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فهرست مطالب طیبه بابایی اولم

  • موسی عابدینی*، امیرحسام پاسبان، طیبه بابایی اولم

    هدف از این پژوهش بررسی ارتباط بین تغییرات کاربری اراضی با دمای سطح زمین در شهرستان پارس آباد در استان اردبیل با استفاده از سامانه گوگل ارث انجین می باشد. در این راستا ابتدا در محیط برنامه نویسی گوگل ارث انجین با فراخوانی داده های ماهواره سنتینل 2 و سنتینل 1 نقشه کاربری اراضی شهرستان پارس آباد تهیه شد و در مرحله بعد جهت اعتبارسنجی با استفاده از ضریب کاپا میزان درستی و دقت کلی آن انجام شد. در گام بعدی در جهت بررسی آئروسل های شهرستان مورد مطالعه از داده های ماهواره سنتینل 5 استفاده شد و روند روزانه آن را با استفاده از روش رگرسیونی و چولگی طی بازه زمانی سال های (2018-2023) محاسبه شد. در گام بعد نقشه تراکم آلودگی شهرستان مورد مطالعه ترسیم و با فراخوانی داده های ماهواره MODIS اقدام به تهیه نقشه آنومالی دما و میانگین دمایی طی بازه زمانی سال های (2018-2023) شد و روند LST شب و نمودار نیم رخ جزیره حرارتی LST شب در بازه زمانی مذکور در ماه های تابستان (ژوئیه) با میانگین 297 کلوین و مقادیر حداقل در ماه های زمستان (ژانویه) با میانگین 270 کلوین مشاهده می شود. در نهایت با استخراج داده های نقشه های تراکم آئروسل های شهر با میانگین دمایی در محیط نرم افزار ArcMAP همبستگی بین این دو پدیده با روش رگرسیون خطی ساده پرداخته شد. نتایج نشان داد به جز بین این دو پدیده رابطه معکوسی بر قرار بوده است. هم چنین میزان آئروسل های روزانه از اواسط سال 2021 میلادی روند افزایشی به خود گرفته و چولگی منفی آن نشان از افزایش آلودگی ها در نواحی داخل شهری در سال های اخیر داشته است. نقشه تراکم آلودگی نیز نشان داد در نواحی داخل شهری و جاده های بین شهری مقدار آئروسل به صورت چشم گیری افزایش پیدا کرده است.

    کلید واژگان: تغییرات حرارت, کاربری اراضی, MODIS, پوشش گیاهی, شهرستان پارس آباد}
    Mousa Abedini *, Amirhesam Pasban, Tayebe Babaee Olam

     the purpose of this research is to investigate the relationship between land use changes and ground surface temperature in Parsabad city in Ardabil province using Google Earth Engine system. In this regard, the land use map of Parsabad city was prepared by calling the data of Sentinel 2 and Sentinel 1 satellites in the Google Earth Engine programming environment, and in the next step, its correctness and overall accuracy were validated using the Kappa coefficient. In the next step, the data of Sentinel 5 satellite was used to investigate the aerosols of the studied city, and its daily trend was calculated using the regression and skewness method during the period of 2023-2018. In the next step, the pollution density map of the studied city was drawn and by calling MODIS satellite data, temperature anomaly map and average temperature during the time period of (2018-2023) were prepared, and the night LST trend and the night LST thermal island profile chart in the mentioned time period In the summer months (July) with an average of 297 Kelvin, and minimum values are observed in the winter months (January) with an average of 270 Kelvin. Finally, by extracting the data of city aerosol density maps with average temperature in ArcMAP software environment, the correlation between these two phenomena was analyzed by simple linear regression method. The results showed that there was an inverse relationship between these two phenomena. Also, the amount of daily aerosols has been increasing since the middle of 2021 and its negative skewness has shown the increase of pollution in the inner city areas in recent years.

    Keywords: Temperature Changing, Land Use, MODIS, Vegetation, Parsabad City}
  • عقیل مددی*، طیبه بابایی اولم

    با توسعه روش های گوناگون در زمینه طبقه بندی تصاویر ماهواره ای و آشکارسازی تغییرات به ویژه در دهه های اخیر انتخاب بهترین و صحیح ترین روش برای تهیه نقشه کاربری و پوشش اراضی در مناطق مختلف رشد روزافزونی داشته است. هدف اصلی این پژوهش مقایسه دقت انواع روش های طبقه بندی برای تهیه نقشه کاربری اراضی در شهر رضوانشهر می باشد. بدین منظور هفت کلاس کاربری اراضی در شهر رضوانشهر (شامل مراتع، مناطق مسکونی، جاده، زمین های زراعی، رودخانه، مناطق ساحلی و جنگل) با استفاده از تصاویر ماهواره ای تعیین شدند. سپس نمونه های آموزشی از سطح منطقه با استفاده از تصاویر ماهواره ای، تصاویر گوگل ارث و بازدید میدانی جمع آوری شد. در مرحله بعد با استفاده از ویژگی های تصاویر کلاس های کاربری اراضی در محدوده مورد مطالعه تعیین و پس از مشخص نمودن میزان تفکیک پذیری کلاس ها طبقه بندی به صورت حداکثراحتمال (MLC)، ماشین بردار پشتیبان (SVM)، حداقل میانگین فاصله (MD) انجام شد. نتایج ارزیابی این سه روش نشان داد که روش ماشین بردار پشتیبان نسبت به روش های دیگر از دقت بیش تری (صحت کلی 60/92 ضریب کاپا 87/0 برای سال 2000 و صحت کلی 16/97 و ضریب کاپای 93/0 برای سال 2022) برخوردار است. بنابراین از نتایج این پژوهش می توان برای تهیه نقشه کاربری اراضی با دقت بالاتر با استفاده از روش ماشین بردار پشتیبان در کارهای ارزیابی محیط زیست و منابع طبیعی در مناطق با شرایط مشابه استفاده نمود.

    کلید واژگان: ماشین بردار پشتیبان, ضریب کاپا, نظارت شده, طبقه بندی, رضوانشهر}
    Aghil Madadi *, Tayebe Babaei Olam

    With the development of various methods in the field of classification of satellite images and the detection of changes, especially in recent decades, the selection of the best and most correct method for preparing land use and land cover maps in different regions has grown day by day. The main goal of this research is to compare the accuracy of various classification methods for preparing land use maps in Razvanshahr city. For this purpose, seven land use classes in Razvanshahr city (including pastures, residential areas, roads, agricultural lands, rivers, coastal areas and forests) were determined using satellite images. Then, educational samples were collected from the region using satellite images, Google Earth images and field visits. In the next step, by using the characteristics of the images, the land use classes in the study area were determined and after determining the resolution of the classes, the classification was done using maximum likelihood (MLC), support vector machine (SVM), and minimum mean distance (MD). The evaluation results of these three methods showed that the machine vector method has more accuracy than other methods (overall accuracy 92.60, kappa coefficient 0.87 for the year 2000 and overall accuracy 97.16 and kappa coefficient 0.93 for 2022). . Therefore, the results of this research can be used to prepare a land use map with higher accuracy by using the support vector method in environmental and natural resource assessment works in areas with similar conditions.

    Keywords: Support Vector Machine, Kappa coefficient, supervised, Classification, Razvanshahr}
  • پیش بینی تغییرات مورفولوژی رودخانه سفید رود با استفاده از Arc GIS
    عقیل مددی*، طیبه بابایی اولم، علیرضا قدرتی

    با توجه به رویدادهای سیل به ویژه برای سکونتگاه ها پیرامون رودخانه ها، عدم اطلاع صحیح از تغییرات متوالی بستر رودخانه و جابجایی آن در سال های آتی یکی از مسایل مهم علمی آبخیزداری می باشد از این رو به دلیل اطلاعات ناکافی از رفتار رودخانه ها، سکونتگاه های حاشیه رودخانه های مناطق ساحلی دایما دچار آسیب هستند. محدوده مورد بررسی این تتحقیق از مرز کنیک کوهستان تا جلگه می باشد. هدف از این پژوهش پیش بینی تغییرات مورفولوژی رودخانه (عرض کانال و اندازه گیری پیچانرودی و ضریب خمیدگی رودخانه) در مناطق ساحلی شمال کشور از طریق روش های تلفیقی سنجش از دور با مدل سلول های اتوماتیک وزنجیره مارکوف است. سفیدرود به عنوان بزرگترین و مهم ترین رودخانه سواحل جنوب دریای خزر نقش مهمی در زندگی، فعالیت ها و سرمایه های انسانی منطقه دارد. عوامل مورفولوژیک رودخانه و محیط های پیرامون آن و پیش بینی شرایط آینده می تواند در برنامه ریزی و آمایش دشت های ساحلی موثر و ضروری واقع شود. در این پژوهش از تصاویر ماهواره ای لندست 5، 7 و 8 سال های، 2002،1987 و 2018، همراه با داده های تغییرات تراز دریای خزر و دبی سفیدرود، بررسی های میدانی و نرم افزارهای Envi 5.3، ArcGIS 10.4.1 و Idrisi TerrSet به عنوان ابزار تحقیق بهره گرفته شد. ابتدا مقادیر احتمال تبدیل کاربری اراضی در سال 2018 بر مبنای مدل تلفیقی زنجیره مارکوف و سلول های خودکار به دست آمد. نتایج نشان داد که مدل تلفیقی، دارای دقت و صحت بالایی جهت پیش بینی الگوی آینده است. سپس با توجه به دقت و صحت خروجی مدل، نقشه پیش بینی کاربری اراضی و مورفولوژی رودخانه برای سال 2030 تهیه شد. با برازش دو نقشه سال 2018 و پیش بینی 2030 تغییرات محتمل در محیط رودخانه به دست آمد و در چهار محدوده مورد تحلیل قرار گرفت. در نهایت با استفاده از داده های تغییرات تراز دریای خزر و دبی سالانه رودخانه سفیدرود، روند تغییرات و پیش بینی مدل، مورد بررسی قرار گرفت. بیشترین احتمال تغییرات بر اثر تاسیسات ساخت انسان می باشد. فرایندهای فرسایشی، تغییر پیچانرودی و سیل گیری در حد فاصل سد سنگر تا روستای لومان بصورت جابجایی جانبی کانال و تشدید پیچانرودی، روستای کیسم و شهر آستانه اشرفیه و آزادسرا تا لیچاه بصورت سیل گیری تاسیسات انسانی و در محدوده کیاشهر، تالاب بوجاق و دلتای سفیدرود بصورت تغییر موقعیت مصب و جابجایی به غرب کانال رودخانه می باشد، با توجه به نتایج بررسی مقطع عرضی کانال رودخانه در سه دوره 1987، 2002 و 2018، روند کاهشی عرض کانال رخ داده است.

    کلید واژگان: زنجیره مارکف, سفیدرود, مدل سلول های اتوماتیک, مطالعات سنجش از دور}
    Forecasting Changes in the Morphology of Sefid Rood River Using Arc GIS
    Aghil Madadi*, Tayebeh Babaei olam, Alireza Ghodrati

    Considering the flood events, especially for the settlements around the rivers, the lack of correct information about the consecutive changes of the river bed and its movement in the coming years is one of the important scientific issues of watershed management, therefore, due to insufficient information about the behavior of the rivers, the settlements along the rivers in the coastal areas are constantly damaged. The scope of this research is from the border of Konik Kohestan to Jalga. The purpose of this research is to predict the changes in river morphology (channel width and measurement of Pichanroudi and river curvature coefficient) in the coastal areas of the north of the country through the integrated methods of remote sensing with the model of Markov automatic weighing cells. Sefidroud, as the largest and most important river on the southern shores of the Caspian Sea, plays an important role in the life, activities and human capital of the region. The morphological factors of the river and its surroundings and the prediction of future conditions can be effective and necessary in the planning and preparation of coastal plains. In this research, the Landsat 5, 7 and 8 satellite images of 2002, 1987 and 2018, along with the data of changes in the level of the Caspian Sea and Sefidroud Dubai, field surveys and Envi 5.3, ArcGIS 10.4.1 and Idrisi TerrSet software as The research tool was used. First, the probability values of land use conversion in 2018 were obtained based on the integrated model of the Markov chain and automatic cells. The results showed that the integrated model has high precision and accuracy to predict the future pattern. Then, according to the accuracy and accuracy of the model output, the prediction map of land use and river morphology for 2030 was prepared. By fitting the two maps of 2018 and the forecast of 2030, possible changes in the river environment were obtained and analyzed in four areas. Finally, using the data of changes in the level of the Caspian Sea and the annual discharge of the Sefidroud River, the trend of changes and prediction of the model was investigated. The most likely changes are due to man-made facilities. Erosion processes, change of Pichanroodi and flooding in the distance from Sangar Dam to Luman village as lateral displacement of the channel and intensification of Pichanroodi, Kisem village and the city of Astana Ashrafieh and Azadsara to Lichah as flooding of human facilities and in the area of Kiashahr, Bojag wetland and delta Sefidroud is changing the position of the estuary and moving to the west of the river channel, according to the results of the survey of the cross section of the river channel in the three periods of 1987, 2002 and 2018, there has been a decrease in the width of the channel.

    Keywords: Markov chain, automatic cell model, remote sensing studies, Sefidroud}
  • صیاد اصغری سراسکانرود*، طیبه بابایی اولم

    فرسایش خاک یک مشکل جهانی است که منابع آب و خاک را تهدید می کند و تغییرات کاربری اراضی یکی از عوامل مهم در فرسایش خاک است. هدف از این پژوهش ارزیابی و بررسی تاثیر تغییرات کاربری اراضی در یک دوره بیست سال بر میزان فرسایش و رسوب با استفاده از مدل RUSLE در حوضه آبخیز شفا رود در استان گیلان می باشد. به منظور اجرای این تحقیق ابتدا تصاویر ماهواره ای منطقه مورد مطالعه مربوط به سال های 1381 و 1401 و ماه خرداد از مرکز تحقیقات زمین شناسی آمریکا دریافت و پس از تصحیحات اتمسفری و رادیومتریک با استفاده از روش طبقه بندی نظارت شده به شیوه ماشین بردار پشتیبان اقدام به تهیه نقشه کاربری اراضی در هر دو سال شد. سپس به منظور برآورد میزان فرسایش در هر دوسال از مدل RUSLE استفاده شد. جهت تجزیه و تحلیل و تولید نقشه ها در اجرای این تحقیق نیز از نرم افزارهای Excel، ArcGIS 5.4، Archydro و ENVI 5.3 استفاده شد. نتایج این تحقیق نشان داد که در طول بیست سال اخیر کاربری های اراضی زراعی و مراتع در منطقه کاهش و در مقابل سطح مناطق مسکونی افزایش یافته است. هم چنین نتایج بررسی تغییرات فرسایش نشان داد میزان فرسایش از سال 1381 تا 1401 از 63/5 به 37/8 تن در هکتار در سال رسیده که روندی افزایشی داشته است.

    کلید واژگان: فرسایش خاک, ماشین بردار پشتیبان, RUSLE, شفا رود}
    Sayyad Asghari Saraskanrood *, Tayebe Babaei
    Introduction

    Soil erosion is a natural process that causes soil loss due to various environmental factors such as weather, soil, topography and vegetation (Obayat et al., 1400). However, human interventions through land use change and agricultural and construction activities can accelerate this flow (Wenker et al., 2019). For this reason, soil erosion caused by land use change has become the most important problem of land degradation all over the world, and the transformation of the land form and the disruption of the main functions of the ecosystem are the consequences of these geomorphic reactions. Therefore, the purpose of this research is to investigate the impact of land use changes in a period of twenty years on the amount of erosion and sedimentation in Shafa Roud basin.

    Methodology

    Shafarood watershed is between 48 degrees and 41 minutes to 49 degrees and 6 minutes and 30 seconds from the Greenwich meridian in the eastern hemisphere and between 37 degrees and 25 minutes to 37 degrees and 41 minutes and 30 seconds from the equator and in the northern hemisphere and in It is located in the west of Gilan province and Talash region. The highest peak of this basin called Sharaf in the northwest of the studied area is 2892 meters high, and its lowest point is about 71 meters above the surface of open water.In this research, the data of rain gauge stations nearby and inside the basin were used to analyze the rainfall data. It should be noted that the quality of the data used was checked before entering the statistical analysis stages, and after removing the possible statistical deficiencies and also checking the outliers of the data, it entered the statistical analysis stage. In the processing of satellite images, it is very important to choose the right time of the images taken to prepare the land use map, so in the present study, the multi-temporal images of the Landsat series in cloudless conditions (Bascula et al., 2017) in the middle of June 2011 and 1401 Shamsi (2004 and 2022 AD) was obtained through the United States Geological Survey (USGS) website. Considering the growing season of pasture plants and the timing of planting and harvesting crops, it seems that the images from mid-June are suitable for preparing land use maps. In this research, the information of all the spectral bands of the mentioned images was used for land use classification. Also, in this research, Excel, 5.4 Arc GIS, Archydo and ENVI 5.3 software were used to analyze data and prepare maps. In this research, the RUSLE model was used to estimate the annual average soil erosion. RUSLE model is a function of 6 input factors including rain erosion (R), soil erodibility (K), slope length and degree (LS), vegetation management (C) and conservation operations (P).

    Conclusion

    In this research, the supervised classification method and the support vector machine classification method, which has high accuracy, were used to monitor the changes that occurred during the 20-year period. The classification accuracy of both images was evaluated with the Kappa index and overall accuracy, and according to the research of Mather (2005), the results of the current research are statistically acceptable. Based on the results of the classification accuracy in the two images, the classification accuracy in the order of the date of receiving the image had an increasing trend, which is due to the up-to-date information of the region for the 2022 image and the possibility of direct access to the current land use in the region for selecting educational samples. It was natural. In addition, the accuracy obtained in both images is acceptable and shows the high ability of Landsat images to prepare land use maps with acceptable accuracy, which is in line with the research results (Sengari and Broumand, 2013; El Kawi et al., 2011). Correspond. Of course, it should be noted that the high accuracy of classification is not the only result of the implementation of the classification process, in addition to these cases, the collection of educational samples with appropriate distribution and number at the basin level has played a significant role in improving the classification process. In general, the accuracy of the results obtained from the two images had similar results for all applications, which can be attributed to the collection of suitable educational samples and the simultaneous date of the collection of the two images (June). The results of the survey of land use changes during 20 years in the region showed (Table 3), agricultural lands and pastures have decreased in the region. The reason for this can be related to the droughts of recent decades in the region and also the decrease in the level of underground water tables, which has reduced the amount of water available to farmers. This result is in line with the research results (Sultanian et al., 2013), but it is against the research results (Nazari Samani et al., 2006 and Rajesh and Yoji, 2006) that the agricultural land has decreased in a period, of course, It seems that the reduction of agricultural lands in his research was due to the increase of residential constructions in the agricultural lands of the region. On the other hand, the level of residential land in the region has increased, which seems natural due to the increase in population in the region and new construction in the villages. The obtained results show that the amount of erosion in 2011 varies from -0.84 to 5.63 tons per hectare per year and in 1401 from -1.33 to 8.37 tons per hectare per year. These results show that the amount of erosion in This basin has increased slightly in 20 years.The obtained results show that the amount of erosion in 2011 varies from -0.84 to 5.63 tons per hectare per year and in 1401 from -1.33 to 8.37 tons per hectare per year. These results show that the amount of erosion in This basin has increased slightly in 20 years.

    Keywords: Soil erosion, Support Vector Machine, RUSLE, Shafarood}
  • موسی عابدینی*، طیبه بابایی اولم، امیرحسام پاسبان

    مخاطرات طبیعی، بخشی از رفتار محیط است که در هر زمان و مکان احتمال رخداد آن وجود دارد. فراوانی، گستردگی و شدت این نوع مخاطرات در دهه های اخیر افزایش یافته است. آگاهی از رفتار مخاطرات طبیعی و شناخت کانون های رخداد آن ها برای برنامه ریزی محیطی و توسعه پایدار اقتصادی از اهمیت بالایی برخوردار است. حوضه آبریز ویرمونی در سال های اخیر دچار مخاطرات طبیعی از قبیل سیل و رانش زمین شده است که این مخاطرات در روند زندگی ساکنان مستقر در منطقه مشکلاتی را بوجود آورده است. در این تحقیق با استفاده از مطالعات میدانی و مصاحبه های حضوری با اهالی روستاهای مورد مطالعه و با استفاده از روش های تجربی و اطلاعات موجود کتابخانه ای و آماری تاثیر عواملی چون زمین شناسی، اقلیم، توپوگرافی، شیب، ژیومورفولوژی و پوشش گیاهی در ارتباط با مخاطرات محیطی حوضه آبریز ویرمونی مطالعه شده و نقشه پهنه بندی پتانسیل وقوع مخاطرات محیطی با استفاده از نرم افزار GIS تهیه شده است. بدین منظور از نقشه های توپوگرافی، نقشه های زمین شناسی و کاربری اراضی ، شیب و جهت شیب و آمار مربوط به ایستگاه های آب سنجی و داده های ثبت شده زلزله استان مورد مطالعه در 20 سال اخیر استفاده شد. بررسی مسایل مربوط به ژیومورفولوژی و زمین شناسی منطقه مشخص نمودند که اکثرا دامنه های حوضه شیب شان به جهت شرقی است و عمدتا در شیب های بین 15-30 درجه به دلیل غلبه با هوازدگی شیمیایی، رطوبت زیاد و مواد ریز و نرم سطحی (خاکهای ضخیم لایه)، پتانسیل وقوع حرکات دامنه ای (خصوصا زمین لغزش) بالاست.

    کلید واژگان: مخاطرات طبیعی, سیل, حرکات دامنه ای, پهنه بندی, ویرمونی}
    Mousa Abedini *, Tayebe Babaee Olam, Amirhesam Pasban
    Introduction

    Environmental hazards, both natural and human, are threatening and capable of harming the human physical and social environment. This damage not only occurs during the occurrence, but is also likely in the long term Environmental hazards are caused by three factors: nature, human and technology The increase in the world's population from three billion people in 1960 to 7.6 billion people a year and the possibility of its increase to 11 billion people in 2050 is one of the reasons for the pressure on nature and the occurrence of hazards Every year many natural hazards and disasters occur in our country, therefore, today it is time for the planners and policy makers of the society to accept that there are always strange events in nature and to predict the possibility of their occurrence in their plans and programs so that when they occur with the volume to face less problems. In other words, knowing the risks is important to reduce them, more important is that people and societies accept the reality of the existence of risks. The frequency and spread of calamities caused by natural hazards has increased In most cases, natural disasters cause severe financial and human losses and disrupt economic and social activities.

    Methodology

    Virmoni catchment area is located between 48°43° to 48°50° east longitude and 38°21° to 38° north latitude. This basin is one of the large sub-basins of Talash and rivers in the northwest of Gilan, which originates from the western heights of Astara city (Mount Espinas) at an altitude of 1300 meters and passes through the village of Laton and after passing through the villages of Laton , Turk Mahalle, Awad Ler, Sayadler, Jibreel Mahalle, Sheikh Mahalle, Amir Mahalle and Bijarbin closes at zero altitude near the village of Virmoni, and the branch continues past the middle of Astara city and finally empties its water flow into the Caspian Sea. do The studied basin is limited to Lundville basin from the south, Bezoune basin from the southeast, Caspian sea from the east, Astrachai and Azerbaijan Republic in the north, and Astrachai basin in the west. Its direction is first southwest-northeast and after the exit of the basin in the mountain (the place where the basin closes) it has a general west-east direction. The area of its small water basin at the point of entering the plain is 45 square kilometers, the length of its main branch is 13 kilometers and its shape is elongated, and the average annual volume of the river flow at the point of entering the plain is 28 and 47 million square meters at the Astara station. The water flow of this river has been under investigation and control since 1364, and its power source is the annual rainfall of the area in the rainy season and the melting of the snow in the highlands in the hot season. In (Figure 1) the geographical location of Virmoni watershed is presented.

    Discussion

    General Geology of Talash: This mountain range with a north-south (N-S) trend is basically an anticline, which has a north-south axis, the eastern slope has a steep slope and the western slope has a relatively gentle slope. The border of this mountain range with the Caspian sea basin is probably a fault (Astara fault). Talash mountain range is divided into two major parts under the main divisions of Tektunuk: Eastern zone and Western zone. It may be possible to imagine the Noor fault as the boundary of these two zones, as the deposits of the eastern part of the fault are mainly formed from a large amount of clastic sediments along with volcanic activities related to the Late Cretaceous and Paleocene times, and have created anticlines and transgressions in the north-south direction. In its core, in the area of Khutbah Sera, they have found a complex of metamorphosis. Therefore, the oldest rock unit includes metamorphic rocks belonging to the Precambrian, and formations belonging to the Jurassic and Cretaceous, such as limestone, sandy limestone, and pyroclastic rocks of the Cretaceous and Paleogene, including sandstone, conglomerate, gray shales, tuffs, andesitic flows. Agglomerate tuff and basalt and sand and silt sediments along with gypsum and salt layers are outcropped in the west of Astara. There are no limestones that can feed the underground water table of the plain in the region, and only in the headwaters of some rivers, there are Cretaceous limestone formations in the form of silty limestones and sand with many joints and cracks, which play an essential role in the formation of the river's base discharge.

    Conclusion

    The current research is under the title of zoning the potential of natural hazards in the Virmoni catchment basin, which during the past seasons has investigated the performance of various natural and human factors influencing the occurrence of natural hazards and the effect of these hazards on the environment and finally preparing a zoning map of the potential of occurrence. According to the results obtained in the topographic section, the area under study is located in the extreme north-west of Talash mountains, and it consists of two parts, the foothills and the plains, and the topographical factors that are effective in the mass movements of this area are the slope, direction and height. According to the studies conducted in the climate section, based on the climate coefficient calculated by Dumarten and Amberget methods for the selected station, this region is located in a very humid climate. In terms of rainfall, it is one of the regions that benefit from the highest rainfall in the country. The effects caused by this type of weather due to excessive rainfall have caused the soil of this region to increase the adhesion and adhesion of its particles and grains to each other, and the penetration of water due to heavy rainfall and increased water pressure has caused Slope movements, especially landslides in the slopes, and the occurrence of heavy rainfall for several days also cause floods. According to the vegetation department studies, the majority of the area is of dense forest vegetation type. This factor prevents landslides to a large extent despite the availability of other natural conditions, but in case of land use change, the conditions for landslides occur. Landslides occur after heavy and continuous rains. The geomorphological studies of the region show that, after the stabilization of the structural geomorphology of the region and the creation of the current complications at the beginning of the Quaternary, the dominant phenomenon in the region, apart from the change of the Caspian Sea bed level during the glacial and interglacial periods, is probably chemical weathering with great intensity. has been high Because considering the current climate (Astara synoptic station) where the rainfall is more than 1368 mm, the average annual temperature is 15.9 degrees Celsius, good conditions are provided for chemical weathering; Especially since the number of frosty days in the region is very few. The evidence in the region indicates that the region follows the Caspian system. According to the climatic information of Astara, based on Peltier's morphogenic model, the weathering system will be of medium chemical type with weak ice performance. In such a system, river morphogenesis is intense, mass movement is moderate, and wind morphogenesis is very weak. However, human intervention in changing the environment and manipulating the unevenness has accelerated the occurrence of the normal phenomena of geomorphology, i.e. the process of morphogenesis. In general, the most important results obtained in understanding the risk factors are as follows: The most important factor in the creation of fine surface materials and clays and silts is chemical erosion caused by rain on rocks. The rocks in which the most landslides have occurred are mostly volcanic igneous rocks with volcanic lava, cataglomera and shale with their surface materials such as clay, marl and silt. The lack of proper drainage of the underground waters that are located on the upper level and the infiltration of sewage water on top of some slopes, which increase the water pressure between the holes of the rocks and the surface materials of the slopes, cause an increase in the number of landslides and damages caused by it Will be Another cause of mass movements is the abandonment of agricultural terraces on the slopes in the foothills of the region. The lack of agricultural activity on them blocks the spaces between the stones and drainage is not done well, and in fact, heavy and consecutive rains, water accumulates and cannot penetrate, brings the range to the limit of plasticity and flow. Investigating issues related to the geomorphology and geology of the region revealed that most of the slopes of the basin slope towards the east. Mainly in the slopes between 15-30 degrees due to chemical erosion, abundance of water and fine and soft surface materials (thick-layered soils), the ground for potential and actual slope movements is high.

    Keywords: Natural hazards, Floods, range movements, Zoning, virmony}
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