فهرست مطالب

جغرافیا و پایداری محیط - پیاپی 16 (پاییز 1394)
  • پیاپی 16 (پاییز 1394)
  • تاریخ انتشار: 1394/09/20
  • تعداد عناوین: 7
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  • امجد ملکی، محمدحسین قبادی، پیمان کریمی سلطانی صفحه 1
    غار علیصدر در روستایی به همین نام در شهرستان کبودرآهنگ قرار گرفته است.این غار توریست پذیرترین غار کشور بوده و سالانه بیش از هشتصد هزار گردشگر داخلی و خارجی از آن دیدن می کنند.بازدید روزانه چندین هزار گردشگر از درون غار، به ویژه در نیمه اول سال و ایام پایانی هفته،سبب تغییراتی در مقادیر عناصر اقلیمی و دی اکسید کربن موجود در درون غار می شود.غلظت بالای دی اکسید کربن ناشی از بازدم گردشگران و رطوبت نسبی اشباع یا نزدیک به اشباع درون غار، به تدریج منجر به کاهش PH محیط و شکل گیری یک محیط اسیدی در درون غار شده وانحلال و پوسته پوسته شدن اشکال ثانویه درون غار را در پی دارد.از این رو،در این مقاله تلاش شده است تا با شبیه سازی و بازسازی شرایط اقلیمی درون غار در محیط آزمایشگاهی کنترل شده،مقدار انحلال سالانه اشکال ثانویه درون غار به تفکیک سهم گردشگران،به شیوه وزنی محاسبه گردد.برای این منظور،با تفکیک فضای درون غار به دو بخش آزمایش و کنترل، اقدام به جمع آوری داده های مربوط به مقادیر درجه حرارت،رطوبت نسبی و دی اکسید کربن موجود در درون غار در دو دوره 30روزه در فصول تابستان و پاییز گردید.در مرحله بعد،با شبیه سازی همین شرایط در محیط آزمایشگاهی کنترل شده،مقدار سالانه انحلال و پوسته پوسته شدن اشکال ثانویه درون غار، به روش وزنی محاسبه گردید. با به دست آوردن تفاضل بین مقادیر دی اکسید کربن مناطق آزمایش و کنترل و تعیین سهم عوامل طبیعی و انسانی،سهم گردشگران در انحلال و پوسته پوسته نمودن اشکال ثانویه درون غار به دست آورده شد.نتایج حاصل از پژوهش نشان می دهد که مقدار انحلال و پوسته پوسته شدن اشکال ثانویه درون غار علیصدر 078/0 گرم بر سانتی متر مکعب در سال است.از این مقدار، 060/0 گرم بر سانتی متر مکعب در سال، معادل 77درصد کل انحلال سالانه سهم گردشگران می باشد.این امر در درازمدت اثرات قابل توجهی در تخریب اشکال کارست ثانویه درون غار ودر نهایتکاهش پایداری صنعت گردشگری منطقه دارد.
    کلیدواژگان: گردشگران، انحلال کارست، اشکال ثانویه، غار علیصدر، همدان
  • احمد پوراحمد، سعید زنگنه شهرکی، محمود آروین صفحه 17
    رشد کالبدی - فضایی شهرها سبب مشکلات فراوانی از جمله اتلاف انرژی، تخریب محیط زیست، افزایش هزینه زیرساخت ها و خدمات، تغییر کاربری زمین های مرغوب کشاورزی، آلودگی هوا و آلودگی خاک، عدم تامین نیازهای ساکنان و... شده است. از رویکردهای مطرح شده در انتقاد به این مسائل می توان از رشد هوشمند، مدیریت رشد، نوشهرگرایی، شهر فشرده و توسعه میان افزای شهر نام برد. توسعه میان افزا به دنبال بهره برداری از زمین های خالی، بهسازی و نوسازی بافت های فرسوده و توسعه مجدد و استفاده از ظرفیت های استفاده نشده زمین در شهر است. جهت اجرای رویکرد توسعه میان افزا در شهر ابتدا باید به شناسایی ظرفیت ها و اولویت های توسعه در شهرپرداخت. در همین راستا، در این پژوهش، هدف شناسایی اراضی و بافت های مناسب جهت توسعه میان افزا و توسعه مجدد است. تحقیق از نظر هدف کاربردی و روش تحقیق، توصیفی - تحلیلی است. ابتدا معیارهای مناسب موضوع انتخاب گردید و در محیط GIS لایه های مناسب با استفاده از نرمال سازی فازی و توابع مناسب، نرمال سازی شده اند. جهت تخصیص وزن به لایه ها، از دو مدل دیمتل و ANPاستفاده شد بدین ترتیب که روابط معیارها با استفاده از مدل دیمتل در محیط نرم افزار Excel و Matlab مشخص گردید سپس با تعیین روابط، وزن شاخص ها با روش ANP محاسبه گردید و در لایه های مورد نظر ضرب شده و از مدل ویکور جهت تلفیق نقشه ها در محیط GIS استفاده شد و نقشه نهایی اولویت بندی بافت کالبدی جهت توسعه میان افزا در پنج طبقه ارائه شده است و همچنین کاربری ها را بر اساس اولویت (با توجه به ارزش پیکسل) جهت توسعه میان افزا طبقه بندی کرده و اولویت اول با مساحت 04/26646871 مترمربع شامل کاربری هایمخروبه، صنعتی، نظامی، ورزشی، تاسیسات شهری و تجهیزات شهری می شود که در کل شهر پراکنده شده اند؛ همچنین سایر اولویت ها همانند اولویت اول در کل شهر پراکنده شده اند و فقط اولویت چهارم بیشتر در محدوده مرکزی شهر قرار دارد.
    کلیدواژگان: رشد کالبدی، فضایی، توسعه میان افزا، توسعه مجدد، شهر اهواز، تکنیک های تصمیم گیری ترکیبی
  • جهانگیر خزائی، مهدی قائمی صفحه 39
    گزارشات متعدد وقوع زمین لغزش در کیلومتر 194 پروژه راه آهن غرب در استان کرمانشاه، منجر به انجام تحقیق پیش روی در مورد علل و نحوه گسترش لغزش زمین در منطقه مذکور و مطالعه روش های پایدارسازی زمین لغزش گردید. در این پژوهش، به بررسی نقش جاده سازی در وقوع زمین لغزش و بررسی روش های موثر در پایدارسازی زمین لغزش و مقایسه عملکرد و کارایی روش های مذکور پرداخته شده است. در این تحقیق، با عملیات نقشه برداری، جابه جایی و حرکت نقاط معینی در محدوده زمین لغزش در فواصل زمانی مشخص نسبت به نقطه مبنا در خارج از محدوده لغزش طی 4 ماه متوالی قرائت و کنترل گردید. آزمایش های شناسایی در محل، توسط کارشناسان پژوهشگاه بین المللی زلزله و آزمایشگاه فنی مکانیک خاک استان انجام گردید. مدل سازی سه بعدی زمین لغزش در نرم افزار FLAC-3D بر اساس نتایج نقشه برداری و حفر گمانه ها، انجام شد. برای پایدارسازی زمین لغزش از روش اصلاح هندسی شیب و نصب زه کش استفاده شده و شیروانی پس از اصلاح شیب مجددا در نرم افزار، مدل و تحلیل گردید. نتایج مدل سازی شیب اصلاح شده نشان از کاهش میزان جابه جایی و پایداری شیب دارد. در ادامه، روش پیشنهاد شده توسط مهندس مشاور طرح نیز در نرم افزار مدل سازی و نتایج با روش اصلاح هندسی مقایسه شد. نتایج به دست آمده نشان می دهد که روش اصلاح هندسی نسبت به روش های دیگر در پایدارسازی زمین لغزش عملکرد بهتری دارد.
    کلیدواژگان: زمین لغزش، راه آهن ملایر، کرمانشاه، ضریب اطمینان، پایدارسازی شیب، اصلاح هندسی
  • اسماعیل علی اکبری، مصطفی طالشی، محمد فرجی دارابخانی صفحه 55
    نظام شهری ایران به دلیل تمرکز امکانات و خدمات در شهرهای بزرگ، از الگوی کهکشانی در قبل از سال 1300، به الگوی زنجیره ای متمایل شده است. این الگو، ضمن بر هم زدن روابط منطقی شهرهای کوچک، میانی و بزرگ با یکدیگر، باعث آشفتگی و عدم تعادل فضایی در نظام شهری - منطقه ای آن شده است که در غرب کلان منطقه زاگرس نیز به مقدار بیشتری وجود دارد. هدف این پژوهش، تحلیل و کاهش عدم تعادل های شهری - منطقه ای و فضایی منطقه مطالعاتی با روش توصیفی - تحلیلی است، از روش های کتابخانه ای بر مبنای سرشماری ها و در تحلیل فضایی از مدل رتبه - اندازه و شاخص های چهارشهر و نخست شهری و فن GIS و نرم افزارExcel نیز استفاده شده است. نتایج نشان می دهد علی رغم استقرار متوازن شهرها در سطح منطقه، توزیع و بارگذاری جمعیت در بین رده های جمعیتی و طبقات شهری آن با ناموزونی و عدم تعادل های شدید در نظام شهری مواجه است. به طوری که روستا - شهرها و شهرهای کوچک با 90 درصد شهرها، 32 درصد جمعیت را داشته اند که فقط به اندازه جمعیت نخست شهر کرمانشاه است. رتبه - اندازه موجود شهرها به ویژه در قاعده هرم شهری به شدت با رتبه - اندازه مطلوب آنها اختلاف دارد و سنجش بلندمدت درجه نخست شهری بر اساس شاخص های یاد شدهروند صعودی به سمت عدم تعادل و ناموزونی بیشتر را نشان می دهد. علی رغم تاکید سیاست های توسعه شهری - منطقه ای بر رویکرد شهرهای کوچک در رفع نابرابری ها، اما روندهای شهرنشینی منطقه، برخلاف سیاست های فوق، تمرکزگرایی و قطبش بیشتر را موجب شده و شهرهای کوچک با وجود سهم 40 درصدی، نه تنها نتوانسته اند یکپارچگی و تعادل فضایی را پس از 35 سال بهبود بخشند، خود نیز با ناپایداری و ناکارآمدی مواجه اند. این مسائل با نبود پیوندهای لازم بین طبقات شهری منطقه، موجب ناهمگونی، ناکارآمدی و تکامل نیافتگی نظام شهری آن شده است.
    کلیدواژگان: توسعه نامتوازن، نظام شهری، نخست شهری، تعادل فضایی، ناپایداری، شهرهای کوچک
  • محمدحسین رضائی مقدم، محمدرضا نیکجو، حسام ملکی صفحه 73
    استفاده از مطالعات ژئومورفولوژی، باتوجه به پیشرفت های اخیر در هیدرولوژی دیرینه سیلاب، به عنوان مکملی برای نگرش های هیدرولوژی متداول مورد نیاز است. رودخانه سیروان به عنوان یکی از شاخص ترین رودخانه های واقع در غرب کشور، سیلاب های زیادی در طول سال داردو با توجه به شواهد ژئومورفولوژیک موجود در مسیر جریان رودخانه، سیلاب های بزرگ تری نیز در گذشته داشته است. هدف این پژوهش، برآورد حداکثر دبی در دوره های مختلف 2 تا 1000 ساله، بر اساس شواهد ژئومورفولوژیک موجود در مسیر رودخانه هست. با شناسایی شواهد سیلاب های دیرینه در 17 مقطع از دره رودخانه، به صورت سایت های مجزا نقشه برداری شد و نقشه با مقیاس 1:1000 تهیه گردید تا بر اساس آن بالاترین سطح تراز آب تعین شود. از نرم افزار LAND، HEC-RAS و GIS جهت بازسازی چینه ها، ترسیم نقشه هاوتحلیل های هیدرولیکی بهره گرفته شد. نتایج نشان داد که حداکثر دبی سیلابی برای دوره 2 ساله،66/103 و برای دوره 1000 ساله 78/4785 مترمکعب بر ثانیه و تراز آب در دوره 2 ساله، 42/868 متر و برای دوره 1000 ساله 91/885 مترو تراز آب در حالت بحرانی برای دوره بازگشت 2 ساله،28/866 متر و برای دوره 1000 ساله 35/874 به دست آمد. حداکثر دبی لحظه ای رودخانه در سال های 1347 و 1352 با دبی 89/137 مترمکعب در ثانیه نشان داد که وقوع سیلاب های بزرگ دور از انتظار نیست. با استفاده از شاخص دیرینه تراز PSI، می توان سیلاب های بزرگ (حداکثر دبی) را در کانال رودخانه از طریق نرم افزار HEC-RASو HEC-GEORAS برآورد و تشریح نمود. بهره گیری از شواهد ژئومورفولوژیک سیل، داده های بیشتری را برای داده های سیستماتیک در حوضهرودخانه های بدون ایستگاه های هیدرومتری فراهم کرده است و در نتیجه منجر به برنامه ریزی دقیق تر در طراحی سازه ها و پهنه های خطر سیلاب در حاشیه رودخانه می شود.
    کلیدواژگان: شواهد ژئومورفیک، رودخانه سیروان، مدل HEC، RAS، برآورد دبی، رسوبات آب راکد
  • جعفر توکلی، داود جمینی صفحه 89
    با توجه به مصرف بیش از 90 درصد منابع آبی کشور در بخش کشاورزی، مدیریت منابع آب در این بخش، از جایگاه و اهمیت ویژه ای برخوردار است و برنامه ریزان و سیاست گذاران کشور را بر آن داشته تا با به کارگیری ابزار و فن آوری های مختلف، میزان آب مصرفی در این بخش را با حفظ میزان تولیدات، به حداقل برساند. تجهیز اراضی زراعی به سیستم های آبیاری بارانی از جمله اقدامات مهم برنامه ریزان کشور در راستای مدیریت منابع آب است که در سال های گذشته تا کنون، در مناطق مختلف کشور از جمله شهرستان روانسر مورد استفاده کشاورزان قرار گرفته است. هدف از پژوهش حاضر بررسی و تحلیل اثرات سیستم های آبیاری بارانی بر فعالیت های کشاورزان و همچنین، شناسایی عوامل پیش برنده تجهیز اراضی زراعی به سیستم های مذکور در مدیریت منابع آب روستاهای شهرستان روانسر است. جامعه آماری پژوهش را کلیه کشاورزان استفاده کننده از سیستم های آبیاری بارانی طی سال های گذشته در شهرستان روانسر تشکیل می دهد (190 نفر) که از میان آنها، 181 نفر در دسترس بوده و حاضر به مصاحبه با محققان شده و نظراتشان مورد تجزیه و تحلیل قرار گرفته است. ابزار اصلی پژوهش پرسشنامه محقق ساخته بوده که روایی و پایایی آن به ترتیب توسط اساتید و کارشناسان مربوطه و محاسبه ضریب آلفای کرونباخ مورد تایید قرار گرفت. نتایج پژوهش با استفاده از آزمون ویل کاکسون نشان داد اثر سیستم های آبیاری بارانی بر فعالیت کشاورزان در کلیه شاخص های مورد بررسی، مثبت و معنی دار بوده است. نتایج آزمون t تک نمونه ای نشان داد میزان رضایت مندی کشاورزان از سیستم های مذکور با میانگین 762/3، بالاتر از حد متوسط بوده است. نتایج تحلیل عاملی اکتشافی در شناسایی پیش برنده های تجهیز اراضی زراعی به سیستم های آبیاری بارانی در محدوده مورد مطالعه نشان داد پنج عامل شناسایی شده توانسته اند حدود 73 درصد واریانس متغیر وابسته پژوهش را تبیین کنند. عوامل شناسایی شده و مقدار واریانس آنها به ترتیب اهمیت عبارت اند از: سیاست های حمایتی (168/19)، تقویت نظام آموزشی - ترویجی (308/17)، مشارکت فعال کشاورزان (459/13)، قابلیت و کارآیی اراضی زراعی (181/12) و عوامل زمینه ای (893/10).
    کلیدواژگان: پایداری منابع آب، کشاورزی، سیستم های آبیاری بارانی، شهرستان روانسر
  • مسلم عارفی، محمد میره ای، کرامت الله زیاری صفحه 101
    نابرابری های بین منطقه ای و درون منطقه ای، به عنوان مشکلی بزرگ در توسعه منطقه ای کشورهای در حال توسعه وجود دارد. این نابرابری ها از نتایج سیاست های رشد قطبی به شمار می آید و این نابرابری ها مخالف اصول توسعه پایدار و متوازن و عدالت محور است. دغدغه اصلی این کشورها، همواره رسیدن به یک توسعه متعادل بوده است. برخلاف سیاست های توسعه منطقه ای در ایران که بر اساس کاهش شکاف میان توسعه مناطق مختلف و ایجاد تعادل در توسعه منطقه ای است، هنوز هم برخی مناطق و نواحی از کمبود خدمات و تسهیلات پایه ای رنج می برند. هدف این پژوهش سنجش وضعیت توسعه یافتگی و تعیین میزان نابرابری های آن در بین نواحی (شهرستان های) استان لرستان است. در این پژوهش، برای گردآوری اطلاعات، از روش کتابخانه ای استفاده شده است. در راستای انجام پژوهش، از 40 شاخص در قالب 6 متغیر (خدمات عمومی شهری و زیربنایی، اجتماعی - جمعیتی، اقتصادی - صنعتی، آموزشی، بهداشتی - درمانی و کشاورزی) بهره گرفته شده است. این پژوهش درصدد بررسی نابرابری های توسعه ای در طول دوره مورد نظر است و از تکنیک های ویکور و ضریب تمرکز و ضریب توزیع برای بررسی نابرابری در استان استفاده شده است. نتایج به دست آمده نشان دهنده عدم توزیع هماهنگ امکانات و خدمات در سطح نواحی استان می باشد. تصمیمات سیاسی، امکانات محیطی، محورهای توسعه، محدوده های صنعتی و شبکه های زیر بنایی عمده، نقش موثری در سطوح برخورداری شهرستان های استان دارند. همچنین روند نابرابری ها در طول دوره افزایش داشته است و سیاست های تمرکز زدایی در استان نتوانسته است موفق عمل کند. در ادامه نیز با تاکید بر تقویت بخش های حاشیه ای و توسعه نیافته استان، پیشنهادهایی جهت کاهش عدم تعادل توسعه در استان لرستان ارائه شده است.
    کلیدواژگان: توسعه نامتوازن، نابرابری، مدل ویکور، ضرایب توزیع و تمرکز، استان لرستان
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  • Amjad Maleki, Mohammad Hosayn Ghobadi, Payman Karimi Soltani Page 1
    Introduction
    As the most tourist attracting water cave in the country, Ali Sadr cave, located in Hamadan-Kabdtar Ahang, attracts thousands of internal and external tourists each year. It is considered as one of the most well-known caves in the world not only for its beauty but also for the numerous tourists it attracts. As a matter of fact more than 12000 people visit the cave during warm seasons, especially on holidays and weekends. Due to a lot of breathings, simultaneous entrance of tons of visitors into the cave makes the carbon dioxide concentration increase. Mixing with relatively high humidity which is saturated or near to be saturated, they make an acid environment inside the cave, especially in the roof including a lot of gaps and tracks. This phenomenon leads to corrosion and shelling out the secondary shapes available inside the cave namely stalactites, stalagmites and curtains. The present study aims at finding the role of visitors in corrosion and shelling out the secondary shapes in Ali Sadr Cave based on the Weight method. Therefore, the related data such as temperature, relative humidity and the cave carbon dioxide are gathered in order to simulate the cave climate in controlled laboratory conditions.
    Materials And Methods
    In order to gather the related data to the role of visitors in climate elements variation and available Carbone dioxide inside the cave, the cave space is divided into two experimental region (visitors moving location) and controlled region (forbidden and uncleansed regions). Moreover, the tunnels, channels and lobbies are divided into three regions called low, middle, and high statures to increase the accuracy of data gathering and also considering different carbon dioxide concentrations in the channels and lobbies with different dimensions. The data were gathered by applying Co2 detector system type AZ77535 during a 30-day period in summer (at the time of maximum visitors’ entrance to the cave) and another 30-day period in fall (at the time of minimum visitors’ entrance to the cave). As the average data for Carbone dioxide, relative humidity, temperature and visitors portion in the data concentration increase and decrease were determined, the inside climate of the cave was simulated in the controlled laboratory condition. After precise determining of physical and chemical features, the disk stone samples, taken from three regions inside the cave, were tested in three glass chambers with different cycles during 60 days based on the numerical minimum, average and maximum of obtained carbon dioxide. The numbers were the result of a 60-day data gathering and the simulation of temperature and relative humidity in the experimental region inside the cave. After removing the samples from the glass chambers and determining exact physical properties, the solving and corrosion rates were obtained separately for natural and human influential factors based on weight method.
    Result and
    Discussion
    The findings reveal that the amount of the dissolution and lamination of the secondary shapes inside the Ali Sadr Cave is 0.078 G/cm3 annually that 0.060 G/cm3 of this amount equals to 77% of the total annual dissolution of the tourists portion. The results of the variance analysis of the taken carbon dioxide from the inside of the cave show that the concentration of carbon dioxide in the experimental areas in the summer simultaneously with the presence of the maximum number of visitors in different hours has significant differences. However, these dioxide concentration differences are not significant in the salons and corridors with different height. In other words, the size and height of the corridors are not regarded so important in the caves visited by a large number of tourists, for the concentration of carbon dioxide is the same through the cave. As a matter of fact, the dissolution and destruction of the cave walls and shapes happen in the same rate and amount.
    Conclusion
    One of the most important phenomena which attracts thousands of tourists into the caves annually is the secondary interesting and fascinating shapes. The more gradual destruction of these wonderful shapes, the more decrease in the number of the tourists. In fact, the investment and advertisement which aims at increasing the number of the tourists not only can have a negative effect on the long run, but also can decrease the number of the visitors as a result of secondary shapes destruction in the cave. In the long run, this process will have significant effects on destroying the secondary Karst shapes inside the cave leading to decrease the stability of the tourism industry in this area.
    Keywords: Tourists, Karst Dissolution, Secondary Shapes, Alisadr Cave, Hamedan
  • Ahmad Pourahmad, Saeid Zanganeh Shahraki, Mahmoud Arvin Page 17
    Introduction
    Spatial - physical growth of cities makes many problems such as waste of energy, destruction of environment, an increase of urban infrastructure and service expenses, a change of agriculture land application , air and soil pollution, lack of security for the residents’ demands etc. Some proposed approaches to criticizing these problems are smart growth, growth mangement, new urbanism, campact city and urban infill development. Infill development is trying to utilize vacant lands, rehabilitation and renovation of old textures, redevelopment and applying the unused capacity of lands in the city. The emergence of some problems due to physical-spatial growth of Ahvaz shifts the attention to critical approaches against horizontal distribution. Some of these problems are the low level of quality of life and human development indicators, lack of full enjoyment of Ahvaz residents from residential units, vast old texture in the middle of the city with urgent need for redevelopment and reorganization, concentration of about 40 percent of the city population in unsustainable areas of the city etc. The present study aims at identifying the redevelopment capacities of physical texture of Ahvaz regarding both the effective factors on urban development and prioritizing the identified textures for redevelopment.
    Materials and
    Methodology
    The Research aims at identifying the lands and redevelopment capacities by applying the hybrid decision making models in GIS. As the first step, the exact definition of the problem is provided. Then, according to research goals, at first, the factors and criteria were collected through literature review and interviews with the experts. Since the relationship between the criteria and their effects was different from the goal of the study, two questionnaires called Dematel and ANP were applied. As the first step, Dematel questionnaire was given to the experts and elites. When the relationships among the criteria were determined and drawn based on the Dematel output, the second questionnaire was given to decision makers to calculate the weight and their importance. Generally, when the problem is identified in the spatial multi-criteria analysis, it is necessary to show each criterion in the form of a layer in GIS-based databases. Therefore, the criterion maps were prepared in the environment of ARC GIS software. Moreover, the fuzzy function was applied to standardize the layers in the environment of ARC GIS. The fuzzy function, incremental linear function and other layers are standardized in a way that two different functions are standardized by positive and negative layers. In the final step, using GIS capabilities, MCDM method and VIKOR technique were used to combine the layers and identify lands and redevelopment potential respectively.
    Results And Discussion
    The final prioritize map of physical texture is presented in five classes to reach infill development. The first priority with the area 26,646,871.04 m2 includes desolated, industrial, military and sports applications, urban facilities and urban equipment which are dispersed throughout the city. Moreover, except for the fourth priority which is located in the central part of the city, other priorities are dispersed throughout the city; like the first priority.
    This research considers the infill development of Ahvaz, for this city is dealing with many problems due to the sprawl problem. From the infill development strategies, the strategy of physical texture redevelopment is chosen as the main research strategy. Infill development has been studied in previous research in different aspect like the physical criteria (materials, building life, building quality etc.), environmental (slope, soil type and erosion), accessibility (access to service, and various necessary infrastructure including water network, sewerage, electricity, gas, etc.) buffer and limitations (river, industrial usage, etc.). In this research, in addition to the aforesaid criteria, education and employment in infill development debate are used. The employment criterion shows the ability of the owner resident to participate in development, while education criterion indicates the people's participation due to their awareness. Redevelopment and infill development consist of different strategies such as incompatible transmission of land application, using the vacant lands, rehabilitation and renovation of old textures and slums, etc. The target redevelopments of this research are the textures and lots having access to service applications, observing the restrictions and buffers, and having high potential level in terms of participation.
    Conclusion
    The cities of Iran are facing the problems like boundless spread of city, the destruction of agricultural lands and environmental problems due to lack of careful planning about land application which lead to not only inefficient application of the capabilities and available potentials but also improper observation of the population pattern settlement. Weakened physical conditions of the neighborhoods and the dissatisfactions can eventually lead to the loss of neighborhoods, cities and finally whole metropolitan area. In this condition, the urban infill development makes the lands and old buildings ready for re-application, help to the development of the city perspective and life environment, increase the opportunity of buying house, and help to attract and retain the residents with various incomes. Therefore the quality of life in old neighborhoods is enhanced. The present study aims at identifying the infill redevelopment potential of physical texture in Ahvaz. At the end of research, the final map made in the classified physical texture and infill development priorities are presented. Besides, the applications are prioritized based on the priority (according to the pixel value) to infill development. First priority includes desolate, industrial, military, sports and urban infrastructure, and urban equipment.
    Keywords: Spatial, physical growth, Infill development, Redevelopment, Ahvaz, Decision, making techniques
  • Jahangir Khazaei, Mehdi Ghaemi Page 39
    Introduction
    Landslide is considered as one of the reasons of natural resources loss in mountainous areas, leading to sever property damages and casualties worldwide (Fele Gray et al., 2013: 228). According to the United Nations’ report, landslide damages in developed countries is as equal as 1 to 2 percent of their gross domestic product, GDP (Lerouil, 2006: 198). The most well-known natural factors affecting the landslide are rainfall, lithology, slope etc. (Talebi and Niazi, 2011: 66). Moreover, road-building is considered as an effective human factor in the occurrence of landslides (Kelarestaghi, 2002: 5). In a research on the spatial association between the occurrence of landslides and roads in the forest regions, Larsen and Parks (1997) revealed that road building will increase the effect of the landslide by 5 to 8 percent.
    In spite of providing several methods regarding the stabilization of landslide by different researchers, there is no unified consensus. Ramezani and Ibrahimi (2009) stated that, unlike the landslides made by non-natural factors, it is not often easy to control the ones made by natural factors.
    In the present study, considering the uncertainties about a convenient and practical method to stabilize the landslide occurred on the kilometer 194 of the railway Malayer – Kermanshah (located between Aran, Kangavar and Ahangaran-e Sahne village), first, the stability of the aforesaid landslide will be discussed. Then, the geometry of landslide in different states including the present slope (unstable), the slope with modified geometry (the proposed method in this study), the modified slope proposed by consultant engineer, and the stabilized slope by pile system is modeled in FLAC 3D software, considering soil characteristics determined by the soil mechanics laboratory. Besides, the results will be evaluated and compared in order to choose the most appropriate method for landslide stabilization.
    Materials and
    Methodology
    In this study, stability of a particular slope having different boundary condition has been modeled and analyzed using version 3 of FLAC 3D. In fact, geometry of slope was modeled in different conditions including unstable slop, slope with modified geometry (method proposed in this study), modified slope using proposed method by consulting engineers (Hexa Consulting Engineers, 2011), and stabilized slope using the pile systems (case studied in Malayer - Kermanshah railway). The soil characteristics were determined by soil mechanics laboratory. Moreover, the Mohr-Columb model, as the most practical model in soil slope modeling, was used. For the sake of validation, slope modeling was analyzed in Geoslope software version 2007 (limit equilibrium methods) in both natural and stabilized modes. Furthermore, the behavior of the progressive landslide was monitored using five stable monitoring points in different locations. The monitoring points were installed from bottom to the top of the slope which were mapped during four consecutive months, from September to December 2012, with ten-day intervals. Numerical findings were confirmed by comparing not only the consecutive mappings but also the latest and first mappings.
    Results And Discussion
    Slope analysis of the status quo proved the maximum displacement of 185 cm and a safety coefficient of slope stability of 1.26. High values of displacement marks the instability of the slope in this particular case. Slope modeling, after geometric correction, revealed a decrease in the displacement up to 71 cm, and an increase in the safety coefficient to 1.61. The proposal of the project consulting engineer suggested the slop adjusting and a concrete gallery implement to cross the railway track. In this case, the displacement in the gallery wall in the middle of the wall and the corners is 40-50 cm and 30-40 cm respectively, which may cause severe damages to the side of the gallery in case of landslide activity. Besides, the maximum displacement of the slope in this case is a bit more than 95 cm. In terms of stability safety, it should be noted that the maximum displacement in this case is less than 100 cm, so the amount of displacement is legal but on the edge of insecure borders. This condition can be soften by applying the procedures such as drainage. In the case of the pile application for stabilization, the largest landslide displacement was about 30cm, which was quite in a normal range, although it needs considerable operating expenses.
    Conclusion
    The findings of this study revealed that gallery implement method proposed by the project consulting engineer and stabilization method with piles are the most appropriate method for stabilizing the slope. The aforesaid method not only is economical, but also preserved the environment with the least interface in nature. Moreover, its safety and output are confirmed by the analytical model in FLAC 3D software. In the proposed method, geometric correction with drainage is cheaper, the displacement is lower, and the possibility of damage to the embankment is less. Moreover, in case of damage, it is easier to repair. Combining this method with Bio-engineeringmethods, such as planting of vetiver grass can increase the slope stability.
    Keywords: Landslide, Malayer, Kermanshah railway, safety coefficient, slope stabilization, Geometric correction
  • Esmaeel Aliakbari, Mostafa Taleshi, Mohammad Faraji Darabkhani Page 55
    Introduction
    The formation and development of small towns and big cities in the urban system of industrial countries are mainly in accordance with the steps of growth and industrial development having a balanced pattern. Unlike developed countries, the rapid growth of urbanization and lack of coordination with stages of industrial development have created new problems in urban systems of developing countries changing the focus of the huge number of urban population in one or two major cities of these countries. The main issue in the process of socio-economic development of Iran is the rapid urbanization as a result of the influx of migrants from the villages, the small and intermediate towns to the big cities leading to imbalance distribution of population and activities. As a matter of fact, there are three major challenges in the spatial distribution of urban population in Iran: The concentration of population in big cities, urban network changes and hierarchal urban pattern, as the urban galactic and homogeneity network of Iran have been discrete, changing to the chain network. It leads to some natural reflections namely urban dominance, the concentration of population and activity in big cities, balance disturbance of urban network and System and the emergence of The Prime Urban Pattern which is mainly based on the concentration of economic, social and demographic activities. Appearing in the west of Zagros macro-region, this model makes not only a turmoil in logical relations among small, middle and large cities, but also a disturbance and lack of spatial balance in urban-regional system.
    Materials and Methodologies: Applying descriptive-analytical method, the present study aims at analyzing and reducing the urban-regional imbalances in the studied region based on small town development. The data were gathered based on the Population and Housing censuses Statistics, during a period from 1976- 2011 by applying the library method. Rank-size model, primacy and four-city indicators, GIS and Excel software were used to spatial analysis of the region.
    Results And Discussion
    The findings reveal that despite a balanced establishment of cities across the region, the population distribution and loading among the urban population and classes are facing a severe imbalances in the urban systems. In other words, according to the last census, although the rural-towns and towns make over 90 percent of the cities in the region, they include only 32 percent of the population which equals to the population of prime city of Kermanshah. The present rank-size city, especially in the base of the urban pyramid, is largely far from the ideal rank-size. Furthermore, periodic evaluation and long-term concentration, based on the primacy and four-town indicators, show the uptrend tend to more imbalances. Despite the emphasis of urban-regional development policies on the approach of small town in removing regional disparities, the process of urbanization in the region, in contrast with the aforesaid policies, makes more centralization and polarization. Besides, despite the 40-perscent contribution of small cities, they not only cannot improve the sustainability, the integrity and spatial balance after 35 years, but also face instability and inefficiency in the region. Spatial manifestation of these instabilities and inefficiencies can be recognized in the following cases: unsuccessful approaches to attract the population overflows of big cities on the one hand, and their rural regions on the other hand, unsuccessful approaches in redistribution and balanced spread of urban population through the region, unsuccessful approaches to reduce the prime urban problem, facing more than 14 percent decrease of the population and more than 33 percent decrease in the number of the shares of these cities in 2011 compared with 35 years ago in 1976, sensible long-term stagnation and static of these cities in the small town class making not only the region face the severe vacuuming in the intermediate cities, but also a few of small towns improve to intermediate class cities as the balancer cities, confronting of a number of small towns with the negative growth and depopulation and degradation to rural towns of region. As map 1 shows, these inefficiencies and instabilities have caused a severe inharmonious and polarized illustration of uploading and the distribution of urban population in the west of Zagros macro-region which represents a complete polarized place with high concentration and density of urban population in large cities of Kermanshah and Sanandaj in center of the region in the first level, the triangle of intermediate cites Saghez, Baneh and Marivan in the northwest and intermediate cities Islamabad and Ilam in the south of the region in the second level. These issues along with the lack of coordination and lack of the necessary linkage among various cities of urban systems lead to not only the heterogeneity and inefficiency of urban systems but also incomplete development of the system.
    Conclusion
    The west of Zagros macro-region is facing inequality and lack of unique spatial integrity. Although a considerable number of small towns are made as result of some approaches of regional development based on small towns to establish an integrated and balanced development, these cities could not fulfil their developmental and decentralizing roles due to both poor service, production and facility infrastructures and lack of investments; facing a lot of inefficiencies.
    Keywords: Imbalanced development, Urban system, Prime city, Spatial balance, Transience, Small towns
  • Mohammad Hosayn Rezaei Moghaddam*, Mohammadreza Nikjoo, Hesam Maleki Page 73
    Introduction
    Determining the characteristics of floods are considered important to plan and control them. According to geomorphological evidences of the river flow, Sirvan River, as one of the most significant rivers in the west of the country, has had some floods in the past. The present study aims at simulating and analyzing Sirvan River floods based on geomorphological evidence. As a matter of fact, long estimation would lead to predict the river behavior and flood appropriately, therefore it is necessary to search for possible estimations to do river planning vigilantly.
    Materials and
    Methodology
    Topographic maps scale of 1: 1000, Total Station mapping camera, the application of GIS, HEC-RAS and research are the most important and practical materials and tools applied in the present study. The flood evidence was identified as a result of mapping and field surveys. Moreover, the metric measurements of the stratigraphy were drawn in the environment of drawing LAND software.
    Determining the Manning roughness coefficient, the data were entered the environment of additional GEO-RAS from GIS environment to model the riverbed. The output was sent to the environment of HEC-RAS to present hydraulic simulation. Finally, the output was presented as transected and longitudinal sections.
    Results
    The findings of positioning flood level with different return periods showed that the flood discharge increased for each longer return periods and there was an addition on the flood level in each sections. The profile of each section shows the increase and decrease of the flood regarding the other sections. In fact, as the section level increases, high-profile flooding decreases. The maximum instantaneous discharge of Sirvan River during a 48-year period reveals that the occurrence of large discharges is expected, therefore, Sirvan River can be counted as the flooding rivers.
    Discussion
    The simulation of Sirvan River Valley floods was done applying hydraulic model HEC-RAS. Besides, the morphological flood evidence (stagnant water deposits) in paleo flood reconstruction was used to estimate the maximum flow discharge rate. As a matter of fact, statistical and experimental methods to estimate this river discharge and the adoption of wrong results by the civil engineers have had irreparable property and fatality damages. The investigations showed that using ancient Paleo indicator of PSI can help to estimate and analyze the maximum discharge in the river channel in the environment of HEC – RAS software.
    Conclusion
    It is not safe enough to rely on short-term statistics of hydrometric stations and experimental methods to estimate the floods’ discharge. Estimated discharge in different return periods shows that the occurrence of severe floods is expected. Applying geomorphological evidences of the flood provide more data for the systematic data and the basin of the rivers with no hydrometric stations. As a result, long estimation would lead to predict the river behavior and flood, therefore it is necessary to search for possible estimations to do river planning vigilantly.
    Keywords: Geomorphic evidence, Sirvan River, HEC, RAS model, Discharge estimation, Slack of sediment water
  • Jafar Tavakoli, Davoud Jamini Page 89
    Introduction
    According to FAO report to achieve the Millennium Development Goals, the first goal is to eradicate extreme poverty and hunger worldwide in 2015. The investigations indicate that except for hundreds of million people worldwide who do not have the acceptable level of food security, there will have been the serious risk of feeding for more than 9 billion people by 2050. General Director Deputy of FAO claimed that agricultural productions should be increased by 70 percent around the world while by 100 percent in developing countries to reply increasing food demands. Despite the importance of agricultural productions in providing food security and dependence of agricultural production to water resources, the evidence proves that Iran is in inappropriate condition in terms of water resources. Due to more than 90 percent consummation of water resources in agricultural part, water resource planning is of great importance. In fact, applying various tools and technologies, this importance makes the planners and policy makers decrease the amount of consuming water while keeping the rate of productions at the same time.
    Equip agricultural land sprinkler irrigation system is of a kind of the important actions applied by the country planners which aims at managing the water resources around the country. The system is being used by the farmers through different parts of the country, namely Ravansar, in recent years. The present study aims at not only analyzing the effects of sprinkler irrigation systems on agricultural activities but also recognizing the driving factors of farm land equipment to sprinkler irrigation systems in managing the water resources of Ravansar rural regions.
    Materials and
    Methodology
    The present quantitative study is of a kind of applied researches in essence and the descriptive-analytic one regarding methodology in which the data are gathered by using documentary and field methods. The statistical population consists of all farmers using sprinkler irrigation systems in Ravansar in recent years (190 people). 181 of them were available willing to interview with the researchers; their comments were analyzed. The main research tool is a researcher-made questionnaire, whose validity, reliability and Cronbach's alpha coefficient were confirmed by university professors and relevant experts Wilcoxon test has been used to determine the effects of sprinkler irrigation systems on the farmers’ activities. Moreover, one-sample t-test and exploratory factor analysis were applied to test the farmers’ satisfaction of sprinkler irrigation systems and recognition the driving factors of sprinkler irrigation systems adoption respectively.
    Results And Discussion
    The use of sprinkler systems among the farmers of Ravansar has had considerable influences on the farmers’ activities regarding cost-saving indices namely irrigation, saving labor power, development of water lands, increase of crop yields, saving water, reduction of soil degradation and erosion, the tendency to be more active in the agricultural sector, increase of crops diversity and decrease of water scarcity problems. Furthermore, the rate of the farmers’ satisfaction proves the satisfaction rate of the farmers form the sprinkler irrigation systems. Besides, the recognition of driving factors equipping agricultural lands to the sprinkler systems in the area indicates that, supportive policies, strong educational-promotive system, active participation of farmers, functionality and efficiency of agricultural lands and background factors are considered as the most important factors. As long as they are strengthened, they provide more background to use more sprinkler systems among the farmers Ravansar.
    Conclusion
    Applying Wilcoxon method, the findings of the research showed that the effect of sprinkler systems on the activities of farmers is positive and significant in all indices. The findings based on one-sample t-test revealed that the rate of the farmers’ satisfaction of the system was about 3.762 which is higher than the average. The findings of exploratory factor analysis showed that the 5 recognized factors can explain about 73 percent of the research dependent variance. Prioritized in order of importance, the recognized factors and their variances are: supportive policies (19.168), strong educational-promotive system (17.308), active participation of farmers (13.459), reliability and efficiency of agricultural land (12.181) and contextual factors (10.893).
    Keywords: Sustainable water resources, Agriculture, Sprinkler systems, Ravansar
  • Moslem Arefi, Mohammad Mireei, Keramat Zayari Page 101
    Introduction
    Comprehensive excellence and growth of human beings are the general goal of development in each society. As a matter of fact, regional inequality and different rate of development are due to the inability in optimal use of a region natural potentials compared with other regions. One of the most important kind of inequality is spatial inequality. In Iran, like other developing countries, one of the significant features in the national spatial development is the presence of regional and spatial disparities which makes the necessity of research inevitable. Nowadays, recognizing the strengths and weaknesses of each region is considered as a kind of necessity for planning. Using different indices can be appropriate enough not only to determine the status area but also, as a factor, to solve the problems of development. Accessing to statistical data on different indices in various areas and processing them using statistical models are regarded as the important steps to achieve the desired goals.
    Development and been developed are the concepts that have no precise definition and comprehensive agreement for them. According to Friedman, development is a creative process and an innovation to make fundamental changes in the social system. In contrast, underdevelopment is an economic condition or development in a region or country that does not have the necessary equipment for initial growth and a high proportion of its resources should be allocated to agricultural work. In recent years, the sustainability concepts and sustainable development in social, economic and environmental policies have attracted a lot of attentions. Focus on regional planning is as one of the important administrative policies to reduce inequalities. It is defined as a way to regulate and coordinate various programs like economic and social programs with local requirements and capabilities.
    The studying region is Lorestan located in the west and southwest of the country. Lorestan is consist of 10 cities, 25 towns, 27 districts and 84 villages. Its capital is Khoramabad.
    Materials and
    Methodology
    The research method is of a descriptive – analytic one. The data and statistics about incises are derived from statistics and year-books. In this study, VIKOR ranking and the Shannon entropy method are applied to rating of the region and weighting to variables respectively. The focus of facilities in the regions is calculated by the models of concentration and distribution coefficients. The data are related to years 1996 and 2014. In this study, Excel and Spss are applied for statistical calculations, while GIS software is used to make graphic maps.
    VIKOR is one of the new methods for solving multi-criteria decision-making that aims at choosing the best option based on the most possible answer to the ideal answer.
    Results And Discussion
    In the present study, VIKOR technique has been used to leveling the regions. In the first stage, the matrix of primary data is formed. In the second stage, the matrix data will be normalized. Then, in the third stage, the values of Salutary (S) and Regret (R) are calculated. In the fourth stage, the final VIKOR coefficient (Q), as a base for raking the options, is then calculated. In the final step, the cities are ranked based on the values of Q, R, and S.
    At this stage, the cities are prioritized from the smallest to the biggest based on the values of Q, R, S. In fact, the city with the smallest Q is considered as the best city if and only if the following conditions are provided:
    Condition A: If A1 and A2 have the first and second rank among m options.
    Condition B: Option A1 must be recognized as the top one at least in one of the R or S group. According to the obtained values, the second condition is establishing during the period 1996-2014.
    Azna and Khoramabad has the highest relative growth, while Delfan has the highest decline. However, Borujourd & Selseleh has no significant change in the period. During the period, the inequality in development levels of the city regions is continuing. The province's major axis of development exists in the eastern part, along the north-south transit route (Tehran) and center of Iran (Esfahan). In contrast, the western part of Kermanshah failed be successful enough and developed less, although it was a communication axis.
    The concentration coefficient is 9.64 and 10.94 in 1996 and 2014 respectively. The difference of concentration coefficient for the periods is 1.3 for the province which reveals that the centralization has had a growing process. In 1996, the highest focus of facilities is for Khoramabad and Aligoodarz, while the lowest concentration coefficient belongs to Borujerd and Kouhadasht. In 2014, the highest centralization in facility distribution is in Khoramabad and Aligoodarz, while the lowest is in Kouhadasht and Dowrehcheginy. The findings of all three models indicate that there is inequality in all levels in Lorestan. This inequality is in both having the blessing of development and facility distribution.
    Conclusion
    The findings reveal that the regional inequality is apparent in all levels of the province, as there is no logical relationship among the abilities, environmental conditions and the development level. In the following, according to the findings, some strategies are presented to reduce the inequality. They aim at achieving the regional balance in the province:
    Development of urban and rural public services
    Promotion of human development, social and cultural indices in accordance with the requirements of development
    Development of industrial activities, especially in the less developed cities which have the special industrial capabilities
    Creating the fair opportunities to access education through the urban and rural regions
    Health promotion of cities, covering health facilities and services through the urban and rural regions
    Increasing the rate of production and productivity of crops
    Increasing the public and private investment
    Planning based on the facilities and the limitations of each city
    Keywords: Unbalanced development, Inequality, VIKOR, Distribution, concentration coefficients, Lorestan province