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جغرافیا و مخاطرات محیطی - پیاپی 22 (تابستان 1396)

نشریه جغرافیا و مخاطرات محیطی
پیاپی 22 (تابستان 1396)

  • تاریخ انتشار: 1396/07/28
  • تعداد عناوین: 10
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  • مقالات
  • سیاوش شایان، عبادالله قلیچی، مجتبی یمانی صفحات 1-16
    جاده کرج - چالوس در شمال و شمال غرب استان تهران از واحدهای توپوگرافی و ژئومورفولوژیک متنوعی عبور می کند که آگاهی از ویژگی های هر یک از این واحدها و شناخت عوامل مورفوژنز و مورفودینامیک فعال و ارزیابی مخاطرات محیطی جاده ای در آن ها، هدف اصلی این تحقیق است. به دلیل انرژی زیاد توپوگرافی (اختلاف ارتفاع نسبتا زیاد با شیب تند، جهت دامنه ها به دلیل برف گیر بودن) وجود این اختلاف روند مورفوژنز و مورفودینامیک را تضمین می کند، در نتیجه فرایندهای فرسایشی از پتانسیل های بالایی برخوردارند. براساس مطالعات و پیمایش های میدانی و نتایج به دست آمده از این تحقیق، فعالیت های زیاد نیروهای تکتونیکی (براساس شاخص تکتونیکی و مدل مک فادن و بول 3 ̸∙) در منطقه و چین ها همراه با گسل ها، فرسایش آبراهه ای و رودخانه ای (شستشو)، حرکات دامنه ای نظیر ریزش، جریانات واریزه ای، لغزش، بهمن های برفی و سنگی، کریوکلاستی، مورفوژنز انسانی و هوازدگی مکانیکی و هوازدگی شیمیایی همراه با یخبندان براساس مدل پلتیر، از عمده ترین عوامل ژئومورفولوژیک شناخته شده در طول مسیر جاده مورد مطالعه می باشند. همچنین پهنه های مخاطرات طبیعی منطقه مورد مطالعه با استفاده از لایه های (توپوگرافی، شیب، هوازدگی، آبراهه، گسل، لیتولوژی، حرکات دامنه ای، کاربری اراضی و جاده) و براساس تکنیک منطق فازی در محیط GIS به دست آمده است که براین اساس پهنه های پر خطر منطبق بر دره ها و محور کرج – چالوس است. نتایج تحقیق، ضرورت درک و آگاهی بیشتر و منطقی از فرایندهای ژئومورفولوژیک منطقه را نشان می دهد. بنابراین قبل از هرگونه اقدام و فعالیت های عمرانی در مسیر جاده، برنامه های مربوط به آمایش سرزمین لازم است، بر مبنای شاخص های ژئومورفیک لحاظ شوند.
    کلیدواژگان: ژئومورفولوژی کاربردی، حمل ونقل جاده ای، کریوکلاستی، مورفوژنز انسانی
  • احمد نوحه گر، محمد کاظمی، سید جواد احمدی، حمید غلامی، رسول مهدوی صفحات 17-35
    فرسایش خاک و تولید رسوب یکی از مخرب ترین پدیده هایی است که موجب خسارت های فراوان در مناطق مختلف شده است. از طرفی جهت مبارزه با این پدیده و اجرای پروژه های حفاظت خاک، نیاز به آگاهی از اطلاعات مکانی منابع رسوبات تولیدی در یک منطقه است. روش انگشت نگاری رسوب بر پایه ردیاب های ژئوشیمیایی، آلی، نسبت های ایزوتوپی و نیز استفاده از مدل های ترکیبی مختلف باعث شناخت سهم منابع مختلف رسوب در یک ناحیه می شود. در تحقیق حاضر با استفاده از ترکیب بهینه ردیاب های آلی، ژئوشیمیایی و نسبت های ایزوتوپی اقدام به تفکیک منابع مختلف فرسایش و تولید رسوب و سپس تعیین سهم این منابع با استفاده از مدل های کالینز (Collins)، کالینز اصلاح شده (M Collins)، موتا (Motha)، لاندور (Landwehr) و اسلاتری (Slattery) شد. جهت تعیین بهترین مدل در این باره از شاخص های GOF، RMSE و تطبیق نتایج با اندازه گیری واقعی مقادیر رسوب برپایه مدل BLM و واحدهای شدت فرسایش استفاده شد. عناصر کربن، مس، تیتانیوم و سیلیکون به عنوان ردیاب های تفکیک کننده واحدهای کاربری اراضی شناخته شدند و مدل ترکیبی کالینز اصلاح شده (M Collins) با شاخص های GOF، 9/99% و RMSE، 07/2% به عنوان بهترین مدل انتخاب شد. نتایج اندازه گیری صحرایی میزان رسوب تولیدی از کاربری های مختلف اراضی نشان داد مراتع با پوشش های گیاهی ضعیف و متوسط و با اهمیت نسبی 87/3 در اولویت مدیریت حفاظت خاک قرار دارند. مدل های ترکیبی نشان دادند بیشترین سهم در فرسایش و رسوب حوزه مربوط به مراتع ضعیف و تخریب یافته منطقه با درصد مساحت 75/16 و سهم 04/57 درصد می باشد و اراضی زراعی کمترین نقش را تولید رسوب منطقه دارند. همچنین نتایج مدل موتا با ضریب همبستگی 924/0 کمترین اختلاف را با مقادیر اندازه گیری شده داشت.
    کلیدواژگان: انگشت نگاری، ردیاب ها، رسوب، مدل های ترکیبی، تنگ بستانک
  • معصومه بحری، محمدتقی دستورانی صفحات 37-57
    علاوه بر تغییر اقلیم، تغییر کاربری اراضی به عنوان یک عامل جانبی اثرات مهمی بر سیلاب دارد. لذا پیش-بینی اثر این دو پارامتر بر وضعیت سیلاب دهه های آتی، راهگشای مقابله با این پدیده خواهد بود. هدف از مطالعه حاضر پیش بینی وضعیت هیدرولوژیکی حوزه آبخیز اسکندری در دهه آتی تحت اثر تغییر اقلیم و تغییر کاربری اراضی می باشد. جهت بررسی تغییرات اقلیمی دهه 2020، برونداد مدل HadCM3 تحت سناریوهای A2 و B1 توسط مدل LARS-WG ریزمقیاس گردید. پس از بررسی تغییرات کاربری-اراضی گذشته، دو سناریو جهت پیش بینی تغییرات آن در آینده طراحی شد. در انتها با تغییر هایتوگراف بارش و کاربری اراضی در مدلHEC-HMS که برای دوره گذشته کالیبره و اعتبارسنجی شده، اثر تغییر اقلیم و کاربری اراضی بر سیلاب منطقه مطالعاتی مورد بررسی قرار گرفته شد. نتایج نشان دهنده افزایش 2/7 تا 9/10 درصدی بارش متوسط سالانه دهه 2020 می باشد. افزایش توامان دمای حداقل و حداکثر منطقه مطالعاتی در تمامی ماه ها موجب افزایش 82/0 تا 02/1 درجه سانتی گرادی دمای متوسط سالانه خواهد شد. افزایش دبی اوج و حجم سیلاب در ماه های مارس، اکتبر و فوریه و کاهش آن در ماه آوریل پیش بینی شده است. به طوری که در صورت تغییر کاربری اراضی همراه با تغییر اقلیم این افزایش شدیدتر خواهد بود.
    کلیدواژگان: ریزمقیاس نمایی، سیلاب، HadCM3، HEC، HMS، LARS، WG
  • سید حسین میرموسوی، حدیث کیانی صفحات 59-72
    اقلیم، وضعیتی کلی از شرایط هوای غالب یک مکان مشخص بر اساس آمار بلندمدت است. تنوع عناصر اقلیمی در تعیین اقلیم یک ناحیه موثر بوده و باعث شکل گیری اقلیم های متنوع و متفاوت می شود. افزایش انتشار گازهای گلخانه ای و به دنبال آن تغییرات اقلیمی و گرمایش جهانی پیامدهای بسیاری برای کره زمین داشته است. ازجمله این پیامدها، بخصوص برای مناطقی که در کمربند گرم و خشک دنیا قرار گرفته اند، افزایش سطح پوشش اقلیم خشک و نیمه خشک است. در این مطالعه طبقه بندی اقلیمی کوپن برای کشور ایران در سال 1975 با طبقه بندی حاصل از خروجی مدل جوی-اقیانوسی MIROC برای سال های 2030، 2050، 2080 و 2100، تحت 2 سناریوی A1B و A2، که در گزارش چهارم IPCC آمده، مقایسه شده است. طبقه بندی های حاصل از خروجی مدل روند رو به رشد اقلیم گروه B که نماینده اقلیم خشک و نیمه خشک در طبقه بندی کوپن است و کاهش تنوع اقلیمی را نشان می دهند. همان طور که در نقشه ها ملاحظه می شود و بر اساس وسعت تحت پوشش این نوع اقلیم طی سال های آتی، افزایش اقلیم Bwh که آب وهوای گرم و خشک را نشان می دهد، به وضوح قابل مشاهده است. این افزایش به گونه ای است که در سال 2100، شاهد پوشش بیش از 95 درصد مساحت کشور توسط این اقلیم بر اساس هر دو سناریو هستیم. همچنین وسعت و تنوع مناطق تحت پوشش اقلیم معتدل (اقلیم گروه C) و اقلیم سرد (اقلیم گروه D ) در کشور به کمتر از یک درصد مساحت کشور خواهد رسید.
    کلیدواژگان: تغییر اقلیم، طبقه بندی اقلیمی، گرمایش جهانی، مدل MIROC
  • طاهره صادقلو، یاسر عربتیموری، اسماعیل شکوری فرد صفحات 73-100
    مخاطرات طبیعی یک چالش عمده در نواحی روستایی است و کنترل آن در روستا از اهمیت زیادی برخوردار است. با توجه به این مسئله هنوز عرصه های روستایی کشور از یک مدیریت فراگیر بحران برخوردار نبوده و سالیانه تعداد زیادی از ساکنان نواحی روستایی کشور در اثر سوانح طبیعی و غیرطبیعی دچار خسارات و تلفات جانی و مالی می شوند. روستاها و اهالی آن به عنوان پایه اصلی در مدیریت بحران با دانش و آگاهی، پیش بینی، آمادگی و بازسازی مناسب، نقش جدی در کاهش خسارات و تلفات مخاطرات خواهند داشت. پژوهش حاضر در بهار 1395، با هدف سنجش سطح دانش و آگاهی روستاییان درباره مدیریت بحران خشکسالی انجام شد. برای رسیدن به هدف پژوهش از روش شناسی توصیفی- تحلیلی از طریق شیوه مطالعه اسنادی و پیمایشی (پرسشنامه محقق ساخته) استفاده شد. جامعه آماری پژوهش را 260 نفر از خانوارهای روستایی دهستان میان خواف شهرستان خواف تشکیل داده اند. برای جمع آوری داده ها از روش نمونه گیری تصادفی طبقه ای با ابزار پرسشنامه محقق ساخته بر اساس شاخص ها و مولفه های ابعاد 4 گانه دانش مدیریت بحران خشکسالی از ادبیات نظری استفاده شد. پایایی ابزار اندازه گیری با محاسبه ضریب آلفای کرونباخ (0.784)، تایید شد. نتایج و یافته های این پژوهش حاکی از آن است که خانوارهای روستایی نمونه در برخورداری از مولفه های ابعاد چهارگانه دانش مدیریت بحران و در کل دانش روستاییان درباره مدیریت بحران خشکسالی، پایین تر از سطح مطلوب میانگین عددی 3 قرار دارند. همچنین با استفاده از مدل اولویت بندی کوپراس، بین روستاهای مورد مطالعه در خصوص برخورداری از دانش مدیریت بحران خشکسالی رتبه بندی انجام گرفت که روستای فایندر با بیشترین امتیاز در رتبه اول و روستای وراب در رتبه دوم و روستای مهاباد در پایین ترین رتبه قرار دارند.
    کلیدواژگان: دانش و آگاهی، بحران، مدیریت بحران، خشکسالی، دهستان میان خواف
  • مجید حاجی بابا، محسن شریفی صفحات 101-122
    سازمان های نیازمند به مراکز بزرگ داده بایک تصمیم بسیار مهم در زمینه یافتن مناسب ترین مکان جغرافیایی مواجه هستند. شناسایی، ارزیابی و تعیین مختصات جغرافیایی یک مکان مناسب، به معیارها و پارامترهای مختلف و بعضا متاثر از یکدیگر وابسته است که تصمیم گیری مدیران را برای یافتن مناسب-ترین مکان بسیار پیچیده و مشکل می سازد. برای اولین بار در ایران، این مقاله به بررسی تاثیر معیارهای حوادث طبیعی در جایابی و ارزیابی گزینه های در دسترس و مناسب برای میزبانی یک مرکز داده ملی در گستره جغرافیای کشور ایران می پردازد. معیارهای حوادث طبیعی در نظر گرفته شده شامل معیارهای خشکسالی، طوفان شن، طوفان گرد و غبار، سیل، زلزله و آتشفشان می باشند. نتایج این تحقیق با استفاده از رای گیری اکثریت نشان می دهد استان های سیستان و بلوچستان، کرمان و بوشهر پرحادثه خیزترین و استان های کردستان، چهارمحال بختیاری و قزوین کم حادثه خیزترین استان های کشور از منظر حوادث طبیعی برای برپایی مرکز داده هستند. بر اساس نتایج این بررسی، یک نرم افزار رایانه ای تولید شده است که اوزان معیارهای حوادث طبیعی را که با کمک متخصصین و طی یک فرآیند سلسله مراتبی مشخص شده اند، بعنوان ورودی اخذ کرده و سپس با استفاده از مکانیزم رای گیری اکثریت، نواحی جغرافیایی مناسب یک مرکز داده را به ترتیب الویت پیشنهاد می دهد. با استفاده از این نرم افزار و وزن دهی معیارها با کمک متخصصین، نشان داده می شود که استان های چهارمحال بختیاری، کردستان و مرکزی مناسب ترین و استان های بوشهر، کرمان و آذربایجان شرقی نامناسب ترین استان ها از منظر حوادث طبیعی برای برپایی مرکز داده هستند.
    کلیدواژگان: مرکز داده، جایابی، حوادث طبیعی، رتبه بندی استان ها
  • بهروز ساری صراف، علی اکبر رسولی، آذر زرین، محمد سعید نجفی صفحات 123-140
    از عوامل تاثیرگذار بر تغییرات بودجه تابشی جو، هواویزها هستند که به طور مستقیم و غیر مستقیم سامانه اقلیم و چرخه هیدرولوژی را تحت تاثیر قرار می دهند. در این مطالعه به شبیه سازی اثرات تابشی و مستقیم گرد و غبار بر سامانه اقلیم در منطقه خاورمیانه و با تاکید بر غرب ایران پرداخته شده است. بدین منظور از مدل WRF-CHEM و طرحواره هواویز GOCART استفاده شده است. مدل تحت دو شرایط فعال و غیر فعال بودن اثرات تابشی هواویز و برای رخداد 12 تا 15 آوریل 2011 اجرا شده است. نتایج این مطالعه نشان می دهد که این طرحواره در شبیه سازی طوفان های گرد و غبار در منطقه خاورمیانه دارای عملکرد قابل قبولی است. اثرات تابشی گرد و غبار در منطقه خاورمیانه نشان می دهد که وجود این ذرات باعث کاهش تابش موج کوتاه به میزان (Wm-2) 50- و افزایش تابش موج بلند به میزان (Wm-2) 5 و همچنین کاهش تابش خالص (Wm-2) 46- در سطح زمین در متوسط منطقه می شود. چنین شرایطی منجر به کاهش دما در بخش زیرین جو، و کاهش شار گرمای محسوس، شار گرمای نهان در سطح زمین در مناطق تحت تاثیر گرد و غبار می شود. از دیگر اثرات وجود این ذرات، افزایش فشار سطحی و همچنین کاهش تابش زمینتاب در بخش فوقانی جو است که افزایش دما را در بخش میانی جو نشان می دهد.
    کلیدواژگان: گرد و غبار، واداشت تابشی، گرمایش و سرمایش، WRF-CHEM
  • مهدی دوستکامیان، اسماعیل حقیقی، رضا بور بوری صفحات 141-162
    هدف از این مطالعه، شناسایی پهنه های گرم و سرد دمایی و تغییرات آن ها طی دوره های مختلف است. برای این منظور آمار دمای روزانه برای 238 ایستگاه سینوپتیک طی دوره آمار 1341 تا 1390 از سازمان هواشناسی کشور استخراج گردیده است. برای شناسایی پهنه های دمایی سرد و گرم دوره آماری را به پنج دوره مساوی تقسیم کرده ایم و سپس با استفاده از روش های آماری چند متغیره تحلیل خوشه ایو به منظور اعتبارسنجی پهنه های سرد و گرم دمایی از شاخص های نظیر، شاخص اعتبار سنجی دیویس-بولدین (Davies–Bouldin index)، شاخص سیلهوتی (Silhouette Index) و تحلیل ممیزی استفاده شده است. نتایج حاصل از این مطالعه بیانگر این است که پهنه های گرمای دمایی ایران به سمت دوره های اخیر علاوه بر اینکه به لحاظ گستره مکانی به سمت عرض های بالاتر (به سمت عرض های شمالی و تقریبا 2/3 درصد) کشیده شده است نسبت به دوره های اخیر 3/1 درجه سانتی گراد افزایش داشته است. در حالی که پهنه های دمایی سرد ایران به سمت دوره های اخیر علاوه بر اینکه از وسعت مکانی آن ها کاسته شده است مقدار دمای آن ها هم افزایش قابل محسوسی داشته است به طوری که میانگین پهنه های سرد دمایی ایران در دوره اول (1341-1350) با گستره 4/26 درصد دارای دمایی 7/12 درجه سانتی گراد بوده است که در دوره پنجم (1390-1381) این گستره به 8/25 و دمای 4/13 درجه سانتی گراد رسیده است که بیانگر افزایش 7/0 درجه سانتی گراد دمای پهنه های سرد می باشد. نتایج به دست آمده از شاخص های اعتبار سنجی دیویس-بولدین، شاخص سیلهوتی و تحلیل ممیزی آمده نشان داد که به طورکلی پهنه های سرد و گرما ایران بالای 98 درصد در گروه مربوط به خود قرار داشتند.
    کلیدواژگان: خوشه بندی، شاخص اعتبار سنجی دیویس- بولدین (DBI)، شاخص سیلهوتی (SI)، تحلیل ممیزی، دما
  • مسعود سیستانی بدویی، حسین نگارش، صمد فتوحی صفحات 163-182

    مخاطرات سیلاب یکی از مهم ترین و پرحادثه ترین مخاطرات طبیعی ایران می باشد که در سال های اخیر تکرار و شدت وقوع آن بیشتر شده است. شدت این مخاطره در حوضه آبریز گابریک به دلیل موقعیت جغرافیایی، شرایط خاص اقلیمی، زمین شناسی و عوامل حوضه ای بیشتر بوده و همه ساله حجم عظیمی از جریان سیلاب باعث تخریب اماکن مسکونی، اراضی کشاورزی و خسارات جانی و مالی زیادی می گردد. منطقه مورد مطالعه، یکی از حوضه های آبریز سواحل جنوب شرق ایران واقع در شرق استان هرمزگان بوده که با هدف کاهش خسارات جانی و مالی ناشی از مخاطره سیلاب در سکونتگاه های موجود در حوضه، به صورت تجزیه وتحلیل آماری، پیمایش میدانی و سنجش ازدور اقدام به شناسایی و تهیه نقشه پهنه بندی مناطق سیل گیر گردیده است. در این تحقیق با استفاده از فنون مختلف، پارامترهای موثر در وقوع سیلاب شناسایی و با به کارگیری مدل AHP در سیستم اطلاعات جغرافیایی، نقشه ای با دقت بالا تهیه شده است. نتایج حاصل از این پهنه بندی گویای آن است که مناطق با خطر بالا و بسیار بالا مجموعا 4/23 درصد مساحت حوضه را تشکیل داده که نشان از سیلابی بودن پهنه های وسیعی از این حوضه به خصوص در مناطق پست نیمه جنوبی است که از دلایل اصلی این وضعیت، بارندگی های بسیار شدید لحظه ای، نفوذپذیری کم، فرسایش پذیری زیاد و شیب زیاد ارتفاعات می باشد؛ بنابراین به منظور کاهش و مهار این مخاطره و بهبود شرایط منطقه، اجرای طرح های آبخیزداری و احداث سد لازم و ضروری است.

    کلیدواژگان: حوضه آبریز گابریک، مخاطرات سیلاب، پهنه بندی، هرمزگان، زمین آمار، GIS
  • زینب تیموری یانسری، سید رضا حسین زاده، عطاالله کاویان، حمیدرضا پورقاسمی صفحات 183-204
    زمین لغزش، یکی از مهم ترین خطرات ژئومورفولوژیکی با خسارات اکولوژیکی و اقتصادی قابل توجه است. منطقه مورد مطالعه به دلیل شرایط فیزیوگرافی و آب وهوایی از مناطق حساس و در معرض خطر زمین لغزش محسوب می گردد. پژوهش حاضر با هدف تعیین عرصه های حساس به وقوع زمین لغزش با استفاده از شاخص انتروپی شانون در حوزه آبخیز چهاردانگه (استان مازندران) صورت پذیرفته است. به این منظور، ابتدا نقشه پراکنش زمین لغزش منطقه با استفاده از تصاویر گوگل ارث و بازدیدهای گسترده میدانی تهیه گردید. نقشه های عوامل تاثیرگذار بر وقوع زمین لغزش شامل درجه شیب، جهت شیب، انحنای سطح، انحنای نیم رخ، طبقات ارتفاعی، شاخص رطوبت توپوگرافی، شاخص وضعیت توپوگرافی، شاخص پوشش گیاهی تفاضلی نرمال شده، کاربری اراضی، زمین شناسی، فاصله از گسل، فاصله از شبکه آبراهه، فاصله از جاده، تراکم گسل، تراکم زهکشی و تراکم جاده در محیط نرم افزار ArcGIS تهیه شد. نتایج اولویت بندی عوامل موثر با استفاده از شاخص انتروپی نشان داد که لایه های ارتفاع، درجه شیب، انحنای سطح و کاربری اراضی بیشترین تاثیر را بر رخداد زمین لغزش های منطقه، داشته اند و 05/51 درصد منطقه مورد مطالعه در طبقه حساسیت زیاد و خیلی زیاد نسبت به وقوع زمین لغزش قرار دارد. همچنین ارزیابی نقشه حساسیت تهیه شده با استفاده از منحنی ROC و 30 درصد نقاط لغزشی بیانگر دقت خوب مدل مذکور برای منطقه مورد مطالعه است.
    کلیدواژگان: پهنه بندی زمین لغزش، مدل انتروپی شانون، منحنی تشخیص عملکرد نسبی، حوزه آبخیز چهاردانگه
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  • Siavash Shayan, Ebadollah Ghelichi, Mojtaba Yamani Pages 1-16
    IntroductionIn many engineering activities awareness from geomorphologic active processes in relation to the construction of roads, dams, buildings and bridges is an essential element that should be considered. The road weakness could be classified in many aspects such as climatic, topographical, geological and hydrological aspects. Constructing the transportation networks that pass through dynamic environments, finally leads to some changes in physical environments that if this changes pass over the thresholds, it may lead to environmental unbalance and also lead to some bad socio-economic feedbacks. The geomorphologic hazards are the main agents of threat to the engineering and construction activities. Awareness of geomorphologic processes and hazards is one of the main essential things in road construction. These hazards usually cause traffic problem, car accidents, and also financial losses and fatality. For example, the destruction of a large portion of northern Haraz road in Iran by a 5/5 magnitude (6/ 2 magnitude of external sources) earthquakes in 8th June of 2004.
    Study AreaThe study area is the main road between the city of Karaj to Kandovan tunnel and adjacent regions, which is part of major Karaj - Chaloos roads and one of the important roads of Iran in the north and north west of Tehran province. The geographic location of the study area is between 51 to 51 degrees and 37 minutes east longitude and between 35 degrees 18 minutes to 36 degrees 15 minutes of north latitude.
    Material and MethodsThis study is an experimental - application of conceptual models – which is based on mathematical and fieldwork conceptual models. For this purpose, we collect the data using library resources and web-based sources such as internet websites. We used 1:100,000 geologic maps and 1:50,000 topographic maps, LANDSAT and P5 images, and field surveys (devices and digital cameras). Then, using Google Earth software, Excel, Photoshop, ERDAS and GIS, we prepare data layers. By field work and measurements and photography, we gathered evidences for analysis and conclusions, and then by a deep understanding of active morphodynamic mechanisms and morphogenesis action, we prepared a map for geomorphologic hazards.
    Results and DiscussionAccording to high topographic gradient (elevation gradient is relatively large, steep, slopes due to being stuck in the snow), that highly guarantees, morphogenesis and morphodynamic process therefore the erosion process occurred continually. In study area the first factor that causes hazards is differences in lithology, which play a fundamental role in the formation of rough shapes or topography. The index VF=3% indicates high tectonic activity of forces in the region. The freeze-thaw and mechanical weathering caused rocks to have fissures and cracks in the roadbed and surface. Morphologic changes in the road beside human activities, made imbalances and increased instability and degradation of the natural environment. Based on field studies, many tectonic forces in the region (folding, along with faults), and river channel erosion (washing), such as loss material movements, debris flows, landslides, snow and rock avalanches, cryoclastic and human morphogenesis are important geomorphologic active factors along the road.
    ConclusionGeomorphologic processes in many engineering research related to the construction of roads, bridges, dams, and buildings is essential. Road engineers should understand and learn more and more about geomorphologic processes. So, before they make any plan and construct a way, they should understand geomrophologic factors affecting roads and make appropriate designs in relation to land use based on geomorphic indicators.
    Keywords: Applied geomorphology, Road transportation, Cryoclastic, Human or morphogenesis
  • Ahmad Nohegar, Mohammad Kazemi, S.Javad Ahmadi, Hamid Gholami, Rasol Mahdavi Pages 17-35
    IntroductionSediment yields effects are often termed on-site and off-site impacts, increasingly in watersheds (Palazon, Gaspar, Latorre, Blake and Navas, 2015). The sediment fingerprinting method has provided a direct and successful approach to quantify sources of sediment (Chen, Fang and Shi, 2016). Sediment fingerprinting approaches offer the potential to quantify the contribution of different sediment sources, evaluate catchment erosion dynamics, and develop management plans to tackle, among other problems, reservoir siltation (Palazon et al, 2015). Land use changes are crucial to understanding the evolution of sediment load and discharge dynamics (Wang, Chen, Fu and Lu, 2014). The present study aims to compare the results of several fingerprinting models, soil erosion features, and map and direct field measurements of soil erosion.
    Study area:Our study was conducted in the Tange Bostanak catchment (30°16′ to 30°25′ N and 52°03′ to 52°13′ E), in the Southern Zagros mountains, 80 km Northwest of Shiraz, Iran.
    Material and MethodsSampling and Data Collection
    Potential sediment sources were identified by examining the main land use types within the study catchment, which are dominated by four main groups: rangelands, forests, moderate forests, farming and gardens. Forty three representative samples were collected from these potential sources at different locations within the study catchment. In order to remove bias associated with grain-size effects, only the 63 μm soil and sediment fraction, obtained by dry sieving, was taken for tracer analysis. Total concentrations of Ba, Cd, Co, Cr, Cu, Li, Mn, Ni, P, Si, Sr, Ti, C, N, Zn, 87Sr. 86Sr, 143Nd. 144Nd, Sr and Nd were measured by ICP-Mass after digestion of 3 gr of the soil samples with aqua regia (HCl–HNO3; 3:1) for 2 hours. In order to assess the validity of the analytical results, accuracy
    and precision were calculated.
    Source Discrimination/Discriminant Analysis
    The statistical analysis employed to identify a composite fingerprint which is capable of discriminating between potential sources was done in two steps. The first step involved testing the discrimination of potential sources by the fingerprint properties using the Kruskal–Wallis test. Second, we applied stepwise multivariate discriminant function analysis (DA) to select the optimum subset composition of geochemical tracers for maximizing discrimination (Collins, Walling, Webb and King, 2010).
    To identify outliers, was calculated the squared Mahalanobis distance, or the multivariate distance of each sample from the centroid of all samples belonging to a given category in the multidimensional space.
    Sediment Sources Apportionment and Mixing Models
    In geochemical tracing studies the relative contribution of source material to suspended sediment is usually estimated using a multivariate mixing model. The literature describes many different mathematical forms of mixing models. In all mixing models, the objective is to determine the source component proportions (x) in the suspended sediment samples by minimizing the errors. Five mixing models and their modifications to estimate contribution of sources were used.
    (Slattery, Walden and Burt, 2000),
    (Collins, Walling and Leeks, 1997),
    (Devereux, Prestegaard, Needelman and Gellis, 2010),
    (Collins et al., 2010),
    (Motha, Wallbrink, Hairsine and Grayson, 2004)
    where: ci = concentration of fingerprint property (i) in sediment samples; Sij = concentration of fingerprint property (i) in source category (j); X j = percentage contribution from source category (j); Z j = particle size correction factor for source category (j); Oj = organic matter content correction factor for source category (j); Wi = tracer discriminatory weighting or tracer specific weighting; SVji = weighting representing the within-source variability of fingerprint property (i) in source category (j); VARij = variance of the measured values of tracer i in source area j; mj = the total number of samples for an individual source; n = number of fingerprint properties; and m = number of sediment source categories. In sediment fingerprinting studies, to find the best optimum sediment contribution minimizing mixing model errors, Collins et al. (2012) proposed a revised modeling approach comparing the results of local optimization to determine the uncertainties with the following goodness of fit GOF equation and also used RMSE index to select the best mixing models.
    Results and DiscussionSoil erosion and sediment yield are among the most destructive phenomena that cause a lot of damage in different regions. However, in order to combat this phenomenon and soil conservation projects, it is needed to be aware of the location of sediment sources in the region. Sediment fingerprinting technique based on geochemical tracers, organic, isotopic ratios, as well as useing various mixing models lead to the recognition and the contribution of different sediment sources in an area. In this study, using the optimum combination of organic and rare tracers to separate the different sources and then determine contribution of this erosion and sediment yield resource using Collins (1997), Collins Modified (2010), Motha (2004), Landwehr (2010), and Slattery (2000) models. In this case, to determine the best model GOF index and matching results with actual measurements of the sediments and erosion amount based on BLM model were used. The result were analyzed by discriminant analysis showed compounds of C, Cu Si, and Ti were considered as tracer and M Collins mixing model with indices GOF, 99.9 was selected as the best model. Measurement results showed that sedimentation rates of different land uses, pastures with relative importance of 3.4 is the priority in management of soil conservation. Mixing models showed the highest proportion in sediment and erosion basins on weak and degraded rangelands area is by 57.04 area percentage and 64.9 contribution percent in field measurements. Cultivations have minimal role in sediment yield of Tange Bostanak watershed. Results showed Motha model with a 0.924 correlation coefficients had the smallest difference with actual values of sediment contributions. The differences in the results of fingerprinting technique and field measurement techniques referred to their quantitative or qualitative approaches and not considering sediment delivery ratio concept and other sediment transition processes. It clearly confirmed the necessity of simultaneous use of all aforesaid techniques to get access to reliable results and to choose the better mixing models in catchments.
    ConclusionSoil erosion and sediment yield are among the most destructive phenomena that cause a lot of damage in different regions. However, in order to combat this phenomenon and soil conservation projects, it is needed to be aware of the location of sediment sources in the region. Sediment fingerprinting technique based on geochemical tracers, organic, isotopic ratios, as well as using various mixing models lead to the recognition and the contribution of different sediment sources in an area. In this study, using the optimum combination of organic and rare tracers to separate the different sources and then determine contribution of this erosion and sediment yield resource using, Collins (1997), Collins Modified (2010), Motha (2004), Landwehr (2010), and Slattery(2000) models. In this case, to determine the best model GOF index and matching results with actual measurements of the sediments and erosion amount based on BLM model were used. The results were analyzed by discriminant analysis and showed compounds of C, Cu Si, and Ti were considered as tracer and M Collins mixing model with indices GOF and RMSE, 99.9 and 2.07 were selected as the best models. Measurement results showed that sedimentation rates of different land uses, pastures with weak and moderate cover percentage and gardens with relative importance of 3.04 and 7.72 are prior in the management of soil conservation. Mixing models showed the highest proportion in sediment and erosion basins in the rangelands area is about 16.75 percentage and 57.04 contribution percent and the cultivation has minimal role in sediment yield of Tange Bostanak watershed. Moreover, results showed that Motha model with a 0.924 correlation coefficients had the smallest difference with actual values.
    Keywords: Fingerprinting, Tracer, Sediment, Mixing Models, Tange Bostanak Watershed
  • Masoumeh Bahri, Mohammad Taqi Dastorani Pages 37-57
    IntroductionClimate change is a change in the statistical distribution of weather patterns which can last for an extended period of time. Climate change may refer to a change in average weather conditions, or in the time variation of weather around longer term average conditions. Changes in temperature and precipitation patterns under climate changes have serious impacts on the natural disaster, especially in arid regions. Flood is one of the most important disasters on which climate change has effect. The primary effects of flood include loss of life, damage to buildings and other structures including bridges, sewerage systems, roadways, and canals. Floods can also frequently damage power transmission and sometimes power generations. Damage to roads and transport infrastructure may make it difficult to mobilize aid to those affected or to provide emergency health treatments. Flood waters typically inundate farm land, making the land unworkable and preventing crops from being planted or harvested, which can lead to shortages of food both for humans and farm animals. In addition to climate change, the land use changes, as an ancillary factor have impact on floods. Thus, evaluation of the impacts of climate change and land use change on flood situation in the coming decades will open a new way to deal with this phenomenon.
    The first comprehensive review of climate change and its effects on flooding and runoff was reported by the Intergovernmental Panel on Climate Change.
    Study AreaStudy area is Eskandari basin that is located in west of Isfahan province. Latitude and longitude are 33 °11´to 32° 42´ N and 50° 40´ to 50° 02´. This area is crucial because it is the water resource of Isfahan city.Zayandehroodriver flows in this catchment.It starts in Zard-Kuhsubrange of Zagros Mountains in Chaharmahal and Bakhtiariprovince. It flows 400 kilometres (249 mi) eastward before ending in the Gavkhouni swamp, a seasonal salt lake,southeast of Isfahan city.The water ofZayandehrood gives life to the people of central Iran mainly in Isfahan.
    Material and MethodsThis research has three phases;the climatic phase, land use phase and hydrologic phase.In the first phase, to study the effects of climate change in the2020s in Eskandari basin, daily temperature (minimum and maximum) and sunshine along with daily precipitation (1965-2008) were downscaled with LARS-WG. LARS-WG is a model simulating time-series of daily weather at a single siteunder both current and future climate conditions. These data are in the form of daily time-series for a suite of climate variables, namely, precipitation (mm), maximum and minimum temperature (°C) and solar radiation (MJm-2day-1).It utilizes semi-empirical distributions for the lengths of wet and dry day series, daily precipitation and daily solar radiation. The semi-empirical distribution Emp= { a0, ai; hi, i=1,.…,10} is a histogram with ten intervals, [ai-1, ai), where ai-1
    Keywords: Downscaling, Flood, HadCM3, HEC-HMS, LARS-WG
  • Seyyed Hossein Mirmousavi, Hadis Kiani Pages 59-72
    IntroductionClimate, is the general condition of the prevailing weather conditions in a specific location based on its long-term statistics. The diversity of climatic elements affects determining the climate of a region and forms a variety of climates. Comparing the characters of the recorded weather in different places of the earth reveals significant differences in the surface of this planet. Thus, every place has unique characteristics. Comprehending the weather and ultimately climate has been an important consideration for human beings since a long time ago and has a significant importance in today’s human life. Comprehending the natural characteristics of each region, particularly, climate, plays a major role in land use planning. In order to achieve this objective, climatic zoning to identify different areas of climate seems to be necessary. From a geographer's point of view, climatic zoning means organizing and categorizing the zones climatically in a way that each region has similar climatic characteristics. On the other hand, the increase in emissions of greenhouse gases and subsequently climate change and global warming have had many consequences for the planet. Particularly, the areas which are in the warm and dry belt, for the growth of the dry and semi-dry climate’s coverage is increasing. Climate change is a long-term and non-recoverable climatic condition which occurs over a period of tens or millions of years in an area's climate. The recorded data suggests that from 1901 to 2012, the temperature of the earth’s surface and the temperature of oceans have increased averagely 0.89 degrees Celsius. Therefore, changes in the climate of different parts of the world and the displacement of the existing boundaries of the climatic zones are expected. Due to the wide geographic latitudes and the existence of different local conditions in different regions, Iran has a wide climatic diversity and this issue has raised the importance of climatic zoning in this country. On the other hand, due to Iran’s presence in the warm and dry belt of the world, the country is affected by the global warming and climate change issues. Therefore, the study of new climate conditions in the country, as well as a survey on the possible movements of the existing boundaries of the climatic zones will be necessary.
    Material and MethodsIn this study, the information from Copen’s classified data for Iran, which are turned to maps, using the ArcGis software, using the year 1975 as a base year and the simulated data, using the atmosphere-ocean MIRCO-H model for simulation, which is presented in the fourth report IPCC (AR4), under two scenarios A1B and A2, has been used for the years 2030, 2050, 2080 and 2100. Then, Copen’s climate classification for Iran in 1975, is compared to the classification of atmosphere-ocean MIROC output for the years 2030, 2050, 2080 and 2100 under the two scenarios A1B and A2. This model, with the cooperation of the National Institute for Environmental Studies (NIES), the Oceanic-Pacific Institute of Oceanography (CCSR) Tokyo University and Japan Marine and Land-Based Science and Technology Agency for predicting the 21st century climate, is designed with a relatively high degree of complexity and Resolution. Compared with HadCM3 models (With an atmospheric resolution of 3.75 ° 2.5 ° and oceanic 1.25 ° x 1.25 °), it has a higher resolution. Predictive atmospheric variables in this model include temperature, north and east wind components, and surface pressure, and predictive oceanic variables include the velocity of orbital and meridian wind, temperature, salinity, and altitude.
    Results and DiscussionIran’s climate in 1975 contains three primary groups, namely, B (dry and semi-dry with a lack of precipitation), C (temperate with mild winters) and D (cold, cold winter, the coldest month temperature is lower than 3 ° C) and sub-categories of the three groups. As can be seen in Figure 2, climate group B is covering most of the country’s area. Bwh (T≥18˚c) climate, which represents the warm and dry climate, covers the widest area of the country (641043.7 km 2) and includes large parts of central Iran, South, South East, and South West of the country, which is about 40% of the country’s area. Moreover, regarding the Bsk climate, which is semi-dry and cold and indicates the extent of 22% in the North East, the eastern slopes of the Zagros and Alborz and Bwk climate, (cold and dry climate) 4.15 percent of the central country’s margin areas and parts of East and Southeast have been placed in next categories. In our country temperate climate from group C mostly appears in the Csa group form which represents the Mediterranean climate in our country, covering about 6 percent of the country’s area, including regions of North, Northwest, West and the western foothills of the Zagros. The cold climates Group D, appears in the mountainous regions of the West and North West of the country which covers 12% of the country’s area. Considering the climate change and global warming issues, which have been effected in the recent years, many models and methods have been used to rebuild and predict the global climate for the coming years. Although these models still have weaknesses and shortcomings to predict the future of the earth accurately, they also have much strength that makes them credible to predict and understand the future climate of the planet. The use of the output of atmosphere-ocean that coupled general circulation models are increasing as the most credible tool in climate change research. Various versions of the (AOGCM) models have been presented, including the 4th International Climate Change Board Assessment Report (AR4) (2007).
    The classifications based on the model’s output indicates a growing trend in group B, which represents the dry and semi-dry, in Copen’s classification. Considering the outspread area covered by this type of climate over the coming years, climate Bwh (hot and dry climate) is increasing, such an increase that in 2100, more than 95 percent of the country is covered by this type of climate based on both scenarios. While temperate climate group c, which represents the Mediterranean climate in Iran, just appears in parts of coastal North and North West of the country, group D includes very narrow cold climate areas of the mountainous areas of the North West. In general, the results from the model’s output, reveals a gradual increase in the size of the area covered by the warm and dry climate and a decrease of the cold and temperate climate in Iran over the coming years until 2100. Thus, we can see the adverse effects of climate change and global warming and the shifting borders of the Copen’ climate categories in the country.
    Keywords: Climate change, Climate classification, Global warming, The model MIROC
  • Tahereh Sadeghloo, Yaser Arabteimuri, Esmaeil Shakuri Fard Pages 73-100
    IntroductionDoubtless, rural development is a multiple concept and has different dimensionsincludingeconomic, social and cultural (Ghadiri masoum, 2012: 2)and for getting to sustainable rural development considering all environmental, social, cultural, economic, physical, institutional, and managing aspectsis needed(Afrakhteh, 2012: 40). Meanwhile, attending to disasters and crisis that permanently create sudden changes and alterations in rural area is one of the main issues and problems of rural development. Crisis happening affect all parameters of sustainable development;therefore, crisis management has been counted as an essential step of sustainabledevelopment (Firoozi and et al, 2011: 97). In recent years, so many of rural communitiesin our country havefaced withclimaticchanges like earth warming and drought that cause agricultural damages, income decreasing, unemployment, and migration from rural to urban areas for finding job opportunities, or from anoptimistic viewpoint,changing the cultivation and production patternsthat need less irrigation and had increased rural vulnerability and unsustainability against disasters. Necessity of attending to disasters is the undeniable duty of crisis management organizations and foundations. Since the disasters and crisis usually causeto heavy and severe damage in vulnerable environments, in rural settlementswhichare counted as disastrous places, crisisand disasters haveheavy and wide damages (Riahi and et al, 2013: 2). Crisis management, as a practical and scientificexpertise,requiresskills, tools, and different factors whichawareness and knowledge are twoimportant requirements of them. Since in drought crisis, rural communities use different strategies for coping with disasters effects, and based on scientific studies, tact and intelligence chiefs in crisis is only possible through gaining knowledge, this study tries to measure and analyze the rural communities’ awareness and knowledge about drought crisis management a rural area inKhaf township. In this regard, the aims question of this researchis that: how much is the knowledge and awareness of villagers about drought crisis management in case study area?
    Material and MethodsThe present study has adescriptive-analyticalapproach and tries to examine and assessing the level of awareness and knowledge among rural householdsaboutdrought risk management in middle Khaf rural districtof Khaf township.This study include twomainsteps: 1) determining the index and indicators formeasuring the crisis management awareness and knowledge among rural people that had been done through archival research, and 2) a field study based on a survey method and collecting datathrough questionnaire. This researchermade questionnaire contains 64 items withfourdimensionsabout different aspect of crisis managements that were extracted from theoretical research frameworks. After designing thequestionnaire, gathereddata from 13 rural point as a case study area were analyzed bySPSS. There are 15 rural points invillage case study that two villages have less than20 households and wereexcludedfrom study. The sample size was chosenby Cochran formula and 260 rural households had been determined as the sample size.
    Middle Khaf Dehestanliesin central district of Khaf township in Khorasan Razavi province and according to the general population census in 2011, thepopulationwas estimated to be 8537 with 1991 householdsin 15 rural points. This Dehestan is located ineast and northern east ofTaybad Township and southof KhafTownship. Its height above sea level ranges from950 to 1270 meters. Average rainfall in KhafTownship is around 142.2 mm, which is about 83 percent far from world average rainfall,and 35percent from Iran’s average rainfall. Its weather is hyper dry, based on Demarton climatic classification. This Dehestanlike other parts of Khaf Townshiphasfaced withdrought and every year experience many social and economic losses and damagesfrom that.
    Results and DiscussionAfter gathering data,statistical methods and examinations had been usedfor dataanalyzing. In first step for analyzing and identifying the current situation of rural awareness about drought crisis management T-test statistical test was used. Based on the gainedresults, awareness and knowledge of rural community about drought management is lowerthan moderate mean (3) in the case study area, especially in twoimportant indicators- resources, namely,reaction provisionand incomereplacement,which werelower than other indicators too. This pointindicates the need to payserious attention to educating therural people as an initial loop during the eventand crisis occurrence and reconstruction. The following results were also gained:• The average of Knowledge and awareness about drought crisis management is generally 2.41 and 2.54 for individuals aged less than 30 years old and over 30 years old. It means that old people are more aware about drought in compare to youngest people.
    • The average of crisis management awareness and knowledge for different job, including thefarmers, ranchers, employees, students, and others are 2.43, 2.40, 2.38, 2.37 and 2.37, respectively. This result shows that rural people’s jobs had affected their knowledge and awareness about drought.
    • There is a negative meaningful relationship between rural household’s education and crisis management knowledge and awareness for drought. It means that with increasing the level of rural education, their awareness and knowledge about drought management is reduced.
    • There isno meaningful relationship between gender and rural knowledge and awareness about drought management.
    ConclusionNatural disasters are the main challenge in rural areas and theircontrol is a great purpose of sustainable development. Due to this, rural areas of our country do not have a comprehensive crisis management structure and every year a large number of residents in rural areas suffer from human and financial damages and losses of environmental disasters. As mentioned, awareness and knowledge promotion areimportant factors for coping with natural events damages in rural areas based on community based approaches of rural development. Result of the study shows that drought management awareness and knowledge among rural communities are notin a good and appropriate condition and is less than moderate level (lessthan 3). The result of research indicate the need to improve the awareness and knowledge of villagers and local population as a main stakeholders and actors of the community based approach to crisis management and development. The objective of crisis management knowledge is effortto identify and increase the level of rural awareness about different stages ofcrisis management and the activities thatlocal people should be aware of that, learn from it and act, accordingly. Today, with the emphasis on crisis management views such as social attitudes, many functions have been proposed for crisis managers.Inthe scope of macro space, management has been transferred to local communities whichincreases the need to improve the knowledge and awareness of local communities.
    Keywords: Knowledge, awareness, Crisis management, Drought, Middle Khaf Dehestan
  • Majid Hajibaba, Mohsen Sharifi Pages 101-122
    IntroductionThe importance of data center site selection according to different criteria and the protection of data and equipmenthas causedthe proximity to the business offices getting less important and there will be an opportunity for other cities to host the data centers.Thus, each organization when establishing a data center, must evaluate significantfactors in locating a national data center.
    In general, important factors in choosing a data center location include weather conditions, natural disasters such as floods and earthquakes, un-natural disasters such as war and terrorism, easy access to critical infrastructures such as communications, electrical power,and transportation and qualified people to work in the data center.
    Thenatural disasters in the developing countries have more impactsrather than developed countries. Since there is no specific study on the impact of natural disasters to locatingdata centers in Iran, in this article,we focus on the natural disasters criteria to locate a data center in Iran.Thisstudy attempts to evaluatetheimpact of this criteria on national data center and offerssome locations for them in Iran.
    Material anf MethodsIn this work, disastersare divided into five main categoriesincludingearthquakes, drought, storms, floods, and volcano, and then, they are evaluated separatelywith respect to Iran's climatic conditions.
    This study is applicable and prepared based on content analysis and statistical analysis. In this study, the effective criteriaon data centersite location in terms of natural disastersis investigatedto find the most desirable province to establish a data center in Iran.Then, provinces are ranked, respectively,as the most favorable to host the data center, according to specific criteria. Animpact factor or weight is added to each criteria using analytic hierarchy processbased on expert’ssurvey, which shows the importance of it from the IT standpoint.Finally, by obtaining the weighted averageand the use of majority voting, the best provinces to host anational data centerare presented respectively.
    results and DiscussionThe operation of a data center can easily be compromised by natural disasters. Natural disasters such as earthquake, volcano, storm, flood and drought are always a threat to a data center.It is commonly assumed thatthe probability of occurrence of these events is extremely low and their impact is not much if they happen.But generally, the location of a data center should be somewhere that is potentially far from these risks.
    Hence, for the first time in Iran, this paper investigates the effect of natural hazards criteria on locating options for hosting a national data center in the whole geography of Iran. Based on our investigation, a computer software is developed that uses these natural hazards criteria, as well as many other factors in mind, to automatically rank all provinces in Iran and their geographical coordinateswithin provinces that are suitable for data center location. Natural hazards criteria used include earthquake, drought, storm, flood, and volcano. An inference engine in the computer software takes in weights of natural hazards criteria that obtained from experts’ judgments and uses a hierarchical analytics processing, and then by a major voting mechanism, outputs its ranked recommended geographical areas.
    ConclusionIn this paper, by recognizingdata center site selection criteria, the natural disasters criteria are measured and their impact on a national data center is obtained with the help of experts. Finally, usingan analytic hierarchy process, a software is developed that receives weightsand ranks cities in terms of suitability for the establishment of a data center.
    The proposed ranking is just based on natural disasters. This is applicable for some data centers that do not have the security aspects, but depending on the type of data center operation, other criteria should also be considered.For example, if the aspect of national security of a data center is concerned, war and terrorism criteria can improve the rank of center townscompared toborder towns.
    To rank cities in this paper, a fixed distance is usedamong scores (a unit distance between 1 and 30, respectively). As a future work in this research a proper distance amongscores of cities for the final ranking can be expressed, and scores of cities are calculated according to their distance of criteria that was calculated individually for all cities to achieve higher accuracy in addition toa better illustration of the impact of their weights.
    Criteria measurementin this article is made by a province that is not a proper granularity to set up a data center. As a future work,we are going to measure these criteria for cities instead ofprovincesto reach to more accuracy.
    Keywords: Data center, Data center site locating, Natural hazards, Province ranking
  • Behruz Sari Sarraf, Ali Akbar Rasouli, Azar Zarrin, Mohammad Saeed Najafi Pages 123-140
    IntroductionDust storms frequently occur throughout the desert regions of the world, injecting large amounts of mineral dust aerosols into the atmosphere. Dust aerosols have a wide range of potential consequences for ambient air quality, global climate, atmospheric chemistry, and biogeochemical processes. Higher levels of particulate matter during dust storms can lead to serious health problems.
    Mineral dust aerosols from arid and semi-arid regions are important constituents of the atmosphere and climate system that influence the radiative budget of the earth directly and indirectly by acting as condensation nuclei for the formation of both, cloud droplets and atmospheric ice particles and thereby impacting microphysical and optical properties of clouds in both regional and global scales. Considering only the indirect effects, the ice phase has a particularly strong influence on cloud properties by affecting cloud lifetime and precipitation processes. Depending on their physical and optical properties as well as their chemical composition, aerosols exert a cooling or warming influence on the atmosphere and underlying surface.
    Every year, about 3000 trillion grams of dust are entrained into the atmosphere from arid and semiarid regions and the Asian deserts and Middle East are two of the largest dust-producing regions in the world. Regarding to the geographical location of Iran, it is frequently exposed to local and regional dust systems. Over the last decade, dust storm in the Middle East especially in the Arabian region (including Saudi Arabia, Iraq, Syria and Jordan) has significantly been increased and such condition injected annually millions grams of dust into the atmosphere and affects radiation budget and climate of this region. Thus, being in vicinity of vast deserts, the west and southwest of Iran are characterized by high-levels of dust events, which have adverse consequences on human health, ecosystems and environment. The aim of this study is to explore the radiative forcing and direct effects of dust storms events in the Middle East and west of Iran.
    Study AreaThe study area located in western Iran and including three Kermanshah, Ilam and Khuzestan provinces. The region bounded between 29˚ 58ʹ N to 35˚ 17ʹ N and 45˚ 20ʹ E to 50˚ 39ʹ E. The study area is geographically bounded by the high western Iran’s high Mountains on the West, and coasts of Persian Gulf on the south. Depending on the topographical features of the landscape, the climate of the region varies from north to south, such that there is a drier and warmer climate on the southern area compared to the middle and northern parts of the study area.
    Material and MethodsThe WRF-Chem model version 3.7 was applied to simulate the global distribution of mineral dust and its radiative forcing. The Weather Research and Forecasting with Chemistry (WRF-CHEM) model is the most advanced online coupled model in terms of the number of available schemes, complexity of the aerosol, and chemical schemes, as well as the coupling between gases, aerosols, and meteorology. The GOCART simple aerosol scheme used in this study only focuses on the simulation of dust particles and their impact on radiation.
    Simulation of mineral dust inthe Middle East from April 12 to 15 2011 and its impacton radiation fluxes over the domain with 30-km grid spacing is estimated using two simulations: a standard model that did not include dust aerosols feedback; and aninteractive experiment that included dust aerosols and theirfeedback to the atmosphere.Finally for validation ofWRF-CHEM simulation of mineral dust, the data fromaerosol products of AERONET (Aerosol Robotic Network) and satellite measurements, along with environmental observation close to dust sources had been used. For this, the hourly ground-based measurements (e.g., dust concentration, PM10 and PM2.5 in Iran’s environmental stations and AOD in AERONET measurements) and also satellite observations (e.g., MODIS and MISR) were used. Via these, the regional model deficiencies in the representation of the spatio-temporal distribution as well as optical properties (e.g., aerosol optical depth; AOD) of mineral dust had been identified.
    Results and DiscussionWe found that for simulation of mineral dust in the West Asia domain by the GOCART dust module, it is needed to make some changes in erosion maps and source codes. By these changes, the model will give the simulation closer to reality. By these changes, the diurnal variation of the simulated hourly PM10 mass concentration inAhwaz is qualitatively close to the hourly observations made by the Khuzestan Department of Environment. The model captures diurnal cycle of the observed PM10 concentration during most of the simulation period, although the model predictions overestimated PM10 concentration in time of maximum PM10 concentration. Totally coupling WRF model with GOCART aerosol scheme has a good performance in simulation of hourly PM10 mass concentration.
    Furthermore, thecomparison of the simulated aerosol optical depth (AOD) by GOCARTaerosol scheme and the observations in Solar Village site of the global AERONET Network show thatthe model has a good performance in simulation of (AOD). In the other hand, the model has a good performance in spatial distribution in case of dust storm in the Middle East.
    The spatial distributions fromApril 12 to 15, 2011 average of SW, LW,and net radiation (SW) dust direct effect at surface showthe SW DRE (direct radiative forcing) is mostly negative at the surface, reaching -50Wm-2.The average of surface SW DRFin western Iran is -36Wm-2 and tendsto cool the surface. The daily averaged surface LW DRE ismostly positive.
    The maximum average LW DREat the surface is 12Wm-2and LW average in areas that are affected by dustis 5Wm-2.At TOA, the maximum average valueof outgoing LW radiation(OLR) is -25Wm-2that the average in areas that are affected by dustis -15Wm-2which demonstrates warming of the TOA earthatmosphere system. At the surface, the net radiation DRE is negative in most of the region and such condition leads to surface cooling.
    The surface air temperatureover the majority of the study domain cools down in response tothe net dust radiative effect. The temperature changes by upto -1° K in Middle East. The instantaneous surface sensible heat flux decreases over the area that is affected by dust with an average value of -21Wm-2 in the presence of dust aerosolsover land. The value for surface latent heat flux is -2Wm-2in average of dusty region.
    ConclusionThe results of this study show that the model has a good performance in simulation of (AOD) and diurnal cycle of the observed PM10 concentration; however, the model predictions overestimated PM10 concentration in time of maximum PM10 concentration.
    The results of radiative forcing of dust storm in the Middle East show that mineral dust cause decrease of shortwave radiation and net radiation and increase of longwave radiation at the surface. Such condition leads to decrease on surface temperature and tendsto cool down the surface up to -0.6° K in western Iran. Additionally, the presence of mineral dust cause decrease of surface latent and sensible heat flux and temperature. Hence, dust directly influences the earth’s radiative budget and causes surface cooling. At top of atmosphere, presence of dust leads to decrease of OLR which causeswarming of the TOA earthatmosphere system. Some documents showed that dust storm in the Arabian Peninsula leads to decrease of surface shortwave radiation, increase of surface longwave radiation, and totally decrease of net radiation in the surface. In this study, we approved such results for the west of Iran.
    Keywords: Mineral dust, Radiative forcing, Cooling, warming, WRF-CHEM
  • Mehdi Doostkamian, Esmaeil Haghighi, Reza Bourbouri Pages 141-162
    IntroductionTemperature can be considered as one of the most important elements of the climate system to changes that can transform any local weather conditions. These changes can occur in many ways due to the heterogeneous distribution of solar energy inthe Earth's surface (Nazemosadat,2009). Several factors can affect the temperature of azone. Thus, thisstudy can reflect those factors. Location factors such as topography and latitude location as well as theinfluence of neighbors, atmospheric circulation systems, and many other factors have an undeniable role in the development of the temperature. It should be notedthat temperature or any other climatic element in each location will be similar to adjacent areas. In this case, it is obvious that the degree of similarity between samples ismore likely to be closer. Because, if there is a spatial structure, changes in the same area have a greater chance of influencing your space near to the outer space of their own (Hassanipak, 2009). The neighboring area knows that the formation of a climate temperature is of utmost importance.Therefore, it is important to know the neighborhoods that cause the formation of a climate of temperature. Generally, the main cause of temperature differences in different parts of the planet is the difference in angles of sunlight in different geographic latitudes, but if this factor is accepted as the only factor affecting temperature variations, temperature changes over the course of one year and in different years of regular course If it is not so in nature, and factors such as the topography of the area, the direction of the slopes, the soil cover, the distances or proximity to the water zones, and the regional and planetary atmospheric systems of this order will overcome. The climate and temperature hotbeds were less studied by climatologists, but these zones were considered by climate experts under other titles such as the identification of thermal waves (hot temperature zones) and cold waves (cold temperatures).
    Material and MethodsIn this study, to identify zones of warm and cold temperatures, daily temperature of283 daily synoptic stations of Iran’s Meteorological Organization has been extracted. This group of data interpolation values and the daily temperatures across the country between1961and2010(18183 days) was obtained and used as the main database. 15 × 15 km spatial resolution of the data is written in the image of Lambert conical shape. The cell density of 7101 cells is around. Finally, the matrix is composed of 7101 × 18183 was used as the main database. In order to investigate changes in zones where hot and cold temperatures, the statistical period equal to five times and divided into temperature zones in each period hot and cold identifying been examined and changes in the next period. It should be noted that in this study for the calculation of MATLAB and the Mapping software is used SURFER. First, to identify zones of hot and cold temperatures have used cluster analysis.
    In order to validate the hot and cold zones such as temperature indicators Davies-Bouldin index validation, Silhouette index and discriminant analysis were used.
    Results and DiscussionThe results of this study showed that:- Zones of cold temperatures on average 12.3 percent of the country's area, which is further along the Zagros Mountains, North West and small parts of the North East in the covers.
    - The extent of an area of cold temperature to the recent period, in addition to the reduction has been cold-zone average temperature has increased significantly. For example, an area of cold temperature in the decade 1341 to 1350 with an average temperature of 7/12 nearly 63/26 percent of the country is covered while the fifth period (1381 to 1390) is about the average temperature 7/13 ° C with an area of 13.6 percent.
    In addition to this it can be deduced that the role of greenhouse Persian Gulf zone heat in this region of the country has a great impact.
    - Warm temperature zone countries, following the recent period of global warming has increased.1 ° C increase.
    - Spatial distribution of hot and cold temperatures across the country most affected by local factors such as altitude and latitude. Meanwhile, more obvious is the height of the cold temperature zone so that cold zones of temperature and altitude has been more uneven matches.
    ConclusionThe aim of this study is to identify zones of warm and cold temperatures and changes during the period are different. For this purpose, the daily temperature data for 238 synoptic stations during the period 1341 to 1390 the country extracted Meteorological Organization. To identify changes in hot and cold temperatures zone period equal to five times (1350-1341, 1360-1351, 1370-1361, 1380-1371 and 1390-1381) and split hot and cold temperature zones in each period have been detected and changes in the next period examined. To identify the zone cluster analysis and multivariate statistical methods to validate the temperature of indicators such as hot and cold zones, Davies-Bouldin index validation (DBI), Silhouette index (SI) and discriminant analysis is used. The results of this study indicate that the temperature of the heat zones In the recent period, in addition to the spatial range to higher latitudes (towards the northern latitudes and almost 2.3 per cent) is drawn over the recent period has increased 3.1 degrees Celsius. This is while Iran to the cold temperature zones recent period In addition to the spaciousness of reducing the amount of temperature increase is tangible So that the average temperature of the cold zone in the first period (1341-1350) with a temperature 7/12 ° C range, which is 4/26 of the fifth period (1390-1381) the extent to 8/25 at 4 / 13 degrees Celsius, which represents an increase in temperature of 7.0 ° C cold zone. The results of the validation Davis-Bouldin index, Silhouette index and discriminant analysis showed that generally cold and heat zones of the top 98% in their respective groups, respectively.
    Keywords: clustering, Davies-Bouldin index validation (DBI, Silhouette index (SI), discriminant analysis, temperature
  • Masoud Sistani Badooei, Hossein Negaresh, Sammad Fotoohi Pages 163-182
    Introduction

    Flood risks are considered as the most important and hazardous natural risks of Iran, which haveoccurred more and more severely in recent years. The severity of this risk in the Gabrik drainage Basin is more due to geographic position, special climate, and geology conditions and basin factors while a numerous volume of floodwater flow leads to destruction of residential places, agricultural lands, as well as human and financial damages every year. The target region was one of the main drainage basins of south east shoreline of Iran placedin the East of Hormozgan province. This study aims to decrease human and financial damages inducing floodwater hazards in the available residential places of the basin using statistical analysis, field survey, and evaluation resulting to detecting and providing zoning plan of floodgate regions. In this study, different techniques are recruited in a new form to detect effective parameters of floodwater occurrence, meanwhile their layers are combined using Geographic Information System and a highly accurate plan is illustrated. The results of this zoning indicate the regions with high and very high risk include, in sum, 23.4 percent of area meaning that flooding state of wide zones of this basin is the result of temporal raining, low permeability, critical slope, and erodibility. Therefore, executing watershedplans and constructing dams are very necessary to decrease and control this risk and improve the region conditions. Study AreaOne of the main drainage basins of south eastern of Iran is theGabrik drainage basin including an area of about4404square kilometers, which is placed between between 58° 06' 45" to east longitude of 58° 47' 48" and 25° 46' 27" up to north width of 26° 47' 34".This basin is placed in south eastern of Hormozganprovince, inJassktownship regarding political divisions. The target basin originates under the basins of Bandar Abbas-Saddijdrainage, and its output stream flow to Oman Sea located70 Km east of Jask Township, which is in north ofBeshagard Mountains, south ofOman Sea,east ofSaddij drainage basin and westof Jegin drainage basin.

    Material and Methods

    The statistical analysis, field study, and assessment of remote sensing methods are used in this study. Different data are used to zone the Gabric drainage basin regarding floodwater hazards. Topography maps including maps in scale of 1:25000 covering all around of Iran, which were provided by IranianNational Cartographic Centre were used. The geological maps providedby Geological SurveyofIran and mining discoveries wereused to prepare geology map of the Gabric drainage basin in digits as well as evaluating available information.Its erodibility and permeability was measuredby ArcGIS 10 software package. The degree of erodibility and permeability was determined based on the geological instruction of counseling engineers in Iran. Satellite images of the ETM Imagery, Landsat 8 satellite in November 2014 wereused to analyze and evaluate the vegetation range of Gabric drainage basin. In order to measure the climatology of GabricBasin, the statistics available for the stations including climatology and Lir stations during 20 years and the close stations including Synoptic station of Jask, Minab with 30 years’ period, Totan climatology stations, Dahandar, Bikh, Dad Khodawell, Khomeini Shahr, Tidr and Kermestan with 20 years statistical period were used. For the field survey, the deposits of the studied region were detected and their height was measured by GPS. The floodwater hazard of the Gabric drainage basin waszoned using GIS. First, effective factors on creating flood water weredetected and selected; meanwhile, its layers wereclassified and prepared to provide this map by experts of soil in Hormouzgan Province. These layers are weighted based on their effectiveness. Then, the layers were weighted using AHP in Expert Choice Software Package and combined in GIS software leading to the final map. In addition, the potentiality offlooding of each basin in gabricwas determined based on Zonal Statistics and in order to prepare the layers, different methods such as statistical techniques, GS software for choosing the best torque, measurement of convergence and divergence, as well as other factors such as height by Simple Cokriging, and SAVI Index for examining the plant coverage of the basing with ENVI Software were used.

    Results and DiscussionIn

    orderto combine nineeffective criteriato prepare the map of zoning of floodwater hazards in Gabrik drainage basin, the raster layer of each one of these criteria wasdivided and weighted into different parts with different values as well as a 50-meter pixel size. Then the weight value of these criteriaand accumulative weighting order of Raster Calculatorwerecombined using Geographic Information System and GIS Software and the final map for flooding prone regions in Gabrik drainage basin wasprepared. The flooding statues of each sub-basin using Zonal Statistics Method wasevaluated.The obtained results show that the regions with very high risks include 8.4 percent, the regions with high risk include15 percent, the region with mean risk include34.7 percentof the basin area. The regions with low risks include32.8 percent and finally, the regions with very low risk include9.1 percent of the basin area. In this region, 10 sub-basins are in danger of very high risk, 17 sub-basins are in danger of high risk, 16 sub-basins are in danger of mean risk, foursub-basins are in danger of low risk, and sevensub-basins are in danger of very low risk of floodwater hazard. Therefore,in sum, the main and most important natural hazard in Gabrik drainage basin is the floodwater hazard, which occurs due to special climate, geologicaland physiographical conditions.

    Conclusion

    The objective of this study is detecting the reasons of flooding and zoning of floodwater risks in Gabrik drainage Basin, which is one of the main drainage Basins of Oman Sea shoreline placing in the east of Hormozganprovince. Wide range of studies were conducted to recognize natural conditions of this basin byevaluating and analyzing its alluvial terraces sediments using field study during January 2014indicating the effect of different factors such as climate, basin, and physical factors withrespect toincreasing severity of basin flooding (SistaniBadooei, Negaresh and Fotoohi, 2014). These factors resulted inspecial geographic conditions of east south of Iran, which led to the development of flood risk and changing it to the most important natural risk of the region due to existence of insatiable geological and erosionable structures, as well as severe rainfall. Based on the statistics reported by HormozganProvinceNatural Resources and Watershed Department in 2011, there are 94 villages in the Gabrik drainage Basin and their overall population is 5926. Theymainly inhabit near the main river and floodplain and earn money from agriculture and animal husbandry, especially in the outer part of the basin. Therefore, the pan of flood risk in this basin is prepared to detect the risky regions and decrease human and financial damages. The effective factors and criteria of flood occurrence including temperature, annual evaporation, vegetation of basin, slope of basin, ground permeability, erodibility, ability of geological structures, the distance of the main river, the field of floodplain, detecting available alluvial terrace sediments in the basin, use of lands and geomorphology plans are detected and classified regarding their effects withrespect toseverity and weakness of flood risks based on the results of distributed questionnaires by the personnel of Land Protection and Watershed of Hormozganprovince. Different data including topography plans with a scale of 1:25000, geological plans, satellite pictures, field capture, and the statistics of climatology stations, rain measurement,and synoptic are recruited to prepare each of above mentioned criteria, which are analyzed using techniques like ground statistics, SAVI Indicatorprocessed, prepared and combined using GIS System. Thus,the final plan of zoning of the flood risk in this field is prepared. What obviously can be indicated in this plan is the severe state of flooding, in such a way that around 8.4 percent of the area includes the regions with very high risk, 15 percent with high risk, 34.7 percent with moderate risk, 32.8 percent with low risk and only 9.1 percent with very low risk, which do not result in a proper conditions of life. Peopleneed water resources based on the regional statistics, most of available sub-basins in this basin have very high flood risk indicating severe conditions of flood risk. In sum, several different climatic, physiographical and basin changes have all changedGabrik Basin to one of the most severe flood-causing basins in Iran. Since all of the connecting ways to the basin is at the time of low level of water in the river, the flooding could hinder passing and bring about so many problems for the people living in the villages. Hence, public informing and training aboutfloods, informing the inhabitants of the basin villages about hazardous regions, preventing people from constructing houses near to the river,and executing watershedplans and constructing dams are required to improve current state and decreasehuman and financial damage inducing of flood risk.

     
    Keywords: Gabric drainage basin, Floodhazards, Zoning, Hormozgan, Geostatistics, GIS
  • Zeinab Teimoori Yansari, Seyed Reza Hosseinzadeh, Ataollah Kavian, Hamid Reza Pourghasemi Pages 183-204
    IntroductionLandslide is a common geomorphic hazard with considerable economic and ecological consequences. Globally, landslides cause billions of dollars in damage and thousands of deaths and injuries each year. Developing countries mostly suffer from landslide up to 0.5% of their gross national product (GNP) per year. It is hence necessary to study landslide by susceptibility mapping, hazard mapping, and systematic risk assessment tools. These measures enable us to mitigate or to control the damages caused by landslides. Identification and mapping of landslides prone areas are two major steps in the elevation of environmental risks and play a positive role in watershed management. The main purpose of this paper is to determine landslide-prone areas in the Chahardangeh watershed using the Shannon entropy index.
    Study AreaThe study area is located in the Southern part of Sari city, between 36°07 ′31″ to 36° 26′31″N, and 3° 11′01″ to 53° 58′57″E, enclosing an area of 1210.80 km2. The mean annual precipitation is approximately 464.62 mm. The Chahardangeh watershed is mainly covered with Paleozoic and the Holocene formations.
    Material and MethodsLandslide susceptibility mapping in this research consists of four phases of data preparation, data correlation analysis, landslide susceptibility modeling, and model validation. The first step in landslide susceptibility analysis is to collect information about antecedent landslide incidents. For this purpose, the locations of landslides were identified on Google Earth images and during extensive field surveys. The model was trained using the randomly selected incidents on the landslide inventory map, from which 70% was used for modeling, and the remaining 30% was used for the model validation. The identification and selection of the relevant landslide conditioning factors are two necessary steps, to develop a reliable landslide susceptibility zonation map. The factors controlling instabilities considered in the present study are slope gradient, slope aspect, plan curvature, profile curvature, topographic wetness index (TWI), altitude (obtained from the DEM produced from the topographic map at the scale of 1:50,000), land use (provided by the Forest, Rangeland, and Watershed Management Organization), and NDVI (calculated from NDVI= (IR-R)/(IR) where IR is the infrared band and R is the red band). Lithology map was prepared from two geological maps of Kyasar and Polsefid at the scale of 1:100,000, in paper sheet format. These maps were digitized in ArcGIS and divided into 11 lithology groups. This information was even used to prepare the distance to faults and fault density maps. Maps of distance to streams, distance to roads, drainage density and road density were produced from the DEM.
    An important consideration in landslide susceptibility maps is the correlation between independent variables. Tolerance and the variance inflation factor (VIF) are two important indicators of multi-collinearity. The entropy index serves as a measure of the extent of the instability, disorder, imbalance, and uncertainty of a system.
    The entropy of a landslide refers to the extent that various factors influence its development. This index determines the weight of each parameter.
    The final landslide susceptibility map was developed based on the following equation in ArcGIS.
    Ls= ∑_(i=1)^n▒W_f *C_f
    Where C_f is the conditioning factors on landslide occurrence
    Verification is a fundamental step in the development of susceptibility maps and its verification. Among the 485 landslides identified, 340 (70%) locations were used for landslide susceptibility mapping, and the remaining 145 (30%) locations were used for model validation. In this study, the accuracy of the susceptibility maps was verified by the ROC curve. The range of values of the AUC by 0.5–1 was indicative of a good fit of the model.
    Results and DiscussionCorrelation among independent variables is a significant concern in landslide susceptibility mapping. According to the results, the smallest tolerance and the highest variance inflation factor were 0.387 and 2.58, respectively. Therefore, there was not any multicollinearity between the independent factors.
    We used the index of entropy (IoE) for landslide susceptibility mapping, This method allows the calculation of the weight for each input variable. The resultant weights obtained for each thematic map from IoE change in the following order: elevation (0.6)> slope gradient (0.52)> plan curvature (0.29)> landuse(0.215)> NDVI(0.199)> profile curvature (0.156)> TWI(0.155) > lithology(0.107)> distance to streams (0.106)> topographic position index (0.1). These factors exert the greatest influence over landslides occurrence in the study area. The susceptibility map, produced by IoE, was divided into four classes including low, moderate, high and very high (24.66, 26.39, 25.63 and 23.31). Approximately 51.05% of the area had high sensitivity to a landslide, which could be explained by the susceptibility of the geological formations to landslide occurrence in the central part of the Elburz Mountains. This part, which covers 65.32% of the total study area, contains conglomerates, sandstones with interbedded marl, sandstone, limestone, and shale intersected with marl. The indiscriminate exploitation of natural resources and the existence of numerous pathways are important factors in rendering this area sensitive to mass movements. Landslide susceptibility map validation using AUC obtained an index of entropy (IoE) of 0.766.
    ConclusionLandslide is one of the most dangerous natural disasters worldwide. In this research, 16 factors were evaluated by employing the Shannon Entropy Index. These factors included slope gradient, slope direction, elevation classes, plan and profile curvature, topographic position index, topography wetness index, lithology, distance to faults, fault density, land use, NDVI, distance to streams, drainage density, distance to roads and road density. These factors were then used to plot the landslide sensitivity map using the index of entropy (IoE). For this purpose, 70% of landslide locations were used for modeling and the remaining 30% for model validation. In total, 51.5% of the area was highly susceptible to landslide occurrence. Among the factors affecting landslide, elevation, slope gradient, plan curvature, land use, NDVI, profile curvature, topographic wetness index and lithology had the highest weights and impact. Additionally, model accuracy assessment using the ROC curve with a 76.6% area under the curve, indicated a suitable model performance in the study area. Therefore, the landslide sensitivity map can play a major role in planning and the management of the area to prevent and reduce the damages caused by this hazard.
    Keywords: Landslide zoning, Shannon entropy index, Receiver operating characteristics, Chahardangeh watershed