ساکن شوند که برنامه ریزان بدون توجه به علایق و خواسته های آنان، در نظر گرفته اند؛ بنابراین ارزیابی شاخص کیفیت زندگی در نواحی روستایی آسیب دیده ای که طرح تجمیع برای آن‌ها اجرا شده ‌است، دارای اهمیت است. هدف پژوهش حاضر آن است که ارزیابی نقش مجتمع‌های زیستی روستایی بنا شده پس از رویداد زلزله در بهبود کیفیت زندگی مردم در مقایسه با قبل از زلزله را با استفاده از شاخص های ذهنی کیفیت زندگی مورد تحلیل قرار دهد. تحقیق از لحاظ هدف کاربردی و از لحاظ روش توصیفی– تحلیلی است. داده‌های مورد نیاز از مطالعات کتابخانه‌ای و پیمایشی گردآوری شده است. جامعه آماری نواحی روستایی ادغام شده بعد از رویداد زلزله اردیبهشت 1376 است که در چهار مجتمع بارنجگان، حاجی آباد، گمنج و مهمانشهر اسکان داده شدند که از این میان 227 خانوار به روش کوکران انتخاب شده است. به‌منظور سنجش تحقیق با آزمون T و ویلکاکسون، با بهره‌گیری از نرم افزار SPSS بوده است. نتایج پژوهش حاضر نشان می دهد تجمیع روستاها توانسته بهبود چشمگیری در کیفیت زندگی ساکنان روستایی ایجاد کند. در چهار مجتمع مورد مطالعه به‌جز در شاخص درآمد و ثروت در 9 شاخص دیگر روند مثبتی مشاهده می شود که این به دلیل عدم توجه به امر اشتغال زایی و نابرابری در بهره مندی از فرصت های شغلی از یک جهت و محدودیت منابع آب‌وخاک از سوی دیگر است.}, keywords_fa = {زلزله,بازسازی,مجتمع زیستی,رضایت مندی,شهرستان زیرکوه}, url = {https://geoeh.um.ac.ir/article_28856.html}, eprint = {https://geoeh.um.ac.ir/article_28856_f309703768dc5a5213fa29956160b085.pdf} } @article { author = {Parak, Fatemeh and Roshani, Ahmad and Alijani, Bohlol}, title = {Synoptic Investigation of the Role of the Sudanese Low Pressure System during Wet and Drought Years in the Southern Half of Iran}, journal = {Journal of Geography and Environmental Hazards}, volume = {4}, number = {3}, pages = {75-90}, year = {2015}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v4i3.40062}, abstract = {1. Introduction Variability and changes in precipitation amounts, including extreme precipitation and droughts, trigger relevant societal and environmental impacts. Atmospheric circulation strongly determines precipitation variability over southern half of Iran. The influence of prevalent synoptic situations on the distribution of precipitation amounts needs to be understood, as well as their frequency changes to appraise the impact of atmospheric circulation on intra- and inter-annual (decadal) fluctuations of precipitation amounts. On the other hand, the atmospheric moisture budget plays important role in the hydrology of this region. The aridity in the southwest and south of Iran is due to subsidence scale caused by Hadley circulation and a location far from oceanic sources of moisture. However the moisture and other properties of atmospheric quantities are transferred by local circulation from another source to the given region. Many investigations have been carried out on this subject. The consideration of the precipitation and its source region of moisture flux over south and southwest of Iran, during 1970-74 has been shown that 23 percent of the total low pressure system which passed over this area are from the southwest of the Red Sea (Faraji, 1982). In the investigation of moisture flux over Iran, which is carried out by Alijani (1995) noted that the Mediterranean Sea is the main source of moisture for precipitation over Iran. Evans, Smith & Oglesby (2004) have shown that the Persian Golf and the Caspian Sea are the main sources of moisture for precipitation over the Alborz and the Zagros mountains. They have shown that the subtropical jet current brings the warm and moist air from the South part of Saudi Arabia and the Aden golf to the Middle East in the middle and higher troposphere (Dayan &Abramski, 1983). The Red sea inverted trough at the surface with regard to its amplitude, is the Major source that transfer warm and moist air from the Aden golf to the East and North of the Arabian peninsula and also southwest and south of Iran (Alpert, 2001). The low pressure system which is formed at southwest of the Red sea is associated with high potential acceptability of moisture and warm air due to its characteristics of dynamical and thermo dynamical pressure for heavy rainfall over the study area. Rurerde (2006) using specific humidity map and its extension from the Caspian Sea to the North part of Iran derived a value of moisture quantities from each source region of moisture to the precipitation over Iran. The principal objective of this research was to understand the characteristics of moisture flux from each region of moisture source and their contribution to the rainfall during the above period. 2. Study Area The study area for this study is southern half of Iran, which lies approximately between 25N and 35N in latitude and between 44_E and 64_E in longitude. The study area of this research contains some provinces such as: Ilam, Khozestan, Lorestan, CharmahalBakhtiyari, Kohkiloye and Boyerahmad, Bushehr, Esfehan, Yazd, Kerman, Hormozgan, Fars, and Khorasan Jonobi. Based on the Koppen climate classification, most parts of this area are categorized as generally having arid (BW) and semi-arid (BS) climates. The important mountain of this area is the Zagros, which play an important role in nonuniform spatial and temporal distribution of precipitation. 3. Material and Methods Examination of precipitation properties needs long and high quality records of data. In the present study, the time series of precipitation data at 183 stations for the period 1974-2004 were collected from the Islamic Republic of Iran meteorological organization (IRIMO) and were analyzed. Data homogeneity is assessed by IRIMO previously. The Empirical orthogonal function (EOF) was applied to detect and describe spatial and temporal change in the precipitation. In addition, the principal component (PC) was applied to detect dry and wet years. In addition, to identify the spatial and temporal variations of the precipitation, we used the NCEP-NCAR reanalysis monthly mean values of the temperature, Geopotential height and pressure in 1000, 850, 500 and 300 hPa levels. These data have been widely used by many researchers over the last few years in tropical climate research. Finally, we calculated 30 years anomaly for these levels in dry and wet years. 4. Results and Discussion The maps of the wettest months have shown the synoptic situation over study and its adjacent area during the above period. These figures have show the high pressure over the Oman and the Arabian seas, deep trough over the East of the Mediterranean and the west of the Red sea. In this case, eastern Saudi Arabia received more moisture and latent heat fluxes than the other parts of the area. Two moisture source regions as observed from the divergent flux, which are located over the Aden golf and Red sea, supply moisture to study region. Southern half of Iran receives precipitation during this study, mainly from the west of the Indian Ocean (the Arabian Sea, the Oman Sea, The Aden golf), the Red sea and the some extent from the Mediterranean. The divergent moisture and latent heat flux during wet cases were observed over north part of the Arabian Sea, the Aden golf, the central part of the Red sea and convergence was observed over South, central of the Arabian Peninsula, southern half of Iran. These processes are indicative of the upward motion of moist air, which in turn may release latent heat due to condensation. This available heat energy may be the source of low-level latent heat instability. The large amount of moisture and latent heat flux over Saudi Arabia in is transported, by rotational wind from the Red sea and the Mediterranean as mentioned above. Conversely, in dry years due to weak trough of East Mediterranean, systems move from latitudes upper than 40ºN and the cold air does not transfer from the southeast Europe to the Northeast of Africa resulting development of Sudan low. Overall, decreasing transfer of cold air will lead to decreasing of moisture and latent heat flux from the Indian Ocean to the southern half of Iran. 5. Conclusion Atmospheric circulation strongly modulates precipitation patterns. Precipitation is one of the most important atmospheric variables in the global hydrological cycle and plays a key role in the Earth’s energy balance.The investigation of synoptic maps in 1000, 850 and 500 hPa levels in four systems shows that in wet years due to deep trough of East Mediterranean and West of the Red Sea, the cold air transfers from the southeast Europe to the Northeast of Africa resulting development of Sudan low. This low transfer to the center and north of the Arabian Peninsula, then move to the Southern half of Iran. The development of this low is due to release of sensible heat from the Arabian Desert and latent heat flux which transfer from the Indian Ocean, to this area. This low affects the southern half of Iran with significant value of perceptible water and low- level latent instability. It is seen that the transfer of moisture flux in the low-layer from the Indian Ocean plays an important role in precipitation over study region. Conversely, in dry years due to weak trough of the East Mesiterranean, systems move from latitudes upper than 40ºN and the cold air does not transfer from the southeast Europe to the Northeast of Africa resulting development of Sudan low. Overall, decreasing transfer of cold air will lead to decreasing of moisture and latent heat flux from the Indian Ocean to the southern half of Iran. The findings of this study confirmed the results of the previous studies (Alijani, 1995; Farajzadeh, 2007;Milind, 2006; Mofidi&Zarin, 2005).}, keywords = {Synoptic investigation,Sudanilow pressure,Wet and drought years,Southern half of Iran}, title_fa = {واکاوی همدیدی سامانه کم فشار سودانی در رخداد ترسالی ها و خشکسالی های نیمه جنوبی ایران}, abstract_fa = {مطالعه انجام شده در این پژوهش نشان می دهد سامانه های سودانی در ترسالی و خشک‌سالی نیمه جنوبی ایران نقش مهمی را ایفا می کند. بررسی نابهنجاری گرته های همدیدی در ماه‌های خشک و تر نشان گر دو گرته متفاوت حاکم در منطقه است. در گرته ترسالی، شرق مدیترانه، غرب دریای سرخ، نیمه غربی شبه‌جزیره عربستان، جنوب و جنوب غرب ایران، شمال دریای خزر همراه با نابهنجاری های منفی فشار و ارتفاع در سطح زمین و در تمام لایه-های وردسپهر است، که نشان گر عمیق بودن ناوه شرق مدیترانه و دینامیکی بودن سامانه های کم فشار سودانی است. همچنین بر روی شمال شرق و شرق عربستان نابهنجاری های مثبت فشار و ارتفاع در سطح زمین و لایه های زیرین و میانی وردسپهر حاکم است که هوای گرم و مرطوب نواحی غرب اقیانوس هند را به درون سامانه سودانی تغذیه می کند. حرکت شرق سوی سامانه سودانی سبب انتقال حجم وسیعی از شار رطوبت و شار گرمای نهان به نواحی جنوب و جنوب غرب ایران می‌شود که منجر به ریزش بارش های هم رفتی بسیار بالایی به میزان چهار برابر میانگین سالانه در جنوب و جنوب غرب ایران شده است. در سال‌های خشک نابهنجاری های دما و ارتفاع متفاوت با دوره ترسالی است؛ بدین معنی که نواحی شرق دریای مدیترانه، سراسر غرب دریای سرخ، نیمه غربی شبه‌جزیره عربستان، نواحی جنوبی ایران و بر روی سواحل جنوبی دریای خزر نابهنجاری های مثبت در سطح زمین و در کلیه ترازهای وردسپهر دیده می شود. علاوه بر این، نواحی شمال شرقی و شرق شبه‌جزیره عربستان از نابهنجاری های منفی و یا نابهنجاری های مثبت بسیار کم برخوردار است و نشان می دهد که سامانه سودانی چندان فعال نبوده و رطوبت به نحو شایسته ای از نواحی غرب اقیانوس هند به درون سامانه سودانی انتقال نمی یابد.}, keywords_fa = {واکاوی همدیدی,کم فشار سودانی,خشک‌سالی و ترسالی,نیمه جنوبی ایران}, url = {https://geoeh.um.ac.ir/article_28896.html}, eprint = {https://geoeh.um.ac.ir/article_28896_e211f5dcdc841eca13c17a113ae69f70.pdf} } @article { author = {Nazaripour, Hamid}, title = {Development of a New Comprehensive Multivariate Aggregate Drought Index (ADI) based on Principal Component Analysis (PCA) for Hydro- Meteorological Droughts Assessment in the Southeast of Iran (Case Study: Pishin Dam Basin)}, journal = {Journal of Geography and Environmental Hazards}, volume = {4}, number = {3}, pages = {91-112}, year = {2015}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v4i3.31626}, abstract = {1. Introduction A drought is a prolonged period of water deficit and usually occurs when an area does not receive significant precipitation for a sustained period of time, say several months (Chen, Kuo, & Yu, 2009; Linsely, Kohlerm, & Paulhus, 1959). The effects of drought often accumulate slowly over a considerable period of time that may linger for several years even after the termination of drought. Therefore, some authors have called it a creeping phenomenon (Wilhite, 2000). It is difficult to precisely determine the onset and end of a drought event. A drought can be short, lasting for a just a few months, or it may persist for years before climatic conditions return to normal. Drought considered as the most complex, but the least understandable phenomenon of all the natural hazards affecting more people than any other hazards (Mishra & Desai, 2005). Droughts can be classified into four categories as meteorological, hydrological, agricultural and socio-economic (American Meteorological Society, 1997; Palmer, 1965; White & Walcott, 2009). The preparedness and planning for a drought depend on the information about its areal extent, severity and duration (Mishra & Singh, 2011). This information can be obtained through drought monitoring that is usually done with the use of drought indices (DIs) which provide information to decision makers about drought characteristics. Thus, these indices can be used to initiate drought action plans. Prediction of droughts is useful for early warning that may reduce the response time and consequently the impact of a drought. For many regions, especially semi-arid regions, limited knowledge is available about the diurnal and seasonal cycles of land surface interactions. Semi-arid areas pose a challenge due to large contrasts between dry and wet conditions within a temporal cycle (Schuttemeyer, 2005). Meteorological drought is generally an indicator of other drought types with below normal precipitation, and usually occurs first before other drought types do. The seasonality and climatological conditions vary by location. Drought severity may differ from site to site under different climatic conditions, hence, as many as applications of DIs and their comparisons are beneficial for specific regions in the world. The objective of this study is to develop an aggregate drought index (ADI) based on principal component analysis (PCA) to assess the severity of Hydro-Meteorological drought in the southeast of Iran. Therefore, Stream flow drought index (SDI) and effective drought index (EDI) is determined for several different monthly time steps. The ADI is calculated after a principal component analysis to determine aggregated index value. 2. Study Area Southeast area of Iran is confined to Sistan and Baluchestan province and located southeast of the intersection of between 29ºN and 57ºE. In this area, precipitation mostly falls in winter and summer seasons. Summer rainfall related to the monsoon mass effect, which comes from Indian Ocean. Climate is arid and semi-arid. Bahouklat is the most important river in area. The origin of this river is the Pir Abad Mountains in the southeastern of Iranshahr city and the passing of Sarbaz, Bahoukalat, Pishin and Dashtyari regions eventually lead to Govare Bay. This river has various names in different regions and called Sarbaz River from Sarbaz to Rask and passes of Pishin dam. Discharge of this river (Sarbaz) is very important in this area. 3. Material and Methods Hydrological and meteorological drought values are necessary for ADI computation over a long period. Therefore, streamflow drought (SDI) and effective drought (EDI) Indicators were used to estimate the hydrological and meteorological droughts. The input variables include the daily values of stream flow of Sarbaz River in the Pirdan hydrometric station and rainfall during the 21 March 1985 to 20 March 2011 common period. Variables were arranged according to water year (also water year, flow year or discharge year), which begins in October in Iran. Daily timestep of SDI and EDI were estimated respectively according to Nalbantis (2008) and Byun and Wilhite (1999) and then ADI were calculated based on principal component analysis according to Keyantash and Dracup (2004). 4. Results and Discussion Drought is a very common phenomenon in Iran and particularly in the south east and it has become a recurrent phenomenon in this area in the last few decades .The hydro-meteorological drought index was applied for the identification of drought severity in south east of Iran and drought occurrences were monitored during the experimental years of 1985/86 to 2010/11. Results based on the aggregate drought index (ADI) revealed that a long period of hydro-meteorological drought occurred from 1994/95 to 1998/99. Also, a prolonged wet period has started immediately after the end of drought and has continued to June 2005. In addition, according to drought severity, 1997/98 and 2003/04 water years respectively are extreme drought and extreme wet years. Finally, we have compared the performance of EDI (Meteorological drought index) and SDI (Hydrological drought index) with aggregate drought index. Based on this comparison, aggregate drought index (ADI) could be better highlighting the drought conditions and its characteristics. 5. Conclusion Aggregate drought index (ADI) is methodology presented for replacing the uni-dimensional analysis of drought phenomena which can assist authorities and stakeholders to take rational decisions for combating droughts. Using this approach, a more effective way for assessing the severity of drought is obtained. On the other hand, ADI shows capability to detect dry and wet years. Moreover, it has capability to detect historical drought. Overall, by considering the results, the ADI is more reliable than EDI and SDI for drought monitoring in the study area. In this study, ADI time series were compared against the EDI and SDI to describe an important and long drought event in south east of Iran, the 2003-2004 event from a hydro-meteorological perspective. The ADI methodology provides a clear, objective approach for describing the intensity of drought and can be readily adapted to characterize drought on each area.}, keywords = {Hydro-meteorological drought,Aggregate Drought Index,Principal component analysis,Pishin Dam Basin,Southeast of Iran}, title_fa = {توسعه یک شاخص ترکیبی چندمتغیره بر پایه تحلیل مؤلفه مبنا برای ارزیابی خشک‌سالی‌های آب – هواشناختی در جنوب‌شرق ایران (مطالعه موردی: حوضه سد پیشین)}, abstract_fa = {خشک‌سالی یک ناهنجاری‌ اقلیمی‌ است که با کمبود (نبود) بارش و مُهیایی منابع‌ آب در پهنه‌ جغرافیایی بزرگ پیوند داشته و در طول دوره‌ قابل‌توجهی از زمان گسترش می‌یابد که می‌تواند بخش‌های مختلف از زندگی و محیط‌زیست را متأثر سازد. نمایه‌های زیادی برای پایش شرایط خشک‌سالی توسعه یافته‌اند. گسترش فضایی، زمانی و شدت (سختی) خشک‌سالی با استفاده از این شاخص‌ها مشخص می‌گردد. در این بررسی، یک شاخص ترکیبی برای ارزیابی خشک‌سالی‌های تلفیقی (آب- هواشناختی) در جنوب‌شرق ایران توسعه داده شده است. شاخص ترکیبی به‌طور جامع همه اشکال فیزیکی خشک‌سالی (هواشناختی، آب‌شناختی و کشاورزی) را از طریق انتخاب متغیرهای مرتبط به هر نوع خشک‌سالی شامل می‌شود. در این بررسی، ارزش‌های روزانه شاخص خشک‌سالی مؤثر و شاخص خشک‌سالی جریان رودخانه‌ای تحت یک تحلیل مؤلفه مبنا قرارگرفته و بر اساس مؤلفه نخست آن، ارزش شاخص ترکیبی واحد به دست آمده‌ است. دوره مورد بررسی از سال آبی 61-1360 تا 90- 1389 شمسی و سرآغاز سال‌ آبی نیز از ماه مهر تعیین گردیده است. بر اساس نتایج شاخص ترکیبی، یک دوره بزرگ خشک‌سالی از سال آبی 79-1378 الی 85-1384 در جنوب‌شرق ایران حاکم بوده است که شدت آن در سال آبی 83-1382 فوق‌العاده زیاد بوده است. توزیع فضایی بارش ایران در این هنگام نیز آشکار می‌سازد که در فصل‌های پاییز و زمستان مقدار دریافتی بارش در منطقه جنوب‌شرق ایران بسیار ناچیز بوده است. روش‌شناسی شاخص ترکیبی خشک‌سالی، یک رویکرد عینی و واضح برای توصیف شدت خشک‌سالی‌های تلفیقی فراهم‌ می‌کند. شاخص مزبور به‌خوبی قادر به نمایش رفتار خشک‌سالی‌های آب- هواشناختی محدوده مورد مطالعه بوده و به‌عنوان شاخص ترکیبی جدید برای پایش و ارزیابی خشک‌سالی منطقه‌ای توصیه می‌گردد.}, keywords_fa = {خشک‌سالی ‌آب- هواشناختی,شاخص ترکیبی خشک‌سالی,تحلیل مؤلفه مبنا,حوضه سد پیشین,جنوب‌شرق ایران}, url = {https://geoeh.um.ac.ir/article_28941.html}, eprint = {https://geoeh.um.ac.ir/article_28941_c621921b1b8d71a1137a70a3f1383131.pdf} } @article { author = {Ramesht, Mohammad Hossein and Entezary, Mozhgan and Delsooz, Susan}, title = {Towards Improving the SLEMSA Model using the Statistical Method of Assigning Erosion Factors}, journal = {Journal of Geography and Environmental Hazards}, volume = {4}, number = {3}, pages = {113-126}, year = {2015}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v4i3.39791}, abstract = {1. Introduction SLEMSA is one of the erosion estimate models presented by Stocking (1978). On one hand, this model has accurate ability y of assessing the erosion rate due to application of non-linear relation evaluating methods. On the other hand, the model benefits from the application of actual deductible numbers in calculation, and its educational approaches. The main question raised in relation to this model is that whether we can add a new capability to this model which can enable us to show us the portion of each element in the erosion. To respond this question, the drainage basin was chosen and we proceeded to calculate the erosion factors rate in SLEMSA model in 214 cells (4km2) and then through the use of vectorial dimensionless method, the main volumes of the model including X, K, C elements were made dimensionless and then the portion of each factor in each cell was calculated by Logarithmic Revers method. 2. Study Area The Gulpayegan drainage basin at the west of Esfahan Province is located in the area of 1045 cubic kilometers; the geographical longitude coordinate is chosen 50 degrees and 2 minutes to 50 degrees and 18 degrees E and the geographical latitude is 33 degrees to 33 degrees and 33 minutes N. From the north it leads to Khomein, from the south to Khunsar and Freidan, from the east to Meymeh and Esfahan, and from the west it leads to Aligudarz. 3. Material and Methods The numerical data of Gulpayegan drainage basin is obtained from DEMIran (90m).Then, these data were divided to 214 cells (each cell 4 Km2) and cultivated the rate of X, K, C (these are the main factors in SLEMSA model) for each cell. By using the Kreging technique, mapping of erosion estimate was made possible in this way. In the second phase, , the portion of each erosion factor (X, K, C) for each cell is calculated, using the vectorial dimensionless and the Logarithmic Revers methods. The Logarithmic Revers method clearly showed that it is possible to determine each factor portion, specify the factor having more effectiveness in each pixel unit, and then to proceed to draw the region erosion map based on the premier factor. 4. Results and Discussion SLEMSA model has special framework within which Stocking (1978) first introduced the erosion factors, then developed it, defined, and determined the scale and method of quantitative evaluation technique for each of the factors with non-linear relations, combination, and minimization. Z = K.C.X formula According to the SLEMSA model framework, three topographic factors (x), erosion and soil corrosion capability (K) and the agricultural management factor (C) were calculated for each of pixels and the soil erosion rate which has been lost in ton/hectare/year was calculated annually based on the z=k.c.x equation for the region under study and the obtained results were changed into the erosion rate map in the surfer program through the use of the Kreging technique in SLEMSA model. The dimensionless operation on obtained data known as the statistical technique in this article is considered as the basis and essence of the argument developed in Stocking model. After identifying the dimensionless erosion numbers of each pixel, the condition for providing each element portion in the SLEMSA model is obtained. In order to prepare each portion, it is sufficient to take logarithm from both sides of equation to be able to identify the portion of each element in whole evaluation. (2) Zs = Xe.Ke.Ce Therefore, the condition for calculating the effect rate for each of the model factors is obtained in this phase by taking logarithm from both sides of equation 3 . (3) LogZs = logXe +logKe +LogCe In the end, the portion rate for each factor is obtained for the whole Z volume.Following the identification of the premier factor in each pixel, we can proceed to separate and clarify them through some specified colors. 5. Conclusion As we observed, the evaluation of the rates of this model could show the erosion point differences but it is never capable of analyzing the effective factors in estimate although this method has important values and the map results cannot be overlooked. By using this improved technique, the ability of SLEMSA method is upgraded. The results of this study showed that: 1- By performing the statistical dimensionless technique in SLEMSA model, the triple-factor portion of erosion is identified. 2- By using this method, we can achieve the regions priority area for fulfilling the erosion control plans, as this priority is based on the premier factor portion in evaluation and erosion estimate. 3- By assigning the portion of erosion factors in this model, we can determine the techniques against erosion in different regions and avoid using just one method for its control.}, keywords = {Erosion,Gulpayegan,SLEMSA model,Vectorial dimensionless}, title_fa = {ارتقاء مدل اسلمسا با ترفندی تکنیکی در سهم گذاری عوامل فرسایشی}, abstract_fa = {اسلمسا یکی از مدل‌های تخمین فرسایشی است که توسط استوکینگ در سال 1978 ارائه شد. این مدل به خاطر بکارگیری روش‌های رابطه سنجی غیر خطی از توانمندی‌های دقیقی در برآورد میزان فرسایش از یکسو و بکارگیری اعداد کسر پذیر واقعی در محاسبه برخوردار و از دیدگاه آموزشی دارای مزیت‌های فراوانی است. سؤال اساسی درباره این مدل آن است که آیا می‌توان با اعمال ترفندی تکنیکی قابلیت جدیدی به این مدل افزود تا سهم هریک از عوامل مؤثر در مدل را در هر نقطه به ما نشان دهد. این مسئله سبب شد تا در قالب یک طرح پژوهشی و با انتخاب حوضه آبریز گلپایگان و اجرای مدل مذکور، نسبت به محاسبه میزان عوامل فرسایش مدل اسلمسا در 214 سلول چهار کیلومتری اقدام و سپس با استفاده از روش بی بعد سازی برداری مقادیر اصلی در مدل، یعنی عناصر X,K,C بی مقیاس و آنگاه با واکاوی لگاریتمی سهم هریک از عوامل در هر سلول محاسبه گردد. این روش به‌خوبی نشان داد که می‌توان سهم هریک از عوامل را تعیین و عاملی که دارای تأثیرگذاری بیشتری است در هر واحد کاری (پیکسل) مشخص نمود و نقشه فرسایش منطقه بر مبنای عامل برتر را ترسیم کرد. نتایج حاصل از این تحقیق نشان داد که 1-با اعمال تکنیک بی بعد سازی آماری در مدل اسلمسا سهم عوامل سه گانه فرسایش را می‌توان مشخص کرد؛ 2- با اعمال این روش می‌توان به نقشه اولویت مناطق برای اجرای طرح‌های کنترل فرسایش دست یافت، به‌طوری‌که این اولویت بر اساس سهم عامل برتر در برآورد و تخمین فرسایش استوار شده باشد؛ 3-با سهم گذاری عوامل فرسایشی در مدل می‌توان تکنیک‌های مبارزه با فرسایش را در مناطق مختلف تعیین نمود و از یک روش یکسان برای مبارزه و کنترل آن پرهیز نمود.}, keywords_fa = {فرسایش,گلپایگان,مدل اسلمسا,بی بعد سازی برداری}, url = {https://geoeh.um.ac.ir/article_28978.html}, eprint = {https://geoeh.um.ac.ir/article_28978_fff896c782b0ce3d98f97f3e2cb2f9ec.pdf} } @article { author = {Taheri Saffar, Marjan and Shanoushi, Naser and Abolhassani, leili}, title = {Environmental, Social and Economic Impacts of Dam Construction in Khorasan Razavi Province (Case Study of Bar Dam in Neyshabur)}, journal = {Journal of Geography and Environmental Hazards}, volume = {4}, number = {3}, pages = {127-146}, year = {2015}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v4i3.45355}, abstract = {1. Introduction Any development with any quantity or quality degree has particular environmental impacts. Human manipulation in natural environment does not necessarily mean making changes in initial environment. Continuity of human action in the changing natural conditions, which could eventually disrupt the balance of existing environment or causes unintended and unforeseen consequences as currently human societies have been facing this problem. Obviously once the idea of construction comes until the project operation, a long and tough way must be passed over. Environmental considerations in all phases of the project are major issues that must be considered. This includes the entire process including design, implementation and even scheme exploitation. If human reactions and environmental interactions are assessed in the form of construction projects practices, environmental power and its potential will be revealed by initial recognition. Importance and dimensions of negative effects can be achieved by using modern methods. Based on the findings, rules can be implemented to reduce the adverse effects and to manage the negative effects. In recent decades, many countries, including Iran, in order to reduce problems caused by dehydration and to prevent crisis put a massive investment in water sector. Unfortunately, evaluations and studies conducted in the past decade on the physical structure based on rivers and nation and international level approve existing issues and problems in all dimensions, particularly sea water resources management or dam's water and modern water distribution networks. In this regard, the projects implemented and proposals examination using preliminary studies as documentary confirms the difficulties existence in economical, ecological, and especially social-management dimensions. In some of these projects lack of expected goals achievement including improving beneficiaries social and economic conditions, the relative balance between supply and demand for water resources or agricultural prospered are effective and have caused negative reactions among beneficiaries. Present study tries to examine impacts resulted by huge investments (physical structures) in constructing Bar-dam located in Neyshabur. Therefore, social, economic and environmental (ecological) dimensions at the basin level of Neyshabur bar dam in Khorasan Razavi were considered. Since economic self-sufficiency has a particular importance, and given that the crisis of water and dehydration is one of the major and basic public concerns, water storage and flood water flow control are of cases that involved water engineers and experts. Therefore, increase in water supply and flood and water flow control through the dam construction are always recognized the fundamental measures. 2. Study Area One of the main objectives of bar dam construction is supplying part of the required drinking water of Neyshabur County. The special concentration on the Neyshabur is because the county is special in culture and geopolitical position. In addition, increasing rural migration to the cities and also due to the development of the town, surrounding villages are connected to Neyshabur and are using urban water distribution network and other utilities raise more concerns on the county. The sum of these factors has led county to water shortage, especially in the summer. Due to the need for water supply to Firoozeh (Bozghan) and Neyshabur cities and also industrial needs of Khorasan steel complex and etc., bar dam construction and related facilities to meet these needs and optimal use of existing potential, regional water resources have been considered as a national and regional policies. This study attempts to answer the issues and questions for the Bar-dam. The research method in this study will be descriptive – analytical. Due to recent defects of available documents statistics, collecting data and required information will be carried out as documentary. Required Information of Bar dam environmental impacts assessment project is extracted. 3. Material and Methods Regarding impact assessment of development projects implementation, several methods and procedures have been devised and used that considering intended purposes, have different structures. To assess bar dam environmental impact, a Leopold two-dimensional matrix is used which in one dimension, environment various options comes that will be affected and in other dimension, different steps and phases of project (construction and operation) are discussed. The virtues of this matrix are summarizing both positive and negative impacts of the project. At this matrix first activity cases, environmental factors have been identified and the severity (impact amplitude) and the importance (magnitude) of intended effects are considered. This matrix includes 100 small activities on the horizontal axis (columns) and 88 environmental factors on the vertical axis (rows) that results in the formation of 8800 houses matrix or tables which every home or cell is a merge level of activity from horizontal axis and a parameter from vertical axis. After listing sub activities and factors, when there is a possibility that one activity has an impact on environmental factor the diagonal line is drawn on soluble cell diameter as they cross over, then in each cell two numbers are considered that one of them is domain or impact intensity and other is importance or impact magnitude. Impact importance criteria or domain are usually valuated by ±1 to ±5. At this method mark 5 very high and important positive impacts and mark 1 for a very low and insignificant partial effect is considered. Also grade -5 for an excessive negative effect and grade -1 for a very low negative effect is considered. Then these numbers sums and the sum of the numbers corresponding to each column represent the activity impact on all the assessed environmental factors. Finally, for each environment (physical, economic, social, cultural and biological) and for each construction phase and operation of the various options, a number is obtained, which leads to the best option. Assessing various impacts resulting from implementing the building of engineering constructions divided to construction phase and the phase of applying in physical, biological, socio-economic, and cultural environments in two cases of performing and failure to perform, in stages of preparing, constructing and applying, will be carried out. 4. Results and Discussion Matrix generated in this study consists of 44 columns and includes factors related to the implementation and operation phases and 58 rows includes physical, biological, socio-economic and cultural factors. After the final evaluation matrix Dam Project for two options, performing and failure to perform will be carried out. At the option seeking studies in order to determine the location of bar dam and other proposed structures in this plan several options have been considered which finally options by authorities in terms of technical and economic will be reconsidered and only one option as a best will be chosen. Therefore in bar dam environmental assessment only one option as a premier option is chosen. Therefore, in bar dam environmental assessment and related constructions, only one option is considered so performing option or failure to implement the plan is reviewed. Zero option or option Failure to implement the plan means that if dam has not been constructing in the region and the area has been abandoned, causes which environmental impact? However, for evaluating the effects of this option we should not imagine that this option will not have any deleterious effects on the region, because in some cases the lack of an implementation plan can cause a non-rectification impact in the region. Option A or option implements the plan at the current location in two constructions and operation phases is considered and the positive and negative effects of each phase have been determined. What is certain is that if implement or not implement the plan, there will be positive and negative impact on environment, but the important issue is making decision about implement or not to implement the plan. For making decision in this case, we should compare total impacts in two options of implement or failure to implement. In order to make the right decision on this issue the Leopold matrix in order to evaluate dam's construction impact on environment is used. Assessment of environmental impacts caused by dam projects in Neyshabur, Khorasan Razavi separately construction phase and operation in the physical, biological, socio-economic and cultural environments in implementing option and failure to implement option was carried out. The impact separated result shows that the total number project impact in preparation and construction phase was 398 cases, which 117 cases means 30% positive and 281 cases means 70% was negative that the main reason was different physical operation in the regional environment which often are short and required. In the exploitation phase, 123 of cases of environmental consequences was 71, means 61% positive and 49 cases means 39% was negative. Most of the adverse effects of the construction phase in implementing options are -263 which is related to physical environment and the greatest positive impact 729 is on the construction phase of implementing option on socio-economic environment. Also negative effect in operation phase is 253 and positive effect is 473, while dam's impoundment and also considering measures related to the evaporation of water from the reservoir water level can bring desirable environmental impacts for the region and in case of water recourses reliable management cause positive impact on socio-economic development of the region. Also results show that in exploitation phase more positive impact can be seen and this is more obvious particularly in socio-economic, cultural environment. Economic environment with 729 positive points on construction phase and 384 positive points on exploitation phase has the highest positive impacts of implementing the plan. 5. Conclusion Generally based on the environmental assessment performed on the bar dam project and its affiliated structures, total value of the project are 1219 points positive and 1179 points negative. The dominant aspect of the project outcomes, especially in exploitation phase is positive and in situations which consequences are negative, mostly consequences have weak and negligible destructive load which in terms of quantity can be reduced by authentic management and implementing environmental proposed measures especially implementing sand stabilization and forestry side projects in dam's construction area which can reduce project negative intensity impacts. Also, due to population growth and the increasing nutrient demands, unemployment and rural to urban migration, implementation has many positive results in employment status, income, migration, rural welfare and development of Khorasan Steel factory. So we can say that bar dam project implementation certainly has a lot of favorable impacts which trims adverse effects and creates large and significant benefits in the region. Therefore, the project is economically valuable and in order to achieve favorable objectives and keeping pace and directing with macroeconomic policy, applying an appropriate environmental management system, set activities to give direction to form the possible negative effects resulting from the implementation of such a huge project to a minimum is required.}, keywords = {Environmental impact,Leopold matrix,Bar dam,Neyshabur}, title_fa = {ارزیابی اثرات اقتصادی، اجتماعی و زیست‌محیطی احداث سد بار نیشابور}, abstract_fa = {هر نوع توسعه با هر درجه ای از کمیت یا کیفیت، آثار زیست محیطی ویژه ای را به دنبال دارد. دخل و تصرف انسان در محیط طبیعی لزوماً به معنی ایجاد تغییرات در شکل طبیعی و اولیه محیط است. تداوم عمل انسان در تغییر شرایط طبیعی، نهایتاً می تواند توازن های موجود محیط را برهم زده و زنجیره ای از پیامدهای ناخواسته یا پیش بینی نشده را دربرداشته باشد. طرح توسعه ای احداث سد نیز دارای اثرات مختلفی بر محیط فیزیکی، بیولوژیکی، اقتصادی-اجتماعی و فرهنگی می باشد. سد بار نیشابور، ازجمله سدهای احداث شده در استان خراسان رضوی است، که با هدف تأمین آب کشاورزی، تأمین آب شرب شهرهای نیشابور و فیروزه و کنترل سیلاب بر رودخانه بار احداث گردیده است. در این پژوهش سعی بر آن است اثرات ناشی از اجرای این طرح مورد ارزیابی قرار گیرد و دو گزینه عدم اجرا و اجرای طرح را با استفاده از ماتریس لئوپولد مورد سنجش قرار دهد. با بررسی ماتریس ارزیابی اثرات پروژه مورد مطالعه بر محیط‌زیست ، گزینه عدم اجرای پروژه درمجموع 48 امتیاز منفی کسب کرد. این در حالی است که گزینه اجرای پروژه با انجام اقدامات اصلاحی در طرح احداث و بهره‌برداری از سد مخزنی بار و سازه های وابسته به آن با کسب 151 امتیاز مثبت، گزینه برتر و نهایی معرفی گردید.}, keywords_fa = {اثرات زیست‌محیطی,ماتریس لئوپولد اصلاح شده,سد بار,نیشابور}, url = {https://geoeh.um.ac.ir/article_29010.html}, eprint = {https://geoeh.um.ac.ir/article_29010_d9487cda59351b77f6eacf28813e41c0.pdf} }