فهرست مطالب

نشریه تحلیل فضایی مخاطرات محیطی
سال هفتم شماره 2 (تابستان 1399)

  • تاریخ انتشار: 1399/09/16
  • تعداد عناوین: 12
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  • باقر کرد، امین راحتی، پیمان محمودی*، پرویز خسروی، حریر بیدار صفحات 1-20

    یکی از مشکلات اساسی در بحث مدیریت خشکسالی، تخصیص بودجه جهت کمک به آسیب دیدگان از این پدیده اقلیمی است که گاها مشاهده شده است که هیچ سازوکار مشخصی برای آن تعریف نشده است و بعضی اوقات نیز مشاهده شده است که این تخصیص ها بر اساس علایق منطقه ای و سیاسی بوده است و آسیب دیدگان اصلی از خشکسالی ها از این کمک ها بی بهره بوده اند، لذا این تحقیق به دنبال طراحی یک الگوریتم فراابتکارانه هوشمند جهت مدیریت بودجه خشکسالی در استان سیستان و بلوچستان می باشد. در این مطالعه از شاخص هایی همچون جمعیت، برخورداری از آب شرب شهری و روستایی، آسیب پذیری منابع آب، میزان سطح زیر کشت، تعداد بهره برداران بخش کشاورزی، مصرف سالیانه آب کشاورزی و نزولات جوی استفاده شده است. مقادیری عددی مربوط به هر کدام از این شاخص ها به تفکیک هر شهرستان جمع آوری شدند. اما با توجه به اینکه این شاخص ها در هر شهرستان از اهمیت یکسانی برخوردار نیستند و ممکن است برخی از آنها در یک شهرستان اهمیت بیشتری و در شهرستان دیگری اهمیت کمتری داشته باشند، از تکنیک تحلیل سلسله مراتبی (AHP) با استفاده از روش مقایسه زوجی برای تعیین اهمیت نسبی این شاخص ها کمک گرفته شد. برای تعیین طبقات مختلف خشکسالی نیز از شاخص استاندارد شده بارش SPI  استفاده شد. بعد از تعیین مقادیر عددی طبقات مختلف خشکسالی های استان، از الگوریتم کلونی مورچگان برای اولویت بندی شهرستان ها جهت مدیریت بهینه بودجه خشکسالی استفاده شد که نتایج این الگوریتم در قالب نقشه های اولویت بندی مدیریت بودجه خشکسالی استان ارایه شدند.  با توجه به معیارهای انتخاب شده و روش کار پیشنهادی به نظر می رسد که ترکیب تکنیک تحلیل سلسله مراتبی (AHP) و الگوریتم کلونی مورچگان قادر به تدوین سیستمی هوشمند حهت تعیین اولویت شهرستان های استان سیستان و بلوچستان در زمان وقوع خشکسالی ها برای اختصاص بودجه بهینه در خصوص کاهش اثرات مخرب خشکسالی ها باشند. بر اساس نقشه های اولویت بندی تخصیص بودجه بهینه خشکسالی بین شهرستان های استان سیستان و بلوچستان به راحتی مشاهده می شود که نتایج با واقعیت های موجود در استان تقریبا هماهنگی خوبی نشان می دهد.

    کلیدواژگان: خشکسالی، استان سیستان و بلوچستان، الگوریتم کلونی مورچگان، تحلیل سلسله مراتبی، بودجه، مدیریت
  • موسی کمانرودی کجوری*، امیر صفاری، محمد سلیمانی، مریم نعمتی ثانی صفحات 21-32

    ایران به دلیل اقلیم غالبا خشک و نیمه خشک، بارندگی های کم و فصلی و توپوگرافی متنوع، از رود-دره ها یا رودخانه های فصلی فراوانی برخوردار است. این رود-دره ها نقش اساسی در شکل گیری، تکوین و پایداری سکونتگاه های انسانی دارند و خدمات اکولوژیک متنوعی ارایه می نمایند. زیبا یی بصری، ذخیره فضای سبز، تامین آب، کاهش و ایجاد اختلاف دما، فشار و جریان محلی هوا (باد) و تهویه طبیعی از جمله کارکردها و خدمات اصلی این واحدهای طبیعی-اکولوژیک می باشند. شهر تهران از 7 رود-دره دارآباد، گلابدره، دربند، ولنجک، درکه، فرحزاد و کن برخوردار است. نقش اکولوژیک  این رود-دره ها در چنددهه اخیر به دلیل رویکرد و مداخله های عمرانی غیر اکولوژیک محور مدیریت شهری و شهروندان به شدت کاهش یافته است. این مداخله ها این رود-دره ها را به یکی از مهم ترین عرصه های خطر بروز سیل و حرکات دامنه ای تبدیل کرده است. رود-دره کن، مهم ترین این رود-دره ها به جهت وسعت حوضه آبریز و مدت زمان و میزان دبی آب دایمی می باشد. بخشی از این رود-دره توسط شهرداری به بوستان (جوانمردان) تبدیل شده است. هدف این پژوهش این بوده که عوامل و معیارهای مدیریت اکولوژیک محور این رود-دره را برای مداخله ها و ساماندهی پایدار آن تدوین و ارایه نماید. اطلاعات مورد نیاز این پژوهش به دو روش کتابخانه ای و پیمایشی جمع آوری شده است. به منظور ارایه این عوامل و معیارها، از روش ارزیابی چند معیاره مبتنی بر فرایند تحلیل شبکه ای استفاده شده است. نتیجه حاصل از این ارزیابی نشان می دهد که عامل مدیریتی، بیشترین درجه اهمیت و وزن را نسبت به عوامل دیگر در این خصوص دارد.

    کلیدواژگان: اکوسیستم، مدیریت اکولوژیک محور، فرایند تحلیل شبکه ای، رود-دره کن
  • بهزاد رایگانی*، فرگل گودرزی، احمد طالبی، محمد طلائیان عراقی، هادی هاشمی صفحات 33-48

    در این تحقیق ارزیابی تاثیرات احتمالی تغییر کاربری اراضی بر کیفیت آب تالاب شادگان به کمک داده های دورسنجی به عنوان هدف اصلی قرار داده شده است. هدف از انجام این تحقیق بررسی و مقایسه تغییرات کاربری در سال 2000 و 2015 با استفاده از تصاویر ماهواره لندست (با سنجنده ETM,OLI) از محدوده مطالعاتی و پردازش آنها در محیط نرم افزار ERDAS به کمک روش طبقه بندی نظارت نشده در طی یک دوره 15 ساله بررسی گردیده است. برای تعیین علت تغییرات رخ داده در تالاب، کیفیت آب تالاب به کمک مدلسازی های تعیین شده مورد بررسی قرار گرفت. پوشش گیاهی در تالاب به سرعت رو به افزایش بوده که نشان از آلودگی آب، افزایش پدیده تغذیه گرایی و از بین رفتن زود به هنگام این تالاب بین المللی دارد. توسعه زمین های کشاورزی در اطراف تالاب شادگان از سال 2000 تا 2015، باعث افزایش روزافزون آلودگی در منطقه شده است. طبق اسناد موجود، پساب های حاصل از کشاورزی که حاوی مقادیر زیادی علف کش و آفت کش است موجب بالا رفتن رشد جلبک در تالاب شده که بدنبال آن افزایش دما و در نهایت مرگ تالاب و آبزیان رو به همراه داشته است. بنابراین پس از انتخاب، تصاویر و تعیین آنها در 5 کلاس، نقشه های تغییر کاربری تالاب در طی یک بازه 15 ساله بدست آمد. از منابع مختلفی جهت بررسی بهترین مدل رگرسیونی برای تعیین تغییرات کیفیت آب استفاده شد. در ادامه، تصاویر در مدل ها قرار گرفتند و میانگین و انحراف معیار آنها بدست آمد. نتایح تحقیقات نشان داد که، سنجنده Landsat، کیفیت آب را به خوبی نشان می دهد و می توان از آن در جهت تعیین تغییرات استفاده کرد. توسعه زمین های کشاورزی باعث افزایش پدیده یوتریفیکاسیون در تالاب و در نهایت باعث افت کیفیت شاخص های آب می شود. در این راستا جلوگیری از ورود انواع آلودگی ها و تضمین کیفیت آب تالاب شادگان از طریق کنترل و نظارت های مکرر، پیشنهاد می شود.

    کلیدواژگان: ماهواره landsat، تالاب، آلودگی، دورسنجی، شادگان، کاربری اراضی
  • زهرا شریفی نیا* صفحات 49-66

    پژوهش حاضر از لحاظ هدف کاربردی، و از لحاظ روش، توصیفی - تحلیلی است. گردآوری داده ها با استفاده از روش اسنادی و میدانی (مشاهده و پرسشنامه) جمع آوری شده است، جامع آماری این نوع تحقیق براساس سرشماری آمار1395؛ 6947 خانوار در24 روستا؛ با خطای 07/0، 191 پرسشنامه به عنوان حجم نمونه محاسبه و براساس رابطه تسهیم نسبت تعداد نمونه های هر روستا به 233 نمونه به صورت تصادفی بین خانوارها توزیع و پخش گردید. برای تجزیه و تحلیل داده ها از اطلاعات از روش های آماری توصیفی (میانگین) و استنباطی (t تک نمونه، فریدمن، تحلیل خوشه ای) و مدل های واس پاس، آراس و ویکور،  بهره گرفته شد. نتایج نشان می دهد که تاب آوری مناطق روستایی در برابر خشکسالی در سطح پایینی است. یافته های مدل های ویکور، اراس و مدل واس پاس نشان داد که روستاهای ولاشد؛ تازه آباد بستان خیل و دوقایلو رتبه های اول و تاب آوری بالا و روستاهای جمان، پلاژارتش و بهزاد کلا در رتبه های پایین و تاب آوری پایین قرار دارند.

    کلیدواژگان: مناطق روستایی، تاب آوری، خشکسالی، دهستان قره طغان
  • جواد سدیدی*، زهرا جودکی، هانی رضائیان صفحات 67-80

    با توجه به وسیعتر و پیچیده تر شدن فضای بسته داخل ساختمان ها مانند فرودگاه ها، مراکز خرید و بیمارستان ها نیاز به سیستم های ناوبری در فضای بسته (Indoor) جهت راهنمایی کاربر مخصوصا در مواقع بحران مانند زلزله و آتش سوزی احساس میشود. هدف اصلی این پژوهش طراحی و پیاده سازی سیستم تحت وب ناوبری در فضای سه بعدی داخل ساختمان است. این سیستم بطور اتوماتیک مدل داده CityGML را پردازش کرده، و اطلاعات مفهومی، توپولوژی و ژیومتری مانند، پلان طبقات، کاربری فضاهای داخلی و نحوه اتصال این فضا ها را از آن استخراج و سپس یک گراف مسیریابی از اطلاعات استخراج شده تولید می کند. پردازش مدل داده CityGML و آنالیز گراف و مسیریابی در سمت سرور و با استفاده از زبان برنامه نویسی Python انجام شده، و رابط کاربری نیز با استفاده از زبان های توسعه وب مانند HTML، JavaScript، JQuery و AJAX توسعه یافته است. از ویژگی های این وب اپلیکیشن، ارایه مسیر و مدل سه بعدی ساختمان در یک محیط سه بعدی است که با استفاده از کره مجازی Cesium ایجادشده و علاوه بر آن به همراه مسیر محاسبه شده یک راهنمای توصیفی نیز در اختیار کاربر قرار می گیردکه باعث درک بهتر از مسیر شده است. انجام اتوماتیک پردازش مدل داده CityGML و تولید گراف و مسیریابی، توسط موتور نرم افزاری توسعه داده شده در این پژوهش باعث شده تا نیازی به استفاده از هرگونه نرم افزار جانبی برای اینگونه محاسبات نباشد. امکان اجرای این نرم افزار روی هر وسیله ای که به شبکه اینترنت متصل و مجهز به یک مرورگر رایج وب باشد، وجود دارد

    کلیدواژگان: مسیر یابی سه بعد ی، وب اپلی کیشن، فضاهای داخلی، مخاطرات محیطی
  • علی عشقی چهاربرج*، حسین نظم فر، عطا غفاری صفحات 81-101

    در چند دهه اخیر زلزله به عنوان یکی از مخرب ترین مخاطره محیطی خسارت های بسیاری را به اموال و دارایی ها در نواحی شهری و اطراف آن وارد نموده است، با توجه به اینکه زلزله به عنوان نیروی محرک بیرونی ثابت است برای کاهش آسیب پذیری به افزایش تاب آوری نیاز است. بر این اساس پژوهش حاضر با هدف ارزیابی وضعیت تاب آوری نواحی ده گانه منطقه یک شهرداری تهران در برابر زلزله صورت گرفته است. روش این پژوهش از نوع توصیفی- تحلیلی با هدف کاربردی است. قلمرو پژوهش نواحی ده گانه منطقه یک شهرداری تهران می باشد. برای تعیین اهمیت نسبی هر یک از مولفه ها از فرآیند تحلیل شبکه ای (ANP) استفاده شده است. برای رتبه بندی وضعیت تاب آوری نواحی ده گانه منطقه یک شهرداری تهران در برابر زلزله از روش های تصمیم گیری چند معیاره شامل تاپسیس، ویکور، HAW و SAW استفاده شد، سپس برای رسیدن به یک نتیجه واحد از این تحلیل ها، از مدل تلفیقی کاندرست بهره گرفته شده است. نتایج حاصل از پژوهش نشان می دهد که نواحی 2، 4، 5 و 3 با کسب بالاترین رتبه از تاب آوری زیادی، نواحی 7، 8 و 1 از تاب آوری متوسط، ناحیه 10 و 6 از تاب آوری کم و ناحیه 9 از تاب آوری خیلی کم در برابر زلزله برخوردار می باشد که می بایست در برنامه ریزی های آتی در اولویت برنامه ریزی قرار گیرد.

    کلیدواژگان: تاب آوری، تاپسیس، ویکور، HAW، SAW، کاندرست
  • ثریا یعقوبی، کامران کریمی*، مرزبان فرامرزی صفحات 103-120

    در حال حاضر بیابان زایی به عنوان یک معضل گریبان گیر بسیاری از کشورهای جهان از جمله کشورهای در حال توسعه است. این معضل مشتمل بر فرآیندهایی است که هم زاییده عوامل طبیعی بوده و هم به عملکرد نادرست انسان برمی گردد. هدف از این پژوهش مقایسه بیابان زایی و خشکسالی دشت عباس و دشت دهلران به ترتیب با مساحت 34104 و54252 هکتار می باشد.در این مطالعه با استفاده از مدل ایرانی IMDPA شدت بیابان زایی دشت عباس و دشت دهلران در دوره زمانی 88-1384و 93-1389 مورد ارزیابی قرار گرفت. به همین منظور معیار اقلیم به عنوان موثرترین معیار ارزیابی بیابان زایی در نظر گرفته شد. برای معیار اقلیم سه شاخص بارش سالانه، شاخص خشکسالی SPI و استمرا خشکسالی در نظر گرفته شد. بعد از آماده سازی داده ها با استفاده از جدول امتیازدهی مدل IMDPA هریک از شاخص ها بصورت لایه های اطلاعاتی وارد نرم افزار Arc GIS 9.3 شد. در نهایت با استفاده از میانگین هندسی نقشه های تهیه شده دو دوره زمانی  با هم ادغام شده و با قرار دادن لایه های امتیاز دهی شده سه شاخص مذکور نقشه نهایی مدل IMDPA از اقلیم دشت عباس و دشت دهلران تهیه گردید. نتایج تحقیق نشان داد که شاخص SPI به عنوان موثرترین شاخص،در دشت عباس در دو دوره به ترتیب با میانگین وزنی 04/3 و 5/3 در طبقه شدید با زیر کلاس 2 و 3 قرار دارد. در مقابل در دشت دهلران نیز شاخص SPI در دوره اول و دوم با میانگین وزنی 93/1 و 25/2 در طبقات متوسط زیر کلاس 1 و 2 و 3 و شدید زیر کلاس 1 قرار گرفته است. می توان نتیجه گرفت که شدت بیابان زایی در دشت عباس در مقایسه با دشت دهلران از نظر اقلیم در شرایط نامطلوبیقرار دارد. بطوری که وقوع بیابان زایی با شدت بیشتر در دهه های آتی  دور از انتظار نخواهد بود

    کلیدواژگان: بیابان زایی، IMDPA، اقلیم، دشت عباس، دشت دهلران
  • نیما سهراب نیا*، بهلول علیجانی، مهری اکبری صفحات 121-136

    در این تحقیق به مطالعه چگونگی اثرات تغییرات اقلیمی بر جریان رودخانه های حوضه های منتخب استان گیلان، یکی از استان های شمالی کشور ایران برای دوره ی سالهای 2020 تا 2050 و تحت سه سناریوی اقلیمی RCP2.6، RCP4.5، RCP8.5 پرداخته شد. برای این منظور از داده های بارش و دمای 45 ایستگاه داده های اقلیمی و 20 ایستگاه آب سنجی در دوره ی 1983 تا 2013 ستفاده شد. محاسبه متوسط بارش و دما در سطح حوضه ها از طریق ترسیم خطوط هم باران و هم دما با روش کریجینگ انجام گرفت. جهت تعیین معناداری روند داده های مورد مطالعه و مقدار شیب آنها به ترتیب از آزمون های من-کندال و شیب سنس کمک گرفته شد. نتایج نشان داد، دما طی دوره ی مورد مطالعه در همه ی حوضه های آبریز روند افزایشی داشته و این روند در اکثر آنها معنادار بوده است اما برای بارش ها روند معناداری مشاهده نشد. همچنین آبدهی در اکثر حوضه ها کاهشی بوده و در حوضه های شفارود، ناورود و چافرود این روند معنادار است. از سوی دیگر برای دوره های آینده، بارش ها در هیچ یک از سناریوهای اقلیمی روند معناداری ندارند اما دما در به غیر از سناریوی RCP2.6 در سناریوهای دیگر دارای روند افزایشی است. آب دهی رودخانه ها نیز در سناریوی RCP2.6 در هیچ یک از حوضه ها روند معناداری ندارد اما در سناریوی RCP4.5  در دو حوضه ی آبریز شفارود و گشت رودخان روند کاهشی معنادار در سطح اطمینان 95 درصد دیده می شود که این روند در سناریوی RCP8.5 در حوضه های چافرود و شفارود در سطح اطمینان 99 درصد نیز معنادار می باشد.

    کلیدواژگان: سناریوهای اقلیمی، آب دهی رودخانه ها، من-کندال، شیب سنس، استان گیلان
  • کوهزاد رئیس پور*، یونس خسروی صفحات 137-152

    با توجه به اهمیت حیاتی هوا و سیر صعودی افزایش عوامل آلوده کننده ی آن، ضرورت مطالعه ی عوامل آلاینده ی آن به منظور آگاهی از وضعیت موجود امری ضروری به نظر می رسد.  پدیده ی آلودگی هوا یکی از مهمترین معضلات بخشهای زیادی از کشور ایران می باشد که به دلایل متعددی روز به روز بر میزان آن افزوده شده است. مونوکسید کربن یکی از خطرناکترین آلاینده های معیار هوا می باشد که با توجه به اهمیت مطالعه ی آن، تکنیکها و روش های متعددی جهت پایش آن در اتمسفر کره زمین به کار گرفته شده است. در این مطالعه نیز از داده های مونوکسید کربن سنجنده ی AIRS Aqua/ که امکان بررسی میزان و روند تغییرات گاز مونوکسید کربن را در اتمسفر تمام جهان فراهم نموده استفاده گردید. داده های مربوطه با فرمت NetCDF طی دوره ی آماری (2018 - 2003) از وبگاه استخراج و با استفاده از نرم افزارهای ArcGIS  و Grads بارزسازی و تحلیل شده است. نتایج حاصله بیانگر کاهش میزان مونوکسید کربن در طول سریهای زمانی ماهانه  و سالانه ی بوده است. در این میان تفاوتهای ماهانه و فصلی بسیار چشمگیر بوده به طوری که به لحاظ ماهانه، بیشترین میزان مونوکسید کربن در ماه های ژانوبه، فوریه و مارس و کمترین میزان آن در ماه های آگوست، سپتامبر و اکتبر اتفاق افتاده است. در میان فصول، بیشترین و کمترین میزان مونوکسید کربن به ترتیب در فصول زمستان و تابستان مشاهده گردید. به لحاظ مکانی نیز، بیشترین میزان مونوکسید کربن سطحی با میانگین  ppb150 بر فراز شهر تهران و ناحیه ساحلی دریای خزر و کمترین میزان آن با میانگین ppb 115 بر روی ارتفاعات زاگرس بارزسازی گردید.

    کلیدواژگان: آلودگی هوا، مونوکسید کربن، AIRS، سنجش از دور، ایران
  • ایرج قاسمی، فاطمه رزاقی بورخانی*، محمدعلی محمدی قره قانی، رسول لوایی آدریانی صفحات 153-168

    سالانه تعدادی از سکونتگاه های روستایی تحت تاثیر مخاطرات طبیعی و یا عوامل انسانی دستخوش تغییر می شوند؛ به طوری که ادامه حیات در این سکونتگاه ها مخاطره آمیز بوده و حتی در برخی موارد ناممکن است. بدین ترتیب برنامه های جابجایی در قالب ترک مکان اولیه و ایجاد سکونتگاه های جدید در مکان دیگری مورد توجه برنامه ریزان و مدیران قرار می گیرد. این برنامه ها غالبا بدون پیامد نبوده و ابعاد مختلف زندگی ساکنین را تحت تاثیر قرار می دهند. شناسایی این پیامدها می تواند تجارب و شواهد کافی برای مدیریت سایر پروژه های جابجایی فراهم نماید. بر این اساس، مطالعه حاضر با تمرکز بر جابجایی سکونتگاهی در روستای بلوچ آباد درصدد است تا با کشف بسترهای جابجایی و تبیین ادراک ساکنین از علل جابجایی، پیامدهای ناشی از آن را شناسایی نماید. این مطالعه به شیوه قوم نگاری هدایت شد و برای جمع آوری داده ها از تکنیک های مصاحبه عمیق، مشاهده غیرمشارکتی و گروه کانونی استفاده گردید. مشارکت کنندگان شامل ساکنین روستای بلوچ آباد بودند که به صورت هدفمند انتخاب شدند. نتایج نشان داد که پیامدهای جابجایی در ابعاد فیزیکی کالبدی، اجتماعی و اقتصادی رخ داده و این پیامدها از یکدیگر مستقل نیستند. پیامدهای اقتصادی و اجتماعی ریشه در ساختارهای فیزیکی کالبدی مساکن دارند و نیز پیامدهای اجتماعی علاوه بر آنکه از جنبه های فیزیکی کالبدی نشات می گیرند، ریشه در پیامدهای اقتصادی دارند. به طور کلی، بر مبنای نتایج می توان استنباط نمود که ساختارهای فیزیکی کالبدی آغازی برای رخداد سایر پیامدهای جابجایی به شمار می روند.

    کلیدواژگان: جابجایی سکونتگاهی، روستای بلوچ آباد، مخاطرات طبیعی، بسترها و پیامدهای جابجایی
  • علی اکبر شمسی پور*، ایوب جعفری، حسام بستانچی صفحات 169-185

    رخداد کولاک برف یکی از مخاطرات اقلیمی است که از ترکیب سایر عوامل اقلیمی مانند دما (دمای زیر صفر)، برف و باد (سرعت 15 متر بر ثانیه) رخ می دهد. در این تحقیق شرایط رخداد کولاک برف در شمال غرب ایران با روش های آماری و همدیدی انجام می شود. با تحلیل همه کدهای هواشناسی کولاک (36، 37، 38 و 39) در دوره آماری 1987-2016 برای 11 ایستگاه همدید منطقه مورد مطالعه، کدهای با کولاک شدید برف (37،39) انتخاب گردید. سپس با استفاده از داده های ارتفاع ژیوپتانسیل، باد و دمای ترازهای 500 و 850 هکتوپاسکال اخذ شده از پایگاه داده های باز تحلیل جوی  NCEPNCAR، الگوهای همدیدی رخداد کولاک واکاوی گردید. تحلیل های آماری در مورد ارتباط  اثر عوامل  جغرافیایی بر کولاک شدید برف نشان داد که عامل ارتفاع بیشترین تاثیر را در شدت، افزایش و تفاوت های مکانی رخداد این پدیده دارد. بررسی الگوهای همدید رخداد پدیده کولاک نشان داد که 5 الگوی اصلی در ایجاد آن در منطقه نقش دارد. الگوهای همدیدی ایجاد کننده شامل تشکیل یک مرکز کم ارتفاع بریده، عبور فرودی بلند از ایران، شکل گیری ناوه ی نسبتا عمیق و کشیده شده شرق مدیترانه، سامانه بندالی از نوع رکس و تشکیل سامانه های بندالی امگایی است. در بین الگوهای به دست آمده، الگوهایی که به صورت بندالی بودند، مهم ترین نقش را در ماندگاری و انتقال جریانات توام با سرما داشته و سایر الگوها علیرغم فراوانی که داشته اند به صورت دوره ای، از شدت و ضعف برخودار بودند.

    کلیدواژگان: کولاک برف، شمال غرب، سرعت باد، دمای زیر صفر، الگوهای همدید
  • حسن لشکری*، ندا اسفندیاری صفحات 187-206

    رودخانه های جوی ساختارهایی طولانی- باریک و متمرکز از شار بخارآب هستند که با بارش های فرین و سیلاب ها ارتباط بسیار نزدیکی دارند و مناطق خشک و نیمه خشک نسبت به این پدیده در آسیب پذیری بیشتری قرار دارند به همین جهت این مطالعه به شناسایی و معرفی بالاترین بارش های رخ داده به هنگام حضور رودخانه های جوی از نوامبر تا آوریل (2007-2018) پرداخت تا ضمن نشان دادن اهمیت این پدیده در ایجاد بارش های ابرسنگین و معرفی مناطق متاثر از آن عوامل همدید موثر بر آن ها را تحلیل کند. به منظور شناسایی رودخانه های جوی از داده های انتگرال قایم شار بخارآب استفاده شد و آستانه هایی مستند بر روی آن ها اعمال گردید. تاریخ رخداد هر رودخانه جوی با بارش روزانه آن ها موردبررسی قرار گرفت و ده مورد از بالاترین رخدادهای بارش ایستگاهی (معادل صدک 95 ام از حداکثر بارش ها) مرتبط با رودخانه های جوی معرفی و تحلیل گردید. نتایج نشان داد دریاهای گرم جنوبی به طور مستقیم و غیرمستقیم منشا عمده رودخانه های جوی مرتبط با بارش های ابرسنگین بوده است. منشا اکثر این رودخانه های جوی در زمان اوج رخداد دریاهای سرخ، خلیج عدن و منطقه شاخ آفریقا می باشد. ازلحاظ همدیدی منشا 7 مورد از رودخانه های جوی از کم فشار سودانی و در سه مورد باقیمانده از سامانه های ادغامی بوده است. دینامیک غالب در وردسپهر بالایی برای تکوین و قوام رودخانه جوی جت جنب حاره ای بوده است. در سامانه های سودانی ساختار غالب جت تمایل نصف النهاری و در سامانه های ادغامی گرایش مداری حاکمیت داشته است. به دلیل حاکمیت یک جریان بالاسوی قوی در هم جواری بالاترین شار رطوبتی جریانات همرفتی شدید سبب بارش های ابرسنگین گردیده است و ایستگاه دارای بالاترین بارش در منطقه شرق و شمال غربی میدان امگای منفی یا جریانات بالاسو قرار داشته است.

    کلیدواژگان: رودخانه های جوی، بارش ابرسنگین، تحلیل همدید، شار قائم بخارآب، ایران
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  • Baqer Kord, Amin Rahati, Peyman Mahmoudi*, Parviz Khosravi, Harir Bidar Pages 1-20

    Drought is one of the most significant natural hazards which affects various aspects of human life with its gradual, slow and creeping occurrence. As a disastrous climate phenomenon, it directly impacts on human communities through making changes in access to water resources, and imposes enormous economic, social and environmental costs on various communities. One of the strategies governments always use to compensate the damages that droughts impose on various economic, social and environmental sectors is to include special financial loans in the form of grants, special development credits, special structural projects, and so on. Therefore, in this regard, a lot of financial aids have been allocated by the government for it. But, sometimes, it is observed that the allocation and distribution of drought credits among different cities of the province have been more influenced by political, ethnic, and religious interests rather than by the severity of the drought and its detrimental effects on various economic, agricultural, and social sectors. Therefore, in this study, it has been tried to present a method based on an optimization model in order to take a step in optimizing the management of drought budget based on realities in Sistan and Baluchestan province in south-east of Iran. In this study, the indicators proposed by the Cabinet of Ministers of the Islamic Republic of Iran for reducing the effects of drought were applied to manage the optimal distribution of drought budgets among the cities of Sistan and Baluchestan province in southeast of  Iran. These indicators were population, having urban and rural drinking water, vulnerability of water resources, surface area under cultivation, number of users of agricultural sector, annual consumption of agricultural water, and rainfall. Using the figures given in the 2011 statistical yearbook, numerical values ​​for each of these indices were obtained. But given that these indices are not of equal importance in each city and some may be more important in one city and less important in another, the Analytical Hierarchy Process (AHP) technique using paired comparison method was applied to determine the relative importance of these indices in Sistan and Baluchestan province. Using this technique, a relative weight was determined for each of these indicators and for each city. In addition to determining the weight of these indices, it was needed to convert droughts in the province to numerical values. In this study, to analyze droughts in Sistan and Baluchestan province, Standardized Precipitation Index (SPI), which is one of the proposed indicators of World Meteorological Organization (WMO) has been used for a period of 30 years (1984-2014) and for 6 synoptic stations. The results of drought analysis in Sistan and Baluchestan province in an annual scale showed that the frequency distribution of different drought levels in Sistan and Baluchestan province has not been uniform, with the most droughts occurring in this 30 year period in northern part of the province (Zabol and Zahedan) including 14 and 13 repeated cases; respectively, with the lowest in central part of Baluchistan (Khash and Saravan) including 11 repeated cases. But, what should be noted after the frequency of droughts is the persistence and durability of droughts. As a result, weak but long-lasting droughts can be much more damaging than severe but short-lived droughts. Sistan and Baluchestan province has been under drought with varying degrees of severity from the water year of 1998-1999 to the water year of 2005-2006. But in the meantime, the north of Sistan and Baluchestan province (Zabol station) has a condition which is very different from other parts of the province. The north of Sistan and Baluchistan province has been experiencing severe droughts for 14 years from the year 1999-2000 to 2012-2013 with the exception of the year 2004-2005. It has been the long-term drought persistence in the province that has caused many environmental, economic and social problems, such as the drying up of Lake Hamoun and the water reduction in the Hirmand River in the north of the province, and severe reduction of groundwater resources in central Baluchistan. Therefore, given that Sistan and Baluchestan province has experienced 7 years of continuous drought between the two water years of 1998-1999 to 2009-2010, these seven years were chosen as examples, and the ant colony algorithm was implemented on them. Based on the selected criteria and the proposed method, it seems that the combination of Analytic hierarchy process (AHP) technique and Ant colony algorithm can formulate an intelligent system to determine the priority of the cities in Sistan and Baluchestan province during droughts for allocating the optimal budget and reducing the harmful effects of droughts. Based on the prioritization maps of optimal drought budget allocation among the cities in Sistan and Baluchestan province, an almost good agreement can be observed between the results and the realities existing in the province.

    Keywords: Sistan, Baluchestan, ant colony algorithm, Analytical Hierarchy Process, budget, Management
  • Mousa Kamanroudi Kojuri*, Amir Saffari, Mohammad Solimani, Maryam Nemati Sani Pages 21-32

    Iran has seasonal rivers because of dry climate, low rainfall and different topography. These river- valleys have main role in forming, genesis, and sustainability of human settlements and provide different ecological services. The main services include beauty, store of green spaces, water supply, reduce and create temperature differences, local air flow and natural ventilation which are part of the functions. Tehran is roughly the same area as 730 square kilometers and its population is 8.7 million people. It is located in51° and 17´ to 51° and 33´ east longitude and 35° and 36´ to 35° and 44´ north latitude. The height of this city is 900 to 1800 meters. The north and north east of this city are located in peculiarity range of the southern part of the middle Alborz. This city includes 7 river valleys to the names Darabad, Golabdareh, Darband, Velenjak, Darakeh, Farahzad and Kan. The ecological role of these river valleys is reduced because of non- ecological axis developmental interventions by urban management and citizens. These interventions have changed river valleys to high risk space of skirt movements and flood. Kan is the most important river valley because of the breadth of the basin and permanent water discharge rate. The part of this river valley has changed to park (Javanmardan) by municipality. The purpose of this research is that to provide factors and criteria of ecosystem based management to organize this river valley. ANP has been used in this research. To use this method for analyzing   factors and criteria of ecosystem based management to organize this river valley, firstly, these factors have been identified by library studies and scrolling. These factors include 4 criteria (natural: 15 sub criteria, social: 3, management:  6, economic: 2). the books, journals, reports, maps, aerial photos, satellite images and internet sites have been studied in library studies. In site studies, some information from library studies have been edited. After that, the findings of these two methods in form of questionnaire called factors and criteria of ecosystem based management to organize Kan River valley, was in charge academics and professionals. They were elected among pundits of urban management science, urban planning, geography and environment in Tehran. At first the number of them was 30 people came to agreement in two process about 4 factors and 18 criteria and determined importance and priority by Delphy method. Findings in Delphy method were analyzed through ANP and SUPER DECISIONS. In this process, firstly, a conceptual model and relation inter and intra clusters and nodes determined. These relations in this process are very important because paired comparison depends on this process. Assumption of equality of effects and similar relations in these factors is illogical because there are the grading of effects and relations in this research. Second, the factors have been compared to each other to create a super matrix based on paired comparison. Generally, in this process decision makers compare two different factors to each other and paired comparisons have grading of between1to9. In double- sided valuation, each factor is used to show initial inverse comparison. Inconsistent rate in paired comparison must be less than 0.1 like AHP. Third initial super matrix is created. It is the weights created from paired comparison and identified the importance of each factor in each cluster. Forth, the weighted super matrix was created. The weights of clusters was calculated in this process to identify the weight of final super matrix. Fifth, limited super matrix was created. The weighted super matrix reached for infinity band each row convergenced to a number and that number was the weight of factor. By this way limited super matrix was reached. Based on ANP and table 1, management: 46%, natural – ecological: 26% and economic and social factors: 14% are important respectively in ecosystem based management to organize Kan River valley. Based on reached results, inconsistent rate is 0.003 and it shows that the weight is valid and review is not necessary. Among sub criteria in management factor, organizational pattern: 32%, method of management: 23% and policies: 21% are the most important respectively in ecosystem based management to organize Kan River valley. Among sub criteria in natural- ecological factor, flood, domain movements and building and texture of soil are the most important respectively 23%, 18% and 11.5% also in social factor, participation, security and public trust have the importance respectively equal to 49% 31% 19%. In economic factor, environmental assets and stakeholder’s economic participation have the same importance. Based on this research, management factor (organizational pattern and the method of management) is the most important in ecosystem based management. But this approach, the management pattern and intervention to organize this river valley, need comprehensiveness and integrity of the subject (nature, society, management and economic), purpose (protection, resuscitation and use), factors (government, city council, municipality, private sector and people), duties (policy making, planning, designing and perform), method (collaborative), tools (knowledge, skill, rule, program, budget, machinery and materials) and management domain. Use of these factors and criteria need some infrastructure and reforms. The most important reform is reform of management structure, production of subject matter and topical program special to organize river valleys by ecological approach to release Kan of loading and contradictory grabbing.so this management can follow protection, resuscitation, sustainable use and continuity of ecological services.

    Keywords: ecosystem, river, river valley, ecosystem based management, analytic network process
  • Behzad Raygani*, Fargol Goodarzi, Ahmad Talebi, Mohammad Talaeian Araghi, Hadi Hashemi Pages 33-48

    In this research, the evaluation of possible effects of land use change on water quality in Shadegan wetland has been provided with the help of remote sensing data. The purpose of this research was to evaluate and compare user variations in 2000 and 2015 using Landsat satellite imagery (with ETM and OLI sensors) from the study area and processing them in the ERDAS software environment using the unstructured classification method during a period of 15 years old has been investigated. To determine the cause of the changes occurring in the wetland, the water quality of the wetland was evaluated through the help of modeling. Vegetation in the wetland has been rising rapidly, indicating water pollution, an increase in the nutritional status and the early disappearance of this international wetland. With the help of this article, it can be admitted that the development of agricultural lands around the shadegan wetland from 2000 to 2015had caused an increase in pollution in the region, according to available agricultural wastement containing  quantities of herbicides and pesticides which has led to an increase in the growth of algae in the wetland, which has led to an increase in temperature and eventually the death of wetlands and aquatic animals so after selecting images and assign them in 5 classes, the change wetland  maps were obtained during a 15 year various sources were used to determine the best regression model for determining water quality changes in the following, the images were placed in the models and their mean and standard deviation were obtained. The result of the research showed that the Landsat sensor shows the water quality well and can be used to determine the changes. The development of agricultural lands leads to an increase in the eutrophication phenomenon in the wetland and, in the end, reduces the quality of water indicators. In the end, causes quality loss of water.

    Keywords: Landsat sensor, agricultural, landuse, eutrophication, wetland, shadegan
  • Sharifinia Zahra* Pages 49-66

    Concerns over the social, economic, and ecological impacts of climate change on human habitat have increased over the last few decades (McGranahan et al, 2007). According to the UN report, water shortages will occur in the near future in 18 countries, and by 2025 more than two-thirds of the worldchr('39')s population is projected to be in serious water shortages (Pozzi et al, 2013, 191 112; World Bank, 2008, 124). On the other hand, the number of disasters has increased over the past 20 years, reaching 400 from 200 accidents (Pittman et al, 2011, 83,94; Molen et al, 2011, 765-773). In this regard, droughts, the most dangerous natural disasters, affect a wide range of climates and ecosystems, and the geographical areas affected by them have increased rapidly in the last four decades (Kamara et al., 2018, 2318). Drought is a major threat to households and community’s dependent on agriculture for livelihoods (Anthopoulou et al, 2017). Because livelihoods in agricultural-dependent societies are more dependent on climate change (Pittman et al., 2017. ( It is central to the city of Neka; it requires a holistic perspective. The type of applied research and methodology used is descriptive-analytical. Librarian and field method (observation, questionnaire) were used to collect the required data. In order to assess the resilience of rural areas to drought in two economic dimensions (ability to return to employment and income generation and compensation of costs and losses) and in social dimension (awareness, knowledge, skills and preparedness and participation and Collaboration) Designed and developed a Likert-type questionnaire ( 1 very low, 5 = very high). The statistical population of this study is based on census of 6947 households in 24 villages with error of 0.07, 191 questionnaire as sample size and based on the relationship of sharing ratio of the number of samples in each village is specified and in villages less than 7 samples, the number has been upgraded to 7. Finally, 233 samples were used as the sample size based on questionnaire completion and analysis and were randomly distributed and distributed among households. To assess the validity of the questionnaire, the experts were first provided with validity and the validity of the research instrument was measured and the final indices and statements were extracted. The questionnaire developed at this stage was pre-tested in the study area and after confirmation of trust or reliability (Cronbachchr('39')s alpha value of 0.84) the questionnaire was finalized for field research. Descriptive (inferential) and inferential statistical methods (single sample t, Friedman, cluster analysis) and VASP, ARAS and VIKOR models were used to analyze the data. Therefore, in order to evaluate and measure resilience in rural areas, firstly, annual moisture status was investigated based on SPI, SDI and GRI indices. Therefore, the moisture status of the study area during the 13-year statistical period (2006-2007) using the data of 9 Standard Precipitation Index (SPI) rain gauge data, the data of the discharge rate of 6 rivers Surface Flow Index (SDI) and the values Water level level of 9 piezometric wells of GRI index was calculated in DrinC software environment.  Iranchr('39')s position on the dry belt and the persistence of droughts over the past two decades have led to the emergence of drought-related crises, especially for villagers who are heavily dependent on water for production, due to climate change. Droughts in the study area were also not exempt from this rule and resulted in adverse effects beyond the normal state and the risk of drought among rural farmers, which could be due to their low level of resilience to this risk. Be it. Therefore, the present study aimed to investigate the economic and social effects of this phenomenon on the status of rural resilience against drought hazards. The results showed that among the sample villages, in the economic dimension, the highest average belonged to Tavaza Abad village of Bostan Khel with average of 3.11 and the lowest average belonged to Plazhartesh village with average of 1.63. In the social aspect, the highest average belongs to the village of Dukhaelo with a mean of 3.54 and the lowest average belongs to the village of Plazhartesh with an average of 1.55. Also, the average real perception of the respondents is less than three and is moderately low, indicating that rural resilience to drought is low.

    Keywords: Rural Areas, Resilience, Drought, Gharaghgan Village
  • Javad Sadidi*, Zahra Judaki, Hani Rezayan Pages 67-80

    Nowadays, due to the complexity of interior space of buildings, the need arises for indoor navigation inside such spaces. Indoor navigation systems may be helpful for emergency evacuation of the crowd in natural hazards such as earthquake as well as human-made disasters. These systems can also act as a decision support system for officials. Literature survey on indoor navigation services shows that a large number of researches have been conducted around designing and implementing such systems but automatic indoor spaces topology extraction of the current building information models remains as a challenge. This research aims to introduce, design and implement a web-based indoor navigation system using CityGML data model in LOD4 (level of detail) to overcome the mentioned problem. The architecture of the current research is a browser-based web application service such that the data model processing and graph creation is implemented on the server side, the client interface and calculated path are represented on the client side (browser). Through the CityGML data model processing, firstly, the building navigable spaces such as room floor, doors and stairs are extracted and then, each space as a node and the connections between the nodes are defined as edges, are imported to the navigation graph. Programming on the server side has been performed by Python language and web development languages including HTML (Hypertext Markup language), JavaScript, JQuery and AJAX are used on the client side. Cesium virtual globe has been exploited to display the data model and the calculated route. To evaluate the introduced methodology and designed service, a three floor house with CityGML format in LOD4 was used as the case study. Generally, a client can request a 3D calculated path by selecting the source and destination points on the client browser. The server receives the request and returns the response as a 3D line to the client browser on the Cesium environment. In addition, a descriptive graphical user interface for visual inception of the route is offered to the users on their browser. One of the advantages of the designed web application is that, the service is implemented on the browser. Hence, all devices equipped with a browser have possibility to run the 3D routing service. Besides the mentioned cross-platform capability, average expectation time of the graphical interface loading, data module processing and path finder module are 7.03 milliseconds, 12.42 seconds and 2.44 seconds respectively that visits a valuable criteria in emergency situations like an earthquake phenomenon. Regarding this fact that CityGML is a new data model and supported by a few software, the introduced architecture causes less implementation costs as well as automation of these systems.

    Keywords: Indoor Navigation, indoor space, Graph CityGML, Topology, Semantic, Geometry
  • Ali Eshghei*, Hossein Nazmfar, Ata Gafari Pages 81-101

    Earthquake as one of the most devastating and destructive natural hazards; especially in developing countries, it has been a long time ago With the collapse of buildings and urban infrastructure, Imports a lot of damage to property and assets in urban areas and around them. In response to this, international organizationschr('39') strategies to mitigate disasters have made their societies resilient to natural disasters. And considers it within the framework of the Higgo for the years 2005-2015. In fact, the goal of this approach is to reduce the vulnerability of cities and to strengthen citizenschr('39') abilities to deal with the dangers of threats such as natural disasters. Considering that the area of ​​a Tehran city due to its proximity to faults such as Mashaa fault, North Tehran fault Also, the effects of faults in and around the region such as Niavaran fault, Mahmoodieh fault and Darabad fault (Banamieh) are located in a region with a high seismic hazard. Assessment of resilience of the region to earthquake risk and resilience of the region In order to reduce the risks of earthquakes in this area is very important. Accordingly, the present study was conducted with the aim of assessing the resilience situation of the 10th district of Tehran municipality district against earthquake. The method of this research is descriptive-analytical with a purposeful purpose. The research area of ​​the 10th Region is a municipality of Tehran. The raw data used by the Tehran Municipality Information Technology Organization has been obtained. To determine the relative importance of each component used in research According to experts from the Urban Planning Area, the Network Analysis Process (ANP) has been used in the form of Super Decisions software. Then, to rank 10 areas of a Tehran municipality district against earthquake, Multi-criteria decision making models (MCDMs) including TOPSIS, VIKOR, HAW and SAW models have been used. Considering that different methods have been used to rank the areas Different results have been achieved, to overcome the contradictions between the various ratings of the regions in each of the models, and a single result has been used to rank the areas of the congregationchr('39')s integrated model. Finally, in order to speak, the results of the model used in the ArcGIS environment were mapped. In this research, for the spatial analysis of the resilience of the 10 district areas of a Tehran municipality from the results four models (TOPSIS, VIKOR, HAW and SAW) were used. Based on the results of the TOPSIS technique, areas 8, 3 and 2 of resilience are large, areas 7 and 4 of the moderate resilience, Areas 5, 1, 6 and 10 have low resilience and area 9 has very little resilience against the earthquake. Based on the results of the VIKOR model, areas 3 and 4 of the resilience, regions 2, 7, 5, 9, 8, 6 and 10 of the moderate resilience Medium and area one have low resilience against earthquake. Based on the results of the HAW model, area 3 of the high resilience, regions 2, 7, 8 and 4 of the moderate resilience and areas 10, 1, 6 and 9 are of low resilience. In this model, no area has been found to be very resilient. Based on the results of the SAW model, regions 3, 2, 8, and 7 are in the range of many resiliences, regions 5 and 4 in the moderate resilience range, Area 9 is in the low resilience range and areas 10, 6 and 1 are in the low resilience range against earthquakes. In this study, we evaluated the resilience situation in the districts of Tehran municipality district in an earthquake Multi-criteria decision-making methods including TOPSIS, VIKOR, HAW and SAW were used, Then a CONDORCET integrated model was used to achieve a single result of these analyzes. The results of the Canadian model, which is the result of a combination of the final results of the models (Tapis, VIKOR, HAW and SAW), show that Areas 2, 4, 5, and 3 are of high resilience, areas 7, 8 and 1 of the moderate resilience, 10 and 6 of the resilience, and area 9 of the resilience is very low against earthquakes. Which should be prioritized in future plans. Although it is possible to assess the vulnerability of urban areas by using different models and mapping them in the regionchr('39')s resilience to the earthquake crisis, a significant part of post-crisis casualties fell but this will not be achieved until the authorities are seriously determined.

    Keywords: resilience, TOPSIS, VIKOR, HAW, SAW, Kandrst
  • Soraya Yaghobi, Kamran Karimi*, Marzaban Faramarzi Pages 103-120

    Nowdays desertification is a disaster in many countries , especially in developing countries. This problem includes natural factors and improper human activities. According to the expansion of desertification, providing the appropriate management methods will be reduced desertification intensity and its expansions. In this way, knowledge of processes of desertification and factors causing and  the intensifier it and also awareness of intensity and Weakness the processes and factors that are important and necessary   that should review and evaluate. Recognition criteria and indicators for provide a model to show the process of desertification and for determine one of the  best reason effective factors for prevent the spread of desertification factors is necessary. To knowledge and Trend of desertification and separation of  vulnerable  areas versus degradation factors .we should indentifi and evaluat  criteria and indicators affecte  at desertification. Therefore in this study of  the Iranian model IMDPA to assess trends and Comparison of desertification in recent years has used. The studied area of  Dehloran plain is located in southeast of Ilam province (47◦ 02′ 16″ to 47◦ 25′ 07″ E and 32◦ 48′ 33″ to 32◦ 18′ 48″N) with an area of 54252  hectares, With precipitation  average 251.6 mm and Abbas plain is located in south of Ilam province(47◦ 37′ 55″ to 47◦  50′ 57″ E and  32◦ 17′ 77″ to 32◦ 29′ 25″N) with an area of 34104 hectares With precipitation  average 227.1mm. In this study, in dehloran plain of six stations in this Inside and outside the area also in Abbas plain of five  stations outside the area  used to measure the amount of rainfall in different seasons of year. In this study, to assessment  and Comparison of desertification in two study area of the Iranian model IMDPA used. In this study, of climate criteria, were used. which according to the IMDPA model for this criteria, indexes are considered for evaluation e.t.c: Climate criteria: (1) the amount of annual rainfall 2-drought indexe(SPI) 3. continuing drought In IMDPA model  All measurements  do in this work  units. To this end, first, working unit maps (geomorphologic facies) were created using slope, geology, and land use maps. a map was generated for each index according to assigned weights, such that the qualitative map of the desired criteria were obtained using the geometric mean of indicators. The results earn  of  evaluation  of desertification  showed that  in the period  2005-2009  weight average of climate criteria is same with 1.50 all of the region are in the classe Middle sub class 1 and class low sub class3 . in the period  2010-2014  Also  weight average of climate criteria is same with 1.88 in classe Middle sub classes 2 and 3.  Also weight average of climate criteria in Abbas plain In the first period is same with 1.92  in the classe Middle sub classe2. Also In the second period with weight average is same 2.3 in classe Middle sub classes 2 and 3. The results showed that SPI index, as the most effective indexes, in plain Abbas In the first and second periods with the weighted average 3.04and 3.2 in the intense class under class 2 and 3. in front in Dehloran plain SPI index in the first and second periods with weighted average of 1.93 and 2.25 in the moderate classe and sub-classes 1, 2 and 3 and intense sub-classe 1. In this study, to assess and Comparison of desertification Dehloran and Abbas Plains to provide regional model has done. . In this way  of  a criteria, also important and effective indexes belonging to this criteria of desertification used in dehloran and Abbas plains . The obtained results of the analysis criteria and Indexes indicated that in dehloran and Abbas plains in the first period ( 2005-2009) And second period (2010-2014)  between  indexes  the amount of annual rainfall, standard precipitation index (SPI) and drought duration Evaluated on the areas respectively standard precipitation index (SPI),  rainfall and drought duration index the most important factors in exacerbating desertification. Can be concluded that the intensity of desertification in Abbas plain compared to dehloran plain terms of climate is In more adverse conditions. In general, it can be concluded that desertification would intensify in future decades.

    Keywords: Desertification, IMDPA, Climate, Abbas Plain, DehloranPlain
  • Nima Sohrabnia*, Bohlol Alijani, Mehry Akbari Pages 121-136

    In this essay, we investigated the effects of climate change on the rivers of selected basins of Guilan province, one of the northern provinces of Iran for the period 2020 to 2050 under three climate scenarios: RCP2.6, RCP4.5, RCP8.5. For this purpose, rainfall and temperature data from 45 climate data stations and 20 hydrometric stations from 1983 to 2013 were used. The average precipitation and temperature at basin level were calculated by drawing both Isohyet and Isothermal lines by usage Kriging method. Mann-Kendall and Sen’s slope estimator tests were used to determine the significance of the data trends and their slope, respectively. The results showed that temperature has increased in all catchments during the study period and this trend was significant in most of them but no significant trend was observed for precipitation. Discharge has also decreased in most basins and this trend was significant in Shafarood, Navrood and Chafrood basins. However, for future periods, precipitation is not significant in any of the climate scenarios, but the temperature is increasing in all scenarios except for the RCP2.6 scenario. Rivers discharge in the RCP2.6 scenario is not significant in any of the basins, but in the RCP4.5 scenario the Shafarood and Ghasht-Roodkan catchments have a significant reduction in the 95% confidence level. In the RCP8.5 scenario, the Chafrood and Shafarood basins have a 99% confidence reduction trend. Population and technology growth, increased water consumption and climate change have led many researchers to study and model water resources in the present and future periods. Especially in areas like Iran that are facing a lot of water stresses. The purpose of the present study, which was carried out in the Guilan province, is to provide information on the present and future status of surface water resources, and to prepare them for facing the problems of potential water resources exploitation. In this study 45 synoptic, evaporative and rain gauge stations and 20 hydrometric stations data with sufficient statistics were used. The period of study is also between 1983 and 2013. In this regard, after calculating the average precipitation and temperature values of each basin using Kriging model, first, the annual average of precipitation and temperature values ​​of each basin were calculated. Then, multivariate regression was used to obtain the regression equations between precipitation, temperature and discharge data, then by using SDSM model and climate scenarios (RCP2.6, RCP4.5, RCP8.5) future temperature and precipitation data were generated. By placing these generated data in the Created regression equations, the discharge of the rivers was calculated for the period 2020 to 2050. The trend of time series and their slope were analyzed respectively by Mann-Kendall and Sense tests. The study of the annual average precipitation trend of the selected catchments during the study period showed that all the basins had no significant trend at any of the confidence levels (95% and 99%). However, for the temperature there is an increasing trend. In Chafrood, Zilaki, Chalvand, Lavandevil, Tutkabon, Chubar, Lamir, Hawigh, Dissam, Shirabad, Ponel, Samoosh, and Polrood basins there is significant trend at 95% confidence level. For the Hawigh River basin there is significant trend at 99% confidence level. Also in most of the basins there is a downward trend of rivers discharge. In addition, in the three basins of Chafrood, Navrood and Shafarood, there is a significant decreasing trend at 95% confidence level, which is also significant at 99% confidence level for Navrood and Shafarood rivers. Analysis of future data showed that precipitation is not significant in any of the climate scenarios, but the temperature is increasing in all scenarios except for the RCP2.6 scenario in RCP2.6 scenario. For rivers discharge there was no significant trend in any of the basins, but in RCP4.5 scenario there is a significant decrease in 95% confidence level in Shafarood and Ghasht-Roodkan. Also in the RCP8.5 scenario, a significant decreasing trend of flow discharge at 99% confidence level is observed for Chafrood and Shafarood basins. Finally, the catchments were grouped according to the level of risk involved with decreasing discharge. The results of grouping showed that most of the basins in the three scenarios were in the medium risk group but Shafarood, Chafrood and Ghasht-roodkhan watersheds have higher risk than the other watersheds, respectively. Investigation of river discharge trends for the period 2020 to 2050 in different scenarios showed that the basins of Ghasht-roodkhan, Chafrood and Shafarood are more sensitive to climate change than other basins. Overall, escalating temperature trends in future and precipitation irregularities can create very difficult conditions in future to use these resources. Especially, this studychr('39')s concordance with other studies in Iran and the study area confirms that such crises are more likely to occur..

    Keywords: Climate Change Scenarios, Rivers Discharge, Man-Kendall, Sen’s Slope estimator, Guilan Province
  • Koohzad Raispour*, Yones Khosravi Pages 137-152

    Air pollution is one of the most important problems in many countries in the world, which, besides the environmental damage and human health, imposes many adverse social and economic impacts. Therefore, considering the vital importance of air and the rising course of increasing the contaminating agents in recent decades, it is necessary to study the elements and their pollutant gases in order to be aware of the existing situation and to adopt the necessary solutions. The phenomenon of atmospheric air pollution in Iran, as part of the worldchr('39')s atmosphere, is one of the goals of the industrial revolution, which has been increasing day by day as industrialization; population growth and urbanization have grown dramatically. Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air. In the atmosphere, it is spatially variable and short lived, having a role in the formation of ground-level ozone. Carbon monoxide consists of one carbon atom and one oxygen atom, connected by a triple bond that consists of two covalent bonds as well as one dative covalent bond. Carbon monoxide is produced from the partial oxidation of carbon-containing compounds; it forms when there is not enough oxygen to produce carbon dioxide (CO2), such as when operating a stove or an internal combustion engine in an enclosed space. Carbon monoxide is one of the most dangerous air pollutants. Due to its importance, many techniques and methods have been used to monitor the Earthchr('39')s atmosphere in recent years. as well as, the use of satellite data has become widespread because of the availability and availability of features such as spatial, temporal and spatial resolution. In this study, the data from Aqua / AIRS Carbon Monoxide data can be used to study the rate and trend of carbon monoxide gas changes in the atmosphere of the entire world, including Iran.The relevant data in NetCDF format, with one-day and 13.5 x 13.5km spatial resolution of during the 16-year statistical period (2003-2018), was extracted from using ArcGIS software And Grads are processed, represented, analyzed. The results indicate that the amount of carbon monoxide was reduced during the monthly and annual time series. Of course, monthly and seasonal variations have been impressive. Monthly, the highest concentration of carbon monoxide in January, February and March, and the lowest in August, September and October. Among the seasons, the highest and lowest levels of carbon monoxide were observed in the seasons of winter and summer, respectively. In spatially, the highest amount of surface carbon monoxide with an average of 150 ppb above the city of Tehran and the coastal area of the Caspian Sea and its lowest level with an average of 115 ppb on the Zagros heights was observed. The results clearly show a clear picture of the dispersion of carbon monoxide gas in the horizontal and vertical direction of Iranchr('39')s atmosphere. Based on the results obtained from the monthly carbon monoxide data collected during the statistical period (2003-2018), conducted in a three dimensional and regional area extending to the geographical area of Iran, The average surface carbon monoxide of more than 150 ppb above the Tehran metropolitan area and northern coast of Iran is less than 115 ppb on Zagros altitudes. Among other results, there are significant differences between the monthly carbon monoxide average in the surface troposphere of Iran, so that in the twelve months, the highest amount of carbon monoxide was observed in cold months and the lowest was observed in the warm months of the year, respectively. Seasonally, the highest level of seasonal carbon monoxide has been observed in winter and its seasonal season has peaked in summer. The results of vertical profiles (vertical aspect) of carbon monoxide changes in Iranchr('39')s atmosphere in line with latitude and longitude indicate the maximum carbon monoxide concentration at lower levels of barley so that the maximum amount of carbon monoxide in the Iranian atmosphere is concentrated in the lower levels and Rarely exceeds the level of 250 hPa. Also, the results indicate that the rate of carbon monoxide emissions in the atmosphere of Iran has decreased, so that in the last years of the statistical period, about 30% of the amount of carbon monoxide in the atmosphere of Iran has been reduced, compared to the early years of the statistical period.

    Keywords: Air Pollution, Carbon Monoxide, AIRS, Remote Sensing, Iran
  • Iraj Ghasemi, Fatemeh Razzzaghi Borkhani*, MohammadAli Mohammadi Gharehghani Pages 153-168

    Every year, a number of rural settlements are affected by natural disasters or human factors, in such a way that life in these settlements is dangerous, and even, in some cases impossible. Thus, displacement programs in the form of leaving the main settlement and creating new settlements in another place will be considered by planners and managers. These programs are not without consequences and affect different aspects of the residentschr('39') lives. Identifying these consequences can provide sufficient experience and evidence for managing other displacement projects. Accordingly, the current study focuses on displacement phenomenon in Balouch Abad village in order to identify the consequences of displacement by discovering the contexts of displacement and explaining the residentschr('39') perception about the causes of this phenomenon. In general, empirical literature on the topic shows that the consequences of displacement, both positive and negative, occur in all dimensions of human life, and that a change in any dimension can change other aspects of the life of the target community. Investigating all dimensions of displacement has been considered in a few studies, in which less attention has been paid to the existing contexts, perceptions and planning and management structures. Therefore, this study contributes to the relevant literature by querying these contexts and providing solutions for displacement programs in the future. The aim of this study is to understand the perception of the residents of Baloch Abad village about the causes and consequences of residential displacement using a critical ethnographic approach. This approach is suitable for studying phenomena such as residential relocation, which are the result of the decisions of the planning system and in most cases is faced with the unwillingness and lack of interest of stakeholders (residents). In fact, the critical ethnographic approach seeks to examine inequality, conflict, and power in a subculture. Thus, the process of displacement due to integration with a kind of conflict between residents’ willingness and the planning system, can be well explained using this approach. Data was collected using in-depth interviewing, non-participant observation, and focus group techniques. The experience of displacement in Balouch Abad village indicated that the consequences of displacement do not occur independently and are correlated with each other. In other words, the negative consequences in terms of social and economic are rooted in the physical- consequences, and on the other hand, the social consequences are also rooted in economic consequences. On this basis, the lack of attention to the proportion of housing based on social relations has been the prelude to occur other negative consequences. The mismatch between the structure and size of dwellings and their occupational requirements (animal husbandry) has led to the collapse of subsistence foundations. Evidence also showed that maintaining neighborly relations in the village was influenced by the physical structure and system of land transfer. As a result, it can be stated that the various consequences of residential displacement can occur through planning and physical management. This study is based solely on the evidence, contexts and perceptions of key stakeholders who are residents of Balouch Abad village; however, the part of the challenges of displacement in this village is due to managerial actions that were not considered in this study. Therefore, it seems that mere focus on the view of stakeholders is one of the main limitations of this study, which is necessary to pay attention to this limitation. In this regard, it has been tried to provide sufficient evidence on manures of management the displacement process through the technique of triangulation. Future studies may take into account the views of both experts and stakeholders at the same time.

    Keywords: Residential displacement, Balouch Abad village, natural disaster, contexts, consequences of displacement
  • Aliakbar Shamsipour*, Ayoub Jafari, Hesam Bostanchi Pages 169-185

    The blizzard incident is one of the climatic hazards that occurs due to the combination of other climatic factors such as temperature (below zero), snow and wind (at 15 m/s). In this research, the conditions of blizzard in Northwest of Iran are carried out using statistical methods. By analyzing all the meteorological codes of the blizzard (36, 37, 38 and 39) during the statistical period from 1987 to 2016 for 11 synoptic stations of the study area, codes with severe blizzard (37, 39) were selected. Then, using the geopotential height, wind and Leveling temperature of 500 and 850 hpa, obtained from the NCEP/NCAR open source database, the synoptic patterns of blizzard incident analyzed. Statistical analysis of the relationship between the effects of geographic factors on severe blizzard has shown that the factor of height has the greatest effect on intensity, increase and incident spatial differences of this phenomenon. The study of the synoptic patterns of the incident of the blizzard phenomenon showed that five main patterns play a role in creating it in the region. The synoptic patterns of development include the formation of a low cut-off center, a long landing passage from Iran, the formation of a relatively deep and drawn Mediterranean East, The rectangular system is a rex-shaped system and is an umbilical bundle system. Among the patterns obtained, the patterns that were bundled were, the most important role in the survival and transfer of flows associated with cold, and other patterns, despite the frequency they had, were periodically of severity and weakness. Keywords: Blizzard; North West; Wind speed; Temperatures below zero; Synoptic patterns Human life is always affected by climatic phenomena, especially the hazards of the two variables of temperature and wind. One of the most important simultaneous phenomena of these two variables is the blizzard, which is caused by heavy snow, stormy winds, and very low temperatures. This climate risk can cause damage to various areas of horticulture, agriculture, urbanization, transportation, and so on. This phenomenon is present in regions such as Canada and North America with a cold weather wave that results from turbulence in the winters and damages the lawns in these areas. There are plenty of local storm in the polar regions and it lasts for a few days. For example, the wind in the Adelie land in the Antarctic is so severe that the area is known as the storm Land. In Iran, the most significant blizzard occurred in mid-February 1350, resulting in the deaths of more than 4,000 people across the country. In this research, considering the characteristics of the blizzard phenomenon at the time of occurrence (severity, continuity, expansion, and time of occurrence), the study has been conducted to determine the statistical synoptic patterns in the northwest region. In this research, the studied area is northwest of Iran, which includes 6 provinces (Ardebil, West Azarbaijan, East Azarbaijan, Zanjan, Kurdistan, Kermanshah, Hamedan). In order to study, the days with the blizzard phenomenon in the form of 3 hours and in codes of this phenomenon (36, 37, 38 and 39), were obtained from the establishment of the stations studied by 2016. In the following, for precise examination, stations with 30 years of statistic from 1987 to 2016 were identified and the statistical (frequency, daily, monthly and annual frequency) codes 39 and 37 were studied. Finally, the relationship between blizzard with the latitude and elevation in the studied stations was determined. To assess the statistical results, the correlation coefficients (R) and coefficient of determination (R2) were used. In the second part, the identification of synoptic patterns was done by Principal Component Analysis in MATLAB software and ocular method. The criterion for identifying synoptic patterns, the days where codes 37 and 39 are more than 1 time (3 hours) within 24 hours or two days behind each other at the stations studied. In order to determine the patterns, at first, the average geopotential data of the 500-hpa level from 1987 to 2016 were obtained from a range of 10-70 degrees north latitude and 0-80 degrees east longitude with a spatial resolution of 2.5 * 2.5 from the NCEP / NCAR data. Statistical analyzes on the relationship between the effect of geographic factors on severe blizzard showed that the factor of height had the greatest effect on the intensity, magnitude and spatial differences of this phenomenon. In sum, the most important factor in the occurrence of this phenomenon is due to atmospheric conditions and synoptic patterns of the region. In this study, the most frequent occurrence of codes 37 and 39 in all stations studied was at Sardasht station and Khalkhal station, respectively. Also, the statistical study of the frequency of the annual and monthly occurrence of each code showed that code 39 in 1990 and code 37 in the years 1989 and 1990, as well as in January, had the highest frequency of each of the two codes. Investigating the patterns of the occurrence of the blizzard phenomenon showed that five main patterns have contributed to its creation in the region, the first pattern due to the formation of a low cut-off center, which, with the cold weather in Central and Eastern Europe, has reduced the temperature in the northwest. The second pattern is due to the high landing passage from Iran, which has crossed the descent from a cold and cold weather zone from Europe to Iran. The third pattern is the location of the studied area in the relatively moderate, dragged, eastern Mediterranean wavelength, causing cold weather to fall to the northwest. The fourth pattern, with the formation of a Rex-type blockade on the Mediterranean, has led to the transfer of cold air from Eastern Europe, Kazakhstan, and high latitudes to Iran. The fifth pattern, with the formation of a blockade, has caused cold weather in northern Europe and Central Asia to enter the country from the north, causing a drop in temperature in the region. Among the known patterns, the patterns that were blocked (pattern 4 and 5) played the most important role in the survival and transfer of cold fluxes and even drawn to lower latitudes. Other patterns, despite frequent periods, provide conditions for the occurrence of this phenomenon and, unlike the blocking patterns, have had severity and weakness.

    Keywords: Blizzard, North West, Wind speed, Temperatures below zero, Synoptic patterns
  • Hassan Lashkari*, Neda Esfandiari Pages 187-206

    Atmospheric rivers (ARs) are long-narrow, concentrated structures of water vapour flux associated with extreme rainfall and floods. Accordingly, the arid and semi-arid regions are more vulnerable to this phenomenon. Therefore, this study identifies and introduces the highest precipitation occurred during the presence of ARs from November to April (2007-2018). The study also attempted to demonstrate the importance of ARs in extreme precipitation, influenced areas and identifies the effective synoptic factors. To this end, integrated water vapour transport data were used to identify ARs, and documented thresholds applied. AR event dates were investigated by their daily precipitation, and eventually, ten of the highest precipitation events (equivalent to the 95th percentile of maximum precipitation) associated with ARs were introduced and analyzed. The results showed that most ARs associated with extreme precipitation directly or indirectly originated from the southern warm seas. So the Red Sea, the Gulf of Aden and the Horn of Africa were the major source of ARs at the time of maximum IVT occurred. Synoptically, seven AR events formed from the low-pressure Sudanese system and three events from integration systems. The subtropical jet was the dominant dynamic of the upper troposphere, which helped to develop and constant of ARs. Moreover, the predominant structure of jets had a meridional tendency in Sudanese systems, while it was a zonal orientation in integration systems. The intense convective flows have caused extreme precipitation due to the dominance of strong upstream flow besides having the highest moisture flux. The station had the highest precipitation has been located in the eastern and northwestern region of the negative omega field or upstream flows.

    Keywords: ARs, extreme precipitation, synoptic analysis, IVT, Iran