@article { author = {Khalaj, Mohammad}, title = {Seismic Hazard in Babolrud and Talar Basins based on Morphometric Indices}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {1-16}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v9i1.86384}, abstract = {Introduction Tectonic geomorphology is a knowledge that can determine the effect of active tectonic using the geomorphic indices as a quantitative description of the rivers form. Accordingly, quantitative measurements provide conditions that allow them to identify the status of active tectonics areas. Active tectonic processes can affect the shape and performance of rivers. The extraction of geomorphic indices using digital elevation map (DEM) in the GIS in the past two decades has been a fast and accurate method for drainage basin analysis so that these indices are used for quick evaluation of recent tectonic activities in a particular region. Base on a natural theory, rivers are the first environmental forms that show a relatively rapid response to changes in the bedding or changes in the outflow of the bed. Regarding the proved reactions of rivers to the occurrence of normal changes, it is possible to analyze them by using geomorphic indices as the result of the effects of tectonic on the river's route. Geomorphic indices are especially used for active tectonic studies. With the study of topographic landforms and the model of drainage systems using geomorphic indices and the geological structure of each area, it is possible to evaluate the active tectonic performance and to determine the absence of active tectonic movements. The quantitative measurements provide conditions that allow them to identify the status of active tectonics areas. Along with the advancement of tectonic science of geomorphology, scientists have found that active tectonic processes can affect the shape and function of rivers being one of the most important observations that occur rapidly. Consistently in respond to deformation caused by active tectonics at the surface reflecting minor changes in topography, thus examining drainage pattern and river diversion provides important information on structural expansion and evolution of the area. The study area is classified into four categories of very high, high, medium and low tectonic activities. Alborz mountain range is the result of two orogenic movements. One of them is Precambrian ores (Acinitic), the course of which is essentially a metamorphism that leads to the interconnection and hardening of the paving stones in the Precambrian, The second one is the Alpine orogeny movements that happens in Mesozoic and Cenozoic periods. This mountain range is approximately 600 kilometers long and 100 kilometers wide along the south side of the Caspian Sea. The northern margin of the Alborz line is usually sloping. General trend of study area is NE-SW.  Materials and Methods In this research, with using the Arc GIS software and 1:100000 Geological maps, at first, rivers and basins shapes of the area were extracted using STRAHLER method using 30 m accuracy digital elevation model in Arc GIS software. Then the necessary modifications to the wells and extraction basins were carried out using topographic maps and satellite images and finally a part of central Alborz at Talar and BabolRud area was divided into 19 catchments. 5 morphotectonic indices such as hierarchical anomalies (Δa), Bifurcation (R), Form factor (Ff), drainage density (Dd) and Relative relief (Bh) were calculated in drainage basins. Using the Relative Active Tectonic (IAT) index, the study area was classified into 4 categories. Category 1 indicates a very high tectonic activity. Category 2 is the high tectonic activity. Category 3 shows the average geological activity and category 4 activities are low relative construction. A tectonic activity zoning map was prepared for each indicator in the study area and the results of the indices were analyzed Results and Discussion Based on studies of hierarchical anomaly indices in sub-basins associated with North Alborz and Khatirkuh faults, this index increases and shows very high and high rates. Intersection between these faults and the sub-basins waterway has caused anomalies in the connection of low-grade waterways to several degrees higher. In sub-basins 11, 12, 13 and 14 which are dominated by the above-mentioned faults, the bifurcation index and the elevation changes are due to the activity of these faults are high. Conclusion Studies in this section of the Alborz mountain range using morphometric indices such as hierarchical anomalies (Δa), Bifurcation (R), Form factor (Ff), drainage density (Dd) and Relative relief (Bh) and using the IAT Index in this area, shows that recent tectonic activity is generally due to the faults activity in the region such as North Alborz and Khatirkuh faults are in a high and very high categories. Based on these studies, it was found that some other minor faults formed due to high tectonic activity and caused by major faults such as North Alborz, Khatirkuh and other major faults in the area affect the indices numbers. Tectonic impacts show that about 33.3% of the sub-basins associated with the major and minor faults}, keywords = {Alborz,Catchment,fault,Morphotectonic,river,Earthquake}, title_fa = {تحلیل مخاطرات لرزه ای حوضه آبریز تالار و بابل رود بر اساس ارزیابی شاخص های مورفوتکتونیک}, abstract_fa = {علمی که تأثیر تکتونیک فعال را با استفاده از شاخص­های ژئومورفیک به عنوان سنجش و توصیف کمّی اشکال و چشم­اندازهای زمین مشخص نماید، مورفوتکتونیک نامیده می­شود؛ اندازه­گیری­های کمی شرایطی را فراهم می­آورد تا با استفاده از آن­ها به شناسایی وضعیت مناطق دارای زمین­ساخت فعال پرداخته شود. در این مطالعه با استفاده از شاخص­های کمی ریخت­سنجی بخشی از البرز مرکزی که در محدوده حوضه­های آبریز تالار و بابل­رود قرار دارد مورد بررسی قرار گرفته است و 5 شاخص ناهنجاری سلسله مراتبی (∆a)، انشعابات (R)، شکل حوضه (Ff)، تراکم زهکشی (Dd) و برجستگی نسبی (Bh) در 15 حوضه زهکشی در محیط نرم­افزاری Arc GIS به منظور تعیین کمی میزان تکتونیک فعال این منطقه محاسبه شده است. نتایج به­دست آمده از محاسبه شاخص­های فوق بیان­گر آن­ است که در محل تقاطع گسل­های شمال البرز و خطیرکوه و هم­چنین گسل­هایی که در دامنه شمالی البرز در اثر فعالیت این گسل­های بزرگ شکل گرفته­اند مقادیر به­دست آمده از شاخص­های یادشده، بالا بوده که بیانگر وجود فعالیت­ تکتونیکی بالا و بسیار بالا در آن نواحی است. در اثر بالا بودن این مقادیر انتظار می­رود که ریسک لرزه­خیزی منطقه نیز در اثر گسیختگی گسل­ها افزایش یابد.}, keywords_fa = {ژئومورفولوژی,مورفوتکتونیک,البرز,حوضه آبریز,زمین لرزه,GIS}, url = {https://geoeh.um.ac.ir/article_33921.html}, eprint = {https://geoeh.um.ac.ir/article_33921_3b1cd1809bf2562cc576a81c62836d16.pdf} } @article { author = {Mokarram, Marziyeh and Negahban, Saeed}, title = {Evaluation of Soil Contamination by Heavy Metals around Fasa-Darab Road}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {17-43}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v9i1.85784}, abstract = {Introduction Automobiles are generally one of the major sources of heavy metal pollutants in roadside sediments that enter the environment as particles from the exhaust or other components of the vehicle and pollute the soil and vegetation of these areas (Van Bohemen, 2003). The most common heavy metals in vehicles on the road are Cd, Cu, Pb, Ni and Zn (Elik, 2003; Li, 2001). These heavy metals have a toxic effect on the human body and cause many complications such as blood, nervous and bone diseases (Sarkar, 2002). So, in this study, the amount of heavy metal changes in sediments of road margins Darab-Fasa road was investigated. Al-Chalabi and Hawker (2000) collected samples from three-site soil in Brisbane, Australia, and studied the distribution of Pb around roads. The results showed that vehicle traffic was the main source of pollution, and in areas with more stable climatic conditions, the distribution of Pb in soil was significantly reduced by increasing the distance from the road. The study also found that Pb is accumulated in the first five cms of soil depth. Fakayode and Owolabi-Olu (2003) studied the soil contamination of the streets of Osgbo, Nigeria. By selecting 39 sites with different traffic volumes, they measured the distribution of zinc, nickel, copper, cadmium and lead metals at distances of 5, 15, 30 and 50 meters from the streets. The results showed that with increasing distance from the streets (distance of 50 meters), the concentration of soil metals decreases. Given the importance of the subject, this study investigates the soil contamination to heavy metals in the margins of Darab-Fasa road. In this study, the effect of distance to gas station and its effect on soil pollution was investigated. For this purpose, index of mular and contamination factor (CF), ecological risk index (RI), tolerance contamination index (PLI) were calculated and measured. Study Area The study area is located in the south of Fars province (Darab-Fasa road) at a geographical location of 28 ° 36΄-28 ° 54΄ N and 53 ° 36΄ - 54 ° 30΄ E. Fasa-Darab road with a length of about 100 km has long been considered as the main road connecting Shiraz (Iran's largest city in the southern half of the country) to Bandar Abbas (Iran's largest commercial port). This road has always been used by a variety of light and heavy cars. The cities of Fasa and Darab are the most important demographic centers in the southeast of Fars province, and have a long history and their route is known as one of the busiest roads in Fars province. Materials and Methods For this purpose, soil samples were collected from distance of 2.15 m from two depths of 0-15 cm in a randomized complete block design. Total and absorbable amounts of heavy metals were measured and read with atomic absorption spectrophotometer. Contamination factor (CF) was used to determine soil pollution to heavy elements. Based on this factor, the amount of elements can be measured in relation to its normal value and determine the degree of soil pollution. The contamination factor was calculated according to the following equation for all elements of the study (Hakanson, 1980).                                                           (1) where CFmetal is the ratio of the concentration of each metal (Cmetal) to the concentration of the natural background of that metal (Cbackground). In order to assess the state of soil contamination with heavy metals, the PLI index for the 5 metals under study was calculated. The index, the number of times the concentration of heavy metals in soils and sediments has increased due to pollution and shows a summary of the toxicity of metals (Chan, ., Ng, , Davis, , Yim & Yeung. 2001). The PLI, which is used to study the environmental situation, is defined as the nth root of the multiple concentration of the various metals studied (Angulo, 1996):                                                                      (2) where CFmetal represents the contamination factor of each metal and n is the number of heavy metals studied. The RI index has been used by various researchers such as Wang, Z., Wang, Y., Chen, L., Yan, C., Yan, Y., & Chi, Q.(2015). based on the toxicity of metals. According to Hakanson (1986), the toxicity factor for Cd, Zn, Pb, Cr and Zn metals is 30, 5, 5, 2 and 1, respectively. In this study, the ecological risk potential was calculated based on Eq. 3 and 4.                                                                                (3)                                                                               (4)   Where  is the potential ecological risk index,  and , are the measured value and the normal background values respectively and is the toxicity response factor of the metal. Results and Discussion The results showed that the mean concentrations of Ni, copper, Zn, cadmium, and Pb were 1.20, 2.86, 9.81, 10.08, and 84.17, respectively, which was higher than the local background to Pb, and Cd. The highest amount of heavy metals for the nearest road distance is 5 meters and it is 38.86 mg / kg which decreases with increasing distance from the road. The Igeo index calculated indicates no serious contamination of the area with copper, Zn and Ni metals and only Cd and Pb in the contaminated grade to moderate contamination, and high contamination to highly contaminated were affected. In fact, the results of the Igeo index show that these elements are naturally present in the soil, but anthropogenic activity has increased the concentration of these metals in the soil. Results of CF index showed that Ni, Cuand Zn values ​​were less than 1 and were in low pollution class. Whereas, Pb with values ​​range from 6-6 in high pollution class and Pb is with values ​​greater than 6 in high pollution class. PLI index was used to evaluate and determine the contaminated stations. PLI indicator’s results for the most polluted stations showed that stations 14 and 23 were classified as highly polluted and the rest of the stations were classified as non-polluting. According to RI results, stations 13, 15, 14, 22, 18, 38, 40, 35, 20, 41, 29, 30, 43, 16, 4, 48, 11, 12, 36, 39, 21, 8 have very high risk and other stations have medium risk. Kriging distribution map of RI index of pollution load index showed that the highest RI index is near the gas pump and near urban areas. Furthermore, the results of Kriging interpolating maps showed that Zn, Ni and Pb are found in the southern region (near Darab city), Cd is found in the north (near Fasa city) and Cuin is found in the northern, central and southern parts. Conclusion The results of this study showed that the mean concentrations of Pb, Ni, Zn, Cu and Cd in the roadside margins were higher. Statistically, there was a significant difference between the mean concentrations of Pb, Ni, Zn, Cu and Cd within 5 m of the roads and the values ​​(out-of-town locations and other pollutant sources) and in most observations of concentrations of Pb, Ni , Zn, Cuand Cd are higher than background values. This difference is related to the impact of traffic and transportation factors on the contamination of the roadside. Therefore, caution should be exercised in the application of these soils to create green space and even plant crops. The results also showed that Pb and Cd concentrations in areas close to gas pumps and urban areas were higher than other areas, indicating the impact of human activities.  }, keywords = {pollutants,Heavy metals,Igeo index,CF index,PLI index,RI index,kriging method,road distance}, title_fa = {ارزیابی ریسک اکولوژیکی عناصر سنگین در رسوبات حاشیه جاده‌ها در محیط GIS}, abstract_fa = {فعالیت‌های انسانی ممکن است منجر به تجمع بیشتر فلزات سنگین در رسوبات حاشیه جاده شود. خودروها یکی از منابع تولید فلزات سنگین در جاده‌ها هستند که این آلاینده‌ها به صورت ذرات از اگزوز یا دیگر اجزا خودرو وارد محیط شده و باعث آلودگی خاک این نواحی می‌شود. در این پژوهش میزان تغییرات فلزات سنگین در رسوبات حاشیه جاده تحت تأثیر تردد وسایل نقلیه در جاده فسا- داراب (استان فارس) مورد بررسی قرار گرفت. بدین منظور نمونه‌های خاک از فواصل ۵ و15 متری حاشیه جاده از دو عمق 0-15 سانتیمتری در قالب طرح بلوک کامل تصادفی به صورت فاکتوریل (عمق و فاصله) جمع آوری گردید. مقادیر کل و قابل جذب عناصر سنگین اندازه گیری و با دستگاه جذب اتمی قرائت گردید. شاخص محاسبه شاخص مولر و فاکتور آلودگی (CF)، شاخص ریسک اکولوژیکی (RI)، شاخص بار آلودگی تاملینسـون (PLI) کـه برای تعیین میزان آلودگی منطقه مورد مطالعه بر روی 5 عنصر کادمیوم، سرب، مس، روی و نیکل مورد محاسبه قرار گرفتند. نتایج نشان داد، مقدار غلظت میانگین عناصر نیکل، مس، روی، کادمیوم، و سرب به ترتیب 1.20، 2.86، 9.81، 10.08، و 84.17 میلی گرم بر کیلوگرم می‌باشد که غلظت سرب و کادمیوم بالاتر از مقدار پس زمینه محلی بود. بیش‌ترین مقدار فلزات سنگین برای نزدیکترین فاصله از جاده یعنی ۵ متری از آن می‌باشد و مقدار آن ۸۶/۳۸ میلی گرم بر کیلوگرم می‌باشد که با افزایش فاصله از جاده کاهش می‌یابد. شاخص زمین انباشتگی (Igeo) محاسبه شده براساس میانگین شیل و مقدار پس زمینه محلی نشان دهنده عدم آلودگی جدی منطقه به فلزات مس، روی و نیکل است و تنها کادمیوم و سرب در کلاس آلوده تا آلودگی متوسط، و آلودگی زیاد تا بشدت آلوده به ترتیب قرار گرفتند. نتایج حاصل از نقشه‌ها پهنه بندی به روش کریجینگ نشان داد که روی، نیکل و سرب در جنوب منطقه (نزدیکی شهر داراب)، کادمیوم در شمال (نزدیکی شهر فسا) و مس در بخش‌هایی از شمال، مرکز و جنوب بیشترین مقدار را داشتند.}, keywords_fa = {آلاینده,فلزات سنگین,شاخص Igeo,شاخص CF,شاخص PLI,شاخص RI,روش کریجینگ,فاصله از جاده}, url = {https://geoeh.um.ac.ir/article_33936.html}, eprint = {https://geoeh.um.ac.ir/article_33936_837b7ceb62cc365ccbae362928d3b3fb.pdf} } @article { author = {Azadi, Fahimeh and Sadough, Seyed hasan and Ghahroudi, Manigeh and Shahabi, Himan}, title = {Zoning of Flood Risk in Kashkan River basin using Two Models WOE and EBF}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {45-60}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v9i1.83090}, abstract = {1. Introduction Among natural disasters, floods are of the most devastating. The accurate assessment of its dangers has failed at various scales due to lack of information and knowledge about flood losses. During heavy rains, flow in a river increases rapidly and the water level rises above normal and covers the floodplain and its surroundings and causes floods. Catastrophic floods occur in the Kashkan River basin every year. Due to the abundance of floods in this region, flood sensitivity maps should be considered to prevent loss of life and economic damage. From 1955 to 2011, the Kashkan River was faced with 16 floods with a volume of more than 1000 cubic meters per second, which was one of the most severe floods in 2019 in this river. The April 2019 flood was one of the most unprecedented floods that’s recorded in the last 200 years; therefore, the development of flood sensitivity maps and river area preparation to identify flood areas in the watershed is essential to improve flood management and decision making. The main purpose of this study is to evaluate the performance of the weighted evidence function and the definitive evidence function to prepare a flood susceptibility map in the Kashkan River watershed. 2. Study Area Kashkan River is one of the most important and full of water branches of Karkheh river which collects the waters of a large area of Lorestan province. This river joins Seymareh river in the southwest of Poldokhtar in an area called Kol-e-Sefi and forms Karkheh river. The length of Kashkan river is about 270 km and its catchment area upstream of Kashkan-Poldakhtar station is 9400 square kilometers. The main drainage system of the Kashkan river first consists of the join together branches of the Hero and Aleshtar doab rivers in the northeast and north of the basin, respectively, from east to west and north to south. These tributaries which originate from the high and snow capped Garin and Misho paro mountains along the main route joins other sub-rivers such as Cham Zakaria, Khorram Rud, Chulhol, and Madian Rivers. The largest recorded flood in the province was the flood on April 1, 2019 in Kashkan River with a peak discharge of 6500 cubic meters per second. The amount of damage caused by it in different sectors was estimated 11 thousand billion Tomans (report of the provincial crisis headquarters 2019). 3. Materials and Methods The geographical location map of 260 flood points in the region was prepared based on the information of Lorestan Regional Water Company. This set was randomly divided into two groups including training group data (70%) and validation group data (30%). In this study several factors used including slope percentage, slope direction, height, distance from river, river density, distance from road, land use, soil type, slope curvature, lithology, vegetation, rainfall, NDVI, stream capacity index (SPI) And topographic wet index (TWI) were considered for zoning of flood risk potential. It should be noted that the classification of the layers was done according to the conditions of the region and experts’ opinion. The tools used in this study were divided into two parts: physical tools including DEM maps, geological maps, land use and waterway, and conceptual tools including ArcGIS and Excel software. Two methods, WOE and EBF, were used. The WOE method or evidence weight method is a data-driven method used to combine data sets and is based on the use of a linear form of the Bayesian probability model to estimate the relative importance of evidence using statistics. The EBF method includes several parameters Bel or degree of confidence, Dis degree of uncertainty, Unc or degree of uncertainty, and Pls degree of reasonableness in the range between zero and one. The main part of this theory is presented by the degree of certainty and the degree of reasonableness, so the degree of reasonableness is greater than or equal to the degree of certainty. Data extracted from EBF not only estimates the spatial correlation between effective factors and flood occurrence but also the spatial correlation between classes of each effective factor. 4. Results and Discussion According to the model of gravitational evidence and the function of conclusive evidence, southeast direction, slope of 0-5%, altitude of 448-900 m, soil type (Inceptisol/Vertisol), distance from the river (0-50), river density (0.43-0.69), residential use, rain ( 348-450mm), concave slope curvature, Lithology (OMq), TWI (high floor), SPI (very low), NDVI (very low) and the distance from the road (200-150 meters) have the greatest impact on creating flood potential. The maps obtained from the EBF model include degrees of certainty (Bel), uncertainty (Dis), unreliability (Unc) and probability (Pls) in the range between zero and one, and the sum of the values of certainty, uncertainty and unreliability is 1. As can be seen 47/32% of the study area is in the medium to very high risk class. Among the studied WOE and EBF models, the highest accuracy was attributed to the EBF model (0.875); Therefore, in terms of flood risk potential, the EBF model performs better than the WOE model. 5. Conclusion In this study, two models, EBF and WOE, were used to predict flood risk potential. The largest area of areas with very high potential was observed in the WOE model. The results of the study showed that flooding is the result of various environmental and human factors. Based on the presented flood risk forecast map, appropriate management measures can be taken to reduce flood damage and casualties. Areas that have a very high potential for flooding according to the final plan should be given more attention while planning.}, keywords = {Flood,Kashkan River Watershed,WOE Model,EBF Model}, title_fa = {پهنه‌بندی حساسیت خطر سیل در حوضه آبخیز رودخانه کشکان با استفاده از دو مدل WOE و EBF}, abstract_fa = {سیل یکی از خطرناک‌ترین و شایع‌ترین حوادث طبیعی است که در سراسر جهان اتفاق می‌افتد. در استان لرستان و در حوضه آبخیز رودخانه کشکان نیز، این بلای طبیعی یکی از پرتکرارترین حوادثی است که هرساله اتفاق می‌افتد و علاوه بر خسارات مالی فراوان جان برخی از مردم منطقه را نیز به کام مرگ می‌برد. در فروردین سال 98 سیلی که اتفاق افتاد، یکی از بی‌سابقه‌ترین سیل‌های ثبت شده در 200 سال اخیر بود؛ بنابراین، توسعه نقشه‌های حساسیت سیل و تهیه حریم رودخانه، برای شناسایی مناطق سیلاب در حوضه آبخیز برای بهبود مدیریت و تصمیم‌گیری سیل ضروری است. هدف اصلی این مطالعه ارزیابی عملکرد تابع شواهد وزنی و تابع شواهد قطعی برای تهیه نقشه حساسیت سیلاب در حوضه آبخیز رودخانه کشکان است. این مقاله با استفاده از وزن عوامل یا شواهد وزنی  (WoE)و مدل شواهد قطعی (EBF) بر اساس سیستم اطلاعاتی جغرافیایی (GIS)  در حوضه رودخانه کشکان نقشه حساسیت منطقه به سیلاب را بدست آورده است، که در آن موقعیت جغرافیایی 260 نقطه سیل گیر مشخص شده در منطقه به صورت تصادفی به یک گروه متشکل از (۷۰ درصدی) برای واسنجی و یک گروه (۳۰ درصدی) برای اعتبارسنجی تقسیم شدند. هر دو مدل 14 فاکتور مؤثر در ایجاد سیل را مورد توجه قرار داده‌اند که عبارتند از: شیب، جهت شیب، زمین‌شناسی، جنس خاک، کاربری اراضی، شاخص رطوبت توپوگرافی (TWI)، توان آبراهه (SPI)، بارش، فاصله از رودخانه، فاصله از جاده، پوشش گیاهی (NDVI)، انحنای شیب (Curvatior)، تراکم آبراهه و مدل ارتفاعی رقومی منطقه. همچنین برای اعتبار سنجی، نتایج مدل‌ها از منحنی راک استفاده شد. بر اساس مدل  EBF، 32/47 درصد از سطح منطقه در کلاس خطر متوسط تا خیلی زیاد قرار دارد و بر اساس مدل WOE حدود 8/52 درصد از سطح منطقه در کلاس خطر متوسط تا خیلی زیاد قرار دارد. به‌منظور اعتبارسنجی نقشه‌های پیش‌بینی پتانسیل سیل‌خیزی، از منحنی ROC استفاده شد. از بین دو مدل WOE و EBF، بیشترین صحت به مدل‌ EBF (875/0) اختصاص داشت؛ بنابراین در زمینه پتانسیل‌یابی خطر سیل‌خیزی، مدل EBF نسبت به مدل WOE دارای عملکرد بهتری است.}, keywords_fa = {سیل,حوضه آبخیز رودخانه کشکان,مدل WOE,مدل EBF}, url = {https://geoeh.um.ac.ir/article_33950.html}, eprint = {https://geoeh.um.ac.ir/article_33950_dc4fa9a5a42c26513783121663261b27.pdf} } @article { author = {Rezaei Moghaddam, Mohammad Hossein and Hejazi, Seid Asadollah and Vlaizadeh Kamran, Khalil and Rahimpoor, Tohid}, title = {Analysis of Hydrogeomorphic Properties of Aland Chai Basin to Prioritize Sub-Basins in terms of Flood Sensitivity}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {61-83}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v9i1.84675}, abstract = {Introduction Flood is a disaster which causes a lot of economic damages to farmlands, forests, gas and power transmission lines, roads, engineering structures, and buildings. There are numerous floods in the northwest of the country at the beginning of spring and the start of spring rains, which in most cases results in heavy damage. The purpose of this study is Geographic Information System (GIS)-based analysis of hydrogeomorphic properties of Aland Chai Basin for preparing flood sensitivity map. To this aim, hydrogeomorphic parameters of sub-basins have been studied from three aspects of drainage network characteristics (e.g., stream order, streams number, streams length, stream frequency, bifurcation ratio, length of overland flow, drainage density, drainage texture, texture ratio, infiltration number, constant of channel maintenance, and rho coefficient), basin geometry (e.g., basin area, compactness coefficient, circulatory ratio, elongation ratio, form factor, and shape factor) and relief properties (relief, relief ratio, ruggedness number, and gradient). Study area Aland Chai basin is located between 38, 30´ and 38, 48´ N and between 44, 15´ and 45, 01´ E in the West Azerbaijan province. It covers an area of 1147.30 km2 and it is situated in the north-western part of Iran. This basin is one of the sub-basins of the Aras River basin to which surface water flows after joining the grand Qotour River. Basin elevation variations are from 1093m in the Aland Chai River bed to 3638m above sea level in the Avrin Mountain. Figure 1. The study area location in the West Azerbaijan province Materials and Methods The Step-Wise Weight Assessment Ratio Analysis (SWARA) model was introduced to the provided relational database in weighting of data layers. SWARA technique is one of the multi-criteria decision methods which was developed by Keršuliene et al. (2010). In this method, an expert has an important role in evaluating and calculating weights. Based on this method, the most signifcant criterion is ranked as the first, while the least signifcant one is ranked as the last. Results and Discussion Hydrogeomorphic analysis plays an important role in the analysis of hydrological behavior of the basins. In the present study, 22 hydrogeomorphic parameters were analyzed from three aspects of drainage network characteristics, shape parameters, and relief properties in order to investigate the role of these parameters in flood sensitivity of Aland Chai basin. Digital Elevation Model (DEM) with 12.5m spatial resolution and ArcGIS software were used to generate the data layers maps. In the next step, all necessary weights were calculated for factors and Sub-basins using SWARA model. According to a comparison between factors for each sub-basin, it was specified that sub-basins 3, 1, 4, and 2 (weighted as 0.142, 0.122, 0.091, and 0.087) have the highest impacts on Flood occurrence in study area. On the contrary, sub-basins 13 and 6 (weighted as 0.018 and 0.020) show the lowest weight. Conclusion In this study, an attempt was investigated to identify sub-basins with high potential for flood occurrence in Aland Chai basin. Based on the effective parameters, flood occurrence inside of Aland Chai basin could be separated into 5 distinguished classes from very high to very low flood susceptibility. According to the SWARA-based flood susceptibility map, sub-basins 3, 1, 4, and 2 of the study area have very high potential, sub-basin 7, 15 and 11 have high susceptibility, sub-basin 12, 5, and 9 have moderate susceptibility, sub-basins 8, 10, and 14 have low susceptibility, and sub-basins 6 and 13 have very low susceptibility toward flood occurrence. The total area of sub-basins in the high and very high class of flood is 656.72 km2, which comprises 57.24% of the total Aland Chai basin. Therefore, according to the results of the study, it is necessary to take protective measures such as watershed planning and dam construction in the sub-basins that are highly sensitive to prevent flood or reduce potential damages in case of flooding.  }, keywords = {Flood,Hydrogeomorphic analysis,Prioritization,GIS,SWARA,Aland Chai Basin}, title_fa = {تحلیل خصوصیات هیدروژئومورفیک حوضه آبریز الندچای به منظور اولویت‌بندی زیر حوضه‌ها از نظر حساسیت سیل خیزی}, abstract_fa = {تحقیق حاضر با هدف اولویت‌بندی زیر حوضه‌های حوضه آبریز الند چای واقع در استان آذربایجان غربی از نظر حساسیت سیل­خیزی انجام گرفته است. برای نیل به این هدف، ابتدا حوضه آبریز الندچای بر اساس خصوصیات شبکه زهکشی و توپوگرافی و با استفاده از مدل رقومی ارتفاعی (DEM) با قدرت تفکیک مکانی  5/12 متر به 15 زیر حوضه‌ تقسیم شد. در مرحله بعد پارامترهای ژئومورفومتریک هر زیر حوضه از سه جنبه خصوصیات شبکه زهکشی (شامل رتبه آبراهه، تعداد آبراهه، طول آبراهه، تناوب آبراهه، نسبت انشعاب، طول جریان در روی زمین، تراکم زهکشی، بافت زهکشی، نسبت بافت، شماره نفوذ، ثابت نگه داشت کانال و ضریب رو)، پارامترهای شکلی حوضه (شامل مساحت، ضریب فشردگی، نسبت مدور بودن، نسبت کشیدگی، ضریب شکل و شاخص شکل) و خصوصیات برجستگی حوضه آبریز (شامل برجستگی، نسبت برجستگی، عدد سختی یا زبری و نسبت شیب) با به‌کارگیری قوانین ژئومورفولوژیکی هورتن، شوم و استرالر در محیط نرم‌افزار ArcGIS تهیه شدند. به‌منظور وزن دهی 22 پارامتر مورد بررسی در تحقیق حاضر از روش وزن دهی نوین SWARA استفاده شده و وزن نسبی هر یک از پارامترها برای 15 زیر حوضه مورد مطالعه مشخص گردید. نتایج وزن دهی و اولویت­بندی نشان داد که زیر حوضه‌های 3، 1، 4 و 2 به ترتیب با وزن 142/0، 122/0، 091/0 و 087/0 بیش‌ترین وزن را داشته‌ و از حساسیت سیل­خیزی بالایی برخوردار می‌باشند. در مقابل زیر حوضه 13 با وزن نهایی 018/0 و زیر حوضه 6 با وزن 020/0 به ترتیب کم‌ترین وزن را از نظر 22 پارامتر مورد بررسی داشته و درنتیجه در طبقه خیلی کم از نظر حساسیت سیل­خیزی قرار دارند.}, keywords_fa = {سیل,تحلیل هیدروژئومورفیک,اولویت‌بندی,GIS,SWARA,حوضه آبریز الندچای}, url = {https://geoeh.um.ac.ir/article_33968.html}, eprint = {https://geoeh.um.ac.ir/article_33968_9cf6298ed537f6ed100c4b2e829190f2.pdf} } @article { author = {Jafari, Fahimeh and Shayan, Hamid and Bataghva Sarabi, Homa}, title = {Analysis of Key Factors Affecting the Promotion of Resilience of Rural Settlements against Environmental Hazards (Case Study: Rural Settlements of Fariman City)}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {85-115}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v9i1.86846}, abstract = {1. Introduction There are dramatic changes in attitudes toward risk today; thus, the prevailing view has shifted from focusing solely on reducing "vulnerability" to increasing "resilience" to disasters. Resilience is a kind of futurism emerging due to the dynamic response of society to risks which can have an impact on expanding policy choices to deal with uncertainty and changes. Accordingly, on a global scale, in a situation where risks and uncertainties are rising, efficient natural disaster planning and management strategies are highly required. As a result, human societies can reduce vulnerability at different levels, especially at the local level. Accordingly, one of the most effective approaches in risk management, planning, and increasing the resilience of rural settlements is the futuristic approach., uncertainties in the planning process can be detected and managed by analyzing the main factors and drivers of development. 2. Study Area The study area in this research is the rural settlements of Fariman. Fariman is one of the cities of Khorasan Razavi. In 2016, it had a population of 99001 people and consisted of two central parts of Qalandarabad and five villages named Fariman, Sang Bast, Balaband, Sefid Sang, and Qalandarabad. It has a total of 177 inhabited villages.  Fariman Sangbast, Qalandarabad, Kalateh Minar, and Barashk rivers flow to this region while it is located on an active fault. The studied villages include 29 villages in Qalandarabad district who have suffered human and financial losses due to floods and earthquakes. According to the city governor's office, in villages where the earthquake occurred, about 40 to 100 percent has been destroyed. Besides, according to the city housing foundation, 285 rural housing units and 324 livestock places have been damaged due to the flood for about 10 to 100 percent. More importantly, 200 hectares of wheat and saffron fields in Fariman have been damaged due to flood. In general, about 15 billion tomans of the damage has been caused by floods to farms, livestock, and roads in Qalandarabad, Fariman.   Figure 1. Introduction of the Study Area 3. Materials and Methods The present research is an applied one in terms of purpose and nature which is conducted using new methods of futures studies, analytical, and structural ones. It is a mixed methods approach using a combination of both quantitative and qualitative models. The present study identifies the most important factors affecting the promotion of resilience of rural settlements against environmental hazards in Fariman. To this end, Delphi technique has been applied to identify variables and indicators. In this regard, first, to collect the variables, published scientific-research articles on the factors affecting the increase of resilience against environmental hazards were used. Then, a semi-structured questionnaire was designed and distributed using selected Delphi method in several stages among selected experts - experts in the field of research and rural managers. In order to consciously select the participants, purposive sampling method was used. The statistical population of the present study is 50 people including 29 villagers and members of Islamic councils of the studied villages while 21 others involved 8 university professors, 7 doctoral students and specialists in the study area, 3 experts of the housing foundation of the Islamic Revolution of Khorasan Razavi, and 3 experts of the city governors. The applied futuristic method of the study is used for cross-impact analysis. This method is an expert-centered method through which a few results are obtained. The method is based on the analysis of interactions in the matrix. In crossover effects analysis, events along with events and trends are considered as independent variables and the probabilities of the phenomenon in the future are plotted by examining the output (in pairs) of the effective variables or drivers (in the column row). This method uses Mick Mac software. 4. Results and Discussion Based on the results of the number of variables, the dimensions of the 47 ×47 matrix are set in six different domains. The results show that the number of repetitions is double and the degree of matrix filling is 75.73%. The results indicate that the number of high-intensity relationships accounted for a higher percentage. How variables are distributed on the scatter plot determines the stability and instability of the system. The status of distribution and the dispersion of variables affecting the promotion of resilience of rural settlements against environmental hazards in the distribution plate indicates that the status of the system is unstable. So, the most variables are scattered around the diagonal axis of the plane. To analyze the system environment and finally to identify the drivers and key effective factors, the impact plan and the variability of variables are examined along with the ranking and displacement of variables. Due to the instability of the system,  five types of variables including effective variables, two-dimensional variables, regulatory variables, affective variables, and independent variables were identified. Moreover, the system shows the sum of influential variables and their interactional effect. Among the research variables, social variables had the highest impact on increasing the resilience of rural settlements and environmental hazards while environmental-physical variables had the lowest impact. Comparing the results of direct and indirect effects analysis, the key factors affecting the promotion of resilience of rural settlements against environmental hazards were detected. According to the results, the key driving forces in terms of the impact on the 16 key factors are more important, both in direct and indirect effects. Finally, the key factors affecting the increase in resilience were ranked from highest to lowest. 5. Conclusion In the present study, 16 factors were selected as the most prominent ones including the increase in people's cooperation and convergence in times of danger, accountability of government organizations and local institutions, partnership between communities, the private sector and local authorities, taking the necessary measures to protect the village from hazards by local management, strong buildings for use in times of danger, granting credit and loans to victims, coordination between different institutions and timely supervision to provide assistance, increasing non-agricultural incomes of villagers, use of GIS in natural hazard management by relevant organizations, informing people about ways to deal with accidents, rehabilitation of residential units with the advice of local architects and engineers, use of information tools by relevant institutions, access to organizations for post-accident management, training people to build durable structures, creating insurance coverage in various aspects, and training and maneuvering by government agencies. The problems regarding the crisis management can be solved and the effects of natural disasters in the city of Fariman will be reduced if only these factors are well taken into account.}, keywords = {Environmental risk management,Resilience,rural settlements,Awareness and participation,Futures Studies}, title_fa = {شناسایی و تحلیل پیشران های کلیدی مؤثر در ارتقاء تاب آوری سکونتگاه های روستایی در برابر مخاطرات محیطی (مطالعه موردی: سکونتگاه های روستایی شهرستان فریمان)}, abstract_fa = {سکونتگاه­های روستایی به دلیل نارسایی زیرساخت­های ضروری، آسیب­پذیری بالایی در برابر مخاطرات محیطی دارند. براین اساس با وقوع مخاطرات محیطی خسارت­های جبران­ناپذیری بر این سکونتگاه­ها وارد می­شود؛ لذا جهت کاهش خسارت­های ناشی از مخاطرات، افزایش سطح تاب­آوری در برابر مخاطرات بسیار ضروری است. پژوهش حاضر به دنبال شناسایی پیشران­های کلیدی جهت افزایش تاب­آوری سکونتگاه­های روستایی شهرستان فریمان در برابر مخاطرات است. روش پژوهش براساس روش جدید علم آینده‌پژوهی تحلیلی- ساختاری با به‌کارگیری ترکیبی از مدل­های کمی و کیفی است. با استفاده از روش­های دلفی و تحلیل اثرات متقابل به وسیلۀ نرم­افزار MICMAC عوامل کلیدی مؤثر در افزایش تاب­آوری سکونتگاه­های روستایی در برابر مخاطرات شناسایی و تحلیل شده­اند. جامعۀ آماری پژوهش 50 نفر که شامل 29 نفر از دهیاران و اعضای شوراهای اسلامی روستاهای مورد مطالعه و 21 نفر دیگر نیز شامل افراد متخصص در حوزه مورد بررسی می­باشند. براساس نتایج به‌دست‌آمده 16 عامل بالا بردن همکاری و همگرایی مردم در زمان مخاطره، مسئولیت­پذیری سازمان­های دولتی و نهادهای محلی، مشارکت میان جوامع، بخش خصوصی و مقام­های محلی، اتخاذ تدابیر لازم برای حفظ روستا از خطر مخاطرات توسط مدیریت محلی، بناهای مستحکم جهت استفاده در زمان خطر، اعطای اعتبارات و وام به آسیب­دیدگان، هماهنگی میان نهادهای مختلف و رسیدگی به‌موقع جهت کمک­رسانی، افزایش درآمدهای غیرکشاورزی روستاییان، استفاده از GIS در مدیریت مخاطرات طبیعی توسط سازمان­های ذی­ربط، آگاه­سازی مردم از راه­های مقابله با وقوع حوادث، مقاوم­سازی واحدهای مسکونی با مشاوره معماران محلی و مهندسین، استفاده از ابزارهای اطلاعاتی از سوی نهادهای ذی‌ربط، دسترسی به سازمان­ها برای مدیریت بعد از وقوع حوادث، آموزش مردم جهت ساخت­وسازهای مقاوم، ایجاد پوشش بیمه­ای در جنبه­های مختلف، آموزش و اجرای مانور توسط دستگاه­های دولتی مهم­ترین عوامل کلیدی مؤثر در افزایش تاب­آوری سکونتگاه­های روستایی در برابر مخاطرات محیطی شهرستان فریمان محسوب می­شوند.}, keywords_fa = {مدیریت مخاطرات محیطی,تاب آوری,سکونتگاه های روستایی,آگاه‌سازی و مشارکت,مقاوم‌سازی}, url = {https://geoeh.um.ac.ir/article_33982.html}, eprint = {https://geoeh.um.ac.ir/article_33982_8349d69a023dd6a72dac66c62dfb2410.pdf} } @article { author = {Kavakebi, Ghazale and Mousavi Baygi, Mohammad and Alizade, Amin and Mosaedi, Abolfazl and Jabbbari Nooghabi, Mehdi}, title = {Presenting a Model for Predicting Meteorological and Hydrological Drought Risk by Statistical Methods under the Influence of Climate Change (Case study: Afin Catchment Area)}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {117-137}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v9i1.84991}, abstract = {Introduction Drought is a common, natural climate phenomenon on the earth with various effects on the economic, social, and environmental aspects of life. The impact of drought on agriculture, water access, and socioeconomic activities of the region depends on various physiological, environmental, and social factors. Due to declined rainfall in specific and efficient periods, drought could lead to water scarcity. Hydrological drought is defined as the reduction of available water in all its forms (Ma, Ren, Singh, Yuan, Chen, Yang, & Liu, 2016). Climate change could influence the frequency and severity of droughts. Therefore, drought vulnerability depends on several factors, such as topographic features, development of soil, land, and water resources, groundwater utilization, and the regional water demand for domestic, industrial, and agricultural activities. Since these impacts may be local or regional, it is difficult to evaluate the effects of drought on various sectors. Risk is often recognized as the combined probability of a specific event (e.g., drought) and its negative consequences. Risk is defined as the endangerment of a system, which could often be the environment, where drought is interpreted as an environmental risk. The response of the environment to a hazard depends on the severity of the hazard and environmental properties, which could be classified into four categories of economic, social, physical, and environmental factors. The previous studies in this regard have mainly introduced economic and social factors as the risk factors for the occurrence of droughts. In the aforementioned studies, field questionnaires have not been used to assess drought vulnerability, while in the present study, the main research instrument was a questionnaire to estimate drought vulnerability. The present study aimed to assess the risk status of drought in a region in Iran based on observational data and the climatic downscaled data obtained from the coordinated regional climate downscaling experiment (CORDEX) project in order to predict the risk of drought. Study Area Afin sub-basin covers an area of 655 square kilometers. The Afrin basin is between 33 degrees and 42 minutes north to 33 degrees and 58 minutes north and 52 degrees 35 minutes east to 53 degrees and 31 minutes north. Khoshbakht river is the permanent river of this basin and part of a larger sub-basin known as Esfedan, which is connected to Zuzan (northeast) and Khaf salt pan. It is also connected to Qaen (northwest), Sharokht (southeast), and Saddeh and Birjand (southwest). The average precipitation in Afin sub-basin is approximately 156.4 millimeters, and the average temperature in the region is 14.7°C (Figure 1). Based on the climate classification methods proposed by Amberje, the climate of Afin sub-basin is arid-cold. The arid-cold climate of the area is suitable for the growth of barberries. The economy of the village in the vicinity of Afin sub-basin has historically relied on agriculture, especially the cultivation of barberries. In fact, most of Iran's barberry is produced in this region. Materials and Methods At the first stage, the standardized precipitation evapotranspiration index (SPEI), effective reconnaissance drought index (eRDI), and standardized runoff index (SRI) were applied as the hydrological indices in this regard. The base period was the year 1983, and the utilized data included the monthly data on the average maximum temperature, average minimum temperature, mean surface air temperature, precipitation, and river flow data of Khoshbakht River in Afin sub-basin. Drought Hazard is defined as the probability of drought occurring at various levels of severity. In the current research, the probability of drought occurrence, and the probability of drought occurrence in each drought class was calculated using the normal z-score table. Vulnerability is a set of economic, social, and environmental conditions, which determine the sensitivity of an environment to risk. In the present study, a questionnaire consisting of 35 items was prepared in order to identify the extent of the impact of each vulnerability factor, and exploratory factor analysis and confirmatory factor analysis were applied to determine the vulnerability level of the selected area. Risk is defined as the result of the interactions between a system (environment), natural hazards, and socioeconomic vulnerability relative to the risk. The level of drought risk could be estimated after calculating the drought hazard and its vulnerability based on the definition of risk. In order to access the required meteorological data in the future (as mentioned in the Methodology section) and due to the level of access to the CORDEX project data, only three models of GFDL-ESM2M, CNRM-CERFAC, and ICHEC-EC-EARTH were selected in the current research since all the required meteorological parameters must have historical data, RCP4.5, and RCP8.5. In the present study, the IHACRES model was utilized to obtain the future runoff data. Since the vulnerability level obtained by the questionnaire was considered constant over time in the modeling of drought risk, hazard modeling was carried out. After the prediction of the hazard, future drought risk was estimated by multiplying the vulnerability value as described in the previous section. Two methods were exploited for the modeling of the drought risk, including the bootstrapped quantile regression (500 repetitions) and loess nonparametric regression. Results and Discussion Correlation-coefficient (R), explanation coefficient (R2), and Nash-Sutcliffe coefficient (NS) were used to assess the predictive ability of the climate models. After correction, the combined model for the precipitation and temperature parameters was determined using the weighted average method and Bayesian approach. According to the obtained results, the ICHEC-EARTH model had the highest coefficient as an integrated model based on the RCP4.5 scenario.  Based on the two scenarios, the amount of runoff will have no significant changes in the upcoming years. Increased temperature and the subsequent probability of excessive rainfall in the studied area may be the reason for the lack of runoff in the upcoming years. Based on the completed questionnaires, the vulnerability score was 0.53 for Afin sub-basin, which indicated that about half of the sub-basin vulnerability was due to the economic, social, and environmental factors of the sub-basin. Furthermore, the vulnerability value was considered to be a mediator of the sensitivity of the mentioned factors. According to the results based on the mentioned meteorological drought indices, most variations in the drought risk were observed in winter. The results of drought risk assessment indicated that most variations in the frequency of droughts occurred in winter compared to the base season. On the other hand, the SRI findings showed no significant risk of severe droughts in any of the time scales within the next three periods based on the RCP4.5 and RCP8.5 scenarios. Conclusion The present study aimed to provide a model to predict the drought risk status in the future in the form of a case study of Afin sub-basin in Iran based on the meteorological drought indices of SPEI and eRDI and hydrological drought index of SRI. In general, the obtained results could be summarized as follows: SPEI and eRDI had the same performance in estimating the frequency of drought events, while eRDI showed higher drought intensity compared to SPEI, which could be due to the use of effective precipitation as an input in this index. In addition, SPI and eRDI indicated approximately equal drought severity. A slight increase was observed in the runoff of the future years based on the RCP8.5 scenario. Based on the meteorological drought indices, the possibility of highly severe droughts within the next 27 years is lower compared to the mid and far future periods. The meteorological drought indices showed that most drought changes in the investigated time scales occur in winter.}, keywords = {Drought Hazard,Drought Vulnerability,Drought risk,Climate change}, title_fa = {ارائه مدل پیش‌بینی ریسک خشکسالی هواشناسی و هیدرولوژیک با روش‌های آماری تحت تأثیر تغییرات اقلیمی (مطالعه موردی: زیرحوضه آبریز افین)}, abstract_fa = {خشکسالی یکی از پدیده­های طبیعی در اقلیم­های مختلف با ویژگی­ تکرار شونده است که به علت داشتن ویژگی‌هایی نظیر شروع، خاتمه، شدت و فراوانی، دارای پیچیدگی‌هایی در مقایسه با سایر مخاطرات طبیعی است و گستره وسیعی از ابعاد محیط طبیعی و جوامع انسانی را تحت تأثیر خود قرار می‌دهد؛ ازجمله بخش­های اقتصادی، اجتماعی و زیست‌محیطی. در این پژوهش سعی شده تا مدلی برای پیش­بینی ریسک خشکسالی، ارائه و اقدامات لازم به­منظور کاهش اثرات ناشی از آن انجام شود. بدین منظور از شاخص­های خشکسالی هواشناسی SPEI و eRDI و شاخص خشکسالی هیدرولوژیک (SRI) استفاده شد. به‌منظور بررسی تأثیر تغییر اقلیم بر این پدیده، دو سناریوی انتشار خوش­بینانه و بدبینانه مورد بررسی قرار گرفت. دوره پایه این مطالعه 2015-1983 و دوره پیش‌بینی ریسک خشکسالی سال­های 2100-2020 است. دو روش مدل­سازی BQR و loess Nonparametric Regression برای مدل‌سازی ریسک خشکسالی استفاده شد. نتایج بدست‌آمده از این مطالعه حاکی از کاهش نسبی در وقوع دفعات خشکسالی در 27 ساله آینده نزدیک در زیر حوضه آبریز افین است. همچنین مقایسه روش­های مختلف نشان از مناسب بودن مدل رگرسیون ناپارامتری برای پیش­بینی ریسک خشکسالی آینده را داشت.}, keywords_fa = {مخاطره خشکسالی,آسیب‌پذیری خشکسالی,مدل‌های اقلیمی,RCP4.5,RCP8.5}, url = {https://geoeh.um.ac.ir/article_34000.html}, eprint = {https://geoeh.um.ac.ir/article_34000_a9cf441f9b32a98eacb2fbea6852c6eb.pdf} } @article { author = {Baghi, Maliheh and Rashki, Alireza and Mahmudy Gharaie, Mohamad Hosein}, title = {Investigation of Chemical and Mineralogical Properties of Dust Entering Northeastern Iran and its Pathogenic Potential}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {139-153}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v0i0.79993}, abstract = {Introduction Dust is one of the most important natural hazards in the world, especially on the edge of deserts and arid and semi-arid climates. In summer, dust storms caused by 120-day winds that originate from Karakum  Desert in southern Turkmenistan and sometimes the dry bed of the Aral Sea affect the northeastern parts of Iran and endanger the living conditions of the inhabitants of these areas. In order to understand the effect of dust on health, the chemical properties of dust entering these areas have been studied. For this purpose, a sampler was installed on the border of Iran and Turkmenistan (Sarakhs) and Iran and Afghanistan (Taybad). Sampling was done monthly from July to September 2017 and the mineralogical and chemical properties of dust were done using ICP and XRD methods. The results showed that among the main elements, calcium, aluminum and silicon have a higher percentage, respectively, and there are significant amounts of trace elements like B, S, Ba and Sr than other elements in the region. Quartz, calcite, dolomite and montmorillonite minerals have a higher percentage than other minerals among the studied samples. The presence of heavy elements such as arsenic, lead, tungsten, cadmium and iron in dust samples at high concentrations may lead to sinusitis, bronchitis, asthma and allergies, and damage the defense function of macrophages, which leads to increased nosocomial infections. Study Area East of Greater Khorasan is affected by strong wind currents, usually known as 120-day winds or Lavar winds. These winds usually blow from north to south in spring and especially in summer, and eventually lead to dust storms, especially in Sistan region, but the deserts in Turkmenistan, especially Karakum desert is one of the major dust distribution areas and has been introduced in East Khorasan, but other local sources in Afghanistan as well as in Iran are among the dusty areas. Sarakhs city, as the easternmost city of Khorasan Razavi, is the first region to be affected by this dust coming from Turkmenistan, and then Taybad city, due to its proximity to Afghanistan, can also receive dust from Afghanistan. For the mentioned reasons, these two areas were selected as dust sampling areas.   Figure1. Sampling installation location map Materials and Methods First, various studies on the chemical and mineralogical properties of dust, tracking its transmission paths using the HYSPLIT model in Iran and the world were reviewed. In the next step, meteorological data were processed with the help of which the region's wind was drawn to detect the direction and frequency of dust-carrying winds to have an overview of the region's wind conditions. Then, to track the movement of air masses during the occurrence of dust storms in the area, the Lagrangian model of Hysplit was used. For this purpose, after identifying the dust days in each of the studied stations, the trajectory of air mass movement was calculated and its map was prepared and drawn. In the next stage, suitable sampling equipment was designed and installed in the direction of the prevailing wind in the northeastern borders of the country, near the border of Turkmenistan and Afghanistan in summer, when the frequency of high dust phenomenon occurs. Visits and collection of collected samples of equipment were performed over a period of four months. At the end of each month, samples were collected from sedimentary and transit samples and transferred to Ferdowsi University Central Laboratory for ICP-OES analysis and identification of major and minor elements in the samples. Chemical analysis of dust particles can identify heavy metals as well as trace elements that are commonly harmful to human health. XRD (X-ray diffraction) analysis was also performed to determine the type of minerals in the samples. Results and Discussion Studies show that dust events mostly affect the region in spring and summer. The rose of Sarakhs shows that the prevailing wind blows from the northwest all year round and the highest wind speed is related to summer. In Taybad, the prevailing wind blows from the northeast in spring, and in summer, the prevailing wind is northeast, but the north wind also has a considerable amount, both of which are faster than 11 m/s. Due to the fact that the prevailing winds in the region and the wind speed are the highest in summer, it is expected that dustier days will occur in summer. The results of the HYSPLIT model show that most of the particles transferred from Turkmenistan and a small part from Uzbekistan have moved to Sarakhs. Due to the altitude-based particle transport route, which is the lowest in Turkmenistan and reaches zero, it is likely that dust particles have moved from this loaded area to Sarakhs.  During the chemical analysis of the dust samples collected in Sarakhs and Taybad regions, nine main elements were identified. Comparison of the six main elements SiO2, CaO, Al2O3, Fe2O3, MgO and K2O with the study area with Sistan, Khuzestan, Iraq and the global average shows that the amount of quartz mineral in Iranian dust is less than the global average and the amount of Al2O3 is almost average. The world is equal but higher than other regions and the global average CaO is lower than the regions mentioned in Iran and Iraq. Based on the results of XRD analysis, nine minerals were identified in the dust samples that quartz, calcite, dolomite and montmorillonite had a higher percentage than other minerals among the studied samples. Due to the prevailing northeast wind direction, Hysplit model outputs and the presence of clay deserts in the north of Sarakhs in Turkmenistan, the presence of clay minerals in this region can originate from the upstream regions in Turkmenistan. Conclusion An elevation study of the particle motion path in the sampling interval based on the HYSPLIT model expenditures indicates that wind-transported particles may have entered the study area from Turkmenistan and a small part of Uzbekistan. The elements in the dust of the study area in comparison with the global dust show that CaO is almost twice the global percentage and other oxides correspond almost to the global percentages. The elements in Taybad samples are more than ferns and also the amount of elements in sediment samples is more than the passage which shows the efficiency of most of these samples in the region. The mineral composition of dust particles indicates that the minerals that make up most of the samples include quartz, clay minerals, and calcite. Mineralogical similarity between Central Asia, Northeast of Iran and Sistan with respect to the direction of dust movement in the direction of the prevailing wind and according to the Hysplit model indicates the movement of particles from Central Asia to the south to the Sistan region. According to the test results, the amount of lead, copper and manganese is more than the allowable limit and affects the health of residents in the area.}, keywords = {Dust,Chemical properties,XRD,Health,Northeast}, title_fa = {بررسی خصوصیات شیمیایی و کانی شناسی گرد و غبار ورودی به شمال شرق ایران و پتانسیل بیماری زایی آن}, abstract_fa = { پدیده گرد و غبار یکی از مهم­ترین مخاطرات طبیعی جهان بخصوص در حاشیه بیابان­ها و اقلیم خشک و نیمه خشک است. در فصل تابستان، طوفان‌های گرد و غبار ناشی از وزش بادهای صدو بیست که از بیابان قره‌قوم در جنوب ترکمنستان و بعضاً بستر خشک دریاچه آرال سرچشمه می­گیرند، بخش شمال شرقی ایران را تحت تأثیر قرار می‌دهند و شرایط زیست ساکنان این مناطق را به مخاطره می‌اندازند. به‌منظور درک تأثیر گردوغبار بر سلامت، خصوصیات شیمیایی گردوغبار ورودی به این مناطق مورد بررسی قرارگرفته است. بدین منظور اقدام به نصب نمونه بردار در مرز ایران و ترکمنستان (سرخس) و ایران و افغانستان (تایباد) گردید و نمونه برداری از تیر تا مهرماه 1396 به صورت ماهانه انجام گرفت و خصوصیات کانی‌شناسی و شیمیایی گرد و غبار با استفاده از روش‌های ICP و XRD انجام گرفت. نتایج نشان داد که در بین عناصر اصلی کلسیم، آلومینیم و سیلیسیم به ترتیب درصد بیشتری داشته و مقدار قابل توجهی از عناصر کمیاب B، S، Ba و Sr نسبت به دیگر عناصر در منطقه وجود دارند. کانی­های کوارتز، کلسیت، دولومیت و مونت­موریلونیت درصد بیشتری را نسبت به کانی­های دیگر در بین نمونه­های مورد مطالعه به خود اختصاص داده­اند. وجود عناصر سنگین نظیر آرسنیک، سرب، تنگستن، کادمیوم وآهن در نمونه­های گرد و غبار در غلظت­های بالا احتمال بروز سینوزیت، برونشیت، آسم و آلرژی و صدمه به عملکرد دفاعی ماکروفاژها که منجر به افزایش عفونت­های بیمارستانی می­گردد را افزایش می­دهد.}, keywords_fa = {گرد و غبار,شمال شرق ایران,سرخس,خصوصیات شیمیایی,سلامت,XRD}, url = {https://geoeh.um.ac.ir/article_34018.html}, eprint = {https://geoeh.um.ac.ir/article_34018_fb5ab43e901e8bf8b4fd181c12033c03.pdf} } @article { author = {Mohseni, Amir and Mohseni, Neda and Hosseinzadeh, Seyed Reza}, title = {Impact of Anthropogenic Activities on Environmental Hazards Caused by Heavy Metal Pollution in Agricultural Ecosystems}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {155-167}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v9i2.88703}, abstract = {Introduction Environmental pollution is one of the most contributing factors to the degradation of the biosphere quality and its components. Among these, heavy metals play an important role in human health. Metals can be divided into two categories in terms of plant nutrition. The first category includes some metals such as copper (Cu), nickel (Ni), selenium (Se) and zinc (Zn) that are essential in low concentrations for the health, growth, and production of microorganisms, plants, animals, and humans. Other groups of metals such as lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg) are not essential metals and may cause toxicity in plants and animals even in low concentrations. Soil contamination with heavy metals has become a global concern due to its threats to ecosystems including soil, water, plants, animals, and human life. Soil contamination by excess metals occur primary as a result of industrial activities such as metallurgical processes, mining, and sewage sludge application to agricultural land. In Iran, as the result of development of urbanization and industrialization, there is considerable concern about soil contamination by heavy metals. Zanjan province is one of the most industrialized cities in Iran due to having many heavy metal mines. One such heavy metal contaminated area is in the vicinities of the mining site of Zanjan Zinc Industrial Complex, Zanjan, Iran, where significant metal contamination of agricultural soils has been identified. Mining waste generated by mines and smelting units in this area is spread by wind or runoff to other areas and thus pollutes the soil, plants, surfaces, and groundwater. Crops grown in polluted areas are contaminated directly through the roots and indirectly through atmospheric subsidence. It has also been reported that agricultural products in Zanjan province are heavily contaminated with heavy metals in some areas and these metals can enter the food chain and thus affect human and animal health. The potential health risk from consumption of crops is assessed by hazard quotient (HQ). The safe range of HQ is values less than one. When the quotient is <1, this means no potential health effects are expected from exposure, but when it is >1, it signifies that there are potential health risks due to exposure. Despite the existence of many mines in Zanjan province, a comprehensive study on the potential health risks of consumption of grain crops has not been done, so the aim of this study was to investigate the changes in the concentrations of lead (Pb), cadmium (Cd), copper (Cu) and zinc (Zn) in wheat grains and soils at selected distances from a heavy metal pollution source (the mining site of Zanjan Zinc Industrial Complex, Zanjan, Iran) as well as the potential hazard quotient (HQ) related to these metals through the consumption of the product. Materials and Methods This descriptive cross-sectional study was performed on soil and wheat randomly selected samples located around the zinc mines in Zanjan; so that the samples could indicate the distribution of Pb, Cd, Cu and Zn in the area. Ten samples of wheat plants were harvested randomly from a radius of 10 to 40 km (10 (S1), 20 (S2), 30 (S3) and 40 (S4) km) from the mine during the harvest season. After separating the plant grain from other parts, the samples were placed in the oven for 24 hours at 100 ° C. Then plant extracts were extracted using digestion with 65% nitric acid and the concentrations of Pb, Cd, Cu and Zn were analyzed using atomic absorption spectrometry (AAS). Also, in order to study the changes in the concentrations of the soil metals at the selected distances from the mine, 3 soil samples were taken from a depth of 0-20 cm at any specified distance from the mine (S1, S2, S3 and S4). After air drying and sieving the soil samples, Pb, Cu, Zn and Cd available and total concentrations in the studied samples were extracted by DTPA-TEA and 4M nitric acid method, respectively, and then analyzed by AAS. Results and Discussion The results showed that distancing from the mine, the total and available concentrations of all four metals significantly decreased. The highest total concentrations of Pb (168.9 mg kg-1), Cd (5.6 mg kg-1), Zn (434.5 mg kg-1) and Cu (97.6 mg kg-1) were obtained from the S1 soil. The lowest total concentrations of these metals were recorded in S4 soil and equal to 59.1, 1.1, 88.5 and 28.9 mg kg-1, respectively. The available concentrations of all four metals were also decreased with increasing distance from the mine so that the highest concentrations of available Pb (45.6 mg kg-1), Cd (1.7 mg kg-1), Zn (52.4 mg kg-1) and Cu (24.8 mg kg-1) were obtained from the S1 soil. The lowest available concentrations of these metals were recorded in S4 soil and equal to 9.6, 0.2, 14.3 and 1.9 mg kg-1, respectively. However, no significant difference was observed between the available Pb concentration of soils taken from S3 soil and S4 soil. The comparison results of the mean Pb, Cd, Cu and Zn concentrations in wheat grains harvested from the soils around the mine showed that Pb, Cd, Zn and Cu concentrations in grain decreased with increasing distance from the mine. The highest concentrations of Pb (59.3 mg kg-1), Cd (1.3 mg kg-1), Zn (79.7 mg kg-1) and Cu (48.8 mg kg-1) were obtained from the grain samples harvested from S1 soil, followed by grains harvested from S2, S3 and S4 soils. Also, unlike Zn, Cu and Cd, no significant difference was observed in the Pb concentrations of grain samples harvested from S3 and S4 soils, which can be due to the non-significant reduction of the available concentration of Pb in the soil of S4 compared to S3 soil. Comparison results of hazard quotients ​​(HQ) revealed that the HQ amounts of all four metals were significantly decreased with increasing distance from the mine. The HQ levels of each metals at all distances from the mine are below one (with the exception of Pb), which indicates that the possibility of exposure to non-cancerous diseases caused by that metals will not be present for the consumer throughout life. If the HQ value of metal is greater than one, the toxicity of that metal may adversely affect the health of the consumer. Therefore, Pb has such a property and the HQ values of this metals in the distances of 10 (6.17), 20 (5.35), 30 (3.48) and 40 (3.31) km from the mine are high and dangerous. Conclusion  It is concluded that the consumers of these products will not be in the safe range in terms of the adverse effects of non-cancerous diseases caused by high concentrations of Pb. Moreover, despite the low HQ amounts of Zn, Cu and Cd, it is likely that the amounts of HQ increase in the coming years, especially for Cd and Cu. Therefore, much attention should be paid to consumption and cultivation around industrial areas.  }, keywords = {Hazard Quotient,Heavy metal,Environmental Hazard,Agricultural Ecosystem}, title_fa = {اثر فعالیت‌های آنتروپوژنیک بر مخاطرات زیست‌محیطی ناشی از آلودگی فلزات سنگین در اکوسیستم های کشاورزی}, abstract_fa = {آلودگی­های زیست‌محیطی از مهم­ترین عوامل مؤثر بر تخریـب و تنزل کیفیت بیوسفر و اجزای آن محسوب شده و در ایـن میـان فلزات سنگین از دیدگاه‌های زیستی، اکولوژیکی و سلامتی بشـر از اهمیت ویژه­ای برخوردارند. این پژوهش با هدف بررسی روند تغییرات غلظت عناصر سرب، کادمیوم، مس و روی در خاک­های تحت کشت اطراف معدن سرب و روی زنجان و همچنین احتمال خطرپذیری (HQ) به بیماری­های مرتبط با این عناصر از طریق مصرف محصول مورد نظر صورت پذیرفت. بدین منظور 4 فاصله مکانی مختلف انتخاب (10، 20، 30 و 40 کیلومتر فاصله از معدن) و از هر محدوده 3 نمونه خاک و 10 نمونه گیاه گندم برداشت شد. عصاره­های نمونه­های خاک با استفاده از DTPA و اسید نیتریک 4 مولار و عصاره­های گیاه با استفاده از اسید نیتریک 65% استخراج و غلظت فلزات با دستگاه جذب اتمی اندازه­گیری شد. نتایج نشان داد غلطت کل و قابل دسترس هر چهار عنصر در خاک و همچنین غلظت این عناصر در دانه گندم با افزایش فاصله از معدن کاهش یافت. بیش‌ترین غلظت سرب (3/59 میلی­گرم بر کیلوگرم)، کادمیوم (3/1 میلی­گرم بر کیلوگرم)، مس (8/48 میلی­گرم بر کیلوگرم) و روی (7/79 میلی­گرم بر کیلوگرم) از دانه برداشت شده از فواصل 10 کیلومتری از معدن و کمترین غلظت این عناصر از دانه برداشت شده از فاصله 40 کیلومتری از معدن و به ترتیب برابر 8/31، 2/0، 7/2 و 2/37 میلی­گرم بر کیلوگرم به دست آمد. نتایج احتمال خطر­پذیری به بیماری­های غیرسرطانی برای هر یک از عناصر با فاصله از معدن نشان داد که مقادیر احتمال خطر­پذیری به بیماری­ برای عناصر سرب، کادمیوم، مس و روی با افزایش فاصله از معدن کاهش یافت. همچنین به استثناء عنصر سرب، مقادیر خطر­پذیری در هر چهار منطقه مورد مطالعه کمتر از 1 بود. این نتایج نشان­دهنده این است مصرف‌کنندگان این محصولات در محدوده امن از نظر تأثیرات سوء بیماری‌های غیرسرطانی ناشی از غلظت بالای سرب قرار نخواهند گرفت. همچنین علی­رغم پایین بودن مقادیر HQ عناصر روی، مس و کادمیوم، احتمال افزایش این مقادیر در سال­های آتی برای این عناصر، به­ویژه عناصر کادمیوم و مس وجود خواهد داشت؛ بنابراین می­بایست توجه زیادی به مصرف و کشت در اطراف مناطق صنعتی، صورت گیرد.}, keywords_fa = {ضریب خطر,فلز سنگین,مخاطره زیست محیطی,اکوسیستم های کشاورزی}, url = {https://geoeh.um.ac.ir/article_34030.html}, eprint = {https://geoeh.um.ac.ir/article_34030_53d2b6df49dac9813556622c3b2acfcf.pdf} } @article { author = {Hossein Abadi, Saeed and Akbari, Ebrahim and Naghdbishi, Afsaneh}, title = {Evaluation and Simulation of Land Use Change Using Object-oriented Classification and Markov Chain Model, Case Study: Birjand City}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {169-188}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v0i0.81819}, abstract = {Introduction The global expansion of urbanization has created a motive for turning green and natural spaces into urban or human environments. On the one hand, increasing demand for land and housing, and on the other hand, limitation of land within cities, are pushing residents to find alternative housing in the surrounding areas. This process leads to increasing conversion and change of land cover and land use in the periphery of cities. Land use change is a process by which human activities transform the natural landscape and usually refers to the functional role of land for economic activities. This change of use can take place in the agricultural lands and orchards, or the ranges and forests and the slopes of mountains and hills. Therefore, one of the environmental hazards and ecological crises that the world faces is the phenomenon of land use change. Given the importance of the land use change process, it is necessary to estimate the rate and extent of land use or land cover changes in the region and the main drivers of these changes. Geographic Information Systems (GIS) and remote sensing techniques provide effective tools in studying and monitoring land use change / land cover in space and time. In general, the classification of satellite data refers to the separation of similar spectral sets and their classification. In other words, it expresses the classification of pixels constituting images, assigning or introducing each pixel to a class or a particular phenomenon. Object-oriented method is one of the methods of classifying images. In object-oriented classification, in addition to spectral features, geometric features of phenomena are also considered. In this way, object-oriented classification is a process that links land cover classes to visual objects. After the classification process, each image object is assigned to one (or none) of the class. In this research, it has been tried to analyze the land use change of Birjand city using two models of object-oriented classification and Markov chain model and to predict its trend for 2025. 2. Study Area Birjand is a city in eastern Iran and the center of Birjand city and the capital of South Khorasan province. The city is located at 59 degrees and 13 minutes of longitude and 32 degrees and 53 minutes of latitude and at an altitude of 1470 meters above sea level. According to Population and Housing Censuses of Iran in 2016, the population of this city was about 203,000 people and it is a city with relatively high and physical and population growth in the east of the country. Materials and Methods In this research, the land use changes in Birjand city were evaluated and simulated using satellite imagery images from 2000 to 2017 and predicted their changes by 2025. For this purpose, the object-oriented classification method has been used to classify the images. In this classification, for segment generation, the scale parameter is 10, the color parameter is 0.8, and the compression is 0.1 and shape is considered 0.4. In order to increase the resolution of classification classes for each class, further classes were created that merged with the main classes at the end. The final result is the segmentation of 4 general classes including vacant land, rangelands, built-up area, orchards and agriculture lands. After the classification of images, the CA-Markov model was used to predict of land use changes in the Birjand city. Results and Discussion According to satellite images, in 2010 compared to 2000, the built-up areas have been stretched discontinuously to the north and northeast direction of Birjand city, as well as to the west and to some extent to the east, which indicates that the physical growth of the city follows the pattern of sprawl in this period. The results of the classification of images in this study show that the area of ​​built—up lands  and the orchards and agricultural lands increased during the period between 2000, 2010 and 2017, and this increase is more significant between 2010 and 2017. The pattern of change has been such that the share of vacant lands and rangeland has been reduced. During the 17-year period, 0.48% of the area of rangelands and 0.38% of vacant land have been reduced annually. In contrast, the largest increase is related to built-up area, so that 6.12% has been added to this land use annually. Orchards and agricultural lands have also increased in area with a growth rate of 2.61% per year. According to the Markov chain model, the changes in the area of land uses in 2025 compared to 2017 will be similar to 2000-2017, so that orchards and agricultural lands (1.09), built-up areas (1.17), vacant lands (0.98), rangelands (0.97) will be. Conclusion In the present study, using satellite images during the period from 2000 to 2017, changes in land use of orchards and agricultural land, built-up areas and rangelands were investigated. In order to evaluate these changes, the object-oriented classification method in Ecogonation software was used and to predict and simulate the future, Markov chain method was used. Using the Markov chain model, the pattern of land use change for 2025 was predicted and modeled. The model consists of three steps: 1. calculating the conversion probabilities by using Markov chain analysis. 2. Calculating suitability of land use/land cover maps based on the multi-criteria evaluation. 3. The allocation of the land cover based on the CA's spatial operator. Based on the changes made in previous years, this model examines the probability of future changes and the spatial allocation of these changes. According to the Markov chain model, during the years 2000 to 2017, the area of the built-up lands, agriculture and orchards increased and the area of vacant lands and range decreased. If the same trend continues, between 2017 and 2025, the area of the built-up area will increase by 17.13%, orchards and agricultural lands by 9.8%, and in contrast, the area of vacant lands will decrease by 1.81% and the area of rangelands will decrease by 2.32%. In general, this pattern of land use change indicates an increase in human intervention and the dominance of human landscapes (settlements, orchards and agricultural lands) over the natural environment (especially rangelands). The next point that can be understood from the comparison of the maps is the development and sprawl growth of the settlements, which causes a part of rangeland and even agriculture and orchards to be changed to use for construction. In general, this abnormal trend of land use change should be controlled with a systemic approach to the study area, taking into account urban-rural, environmental and socio-economic dimensions in planning. This means that the change of use of good agricultural lands, orchards and rangelands must be controlled. This means that the change of use of good agricultural lands, orchards and rangelands must be controlled. One of the most important measures that can be considered is to follow the pattern of compact and urban infill growth with a focus on the use of urban brownfields and eroded texture.}, keywords = {Land use change,Object-Oriented Classification,Markov chain,Birjand}, title_fa = {ارزیابی و شبیه‌سازی تغییرات کاربری اراضی با استفاده از طبقه‌بندی شی گرا و مدل زنجیره مارکوف (مورد مطالعه: شهر بیرجند و پیرامون آن)}, abstract_fa = {برای استفاده بهینه از زمین، آگاهی از تغییرات کاربری اراضی و نوع استفاده از آن ضروری است؛ که این امر با ارزیابی و پیش‌بینی تغییرات کاربری اراضی امکان‌پذیر می‌گردد. مقاله حاضر به ارزیابی و شبیه‌سازی تغییرات کاربری اراضی شهر بیرجند با استفاده از تصاویر چندزمانه ماهواره‌ای در سال‌های 1379،1389 و 1396 و پیش‌بینی تغییرات آن‌ها تا سال 1404 پرداخته‌­است. تحقیق حاضر به لحاظ ماهیت توصیفی- تحلیلی و از نظر هدف کاربردی است. در این نوشتار با استفاده از تصاویر ماهواره‌ای لندست، سنجنده ETM و OLI و روش طبقه‌بندی شی‌گرا به طبقه‌بندی کاربری‌ها در بازه زمانی پرداخته­‌شده­است. در ادامه به‌منظور ارزیابی و پیش‌بینی تغییرات کاربری اراضی (محدوده‌های ساخته شده، باغات و اراضی کشاورزی، اراضی بایر و مراتع) از مدل زنجیره مارکوف استفاده ‌شده است. بر اساس مدل زنجیره مارکوف طی سال‌های 1379 تا 1396 مساحت محدوده ساخته‌شده، کشاورزی و باغات افزایش‌یافته است و از مساحت اراضی بایر و مراتع کاسته شده است. تغییرات مساحت کاربری‌ها در سال 1404 نسبت به 1396 نیز به همین صورت است. بیش‌ترین تغییرات مربوط به کاربری محدوده ساخته‌شده است؛ به‌طوری که تا سال 1404 مساحت محدوده ساخته شده 13/17 درصد، کاربری باغات و کشاورزی 8/9 درصد، افزایش و در مقابل مساحت اراضی بایر 81/1 درصد و مساحت مراتع 32/2 درصد کاهش خواهد یافت.}, keywords_fa = {تغییرات کاربری اراضی,طبقه‌بندی شی‌ءگرا,زنجیره مارکوف,توسعه کالبدی,بیرجند}, url = {https://geoeh.um.ac.ir/article_34046.html}, eprint = {https://geoeh.um.ac.ir/article_34046_3d7227e62ada1ea2a1e5e57a6840f6a8.pdf} } @article { author = {Ajza Shokouhi, Mohammad and Baghban, Sajedeh}, title = {Spatial Resilience Analysis in Mashhad Inefficient Texture Sites}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {189-213}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v0i0.82905}, abstract = {1. Introduction At the global level, there are significant changes in attitudes toward hazards, so that the dominant view has shifted from focusing solely on reducing vulnerability to increased resilience to disasters. Mashhad like many of the Iran's cities is in a high potential risk. Active and powerful faults in the vicinity of the city testify to the high risk of earthquakes in Mashhad. Moreover, there are seventeen rivers in and around the city of Mashhad that increases the risk of flooding in this city. Overall, the city is in a high-risk in upstream plans from a natural hazard perspective and the existence of 6688 hectares of inefficient texture (worn-out and marginal) in the city has added to its vulnerability. Although some predictive tools are effective in reducing the impact of crises, but based on evidence, future risks cannot be predicted; so it is necessary to know the resilience of city neighborhoods to avoid vulnerabilities. Resilience, however, is not a feature that is evenly distributed across different parts of the city, and it can be said that inefficient urban textures are less resilient than other parts of the city, largely due to their distinct social and physical characteristics. In addition to severe burnout and poor quality of buildings, low levels of social and demographic characteristics such as literacy, education, and employment that are effective in restoring urban neighborhoods, after a crisis lead to increased vulnerability to natural hazards. Therefore, this research was conducted with the aim of investigating the spatial resilience pattern in inefficient (worn-out and marginal) textures of Mashhad. 2. Study Area Mashhad is the capital of Khorasan Razavi province and situated in the northeast of Iran. This city is located at a longitude of 59 degrees and 2 minutes to 60 degrees and 38 minutes and a latitude of 35 degrees and 43 minutes to 37 degrees and 7 minutes between the Binaloud and Hezarmasjed Mountains. It is placed in a high-risk natural hazard zone. Mashhad has thirteen districts and 3057679 population. Of the 154 neighborhoods in Mashhad, all or part of 42 neighborhoods are inefficient. In general, about 6688 hectares of Mashhad are composed of inadequate (worn out and marginal) texture. 3. Material and Methods The present study was conducted with descriptive-analytical and practical methods. The indicators were extracted through library studies. Eventually, by using the opinion of experts in the framework of the Delphi method, required data were collected. Furthermore, some data were Extracted from Mashhad Master Plan (Farnahad, 2006), Statistical Yearbook of Mashhad (2016), and Road, Housing and Urban Development Research Center (2014), these indices are divided into social and social-physical divisions. Social indices only reflect social and demographic characteristics and socio-physical indices emphasize the physical characteristics and shape of neighborhoods in addition to demographic characteristics. The population consisted of 42 neighborhoods with inefficient texture in Mashhad. At first, using the MOORA technique, the social and socio-physical resilience of the inefficient neighborhoods was investigated. Then, the relationship between the distribution of resilience and social indicators using ArcGIS software was determined. In order to analyze the resiliency pattern, spatial self-dependency technique was used. There are different models for measuring spatial self-dependency statistics, among which the Global Moran Model and the  statistics have been used. Finally, in order to evaluate the accuracy and importance of geographic weight regression, the output of this model was evaluated. 4. Results and Discussion In order to calculate the resilience of each neighborhood, all data for each criterion were first standardized and evaluated using the MOORA technique. The findings show that the neighborhoods of Panjtan Al Abba, Shahid Avini, Hosseinabad, Ayatollah Khamenei, Valiasr and Abobargh have low social resilience, Imam Hadi neighborhood, Ivan, Torq, Mustafa Khomeini, Mohammadabad, Maaghoul, Arvand, Sajadiyyah, Onsory, Rezaei, Paien Khiaban, Dahdey, Amel, Sisabad and Bilal, have middle social resilience and the other are in the up social resilience of this category. Studding the social and socio- physical resilient spatial pattern of inefficient textures areas of Mashhad has been done by using the Global Moran method and general G statistics. Results show that the distribution pattern of these neighborhoods is clustering based on social resilience variables and is random based on socio-physical variables. In fact, there is statistically significant meaning in the social resilience of inefficient textures in Mashhad, On the other hand, this pattern does not exist in the socio-physical resilience. According to the Geographic weight regression, the variables of percentage of employed population, literacy rate and education level have an increasing effect on the level of social resilience of these neighborhoods, while the sponsorship rate and the mean age have a decreasing effect.   5. Conclusion Much of Iran's urban area is suffering from burnout and inefficiency, causing the country's capital to face the dangers of natural disasters. A review of the theoretical foundations and global experience shows that indices of identification of inefficient textures have moved from purely physical to social and economic dimensions. A review of the past researches about the resilience of urban inefficient textures showed that most studies like the research ahead, emphasize the impact of education indices and the percentage of the employed population on social resilience of societies, given that these indices are subject to socioeconomic conditions, this conclusion is justified. Studying the spatial pattern of socio-physical resilience in inefficient neighborhoods of Mashhad shows that the distribution pattern of these neighborhoods is clustered based on social resilience variables and randomly based on socio-physical resilience variables. In fact, there is a statistically significant pattern of spatial autocorrelation in the social resilience of Mashhad's inefficient textures, while this pattern does not exist in their socio-physical resilience. Since some of the inefficient textures of the city are being revived, it is not unexpected to compare these two patterns in the neighborhoods studied. More precisely, the inefficient textures revitalization in Mashhad has been occurred according to economic and managerial conditions of the neighborhoods, which has led to improvement of physical conditions and subsequently the improvement of the physical resilience while the social aspects of these neighborhoods have been neglected. In fact, the social aspects of development have been neglected in the development of dysfunctional textures. However, recognizing the social characteristics of each neighborhood as the smallest social unit of urban planning is particularly important in order to achieve sustainable development. The results of this study indicate that the inefficient neighborhoods in the city center and in the northern marginal areas of the city have a significant role in creating cluster patterns. In this regard, in order to increase the effectiveness of interventions, attention to the effectiveness of each of the variables in the targeting structure of interventions in this sector is necessary because the way these variables influence in different locations is different, and this should be considered in planning for inefficient textures regeneration. Overall, according to the findings of this study, it can be said that in the development of inefficient textures, paying attention to the social and demographic characteristics of each textures is important in promoting the quality of life of residents and the sustainable development of neighborhood. Moreover, it is necessary to pay attention to the differences in the strategies adopted with respect to the worn out and marginal textures. Because worn out and marginal textures each have unique and distinctive social, economic and physical characteristics, so attention and focus on these features are very important in their development process. This can partly indicate the type of intervention and its extent in the textures and guide the experts in selecting the type of intervention. In this regard, the following measures are suggested to increase the resilience of inefficient urban textures in the face of natural hazards: 1. Revising and changing management practices 2. Increasing the economic ability of people to improve their quality of life 3. Providing community decision-making and local partnerships in neighborhood improvement 4. Applying scientific methods and mathematical logic in identifying effective indicators and the degree of impact of indicators and prioritizing neighborhoods}, keywords = {Resilience,Inefficient texture,spatial dependence,Geographic weights regression,Mashhad}, title_fa = {تحلیل فضایی تاب‌آوری در محلات دارای بافت ناکارآمد شهر مشهد}, abstract_fa = {شهر مشهد در پهنه‌ای با میزان آسیب‌پذیری بالا قرار گرفته است که وجود 6688 هکتار بافت ناکارآمد (فرسوده و حاشیه) در این شهر، بر میزان این آسیب‌پذیری افزوده است. در این پژوهش، با رویکرد توصیفی_تحلیلی و با استفاده از روش‌های آمار فضایی (تکنیک خودهمبستگی فضایی و رگرسیون وزنی جغرافیایی)، الگوی تاب‌آوری در محلات دارای بافت ناکارآمد شهر مشهد مورد ارزیابی قرار گرفته و به مقایسۀ الگوی فضایی تاب‌آوری اجتماعی_کالبدی با الگوی فضایی تاب‌آوری‌اجتماعی پرداخته شده است. نتایج حاصل از کاربرد شاخص موران در توزیع فضایی تاب‌آوری اجتماعی، نشان می‌دهد که این ضریب مثبت و برابر 0.051 است. درواقع این مقدار، خوشه‌ای بودن توزیع فضایی تاب‌آوری اجتماعی در این محلات را نشان می‌دهد؛ در صورتی که این شاخص در مورد تاب‌آوری اجتماعی_کالبدی این محلات منفی و برابر0.03- است و نشان‌دهنده تصادفی بودن توزیع فضایی این عامل در محلات مورد مطالعه است و این مهم، بیانگر آن است که احیای بافت‌های ناکارآمد به صورت تصادفی و با توجه به شرایط اقتصادی، صورت گرفته و منجر به بهبود شرایط کالبدی این محلات گشته است، درحالی­که در بافت اجتماعی محلات تغییری ایجاد نشده است. تحلیل آماره G نشان می‌دهد که خوشه‌های  اجتماعی بالا در کنار یکدیگر قرار دارند و از الگوی خوشه‌ای با تمرکز بالا پیروی می‌کنند. خوشه‌های گرم و نسبتاً گرم حدود 30 درصد از محلات را شامل می‌شوند که 14 محله از شهر مشهد را تشکیل داده‌اند. همچنین مدل‌سازی عوامل مؤثر بر تاب‌آوری اجتماعی محلات دارای بافت ‌ناکارآمد شهر مشهد با استفاده از رگرسیون وزنی جغرافیایی نشان داد که متغیرهای نرخ باسوادی، سطح تحصیلات، درصد جمعیت شاغل، میانگین سنی و بار تکفل میزان تأثیرگذاری بیشتری بر تاب‌آوری محلات مورد مطالعه دارند. ازاین‌رو می‌توان این متغیرها را مبنای علمی برای افزایش تاب‌آوری اجتماعی این محلات در روند احیای آن‌ها دانست.}, keywords_fa = {تاب‌آوری,خودهمبستگی فضایی,رگرسیون وزنی جغرافیایی,مشهد,بافت ناکارآمد}, url = {https://geoeh.um.ac.ir/article_34059.html}, eprint = {https://geoeh.um.ac.ir/article_34059_4ea79b406a300416219639165dc80841.pdf} } @article { author = {Rahimi Herabadi, Saeed and Majidirad, Neda}, title = {Hermeneutics and Geomorphological Hazards; with Emphasis on Assessment and Zoning of Landslide Hazards in Rudbar Region}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {215-238}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v9i1.85783}, abstract = {Introduction The phenomenon of geomorphological hazards is due to the functional instability of the surface systems of the earth, which turn into hazardous events due to human intervention and human infrastructure. Meanwhile, cities, which are the densest human centers, may face some geomorphological hazards during their physical development. In mountainous areas, for example, the dangers posed by sloping processes cause the expansion of cities to face numerous bottlenecks. In general, urban geomorphological hazards in mountainous areas are studied in two main categories: first, hazards that are created in relation to the location of the city (i.e., being mountainous), and second, hazards that are due to the intensification of resource use and changes. Urban environments are created. In general, wherever the construction of a city on unstable land is planned, it is necessary to carefully study the conditions of the land and assess their relative risks. In this regard, identifying and zoning the risk of landslides, especially in settlements, is an important step in assessing the risk of this phenomenon. Landslide risk zoning includes the division of the land surface into separate areas and the ranking of these areas based on the actual degree or potential of landslides due to the occurrence of landslides on the slope. In this paper, the risks of urban landslides affecting urban development in Rudbar have been evaluated and zoned. In general, the purpose of such a study is the zoning of stable and unstable areas of Rudbar city, which can have favorable effects in its planning. However, what is necessary in completing the findings of this study is a deep understanding and hermeneutic interpretation like interaction of positive and post-positive methods which are used in this study in order to provide suitable conditions for further understanding of the models. Therefore, this paper tries to analyze the effective elements in the occurrence of domain hazards using network analysis process to quantitative analysis of stable and unstable areas, and then to qualitatively interpret the designated areas in order to apply the field and pay attention to geomorphological hazards in this city. Study Area Rudbar city, which is the central part of Rudbar city, is one of the foothill cities of Gilan province and is located on the banks of Sefidrood river in a mountainous area. The city is located in the geographical coordinates of 36 degrees and 32 minutes to 37 degrees and 7 minutes from the equator and 49 degrees and 11 minutes to 50 degrees 5 minutes east longitude. This city has an average height of 250 meters and is located mainly on the slopes overlooking the Sefidrood River. Material and Methods Methodologically, this paper has two parts: positive and post-positive; In the positive method, it is emphasized that the expected results can be achieved by pure statistical analysis. While in transcendental methods, understanding and its relation to other subjects, especially interdisciplinary studies, are given priority. In the positive part, in order to evaluate and zone the landslide hazards of Rudbar city, firstly, an attempt has been made to study the factors affecting the occurrence and intensification of landslides with emphasis on urban areas, especially in urban development issues of Rudbar. For this purpose, first, using the form and process method, the shape and process of the urban environmental control area of Rudbar was determined. In the next step, to prepare information layers, from the effective risk criteria obtained by field visits and library studies such as slope, altitude, land use, etc. from topographic maps 1: 25000 and 1: 50000 1: 100000 geological maps were used. In the next step, the effective information layers that were obtained with the opinion of experts and field and library studies were examined in the form of network analysis model. In this regard, to use the decision-making method of network analysis process in landslide assessment and zoning of Rudbar city, the following different steps were performed: 1- Determining criteria and indicators in identifying clusters and elements. 2- Determining the relationships and dependencies between the elements. 3- Applying the above connections in clusters and elements. 4- Weighting and pairwise comparisons of elements. 5- Classification and rating of information layers; Then, with the help of the meta-positive part, the obtained data and map were reviewed and interpreted based on the hermeneutic view. This means that these findings can be used for more in-depth analysis, better understanding and finally interdisciplinary findings of geomorphological hazards of Rudbar urban landslide to be more practical. Results and Discussion According to the final map obtained from the perspective of the positive method, it can be said that the control area of ​​urban areas in this area is in one of the most dangerous areas in terms of landslide risk so the current settlements and communication routes are mainly located in medium to high risk areas. On the other hand, the distances and privacy of urban centers, regardless of the processes and hazardous elements, are located and are on the path of physical development. In the future, the process of urban development of Rudbar will also expand in these areas. Therefore, paying attention to this issue and the environmental threats of urban areas is very important in planning the urban development model of Rudbar. From the point of view of meta-positive method and hermeneutic analysis, landslide phenomena can be studied and interpreted as a text from two points of view; One is in the form of written texts taken from statistical analyzes, and the second is in the form of map interpretation as an understanding of events governing low to high risk levels. Landslide phenomena as a text cover a wide range of numerical and statistical concepts that, with new references, new meanings of geomorphic reactions can be deduced because criteria such as slope, vegetation, average annual rainfall, land use, etc. in numerical language include general concepts that the author can discover and retell its meanings. This is also the case with landscaping maps. Altogether there are three distinct hermeneutic conceptual levels that include active (interpreted) or inactive (non-interpreted) text as well as active (non-landslide) or inactive (non-landslide risk expertise) minds to retrieve concepts and theories related to different trends. Geographical sciences were used in order to better understand the assessment and zoning of landslide hazards and their impact on the urban development of Rudbar. Conclusion In general, applied topics in geomorphological knowledge, especially geomorphological hazards, have strongly influenced researchers due to their mere entanglement in zoning models, statistics, the spirit of innovation, imagination and ideation. Therefore, relying solely on statistical methods and techniques and modeling causes the repetition of the position of this knowledge on issues such as zoning and landslide analysis, flood, wind erosion, etc.using network models, fuzzy. Which only emphasizes the relationship between precipitation, slope, vegetation, land use, etc., and it is necessary to provide more practical results with the facts of geomorphological hazards after quantitative studies and calculations, with the help of interpretation and hermeneutic studies. For this reason, it is less common for a researcher and expert in geomorphological hazards to provide systematic ideas in the field of management and environmental sustainability to reduce and adapt to hazards, etc., instead of resorting to statistics and software and analyzing the obtained outputs. In this study, an attempt was made to provide a more organized process for geomorphological risk management studies by providing case studies of different types of interpretations and by implementing hermeneutic levels and approaches in order to achieve more principled results. Because in the study of different levels of hermeneutics, the art of a geomorphologist is to convert passive texts into active text for the use and practical understanding of geomorphic phenomena in other fields and trends of geographical sciences such as urban and rural. Also, a geomorphologist in the framework of hermeneutic knowledge must have specialized perceptions of maps and diagrams that a non-expert cannot have a similar perception of. In this regard, with the aim of making the active text more practical, the interpretation of the landslide hazard  zoning map of Rudbar region was used and the findings of this knowledge were linked to the findings of other geographical sciences from the perspective of experts.}, keywords = {Geomorphological Hazards,Positive Methodology,Hermeneutic Interpretation,Urban Landslide,Environmental Management}, title_fa = {هرمنوتیک و مخاطرات ژئومورفولوژیک؛ با تأکید بر ارزیابی و پهنه‌بندی مخاطرات زمین لغزش در منطقه رودبار}, abstract_fa = {مباحث روش‌شناسی در مخاطرات ژئومورفولوژیک ازجمله ابزارهای علمی و فکری هستند که هیچ دانش‌پژوه جدی در این رشته نمی‌تواند، خود را از آنها معاف کند. به همین دلیل در این نوشتار به کمک دو نوع روش‌شناسی مبتنی بر روش ‌اثباتی (پهنه‌بندی درجات خطر با مدل تحلیل شبکه) و  فرا اثباتی (تفسیر هرمنوتیکی پهنه‌های خطر)، کوشش شده است، نتایج کمّی حاصل از مطالعه حاضر را با تفسیر و فهم نقشه به سمت کاربردی‌تر شدن سوق دهد. با توجه به وقوع زلزله‌‌ سال 1369رودبار و ناپایدارشدن دامنه‌های مشرف بر محیط‌ شهری رودبار و نیز کاربری‌های اراضی نامتجانس، وقوع زمین‌لغزش‌ در محیط شهری این منطقه به عاملی مخاطره‌آمیز‌ تبدیل شده است. این نوشتار‌ ‌تلاش دارد به ارزیابی و پهنه‌بندی حساسیت خطر زمین‌لغزش در سکونتگاه‌های منطقه رودبار بپردازد. به همین منظور با استفاده از فرایند تحلیل شبکه و تعیین معیارهای پیشنهادی مبتنی بر بازدیدهای‌میدانی و مطالعات کتابخانه‌ای‌ در وقوع خطر زمین لغزش شهری، این معیارها در دو خوشه‌ اصلی مخاطرات طبیعی و زیست‌محیطی طبقه‌بندی گردید. در مرحله‌ بعد با تهیه‌ لایه‌های اطلاعاتی از عناصر مزبور و ارزش‌گذاری آنها، این لایه‌ها در محیط ARCGIS مورد تحلیل قرار گرفت و نقشه‎ نهایی پهنه‌بندی خطر زمین لغزش در محدوده‌ کنترل کننده‌‌ رودبار با درجات خطر‌ کم‌ (4‌ درصد)، ‌متوسط ‌(‌71‌‌ درصد) و ‌بالا‌ (‌25درصد) تعیین گردید که نشان‌دهنده‌ تسلط فرایندهای مخاطره‌زا در محدوده‎ شهری است. در گام پایانی به منظور کاربردی نمودن و فهم عمیق یافته‌ها، نقشه خروجی در سطوح هرمنوتیک متن و ذهن فعال مورد تفسیر هرمنوتیک قرار گرفت. همچنین نمونه‌ای از تفسیر هرمنوتیکی از عینک دیگر صاحب‌نظران علوم جغرافیایی با هدف میان‌رشته‌ای شدن این خروجی مورد بررسی قرار گرفت. چنانچه هنر یک ژئومورفولوژیست، تبدیل نمودن متن‌های غیرفعال به فعال جهت استفاده کاربردی تحلیل‌های ناشی از پدیده‌های ژئومورفیک در سایر گرایش‌های علوم جغرافیایی نظیر مطالعات آب و هواشناسی، جغرافیای شهری، جغرافیای روستایی، جغرافیای سیاسی و... است.    }, keywords_fa = {مخاطرات ژئومورفولوژیک,روش‌شناسی اثباتی,تفسیر هرمنوتیکی,زمین لغزش شهری,مدیریت محیط}, url = {https://geoeh.um.ac.ir/article_34077.html}, eprint = {https://geoeh.um.ac.ir/article_34077_22ac294252e43391f449e9bd032d20f8.pdf} } @article { author = {Jafari, Gholam Hassan and Hazrati, Nasrin}, title = {Best Method in estimating the equilibrium-line altitude of late quaternary glaciers in Iran}, journal = {Journal of Geography and Environmental Hazards}, volume = {9}, number = {1}, pages = {239-262}, year = {2020}, publisher = {Ferdowsi University of Mashhad}, issn = {2322-1682}, eissn = {2383-3076}, doi = {10.22067/geo.v0i0.78427}, abstract = {1. Introduction Displacement of the equilibrium-line altitudes (ELAs) of Late Quaternary Glaciers in mountainous regions of Iran are mostly caused by climatic changes during Quaternary. It is vital to study surface landforms created by the inner and outer processes in this period (Yamani, 2007). Climate change in Quaternary has led to the emergence of glacial and inters glacial periods (Yamani, 2002). In Glaciology studies, the equilibrium line altitude (ELA) and the water and ice equilibrium line are the most important concepts (Ramesht et al. 2011). According to Porter (2005) “The equilibrium line is a place where snow accumulation is more dominant (Abtahi, 2013). Some national research examples are as follows: Evans (2006) in Wales, Sarikaya (2011) in Turkey, Mindrescu and Evans (2014) in Romania, Hendrickx et al. (2015) in Ethiopia, Jafari (2009), Moayeri et al. (2011) and Jafari (2014) in Iran. One of the most controversial issues in this regard is ELAs differences in different geographic latitudes and directions which is due to the variations along the slops which as a result made it difficult to discuss comprehensively. 2. Study Area Iran, with an area of 1648195 square kilometers, is located between 25 to 40 degrees north latitude and 44 to 63 degrees east longitude. Iran is divided into 6 geomorphic units (Zagros, North, Central Iran, East, Northeast and Northwest unit) (Alaei Taleghani, 2012). Iran is divided into 6 first and 30 second grade catchments (Water statistical yearbook of Iran, 2011). Of the 30 second grade catchments, Quaternary glacier cirques (6 morphotectonic units) were identified in 21 sub-basins. 3. Materials and Methods In order to estimate the ELAs, firstly an Iranian DEM with 30*30 meter resolution was prepared and merged and clipped for each basin. Merged topographic maps (1: 50000) were also extracted for each basin. Based on documents in topographic maps, 20-meter contour lines and the reflection of landforms in SRTM satellite images, cirques of each basin were identified. Secondly, according to the method of Terminus-to-Head Altitude Ratio (THAR), the identified cirques which didn’t have concave longitudinal profile were not considered in the estimations. Based on this, out of 30 second-grade catchments, 21 catchments were considered as basins that had been influenced by the glacial process in cool Quaternary spans. The ELAs were estimated using Porter’s cirque-floor altitude and Wright methods. The geographical directions of the cirques were classified into eight main and secondary directions. The ELAs were estimated using the following methods: 4. Results and Discussion In the present paper, 11641 cirques were identified in Iran based on the shape and height of the contour lines, status of the waterway network and the height of the peaks dominating in cirques. The surface slope direction affects the abundance of the cirques, meanwhile more than 60% of the cirques are formed in slopes that are inclined toward north in the whole country. Such slopes are known as Nesar slopes due to the inclination of the solar angle. After all the cirque were determined, the above methods were used to estimate ELAs. Comparison of the difference between the ELAs in different directions using Wright method revealed that the greatest difference was in salt lake (449 m) and Aras (440 m) catchments. The minimum elevation difference was observed in the Haraz-Gharehsu (-551 m) and Duranjir desert (-350 m) basins, and there were no differences in ELAs in different directions of three basins. Comparison of ELAs estimated by the cirque floor method in different directions indicates that Aras (761 m), Sefid-rud (602 m) and the central desert (350 m) basins had the greatest variations in different directions. In the morpho-tectonic unit of Central Iran, cirque-floor altitude and then the THAR methods (Wright) were more preferable, respectively considering the difference of estimated ELAs. 5. Conclusion The ELA in the Zagros morphotectonic unit was about 2608 m during the Quaternary. With further expansion in latitude, ELA differences in this unit, was estimated to be 637 m. The ELA of southwest slopes was estimated to be 524 m above the ELA of the northeast slopes. In total, ELAs were decreased from south to north during the Quaternary, so that the difference between Karun (the southernmost basin) and Aras catchments (the northernmost basin) was 484 m. From a longitudinal perspective, ELA differences is more than 800 m between the western catchment in the west (with an estimated ELA of 2300 m), and Duranjir catchment in the central Iran (with an altitude of 3100 m). In conclusion, during the Quaternary, the ∆ELA of Iran was more than 1065 m, and it varied between 2030 and 3100 m. The average ELA of Iran was about 2595 m. It can be concluded that in cirques landforms each latitudinal degree, could change the equilibrium-line altitude about 89 meters.}, keywords = {Quaternary,Iran,ELA,direction,cirque,Wright,Porter}, title_fa = {تجزیه و تحلیل روش‌های برآورد ارتفاع برف مرز دائمی یخچال‌های کواترنری در ایران}, abstract_fa = {تغییرات اقلیمی کواترنری موجب جابه‌جایی ارتفاع برف مرز در نواحی کوهستانی ایران شده است. با توجه به گستردگی ایران در عرض‌های جغرافیایی مختلف و امتداد متنوع ناهمواری‌های آن، بررسی تغییرات این ارتفاع به‌صورت یک واحد امکان‌پذیر نیست. بر این اساس در حوضه‌های آبریز درجه 2 ایران به تفکیک، آثار یخچال‌های کواترنری شناسایی شد. ارتفاع برف مرز به روش‌های رایت، ارتفاع کف سیرک پورتر، نسبت پنجه به دیواره رایت و پورتر و نسبت‌های ارتفاعی برآورد گردید. نتایج حاکی از آن است که ارتفاع برف مرز برآورد شده با روش رایت در بسیاری از حوضه‌های آبریز با روش‌های دیگر همخوانی ندارد. از اعمال این روش در برآورد ارتفاع برف مرز دائمی در چنین حوضه‌های آبریزی صرف‌نظر شد. در مجموع از 21 حوضه آبریز دارای آثار سیرک یخچالی کواترنری، ارتفاع برف مرز 9 حوضه آبریز با روش نسبت‌های ارتفاعی، 6 حوضه آبریز با روش ارتفاع کف سیرک پورتر، 5 حوضه آبریز با روش نسبت پنجه به دیواره رایت و 1 حوضه آبریز با روش نسبت پنجه به دیواره پورتر همخوانی بیشتری دارد. بالاترین ارتفاع برف مرز کواترنری برآورد شده، در حوضه آبریز کویر درانجیر در واحد ژئومورفیک ایران مرکزی 3098 متر و پایین‏ترین آن در حوضه آبریز تالش- مرداب انزلی در واحد ژئومورفیک شمال 2033 متر است. اختلاف ارتفاع برف مرز دائمی کواترنری ناهمواری‌های ایران، 1065 متر بوده است. این ارتفاع بین 2030 تا 3100 متر متغیر بوده است. در بین واحدهای ژئومورفیک بالاترین ارتفاع برف مرز کواترنری متعلق به ایران مرکزی (2853 متر) و پایین‌ترین آن در واحد ژئومورفیک شمال شرق (2424 متر) بوده است.}, keywords_fa = {کواترنری؛ ایران؛ برف مرز؛ جهت؛ سیرک؛,رایت؛ پورتر}, url = {https://geoeh.um.ac.ir/article_34095.html}, eprint = {https://geoeh.um.ac.ir/article_34095_dd33f41307000e132d82cc5422794a94.pdf} }