فهرست مطالب

  • پیاپی 27 (بهار 1394)
  • تاریخ انتشار: 1394/03/23
  • تعداد عناوین: 8
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  • معصومه رجبی، سمیه خسروی صفحات 1-12
    زمین سیستمی پویاست که تغییر و تحول از جمله ویژگی های آن است. نیروهای درونی زمین در قالب فرآیندهای نئوتکتونیک موجب تشکیل ناهمواری می شوند و لندفرم های اصلی را فراهم می آورند، به همین جهت ارزیابی و بررسی فرآیندهای تکتونیکی فعال و اثرات ناشی از آن ها از اهمیت بالایی برخوردار است. پدیده هایی که درنئوتکتونیک مطالعه می شود شامل تمام عوامل، فرایندها و عملکردهای ناشی از فعالیت های جدید زمین و اشکال ایجاد شده توسط این فعالیت ها است. پژوهش حاضر، بررسی فعالیت نئوتکتونیکی در حوضه آبریز قلعه چای است که شامل بخشی از ارتفاعات غربی کوه سهند می باشد. برای دستیابی به اهداف تحقیق، از شاخص های مورفومتری استفاده شده است که شامل: نسبت شکل حوضه زهکشی(BS) ، شاخص عدم تقارن حوضه زهکشی(Af)، نسبت پهنای کف دره به ارتفاع آن (Vf) و تراکم زهکشی(D)، می باشد که بر اساس محاسبات صورت گرفته BS 20/3 ، AF 27/39 و D میزان بالای تراکم و VF فعالیت زمین ساختی از نوع فعال را نشان می دهند که می توان حوضه ی قلعه چای را با فعالیت های تکتونیکی نسبتا فعال در نظر گرفت.
    کلیدواژگان: حرکتهای تکتونیکی، شاخصهای ژئومورفیک، دامنه ی شمال شرقی کوه کرکس، جبهه کوهستان و مخروط افکنه
  • ماریا محمدی زاده صفحه 13
    شناسایی و انتخاب مناطق مناسب اکوتوریسم در برنامه ریزی و مدیریت آن از اهمیت بالایی برخوردار است. مناطق خور خلاصی، جگین و کوئیک در شهرستان جاسک استان هرمزگان دارای قابلیت های فراوان از نظر اکولوژیکی و فرهنگی برای توسعه اکوتوریسم می باشند. در این پژوهش ابتدا با استفاده از روش دلفی و با همکاری 8 نفر از متخصصان مهمترین معیارها جهت توسعه اکوتوریسم انتخاب شدند. در این روش معیاره ای اقلیم، منابع آب، پوشش گیاهی، فاصله ازسکونتگاه های انسانی، آثار تاریخی فرهنگی، ارزش حفاظتی گونه های گیاهی و جانوری، نواحی زادآوری حیات وحش، امکانات زیر بنایی از میان 19 معیار پیشنهادی غربال و انتخاب شدند. سپس معیارهای غربال شده توسط متخصصانی که در روش دلفی همکاری داشتند، با استفاده از تکنیک آنتروپی شانون وزن دهی شدند. اولویت بندی مناطق جهت توسعه اکوتوریسم نیز توسط همان متخصصان و با استفاده از مدل تاپسیس انجام شد. براساس نتایج بدست آمده از مدل تاپسیس، منطقه خورخلاصی با نمره 0.7100، منطقه کوئیک با نمره 0.2920 و منطقه جگین با نمره 0.1183 بترتیب اولویت های اول، دوم و سوم جهت توسعه اکوتوریسم در شهرستان جاسک رتبه بندی شدند. نتایج پژوهش حاضر می توان متولیان طبیعت گردی کشور را در جهت انتخاب منطقه دارای اولویت سرمایه گذاری جهت توسعه طبیعت گردی در شهرستان جاسک یاری رساند.
    کلیدواژگان: اولویت بندی، اکوتوریسم، شهرستان جاسک، روش دلفی، مدل TOPSIS
  • طاهره فتح الله زاده صفحات 25-38
    حوضه های آبخیز در ایران از نظر زمین شناسی، ناهمواری و اقلیم و سایر عوامل موثر در امر فرسایش بسیار متفاوت هستند، هدف از این پژوهش بررسی انواع فرسایش در حوضه آبخیز ناورود، بررسی شدت فرسایش، تولید رسوب و عوامل موثر در این رابطه است در این خصوص ویژگی های فیزیوگرافی، توپوگرافی، اقلیمی، زمین شناسی، ژئومرفولوژی، پوشش گیاهی، خاک، فرسایش و تولید رسوب به طور کلی بررسی شد. این حوضه دارای مساحتی در حدود 265/46 کیلومتر مربع است. هدف کلی پژوهش، بررسی میزان فرسایش و تولید رسوب در حوضه و پی بردن به مناطق حساس از نظر فرسایش است. برای رسیدن به هدف فوق از روش پتانسیل فرسایش (ای پی ام) استفاده شده است. ابزارهای گردآوری اطلاعات، عکسهای هوایی، انواع نقشه ها، روش مشاهده و منابع کتابخانهای هستند. در این مطالعه با استفاده از روش ای پی ام میزان فرسایش در هر یک از زیر حوضه ها (زیر حوضه) بررسی شده است . در رابطه با ژئومرفولوژی منطقه از 22 نوع رخساره تشکیل شده است. با ادغام آنها با ساختار سنگ شناسی و مقاومت آنها در برابر فرسایش و تلفیق شیب به آنها 209 واحد کاری به دست آمد. بررسی شدت فرسایش و تولید رسوب در در هر واحدکاری با استفاده از روش تجربی EPM (کمی) صورت گرفت. براساس نتایج به دست آمده، زیر حوضه های شماره 4 و 5 از نظر شدت فرسایش بیشترین فرسایش را دارد (ضریب فرسایش 0/24 و 0/22). همچنین بیشترین رسوب زایی را نسبت به سایر زیر حوضه ها به خود اختصاص داده اند. علت زیاد بودن فرسایش ویژه و توان رسوب دهی دراین زیر حوضه ها، نسبت به زیر حوضه های دیگر شیب زیاد و حساسیت سنگ ها نسبت به فرسایش، تغییرکاربری، تخریب جنگل و مرتع، جاده سازی است.
    کلیدواژگان: فرسایش، حوضه ناورود، تولید رسوب، روش ای پی ام
  • سیاوش شایان، غلامرضا زارع، مجتبی یمانی، محمد شریفی نیا، محسن سلطان پور صفحات 39-56
  • صمد فتوحی، محمدرضا علیزاده، فاطمه اسلام فرد، مهدی جعفری صفحات 57-72
  • کمال امیدوار، معصومه نبوی زاده، میثم ثمره قاسم صفحات 73-90
  • علی محمدی ترکاشوند، رضا بیات، نصرالله مولایی هشتجین، سمیه جعفری صفحات 91-104
  • غلامرضا قهاری، امیر گندمکار، بهرام نجف پور، مسعود نجابت صفحات 105-118
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  • Masomeh Rajabi, Somayyeh Khosravi* Pages 1-12
    The Northeastern slope of Karkas Mountain is regarded as part of the Karkas mountain range which is located in south west of Natanz County and has spread along northwest-southeast directions. The study area has been placed in volcanic stretch of Urmia-Dokhtar (Tabriz-Bazman) area. Shrew and Schtoklin (quoted in Paroohan, 2001), have announced this area to be a broken and active axis with regards to volcanism (during upper Cretaceous-Eocene) and plutonic (Oligocene and Miocene).
    The main fault of the area is part of Qom-Zafreh fault being started from south west of Natanz and continues toward Zafreh. It is a right-lateral strike-out fault which has dug out quaternary alluviums in the northern Natanz.
    The displacement of water courses is usually right-oriented and the youngest fault is seen due to this mechanism in young alluvial fans of south west heights of Kashan.
    For the recognition of tectonic activities in the area under study we have used various geomorphologic indexes such as the mountain front congregation, length gradient of the river, the ration of valley bottom to its height and the morphometry of alluvial fans.
    Results obtained indicate that Northwestern slopes of the Karkas Mountains are still tectonically active.
    Keywords: Tectonic Movements, Geomorphic Indexes, Northwestern Slopes of Karkas Mountains, Mountain Front, Alluvial Fan
  • Maria Mohammadizadeh* Page 13
    Identification and selection of appropriate area is important for planning and management of ecotourism. Khalasi creek, Jageen and Queeck in Hormozgan province have great ecological and cultural potential for ecotourism development. In this research, first step Delphi method was used and in cooperation with eight experts the most important criteria in prioritizing of Khalasi creek, Jageen and Queeck was selected to develop ecotourism. In this method, climate, water resources, vegetation, human settelements distance, cultural monuments, the protection value of plant and animal species, wildlife breeding areas, infrastructural facilities were screened among 19 criteria.
    Then screening criteria using the Shannon entropy techniques were weighted by the experts who had cooperated in Delphi method.
    Prioritize areas for ecotourism development was performed as well as experts by using the TOPSIS model.Based on the results of TOPSIS model, Khalasi creek region with a score 0.7100, Queeck region with a score 0.2920 and Jageen region with a score of 0.1183 with order priority of the first, second and third were rated for ecotourism development in the city of Jask.
    Keywords: prioritization, Ecotourism, Jask province, Delphi method, TOPSIS Model
  • Tahereh Fatolazadeh* Pages 25-38
    Basins in terms of geology, climate and other factors on the roughness and erosion are very different, the aim of this study was to evaluate Navrood watershed erosion, erosion rate, sediment yield and factors in the relationship between the physiographic features, topography, climate, geology, geomorphology, vegetation, soil erosion is generally determined. The basin has an area of about 265/46 square kilometers. The aim of this study was to evaluate the erosion and sediment production in the watershed and to find the sensitive areas of erosion. To achieve the above objective, the erosion potential (EPM) was used for data collection. The data collection tools, aerial photos, map types, methods and library sources are observed. In this study, using EPM (Erosion Potential Method) erosion rate in each sub-basin (sub-basin 11) has been investigated. In relation to the regional geomorphologic outcrop s is composed of 15 types. By integrating them into the structure of the slope, lithology and resistance to wear and combine them work units respectively. The erosion rate and sediment production in each experimental work units using EPM (quantitative) took place. Based on the results obtained, the following basins 4 and 5 of erosion is most severe erosion (erosion rate of 0/24 and 0/22). The highest sediment than the other sub-basins have been allocated. Because of the large number of specific erosion and deposition in the sub-basin, sub-basin compared to other high slopes and rock sensitivity to erosion, Switch, grassland and forest degradation, road-building.
    Keywords: Erosion, Watershed Navrood, Sediment Production, EPM Method
  • Siavash Shayan*, Gholamreza Zare, Mojtaba Yamani, Mohammad Sharifinia, Mohsen Soltanpor Pages 39-56
    Deltas which are results of interaction between sea and land attracted interests of farmers and scientists, historically. Mond delta is one of landforms that located in Northern coasts of the Persian Gulf and in realms of Bushehr province. Different agents affected on formation, development and evolution of this delta, land and marine. In this research we tried to analysis and discuss effects of land dynamic main agents -basin morphology, sedimentation and tectonics- and basic factors such as climate, hydrology and human actions- on the formation and evolution of Mond delta. For achievement to research aims, we used of hydrologic, climatic data, geomorphologic parameters and quantitative methods. The result shows that expansion of basin and geotectonic activity in the Mond basin have significant role on formation of the delta. Basins’ rocks sensitive to erosion shows that weathering process is more, faster than normal and so produced more amount of sediment for transport to the Delta area. Basin slope in upstream has caused erosion and water to flow faster to outlet of basin ,and produced increasing rate of runoff, it caused reduction of infiltration rate and the flood flow. Climatic agents influence on the delta formation by ingredients of temperature (ice) and precipitation (rain showers), also hydrologic agents has significant role in depositing sediments, formation and evolution of Mond Delta by transportation of sediments. Human agent has significant effect on the delta evolution and reduction of sediment and discharge by construction of dam, during recent two decades.
  • Samad Fotohi*, Mohammadreza Alizadeh, Fatemeh Eslamfard, Mehdi Jafari Pages 57-72
    Geological phenomena and sights are among the most attractive tourist areas, which can be considered in geotourism as the vision of future economy. Geotourism is the sustainable form of nature-based tourism, which mainly focuses on experience and perception of nature and learning about it, is defined based on comprehensive and sustainable development, and is managed such that its resulting negative outcomes are few and its benefits are maximal for local societies, providing their welfare causes. Iran has a beautiful nature with climatic variety and regions full of unique geological phenomenon and the investigation of these attractions is necessary for gaining more knowledge about them. Mazandaran Province which owns beautiful landscapes, unique geomorphological phenomena, animal diversity, and vegetation is Iran's one of the most important tourism sources. Maintaining and preserving these valuable sources, especially unprecedented geological phenomena which are the result of millions of years of change and evolution of the earth in this region, require fundamental measures and planning at international and regional levels in order for this global legacy to be preserved based on principles of sustainable development and commitments of present generation to the generations to come. To this end, it is necessary to identify motivations of geotourists for visiting a natural attraction in order to present a planning for the protection of natural resources and tourism development. In this research, the selection motivation of geotourits for visiting Badab-e Soor region in Mazandaran Province is investigated. The research method was descriptive-analytical. In order to proximate the ranking to reality and obtain better results, a combination of correlation coefficient and AHP Delphi method which is called synthesis Delphi AHP correlation (SDAC) was used. Results showed that the most frequent motivation of tourists visiting Badab-e Soort geotourism region was its natural attractions.
    Keywords: Geotourism, Badab, e Soort, SDAC
  • Kamal Omidvar, Maasomeh Nabavizadeh*, Meysam Samarehghasem Pages 73-90
    Precipitation is one of important parameters of climatology and atmospheric science that have more importance in human life. recently, extensive flood and drought entered many damage to most parts of the world.
    Precipitation forecasting has important role in management and warning of this problem. Due to the interaction of various meteorological parameters in the calculation of rain, leads it to a very irregular and chaotic process.
    The purpose of this study, assessment of forecasting precipitation, using data from meteorological stations of the using common statistical period (2012-1989) in Kerman, Baft, Miandeh Jiroft.
    In this way, to the training of the artificial neural networks with structure Perceptron, Nonlinear Autoregressive External. Effective Factors in the rain, as input for Artificial Neural Networks and precipitation was considered as the output of the Network. Statistic indicators MSE, R were used for performance evaluation of the models.
    The analysis of output results from, Nonlinear Autoregressive External Neural Networks shown that these models have better accuracy and a high ability to forecast precipitation than Perceptron Neural Networks.
    The results showed the more exact method concerned to the (NARX) model. The 42 models with all parameters with Levenberg Marquat rule and sigmoid function had the best topology of the model in three stations. Overall, evaluation of NARX results showed that the errors of ANN were negligible. The NARX showed high sensitivity to relative humidity.
    Keywords: Precipitation Forecasting, Perceptron Neural Networks, Nonlinear Autoregressive External Neural Networks, Kerman, Baft, Miandeh Jiroft
  • Ali Mohammaditorkashvand*, Reza Bayat, Nasrollah Molaeehashtjin, Somayyeh Jafari Pages 91-104
    One of the main problems in the management of watersheds in the country is the lack of information and data. Due to the lack of Sediment Measurement stations in most country's watersheds and insufficient data, empirical models can be important tools for the preparation of these layers. EPM model is used in experimental models, the use of these models to estimate erosion and sediment in basins without data has the costs and difficulties in providing map. In EPM model, the user factor is one of the factors that can be provided through remote sensing with good accuracy and at lower costs. Tarik dam Basin in the west of Rudbar, Guilan province, was considered as study basin. The area of basin was 6102.1 ha with average elevation of 11296 m. Digital elevation model (DEM) from satellite SRTM radar were provided and the required maps were provided from DEM and satellite images. Land use map was prepared based on visual interpretation of Google Earth images and field views. The user factorof EPM model based on the conventional method (field views and corresponding table) and mean opinions of three experienced expert was appointed for each landuse unit. A number of indicators associated with a landuse such as NDVI, PVI, SAVI and MSAV were extracted on ETM satellite image in 2011. The average indices for every land use were calculated by Software of remote sensing, and by using a linear regression model, the relationship between the user factor and remote sensing indicators were analyzed. At the next stage, other factors of model based on traditional methods was carried out in determining and estimating of erosion. The erosion of basin was again estimated by using all previous factors and by more appropriate index. The best relationship between vegetation index (VI) and user factor of model was obtained that correlation coefficient was 0.793.
    Keywords: Erosion, EPM, Landuse, remote sensing
  • Gholamreza Ghahhari, Amir Gandomkar, Bahram Najafpor, Masoud Nejabat Pages 105-118
    Issue of climate change, global warming and the consequences tend to be the owners of the thoughts of statesmen and politicians around the world has attracted. To review the annual extreme temperature was used 42 years data from Shiraz synoptic station for the period 1971-2012. The global mean temperature anomalies data that ranged from 1990 to 2012 was used to examine the relationship between extreme temperatures and global warming. Statistical methods for linear regression and Man– Kendal were used for significant test for the trend of changes in the temperature series. Results indicate that despite the lack of long-term trend, after the onset of began the cold phenomenon, absolute minimum temperature gradient descending declining in Shiraz. Shiraz absolute annual maximum daily temperature is rising upward gradient, indicating a gradual increase in maximum temperatures and extreme heat of the summer.
    Keywords: climate change, Extreme temperature, Shiraz synoptic station, Man, Kendal test, linear regression