فهرست مطالب

محیط شناسی - سال چهل و پنجم شماره 1 (پیاپی 89، بهار 1398)
  • سال چهل و پنجم شماره 1 (پیاپی 89، بهار 1398)
  • تاریخ انتشار: 1398/03/04
  • تعداد عناوین: 12
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  • مسعود شاکرمی*، صفر معروفی صفحات 1-16
    تحقیق حاضر به صورت آزمایش فاکتوریل در قالب طرح کاملا تصادفی در شرایط لایسیمتری با سه نوع آب آبیاری: آب معمولی (1W)، فاضلاب خام (2W) و فاضلاب تصفیه شده (3W) و سه سطح لجن فاضلاب: 0 (1S)، 50 (2S) و 100 (3S) تن در هکتار انجام شد. لایسیمترها، با خاک دو لایه پر و گیاه نعناع در آنها کشت گردید. عملکرد، میزان عناصر مغذی گیاه و میزان فلزات سرب، نیکل و کادمیم در گیاه (شاخساره) و خاک (اعماق 10 و 40 سانتیمتری) تعیین گردیدند. نتایج نشان داد کاربرد فاضلاب و لجن، میزان فلزات خاک را افزایش، به طوری که نسبت به شاهد، تیمار 3S2W میزان سرب، نیکل و کادمیوم را به ترتیب 304، 375 و 208 درصد افزایش داده است. همچنین نتایج نشان داد کاربرد فاضلاب و لجن سبب افزایش معنی دار وزن های تر و خشک و همچنین میزان سرب، نیکل و کادمیوم گیاه می گردد. دامنه تغییرات وزن های تر و خشک گیاه به ترتیب 161- 31 و 54- 11 گرم در لایسیمتر، دامنه تغییرات نیتروژن و فسفر به ترتیب 93/2- 12/1 و 56/0- 19/0 درصد وزن خشک گیاه، دامنه تغییرات پتاسیم (85/3- 05/1)، نیکل (71/0- 02/0)، سرب (57/0- 01/0) و کادمیم (3/0- 01/0 میلی گرم در کیلوگرم وزن خشک گیاه) گیاه، در نوسان می باشد.
    کلیدواژگان: فاضلاب، لجن فاضلاب، نعناع، پارامترهای رشد، عناصر سنگین
  • سمیرا مرادلی، عباس خوشحال* صفحات 17-33
    در این تحقیق با ساخت یک پایلوت رآکتور ناپیوسته متوالی و استفاده توامان از میکروارگانیسم ها و ریزجلبک کلرلا ولگاریس، کارایی این سیستم در تصفیه فاضلاب بهداشتی نیروگاه سیکل ترکیبی یزد مورد مطالعه قرار گرفت. بدین منظور اثر pH، دما، غلظت COD در فاضلاب ورودی و دبی هوا بر میزان حذف COD و غلظت باقیمانده آن در پساب بررسی گردید. شرایط بهینه برای حذف COD از فاضلاب بهداشتی در pH برابر 8، دمای oC 30، COD فاضلاب ورودی mg/l 600 و دبی هوای l/min 50 به دست آمد. تحت شرایط بهینه مقدار COD باقیمانده در پساب به mg/l 34 رسید که نشان دهنده افزایش کارایی سیستم مورد نظر است. همچنین به منظور مدل سازی فرآیند و پیش بینی غلظت COD باقیمانده، از یک شبکه عصبی مصنوعی پرسپترون چند لایه با الگوریتم آموزش لونبرگ- مارکوارت استفاده شد. توابع انتقال tansig برای لایه میانی، purelin برای لایه خروجی و تعداد 7 نرون در لایه میانی به عنوان مدل بهینه برای این شبکه انتخاب گردید. نتایج حاصل از مدل سازی شبکه عصبی مصنوعی تطابق خوبی با داده های آزمایشگاهی داشت. برای این مدل سازی، مقادیر ضریب همبستگی (R2) و مجذور میانگین مربعات خطا (RMSE) به ترتیب 944/0 و 034/0 به دست آمد.
    کلیدواژگان: تصفیه فاضلاب، رآکتور ناپیوسته متوالی (SBR)، ریزجلبک کلرلا ولگاریس، مدل سازی، شبکه عصبی مصنوعی
  • ملیحه دشتی، غلام رضا دهقان*، علیرضا ختایی صفحات 35-45
    رشد جمعیت جهانی و افزایش نیاز به صنایع مختلف منجر به تجمع انواع مختلف آلاینده ها در محیط زیست و منابع طبیعی شده است. در این میان صنایع رنگ نساجی در طول فرآیندهای رنگرزی میزان قابل توجهی فاضلاب رنگی را به محیط زیست تخلیه می کند که پساب آن حاوی بسیاری از آلاینده های بازدارنده و اکوتوکسیک می باشد. در این کار پژوهشی، پارامترهای فیزیولوژیکی و بیوشیمیایی (میزان رنگیزه های فتوسنتزی و ترکیبات فنولی، فعالیت آنزیم های سوپر اکسید دیسموتاز، کاتالاز و پراکسیداز) برای سنجش میزان سمیت ماده ی رنگزای مالاکیت سبز در جلبک پر سلولی شارا مورد ارزیابی قرار گرفت. فعالیت آنزیم های آنتی اکسیدان سوپراکسید دیسموتاز 2/41 درصد و پراکسیداز 44 درصد در غلظت های متفاوت از مالاکیت افزایش یافت. در مقابل، فعالیت آنزیم کاتالاز در غلظت های متفاوت ماده رنگزا کاهش 9/31 درصدی داشت که نشان می دهد پاسخ جلبک شارا به تنش اکسایشی، در بیان ژنهای این سه آنزیم متفاوت می باشد. ترکیبات فنولی 9/72 درصد و کاروتنوئید کل 48 درصد در غلظت های بالای مالاکیت سبز افزایش یافت در حالیکه میزان کلروفیل a و b در مالاکیت سبز کاهش 3/18 درصدی نشان داد. ولی میزان مالون دی آلدئید، به عنوان شاخص اکسیداسیون لیپیدی، تغییر معنی داری نشان نداد.
    کلیدواژگان: جلبک شارا، مواد رنگزای سنتتیک، گونه های فعال اکسیژن دار، آنتی اکسیدانها
  • مینا رفعتی، محمد پازوکی*، حسین قدمیان، علی جلیل زاده، آذرمیدخت حسین نیا صفحات 47-63
    این پژوهش با هدف اجرای چهار مدل حذف آلاینده و ارائه مناسبترین مدل بیولوژیکی بهمراه ضرایب سینتیکی منطبق با شرایط فاضلاب تولیدی تصفیه خانه فاضلاب جنوب تهران انجام شده است. ضرایب سینتیکی امکان مدل کردن فرایند تصفیه و پیش بینی کیفیت پساب خروجی را فراهم کرده و در نتیجه ارزیابی عملکرد تصفیه خانه در حال بهره برداری و برنامه ریزی جهت بهبود روش بهره برداری میسر می گردد. پس از گردآوری نتایج آزمایشها، ضرایب مدلهای حذف آلاینده در دو محدودهMLSS برابر mg/l 3500-2500 وmg/l 4500-3500 در فصول گرم و سرد تعیین گردید. راندمان حذف اکسیژن خواهی شیمیایی، اکسیژن موردنیاز بیوشیمیایی و موادمعلق بترتیب برابر 4/0±86/94%، 65/0±3/97% و 48/1±71/94% بدست آمد و مدل مونود با ضریب بازده رشد(Y)، ضریب خودتخریبی(Kd)، نرخ حداکثر مصرف سوبسترا (K) و ثابت نیمه اشباع ((KS در دو محدوده MLSS بترتیب برابر mgCOD/mgSS 331/0-303/0، d-1030/0-033/0، d-183/1-657/1و mg/l 6/37-92/44 بعنوان منطبق ترین مدل حذف آلاینده با فاضلاب مورد مطالعه انتخاب گردید. پساب حاصل از تصفیه خانه مذکور از نظر دستیابی به پارامترهای کیفی فاضلاب برای مصارف کشاورزی و تخلیه به آبهای سطحی مطلوب می باشد و از ضرایب سینتیکی بدست آمده می توان درطراحی تصفیه خانه های آتی و بهره برداری سیستمهای موجود مشابه شرایط شهر تهران استفاده کرد.
    کلیدواژگان: مدلهای حذف آلاینده، مدل مونود، ضرایب سینتیکی، ارزیابی عملکرد، بهبود بهره برداری
  • علیرضا تقدیسیان، مصطفی تیزقدم غازانی* صفحات 65-76
    در این مطالعه، یک رآکتور ناپیوسته متوالی در مقیاس آزمایشگاهی با حجم کاری6.4 لیتر به منظور بررسی اثر شوری (سدیم کلرید) در محدوده 0-6.7% (گرم سدیم کلرید در لیتر فاضلاب)، برای تصفیه بیولوژیکی مورد استفاده قرار گرفته است. بنابراین، پارامترهای COD، MLSS، MLVSS و SVI اندازه گیری شدند. پارامترهای عملیاتی pH، اکسیژن محلول و دما، به ترتیب 7.5-8.5، mg/L 1.5-6.8 و 20-25 درجه سانتی گراد بوده است. COD فاضلاب سنتزی در حدود mg/L 650 ثابت نگه داشته شد. مدت زمان چرخه ی راکتور برای مراحل تغذیه، واکنش، ته نشینی و تخلیه ی پساب به ترتیب 1:20:1:1 ساعت بود. نتایج نشان داد که با افزایش غلظت نمک تا 6.7% سدیم کلرید، راندمان حذف مواد آلی از 94.22% به 53.69% کاهش یافت. علاوه بر این، MLSS 69% افزایش یافت، در حالی که MLVSS تقریبا ثابت ماند و SVI 83% افت پیدا کرد. نتایج نشان داد که استفاده همزمان از رشد معلق و چسپیده میکروارگانیزم ها و افزایش تدریجی شوری فاضلاب می تواند منجر به غلظت بیشتر بیومس و در نهایت افزایش راندمان حذف مواد آلی گردد. علاوه بر این، با توجه به نتایج عملکرد و سرعت ته نشینی با افزایش شوری به میزان قابل توجهی بهبود یافت.
    کلیدواژگان: رآکتور ناپیوسته متوالی، فاضلاب شور، رشد هیبرید، بیوفیلم، رشد معلق
  • مجید مداح*، عبدالنظام جعفری صفحات 77-86
    بخش حمل و نقل، یکی از منابع مهم آلودگی در سطح کشور است. طبق آمارهای موجود طی سال های1389 تا 1393، 61/23 درصد از انتشار دی اکسید کربن در ایران توسط بخش حمل و نقل ایجاد شده است. در این مقاله با کاربرد الگوی داده های تابلویی طی سال های 1389 تا 1393 عوامل موثر بر آلودگی ایجاد شده در بخش حمل و نقل استان های ایران مورد بررسی و تحلیل قرار می گیرد. نتایج حاصل از تخمین مدل نشان می دهد ارزش افزوده هر یک از بخش های اقتصادی کشور و تعداد وسایل نقلیه شماره گذاری شده دارای اثر مثبت و معنی داری بر آلودگی هستند. بر این اساس، یک درصد افزایش در ارزش افزوده سرانه در بخش های کشاورزی ، صنعت و معدن و خدمات به ترتیب باعث افزایش 11/0%، 08/0 % و 12/0 % در میزان تولید دی اکسید کربن استان ها در بخش حمل و نقل می شود. همچنین افزایش یک درصدی در تعداد وسایل نقلیه شماره گذاری شده نیز موجب افزایش 049/0 درصدی میزان انتشار دی اکسید کربن در بخش حمل و نقل استان ها شده است. با توجه به نتایج حاصله، پیشنهادات کاربردی نیز به منظور کاهش آلودگی هوای استانی ناشی از بخش حمل و نقل ارائه گردید.
    کلیدواژگان: حمل و نقل، آلودگی هوا، استان های ایران، الگوی داده های تابلوی، محیط زیست
  • زهره جابری، مسعود برادران*، مسعود یزدان پناه صفحات 87-98
    مشاهدات، تجزیه و تحلیل و پیش بینی های هواشناسی میتوانند به درک بهتر و افزایش مهارت در مدیریت عدم قطعیت وضعیت آب و هوا منجر می‏شوند و با افزایش بازده مصرف منابع و کمک به بهبود مدیریت تصمیم گیری برای جامعه سودمند باشند. با این حال بین تولید و اجرای پیش بینی‏های آب و هوایی شکافی وجود دارد و آن عدم استفاده عملی از پیش بینی های آب و هوایی در تصمیم گیری‏های کشاورزی می‏باشد. هدف از این پژوهش تبیین عوامل موثر بر تمایل به استفاده از اطلاعات زیست محیطی و هواشناسی توسط کشاورزان گندم‏کار شهرستان دهلران می‏باشد. برای این منظور از یک چارچوب ترکیبی متشکل از متغیرهای برجسته دو تئوری شناخت اجتماعی و پذیرش فناوری استفاده شده است. بر اساس جدول کرجسی و مورگان، نمونه آماری به حجم 350 نفر و با استفاده از روش نمونه‏گیری چند مرحله‏ای خوشه‏ای تصادفی متناسب با حجم جامعه آماری انتخاب شدند. معادلات مدل ساختاری نشان داد که در مدل پیشنهادی متغیر های انتظارات نتیجه، خودکارآمدی، سودمندی ادارک شده و درک سهولت استفاده قادرند 59 درصد از تغییرات تمایلات کشاورزان به استفاده از اطلاعات هواشناسی را تبیین کنند. نتیجه نشان می‏دهد این مدل پتانسیل پیش‏بینی کنندگی زیادی برای تمایل به استفاده از اطلاعات هواشناسی دارد.
    کلیدواژگان: اطلاعات هواشناسی، کشاورزان، تغییرات آب و هوایی، پیش بینی آب و هوا
  • مرضیه سادات میراحسنی، عبدالرسول سلمان ماهینی*، علیرضا سفیانیان، جهانگیر محمدی، رضا مدرس، رضا جعفری، سعید پورمنافی صفحات 99-114
    بررسی روند آینده تغییرات تراکم و سلامت پوشش گیاهی به کمک داده های سری زمانی مخصوصا در اکوسیستم های شکننده خشک و نیمه خشک می تواند اطلاعات مفیدی در زمینه اکولوژی و محیط شناسی ارایه دهد. ازآنجا که تصاویر ماهواره ای یکی از بهترین تصاویر سری زمانی هستند، بکارگیری آنها در مطالعات مذکور ثمربخش است. در تعیین روند داده های سری زمانی، استفاده از آزمون های آماری ضروری است، آزمون من-کندال یکی از این آزمون هاست. در پژوهش حاضر روند نوسانات پوشش گیاهی و پراکندگی مکانی آن در حوضه آبخیز گاوخونی طی سال های 2003 تا 2014 ارزیابی شد. در این راستا، 144 تصویر سری زمانی ماهانه شاخص NDVI MODIS در پایش منطقه ای پوشش گیاهی به کار رفت و روند تغییرات آن ها با استفاده از آزمون غیرپارامتری من-کندال تعیین گردید. در ادامه، الگوی روند تغییرات پوشش گیاهی شامل افزایشی، کاهشی و بدون تغییر در حوضه با استفاده از آزمون مذکور تعیین و پراکندگی مکانی آن ها ارائه شد. نتایج پژوهش نشان داد، روند کاهشی پوشش گیاهی در مناطق شمال، جنوب و غرب حوضه که دارای پتانسیل بالای تنوع گونه ای هستند و همچنین کشت آبی به وقوع پیوسته است. همچنین، طی سال های مطالعه زمین های شور و لخت در حوضه افزایش و زمین های کشاورزی به طور قابل توجهی کاهش یافته است. مقایسه نقشه روند حاصل با نقشه کاربری/پوشش منطقه نشان دهنده خطر وسیع در حوضه آبخیز گاوخونی است.
    کلیدواژگان: پایش پوشش گیاهی، MODIS-NDVI، تحلیل روند، آزمون من-کندال، گاوخونی
  • مینو علی خانی، محمد جواد نوری، محمود قلعه نویی* صفحات 115-132
    فضای سبز در شهرها، یکی از مهم ترین عوامل موثر بر کیفیت زندگی شهروندان می باشد تا حدی که از آن به عنوان یکی از شاخص های مهم توسعه یافتگی سکونتگاه ها یاد می شود. ضرورت ایجاد کاربری های جدید شهری برای پاسخگویی به نیازهای روزافزون شهرنشینان و نگاه سوداگرانه به محیط شهری در کنار عدم برنامه ریزی صحیح در زمینه مکان یابی و توسعه فضاهای سبز شهری به تدریج موجب کاهش سهم فضای سبز در میان کاربری های شهری شده است. هدف این مقاله ارائه روشی نوین جهت اولویت بندی نیاز به توسعه فضای سبز در مناطق شهری می باشد. بدین منظور مناطق پانزده گانه شهر اصفهان ازنقطه نظر نیازمندی مناطق به توسعه فضای سبز مورد ارزیابی و اولویت بندی قرارگرفته اند. در راستای نیل به هدف مقاله، ابتدا 18 متغیر محیطی که در مکان یابی فضاهای سبز شهری موثر هستند از ادبیات نظری موضوع استخراج و داده های مرتبط با این 18 متغیر از طریق اسناد و اطلاعات مختلف برای هر یک از 15 منطقه شهر اصفهان مهیا گردیده است. سپس با استفاده از مدل F’ANP شاخص مرکب "نیاز به توسعه فضای سبز" محاسبه شده و بر اساس آن اولویت بندی انجام شده است. نتایج به دست آمده نشان می دهد که مناطق 8 و 10 به ترتیب دارای بیشترین اولویت و منطقه 9 دارای کمترین اولویت جهت توسعه فضاهای سبز شهری می باشند.
    کلیدواژگان: اولویت بندی توسعه فضای سبز، معیارهای مکان یابی فضای سبز، مدل F’ANP، مناطق پانزده گانه شهر اصفهان
  • محمد کریمی فیروزجایی، نعیم میجانی، مجید کیاورز*، سید کاظم علوی پناه صفحات 133-153
    بررسی تاثیر گسترش فیزیکی شهر بر تغییرات طبقات دمایی و تاثیر حرارتی اراضی ساخته شده و غیر ساخته شده بر یکدیگر در بسیاری از مسایل محیط زیستی از جمله نگرانی های مربوط به مصرف انرژی، دغدغه برای ایجاد محیط های شهری با کیفیت تر و توسعه ی شهری پایدار کاربرد دارد. هدف از این پژوهش بررسی تاثیر گسترش فیزیکی شهر بر تغییرات طبقات دمایی و تاثیر حرارتی اراضی ساخته شده و غیرساخته شده بر یکدیگر می باشد. برای این منظور در این پژوهش از تصاویر چند زمانه لندست، محصول بخار آب مودیس و داده های زمینی شهر بابل و حومه آن برای تابستان سال های 1364، 1371، 1379، 1387 و 1394 استفاده شده است. برای طبقه بندی کاربری اراضی و محاسبه دمای سطح به ترتیب الگوریتم های بیشترین شباهت و تک کاناله بکار گرفته شده است. نتایج پژوهش نشان داد که دمای سطح اراضی فضای سبز و زراعی با کاهش فاصله از اراضی ساخته شده افزایش می یابد. اراضی ساخته شده بر روی دمای سطح اراضی اطراف خود تاثیر مستقیم گذاشته و اراضی غیرساخته شده واقع در طبقه دمایی بالاتر به نسبت طبقه دمایی پایین تر در میانگین فاصله نزدیکتر به اراضی ساخته شده قرار می گیرند. نتایج پژوهش نشان دهنده تاثیر حرارتی اراضی ساخته شده و غیر ساخته-شده بر یکدیگر تاثیر می باشد.
    کلیدواژگان: تغییرات، اراضی ساخته شده، اراضی غیر ساخته شده، تاثیر حرارتی، اثرات محیط زیستی
  • علیرضا میرزاخانی، سمانه ثابت قدم *، فرهنگ احمدی گیوی صفحات 155-169
    هواویزها ذرات جامد و مایع معلق در جو هستند که با تغییر خواص فیزیکی و تابشی ‌‌ابرها بر بودجه تابشی جو تاثیر می‌گذارند. عمق نوری هواویزها (AOD) و نمای آنگستروم (α) از مهم‌ترین ویژگی‌های هواویزها به‌شمار می‌روند. هدف از مقاله حاضر، مقایسه ویژگی‌های فیزیکی و نوری هواویزها در دو منطقه شهری تهران و مشهد برای دوره 4 ساله از 2010 تا 2013 است. برای رسیدن به این هدف، داده‌های سنجنده OMI برای تعیین و محاسبه نمایه‌های نوری هواویزها به‌کار رفته است. مقایسه توزیع بسامد فصلی AOD (500 nm) در تهران و مشهد بیانگر این است که در همه فصول مقدار AOD در تهران بیشتر از مشهد بوده و به‌طور کلی غلظت هواویزهای تهران بیشتر از مشهد است. در هر دو شهر، بیشترین مقدار AOD در فصل بهار و تابستان رخ می‌دهد. هم‌چنین کمترین مقدار AOD برای تهران و مشهد مربوط به فصل زمستان است. بررسی تغییرات روزانه α نیز نشان می‌دهد که مد غالب هواویزهای تهران مخلوطی از ذرات ریز و درشت و مد غالب هواویزهای مشهد از نوع ذرات ریز است. مقایسه توزیع بسامد فصلی α در تهران و مشهد حاکی از آن است که در هر فصل هواویزهای مشهد دارای ابعاد کمتر از هواویزهای غالب در تهران است
    کلیدواژگان: هواویزهای جو، نمای آنگستروم، عمق نوری هواویزها، ماهواره OMI
  • نگین بارشادت، حمیدرضا شعاعی، علیرضا رضوانی * صفحات 171-192
    چالش‌های پیش‌روی محیط‌زیست و تغییرات غیر قابل برگشت آن، ضرورت توجه به مسائل زیست‌محیطی را اجتناب‌ناپذیر کرده است. این امر موجب گردیده معماران در پی یافتن راهکارهای جدید جهت تامین محیط مطلوب انسان باشند. اگرچه فضاهای آموزشی سهم کمی از سرانه زمین‌های شهری را به خود اختصاص می‌دهند، لیکن نگرش به رویکردهای معماری پایدار در فضاهای آموزشی از جایگاه ویژه‌ای برخوردار است، چراکه ساخت‌و‌ساز مدارس سبز پاسخی است به بحران‌های زیست‌محیطی و آموزشی مضاعف به دانش‌آموزان در گرایش به آن .
    این پژوهش با هدف پیشنهاد مولفه‌ها و شاخص‌های طراحی پایداری محیطی مدارس ایران، به دنبال پاسخ به این سوال است که استانداردهای جهانی طراحی فضاهای آموزشی پایدار کدامند و دارای چه مولفه‌ها و شاخص‌هایی می‌باشند و چگونه می‌توان از آن‌ها در طراحی فضاهای آموزشی ایران استفاده نمود؟ روش تحقیق توصیفی- تحلیلی و ترکیبی از روش‌های زمینه‌یاب و تحلیل‌محتوا و مقایسه‌ای می‌باشد؛ همچنین روش گردآوری داده‌ها به صورت کتابخانه‌ای- اسنادی است. نتایج بررسی با ارائه جداول و نمودارهای تحلیلی نشان داد که از تلفیق دو سیستم LEED و BREEAM می‌توان سیستم جدیدی جهت طراحی فضاهای آموزشی پایدار ایران ارائه نمود که شامل 7 مولفه و 46 شاخص است که 19 شاخص تحت تاثیر عوامل محیطی قرار داشته، می‌بایست بومی‌سازی شوند.
    کلیدواژگان: فضاهای آموزشی، معماری پایدار، سیستم ارزیابی، مدارس سبز
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  • Masoud Shakarami *, Safar Maroufi Pages 1-16
    Introduction
    Due to its especial geographic condition, Iran, as a semi-arid country, suffers from water shortage for domestic, industrial and agricultural usages. As limited water supplies, the use of non-conventional water resources such as industrial or municipal wastewater, is common practice in many parts of the world including Iran. It is estimated that at least 20 million hectares in 50 countries are irrigated with raw or partially treated wastewater. Also it is estimated that potential volume of wastewater in urban and rural areas in Iran will be 4369 and 823 million m3, respectively. On the other, the application of sewage sludge in agricultural soils has been widespread in many countries around the world and also in Iran. The application of sewage sludge in agricultural has been shown to improve soils such as organic matter, nutrients, porosity, aggregate stability, bulk density and plant productivity. Despite the growing interest in wastewater and sewage sludge usage, excessive application of them may have some harmful effects such as human health problems, runoff and leaching of nutrients to surface and groundwater, undesirable chemical constituents, pathogens, accumulations of heavy metals in plants and soils, negative environmental and health impacts. So, wastewater and sewage sludge application should be under controlled conditions to minimize health risks of pollution to agricultural products, soil, ground and surface water. The use of medicinal plants and herbal medicines is increasing rapidly all over the world, which shows the importance of cultivation and production of these plants. One of the important needs of medicinal plants, in order to achieve high performance and quality, is plant nutritional needs. Therefore increasing in soil fertility, could be increased yield of medicinal plants. Medicinal plants today are cultivated commercially in polluted environments where soil, water and air contain rather high levels of pollutants. These plants appear to be a good choice for phytoremediation since these species are mainly grown for secondary products (essential oil) thus the contamination of the food chain with heavy metals is eliminated. Aromatic and medicinal plants also have a demonstrated ability to accumulate heavy metals. The mint (Mentha spicata) is a medicinal plants and it has received considerable economic importance due to the large demand for its essential oil in food, pharmaceutical, cosmetic and hygiene industries. The objective of this study was to determine the use of wastewater, sewage sludge on growth and nutrient concentrations of mint (Mentha spicata).
    Matherials and Methods
    This study was conducted at the greenhouse of Bu-Ali Sina University located in Hamedan, western Iran. The experiment was run in May 2015- February 2016), including 5 months for soil preparation (in lysimeters) and 5 months for crop cultivation and harvesting. To evaluate the use of wastewater and its sewage sludge on growth and nutrient concentration of mint (Mentha spicata), a factorial experiment based on completely randomized was designed with three replications in 27 lysimeters. The factors included three types of watering: tap water (W1), raw wastewater (W2) and treated wastewater (W3), three sewage sludge levels: 0 (S1), 50 (S2) and 100 tha-1 (S3) and three time of harvesting (T1, T2 and T3). Therefore, 9 treatments (W1S1 to W3S3) were considered for investigation. It is noted that the time of harvesting factor was not considered to be an independent factor. 27 volumetric lysimeters were applied as Cultivation beds (26 × 30 × 30 cm). The soil had two layers: the upper layer (0 to 50 cm) with sandy loam texture, and the bottom layer (50 to 110 cm) with sandy clay loam texture. After beds preparation, mint (Mentha spicata) was planted in them. The raw and treated wastewaters as well as sewage sludge were prepared from wastewater treatment plant of Hamedan. Also, municipal compost was prepared from Kermanshah Compost Company. Overall, 13 irrigation programs with 10-day intervals were applied. The plants shoot were harvested at the full flowering stage in 3 times. At the end of each harvesting stage, the fresh and dry weights, as well as the amount of N, P, K, Ni, Cd and Pb of mint were measured. Also after the last harvesting, soil samples were taken at two depth of lysimeter: D1: 10, D2: 40 and D3: 85 cm. Soil samples were analyzed for Ni, Pb, Cd, total N, total p and K.
    Discussion of Results
    The ANOVA test for effects of water quality and compost levels on fresh and dry weight as well as nutrient in mint showed that the amount of N, K, P and Cd were influenced by interaction between water quality and sewage sludge levels. But amount of Ni and Pb in shoot of mint was not influenced by interaction between water quality and sewage sludge levels. The results showed that using of wastewater and sewage sludge heavy metals in soil, so, compared to control, W2S3 were increases Pb, Ni and Cd in soil 304, 375 and 208 percent respectively. The heavy metals accumulated in soil surface layers (at depths of 10) and heavy metal concentrations and their ranges decreased with deepening of soil layer. had low vertical movement. Preferential flow and metal complexation with soluble organic apparently allow leaching of heavy metals. Also, the result showed that application of wastewater and sewage sludge increased fresh and dry weights of mint. As, in compartion control, W3S3 incresed fresh weight and dry weight of plant to 257 and 239 %, respectively. Also, performance of plant were increased during next harvesting. Many of researchers reported that providing balance nutrients and gradual nutrient release from organic sources during period of growth can be positive role in enhancing the growth of mint. The reasons for increasing the yield of plants include: Having the organic matter, increasing soil water holding capacity, strengthening the plant hormone-like activities, increasing nutrient uptake by plants and to generally improve the chemical and physical soil structure, noted. The amount of nitrogen in plant was varied among the treatments. The maximum (4.65 %) and minimum (1.11 % dry weight) amounts of nitrogen were observed in W2S3 and W1S1, respectively. Total N concentration in W2S3 was 3.12 times greater than that in W1C1. Also the highest amount of P (0.67 % dry weight) and K (3.85 mg in dry weight) was observed in W2S3. Also, the results indicate that using the wastewater (raw wastewater andtreated wastewater) and sewage sludge (50 and 100 tha-1), compared to the control (fresh water and soil without any sewaage), increas heavy metals (Ni, Pb and Cd) of mint. As, maximum and minimum of heavy metals concentration in the shoot of mint were obtained in W2 and W3 as well as in C3 and C1, respectively.The concentrations of heavy metals (mg kg-1 dry wt.) in mint ranged from 0.01 to 0.57 for Pb, 0.02 to 0.71 for Ni and 0.01 to 0.3 for Cd. The results of this study showed that the amount of heavy metals (Ni, Pb and CD), were lower than the international Cd standard level of FAO. The reasons for the increase in the amount of nitrogen, phosphorus and potassium in plant can be noted rich wastewater and sludge in elements.
    Conclusions
    In thudy, the effects of wastewater sewage sludge on nutrient concentrations and growth of mint (Mentha spicata) were studied.The results showed that the use of wastewater (raw and treated) and sewage sludge different levels of sludge, increased performance and uptake N, P, K, zinc, Pb, Ni and Cd in plant significantly. Although the concentration levels of Pb, Ni and Cd is lower than the limit of FAO standard, but long-term use of these wastes should be done cautiously.
    Keywords: Wastewater, sewage sludge, Mint, Growth parameters, Heavy metal
  • Samira Moradli, Abbas Khoshhal * Pages 17-33
    In this work, by constructing a sequencing batch reactor (SBR) and the use of microorganisms and microalgae Chlorella vulgaris, the performance of the system is studied for treating sanitary wastewater of Yazd power plant, Iran. For this purpose, the effect of pH, temperature, influent chemical oxygen demand (COD) concentration and airflow rate is examined on removing of COD and its residual concentration in wastewater. Another aspect of this research is the development of a multilayer feed-forward neural network model to predict the concentration of residual COD during the process of treatment. The pilot SBR reactor consisted of a wastewater storage tank, an aerobic tank and a settling tank and the used wastewater in this research was sanitary wastewater of Yazd power plant. Each cycle of the reactor was 8 hours including 5 min of filling, 450 min of aeration, 20 min of settling and 5 min of discharge. In order to supply the required microorganisms for the reactor setup, active sludge was prepared from the return line of the sludge of the Yazd power plant wastewater treatment plant. Also due to the quality of the microalgae of Chlorella vulgaris and its accessibility, this microalgae was prepared from the Yazd sewage stabilization pond and both of the microorganisms and microalgae were transferred to the reactor. At the beginning of the operation, the influent COD entered the system with 300 mg/l concentration (minimum organic load). 20 days after the initial setting up of the reactor, the removal efficiency reached its maximum, microorganisms, and microalgae adapted to the existing conditions. Then, at the cycle time of 8 hr the concentrations of residual COD were obtained at different pH, temperature, influent COD concentration and airflow rate. Sampling of the system was done at intervals of one hour for testing. In this study, a multilayer perceptron artificial neural network (MLP-ANN) was developed via employing Levenberg–Marquardt training algorithm in order to predict the concentration of residual COD. The ANN consisted of three layers, that is, only one hidden layer was used between the input and output layers. Input layer consisted of five neurons, which included pH, time, temperature, airflow rate, and influent COD concentration, and output layer had one neuron, which was residual COD concentration and the optimum number of hidden neurons was obtained by guessing and error. In order to increase the convergence and accuracy of the neural network, the input and output data were normalized and scaled to the range of 0–1. The performance of the ANN model was measured by root mean square error (RMSE) and correlation coefficient (R2) between the predicted values of the network and the experimental values. One of the important parameters that can have a significant effect on the performance of wastewater treatment is the amount of organic load in the influent wastewater. Increasing of the influent COD concentration, caused to increase the residual COD concentration in the wastewater. It was concluded that according to the destructive effect of increasing the influent COD concentration, control of the influent COD concentration in a constant range is necessary. This will cause the necessary substrate for the growth of microorganisms and microalgae to be provided consistently and sufficiently. The maximum influent COD concentration of the power plant was 1100 mg/l and at least 300 mg/l. Therefore, by establishing a return flow from the effluent wastewater of power plant to the primary wastewater storage tank and adjusting it to the influent COD concentration, the amount of fluctuations in the influent wastewater load was reduced and the influent COD concentration was fixed at 600 mg/l. One of the effective parameters on the performance of the wastewater treatment system is the pH of influent wastewater. After one hr of testing, the residual concentration of COD was approximately 53 mg/l. After this time, at first, the COD concentration increased at low pH, and even at pH of 4, it reached to 120 mg/l. The reason was that at the beginning of the treatment by microorganisms and microalgae, the digestion of wastewater organic materials was done. The result was the appearance of organic acids that caused the further decrease of pH, thereby reducing the activity of microorganisms and microalgae and increasing of COD concentration. Then, by decomposition of the produced acids and the beginning of the decomposition of proteins and fats, the pH of the system, the activity of microorganisms and microalgae increased and the COD concentration decreased and fixed at about 60 mg/l. At high pH, because of the high activity of microorganisms and microalgae, observed that the residual COD reduction process performed with a suitable gradient during the time and eventually remained constant. As shown in Fig. 1b, the most suitable pH for the activity of microorganisms and microalgae is pH of 8, in which case the residual COD concentration has reached the lowest value of 34 mg/l. Temperature is one of the important effective parameters on activity of microorganisms. The best temperature for system operation is between 30-35 °C. At high temperatures, because of the reduced solubility of air in the wastewater, enough oxygen and CO2 were not provided for microorganisms and microalgae, which caused to increase the residual COD concentration, compared to the other temperatures. On the other hand, at low temperatures due to the reduced growth of microorganisms and microalgae, increase of residual COD concentration occurred. According to available data from the power plant, the temperature of influent wastewater was almost 30 oC in most seasons. On the other hand, according to Fig. 1c, there is no significant difference between the concentration of residual COD at 30 oC and 35 oC, so the optimum temperature of this process was chosen 30 oC. In aerobic treatment systems, desirable aeration should be done to create suitable conditions for the growth of microorganisms. Increasing of the aeration generally had a positive effect on the performance of treatment process and with increasing aeration, residual COD concentration has decreased. However, this effect is not noticeable for airflow rate of more than 50 l/min. More aeration will increase the costs, sometimes lead to cell failure, and thus decrease the growth of microorganism and microalgae. Therefore, in this study, the optimum airflow rate of 50 l/min was selected. In this airflow rate, the lowest residual COD concentration was obtained. In this study, 208 laboratory data was used for modeling. Two thirds of the data were randomly selected for training the network and one third remained for evaluation of modeling accuracy. To determine the optimum number of neurons in hidden layer, 1 to 15 neurons were used. The transfer functions of hidden and output layers were selected tangent sigmoid (tansig) and linear (purelin) respectively. The results indicated that the network with the number of neurons equal to seven had the best performances because the root mean square error (RMSE) had the lowest value and the correlation coefficient (R2) had the closest value to one. In this study, at first, a pilot SBR reactor was installed and operated by microorganisms and microalgae Chlorella vulgaris. In the next stage, the system was evaluated with variables such as pH, temperature, influent COD concentration and airflow rate. By analyzing the values obtained from the reactor, optimum values of these parameters were determined to achieve the lowest residual COD concentration. The results showed that at a pH of 8, temperature of 30 °C, influent COD concentration of 600 mg/l and airflow rate of 50 l/min, concentration of residual COD was obtained 34 mg/l, which indicates an increase in efficiency of the system. In addition, an artificial neural network model was developed to predict the concentration of residual COD. ANN predicted results were in good agreement with the experimental data with a correlation coefficient and root mean square error of 0.944 and 0.034 respectively.
    Keywords: Wastewater Treatment, Sequencing batch reactor (SBR), Microalgae Chlorella vulgaris, Modeling, Artificial neural network
  • Maliheh Dashti, Gholamreza Dehghan *, Alireza Kataee Pages 35-45
    Physiological and biochemical parameters in macroalgae Chara sp. in response to oxidative stress following remediation of malachite green
    Introduction
    The effluents of wastewater in some industries such as dyestuff, textiles, leather, paper, plastics, etc., contain various kinds of synthetic dyestuffs. The effluents of these industries are highly colored and the evacuation of these wastes into receiving waters causes intense damages to the environment and biological systems. In recent years a number of studies have focused on some micro/macro-organisms that are able to biodegrade and absorb dyes in wastewaters. Phytoremediation is a newly evolving field of science and technology that uses plants and algae to clean up polluted sites. This technology has been received attention lately as an innovative, cost-effective alternative to the more conventional water treatment methods.
    In this study, macroalgae Chara sp. was used in order to decolorize a dye solution containing Malachite Green (MG). MG, a triarylmethane dye, is most widely used for coloring purposes such as dyeing silk, leather, wool and paper in textile industries. In addition, it is extensively used in the aquaculture industries as a biocide worldwide. Induction of oxidative stress and the related formation of reactive oxygen species (ROS) are frequent results of environmental stressors. The main purpose of the present investigation was to evaluate the potential of Chara sp. in remediation of MG, the study of changes in some physiological and biochemical parameters, including photosynthetic pigments content, phenolic compounds and the activity of some major antioxidant enzymes including peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) that can be involved in algae resistance to dye and/or its metabolism.
    Materials and Methods
    2.1. Algal biomass and dye removal
    The algal species was acquired from Azna-lake (Khalkhal) in North of Iran. The algal species was washed with distilled water to remove macro/microscopic contaminations. According to its morphology and macro/microscopic observations, it was identified as Chara species belongs to Charophyta.
    The decolorization experiments were carried out with different initial dye concentrations (7.5, 15 mg/L), pH values; (5.5–8.5), temperature; 25 °C and experiment time; 1-8 h. Treatments were carried out at 25 °C and pH = 8, and concentrations of 0, 7.5 and 15 ppm. Analysis of metabolites and enzyme assays were performed following two hours of treatment of algae with MG.
    2.2. Enzyme activity assays
    The algae was subjected to 7.5 and 10 mg/L MG in the nutrient solution for 2 h to investigate the effect
    of the dye on antioxidant enzyme activity compared with a control. The algae biomass was homogenized in 0.1 M phosphate buffer solution (pH 7) containing 1% polyvinylpyrrolidone. The homogenate was centrifuged at 2000g at 4 °C for 20 min. The supernatant was used as the crude extract for enzyme activity and protein content assays.
    Superoxide dismutase (SOD, EC 1.15.1.1) activity was assayed by measuring its ability to inhibit the photochemical reduction of nitroblue tetrazolium (NBT). Peroxidase (POD, EC 1.11.1.7) activity was measured by spectrophotometry. Catalase (CAT, E.C. 1.11.1.6) activity was measured spectrophotometrically by following the dismutation of H2O2 at 240 nm for 3 min and calculated using extinction coefficient 39.4 M-1.cm-1.
    2.3. Non-enzymatic assays
    Plant photosynthetic pigments (chlorophyll a and b and total carotenoids) were measured spectrometrically at 470, 662, and 645 nm, respectively, using equations described by Lichtenthaler (1987) after extraction from leaves with 100% acetone. Malondialdehyd (MDA), as a marker of lipid peroxidation and oxidative stress, was estimated by measuring the thiobarbituric acid-reactive substances (TBARS). TBARS were determined from the solution absorbance at 532 nm.
    Total phenolic compounds were determined using Folin-Ciocalteau reagent. The absorbance was measured at 720 nm by spectrophotometer. Flavonoid contents were measured by the aluminum chloride. Colorimetric assay as described previously. After 5 minutes absorbance of the solution read at 507 nm.
    Results and discussion
    After 2 h exposure of algae with 7.5 and 15 mg/L of MG, the content of photosynthetic pigments was determined. According to the results, the observed chlorophyll a (Chl a), chlorophyll b (Chl b) and the total chlorophyll content was decreased to 18.3% after 2 h exposure (P>0.05). Carotenoid content was signif icantly (P<0.05) increased (48%) compared with control group after exposure with 7.5 and 15 ppm of MG. These results showed that the increased level of carotenoids characterized by the antioxidant properties in response to dyestuffs is probably the part of the strategy adopted by Chara sp. to counteract the toxic effect of free radicals generated under oxidative stress. Chlorophyll content decreased may be due to the formation of proteolytic enzymes such as chlorophyllase which is responsible for the chlorophyll degradation and damaging the photosynthetic apparatus.
    During bioremediation of MG, the levels of MDA increased in the presence nonsignificantly. Oxidative stress initiates lipid peroxidation of cell membrane polyunsaturated fatty acids.
    Total phenol compounds were increased in algae by increasing the concentration of dye matter (P <0.05). The amount of flavonoids was increased significantly in accordance with the increase of MG concentration (P <0.05). Flavonoids were increased by two or three times as much as the concentration of dye matter compared to the control group. Total phenols play a significant role in the regulation of plant and algae metabolic processes and overall plant growth. It has been shown in some studies that synthesis of polyphenols depends on abiotic factors.
    Enzymatic analysis

    During phytoremediation processes, different plant enzymes (especially oxidoreductases) act on specific
    recalcitrant pollutants to remove them by precipitation or transformation to other products. SOD neutralizes reactive superoxide radicals to hydrogen peroxide, which is detoxified by other antioxidative enzymes such as CAT and POD. After 2 h exposure to 7.5 and 15 ppm of MG, a signif-icant induction in the activity of SOD was observed in Chara sp., also the total SOD activity in the Chara significantly increased with increasing the MG concentration compared to the control. SOD is one of the ubiquitous enzymes in aerobic organisms and plays a key role in cellular defense mechanisms against ROS. Its activity modulates the relative amounts of O2.- and H2O2 and decreases the risk of OH-˙ radical formation. POD activity showed a similar pattern to the SOD activity, at high concentrations of MG, POD activity was increased up to 44% (compared to the control) (P < 0.05). Increased POD activity at high concentrations of MG after the increment of SOD activity probably reflects the high demand for detoxification of produced H2O2. The activity of CAT was also decreased in the presence of 7.5 and 15 ppm of MG. After 2 h exposure the activity of CAT was decreased 32% compared with control (P>0.05). In the present work, CAT activity was signif icantly decreased by MG. Therefore, this enzyme did not appear to be an eff icient scavenger of H2O2 produced during treatment of MG. The decline in CAT activity might be due to inhibition of enzyme synthesis or a change in the assembly of enzyme subunits in the presence of MG.
    Conclusion
    In the present study, the activity of antioxidant enzymes and other markers of oxidative stress and metabolites in Chara sp. were measured during the bioremediation of malachite green by macroalgae. The activity of peroxidase and superoxide dismutase was significantly increased, while the activity of other main antioxidant enzyme, catalase was declined. Concentration of malondialdehyde, as a final product of lipid peroxidation, doesn't changed significantly during the remediation process. On the other hand, the amount of photosynthetic pigments (chlorophyl a and b) was decreased, and phenolic compounds was significantly increased with increasing MG concentration. These data indicated that induction of oxidative stress during remediation of MG by Chara sp. affects the activity of antioxidant enzymes and some of the secondary metabolites in macroalgae. Finally, macroalgae Chara sp. increases antioxidant enzymes and non-enzyme metabolites to achieve hemostasis during bioremediation process.
    Keywords: Macroalgae Chara sp, Synthetic dyes, Reactive Oxygen Species, antioxidant enzymes
  • Mina Rafati, Hossein Ghadamian, Ali Jalilzadeh, Azarmidokht Hossein Nia Pages 47-63
    Performance Evaluation and Biokinetic Coefficients Determination of Oxidation-Ditch Process using pollutant elimination models on Tehran South Wastewater Treatment Plant Keywords: pollutant elimination models , Monod model, Kinetic Coefficients, Performance Evaluation, Improved Operation Introduction Kinetic models are widely used in fundamental research of biodegradation processes to examine the hypotheses, to control and predict the operation performance in practice and to optimize the reactor design. In this work, different mathematical models including First-order substrate removal model, Grau second-order substrate removal model, Stover-Kincannon model and Monod model were conducted to investigate the reaction kinetics of the oxidation ditch reactor and kinetic coefficients were determined. The aim of this study was to evaluate different mathematical models for describing the COD removal kinetics in the oxidation ditch reactor and to compare the applicability of different models. Because of Monod model is one of the most popular models for various reactors and waste water treatments and commonly employ to describe the biodegradation kinetics, only a few studies succeeded in applying the other models to the oxidation ditch reactor. Thus, in order to determination of the biokinetic coefficients of sewage in south region of Tehran, four kinetic models were used to simulate biomass growth in the oxidation ditch reactor and were compared together, and so the best of them has been innovated to be used in design of Tehran wastewater treatment plants and then the performance of the treatment plant is evaluated and planned to improve the operation method. Methods & materials This cross-sectional study implemented in Tehran South wastewater treatment plant using Oxidation-Ditch(O.D) process. In this study 80 samples from the influent wastewater, reactor and effluent were collected periodically and experimented by the Standard Methods. The wastewater quality parameters including BOD5, COD, TSS and MLSS were measured in warm and cold seasons. These systems were operated under two different MLSS concentrations in the aeration tank. then four kinetic models were applied to simulate biomass growth in the oxidation ditch reactor. the kinetic coefficient in each model obtained as below: Removal efficiency and bio-kinetic coefficients in suitable model were also calculated. First-order substrate removal model Assuming the first-order substrate removal model was prevailing in the Oxidation ditch reactor, the substrate removal rate is expressed as Eq. 1. dS/dt=-k_l S (1) Where dS/dt is the substrate removal rate (g/L/d), k1 is first-order substrate removal rate constant (1/d), S is the substrate concentration in a reactor (g/L). In athe Oxidation ditch reactor, mass balance under pseudo-steady-state is expressed as follows Eq. 2 or 3 by introduction of the Eq. 2. Q/V (S_0-S)=-K_l S (2) ((S_0-S))/θ_H =-K_l S (3) Where Q is the inflow rate (L/d), V is the effective volume of the reactor (L), S0 is the substrate concentration in influent (g/L), and ƟH is HRT (d). The value of k1 is obtained from the slope of the approximate curve by plotting (S0 _ S) / ƟH against S. Grau second-order substrate removal model The common equation of a second-order model is given as follows: -dS/dt=K_S X(S/S0)^2 (4) Where kS is Grau second-order substrate removal rate constant (g substrate/g MLVSS/d), and X is the biomass concentration in a reactor (g MLVSS/L).The following Eq. 5 is obtained via integration of Eq. 4 within the boundary conditions of S=S0 and t=o to ƟH, X=constant, and linearization, (S_0 Ɵ_H)/(S_0-S)=Ɵ_H+S_0/(K_S X) (5) Where ƟH is HRT. As (S0 _ S) /S0 can be expressed as substrate removal efficiency and S0/kSX is a constant, Eq. 5 is modified as follows: θ_H/E=m+nθ_H (6) Where m is S0/kSX and n is a constant, E is substrate removal efficiency. The values of m, n and kS are easily derived by plotting ƟH /E against ƟH. Stover-Kincannon model The Stover-Kincannon model considers the substrate removal rate as a function of substrate loading rate at steady state. The general equation of Stover-Kincannon model is described as follows (7); dS/dt=(Q(S_o-S))/V (7) On the other hand, dS/dt is defined as follows in this model. dS/dt=(U_max ((QS_0)/V))/(K_B+QS_0/V) (8) Therefore, Eq. 7 is converted to the following equation. V/(Q(S_0-S))=(K_B.V)/(U_max QS_0 )+1/U_max (9) Where is the substrate removal rate (g/L/d), Umax and KB are the maximal substrate removal rate and saturation rate constant, respectively (g/L/d). The values of Umax and KB are obtained from the slope of the approximate curve by plotting V/Q (S0 _ S) against V/QS0. Monod model Yield Coefficient value (Y), the decay coefficient value (Kd), the kinetic constant (K) and saturation constant value (Ks) can be obtained according to Monod model. The substrate removal rate is represented as follows: r_su=(μ_m XS)/(Y(K_S+S)) (10) r_g=-Yr_su-K_d X (11) 1/SRT=YU-K_d=(Y(S_0-S))/θX-K_d (12) Where Y is the Yield Coefficient (mg COD/mgSS), and Kd is the decay coefficient value (1/d), The values of Y and Kd are obtained by plotting U against 1/SRT. θX/(S_0-S)=1/U=K_s/K.1/S+1/K (13) Where Ks is the saturation concentration (g/L), and K is the maximal specific substrate removal rate constant (g /d). The values of Ks and K are obtained by plotting 1/U against 1/S. Conclusion& Discussion of Result Plotting results are depicted in figures 1 to 4 Figure1 : First-order substrate removal model Figure 2: Grau second-order substrate removal model Figure 3: Stover-Kincannon model Figure 4: Monod model the regression line for the plotted linear equation of the model had a R2 of 0.84-0.87which was bigger than that found for three other models with R2 of 0.36-0.81. Removal efficiency and bio-kinetic coefficients in suitable model were also calculated. Monod model provided predictions having the most important relationship with factual data received from the study. In addition, Monod model turned out to be applicable to predict the biomass concentration in the oxidation ditch reactor. The solutions of kinetic studies obtained in this field will provide an invaluable tool in 'the design and process control of the oxidation ditch reactor.
    Keywords: pollutant elimination models, Monod model, Kinetic Coefficients, Performance Evaluation, Improved Operation
  • Alireza Taghdisian, Mostafa Tizghadam Ghazani* Pages 65-76
    Significant rise in concentration of saline wastewater entering the treatment plants has been resulting in many problems in the biological treatment processes. On the other hand, the specific conditions of physicochemical treatment methods for saline and hyper saline wastewater have limited their application on a large-scale. Over the past few decades, Sequencing Batch Reactor (SBR) process has been widely used as an efficient, well-designed and practical approach for treatment of domestic and industrial wastewater due to its cost-effectiveness and simplicity. In this study, a lab-scale Hybrid Sequencing Batch Reactor (HSBR) was used to examine the effect of salinity (NaCl), increased from 0-6.7% (g NaCl/ L wastewater), on the biological treatment. The Pilot-scale Plexiglas HSBR system with circular cross section was used for this study had a working volume of 6.4 L with dimension of 18 cm for diameter and 30 cm for its height. Polyethylene moving carriers with an average specific surface area of 500 m2/m3 and density of 95 kg/m³ were used as media for attached growth of biofilm. Two identical peristaltic pumps and three analogue time switches (Theben Germany) were used for controlling influent and effluent wastewater. The HSBR was operated in 24 h working cycle including 1 h influent feeding, 20 h reaction (aeration) time, 1 h settling and 1 h decanting. The activated sludge seeds were obtained from Shahid Beheshti University (SBU) municipal wastewater treatment plant located in north of Tehran (Iran). System was introduced by 3250 mg/L of MLSS as the start-up seed. The dissolved oxygen (DO) concentration, pH and Temperature in the system were maintained between 2.6-6.8 mg/L, 7.2-8 and 18-26 °C respectively throughout the study. COD, MLSS, MLVSS and SVI parameters have been measured over a period of 7 months operation. Results indicated that by increasing salt concentration from 0 to 67.7 g NaCl/L, the COD removal efficiency reduced from 94.22% to 53.69%. The adverse inhabitation effect of salinity causes significant decrease in COD removal efficiency. At 5 gNaCl/L, COD removal rate was increased to 94.22% which was the highest removal efficiency observed in this study. The reason for this little improvement was stimulatory effect of salt on activity of microorganisms. This finding that a small amount of salt (below 10 gNaCl/L) is in favor of bacterial growth and reproduction is in line with other studies. At the last salinity level of 67.7 gNaCl/L, after about 30 days to achieve the steady state conditions, the COD removal efficiency dropped at the rate of 41.76% compared to the highest efficiency at 5 gNaCl/L. The high concentration of salt causes loss of cellular activities, dehydration and inhabitation of many active enzymes in biological treatment. However, system showed a good performance for removal of organic matters compared to conventional SBR system even at 30 gNaCl/L (82.36%). The results of this study show that the removal efficiency of organic pollutant was inhibited less severely than those reported at equal levels of salinity. This might be result from the diversity of biological treatment process, variety of microorganism in biomass and influent wastewater. Moreover, it could be attributed to the biofilm special 3D-structure and capabilities for growth and reproduction of many kind of bacteria. Attached growth of microorganisms has a lot of distinct advantages over suspended growth. First, it could stimulate multi-cultural bacterial growth and consequently causes high active biomass. Second, biofilm unique structure could improve the interaction of substrate with microorganisms by proving a multiple reaction site. Third, as suggested by other articles, some protective substance like organic polymer which secreted by microorganism and acted as a defense mechanism in harsh environment, could grow more easily in biofilm than suspended sludge, and therefore salinity has more significant inhabitation on suspended sludge compared to biofilm MLSS and MLVSS were measured to represent the mass of microbes that exist in bioreactor. MLSS values were slightly increased with increase of salinity to 20 gNaCl/L. by increasing salinity further to 67.7 gNaCl/L, MLSS reached to its highest level at 10,530 mg/L. it means that MLSS increased about 69% from the beginning of the study. By increasing salinity, various kinds of species started to suppressed and as a result, the number of dead cells increased at higher rate compared to non-saline environment. On the other hand, slat-resistant microorganisms like halotolerant and halophilic species, have a chance to grow more favorably. As a result, the total amount of these specific organic matters increased with increase of salinity. It was also seen that MLVSS was increased to 3240 mg/L at the second stage of salinity corresponding to 5 gNaCl/L, and then had a relatively constant values until the end of experiments at 67.7 gNaCl/L salinity. This is suggested that regardless of total mass of microbes whether live cells or dead cells, viable and active cells are remained constant. As mentioned before, some specific salt-resistant microorganisms which were not dominant species at first, could grow and survived in high saline environment and therefore the amount of viable biomass remained unchanged. In this study, sludge settling performance was improved by increasing salinity. By increasing salinity from 0-67 gNaCl/L the SVI decreased from 156 mL/g to 27 mL/g and this result showed the improvement of sludge settling property with increase of salinity. In addition, sludge settling velocity was increased. By increasing salinity from 5 to 67.7 gNaCl/L, the differences in settled sludge at 10, 20 and 30-minute of SVI experiment became less and less, meaning that the suspended sludge was settled faster. Some factors could cause this better performance in settling property including a) inhabitation of filamentous bacteria in saline condition which led to better settling conditions b) selection of denser sludge which caused by combination of electrostatic and hydrophobic interactions and consequently reduction of repulsive force between particles c) with salinity activated sludge flocs become smaller and closer d) washout of lighter sludge flocs.
    Keywords: Hybrid Sequencing Batch Reactor, Saline Wastewater, Hybrid Growth, biofilm, suspended growth
  • Majid Maddah *, Abdolnezam Jafari Pages 77-86
    Introduction
    The geographical and climatic characteristics of Iran in utilizing transport infrastructure requires special attention to the issue of environmental pollution and greenhouse gases emitted by conventional transportation activities and, if necessary, specific measures to control pollution Air created in this section. Considering the significant contribution of transportation pollution in total contamination and taking into account the social costs resulting from it, as well as considering the negative effects of pollution on economic growth, health expenditure of households and the health of citizens and the high linkage of sector activities Transportation with activities of other sectors, investigation and research on the factors affecting the amount of pollution in this part is important and necessary. The service sector provides a demand-driven demand for many of the products of society that play a significant role in gross domestic product formation, such as mineral products, commercial and tourism activities. Given the direct effect of the transport sector's activities on the environment and air pollution, the development of other economic sectors could increase environmental pollution. According to the statistical reports in the energy charts published by the Ministry of Energy over the years, carbon dioxide gas has been the largest contributor to pollutant and greenhouse emissions in Iran during the study period. The share of carbon dioxide emissions in the transport sector (including road, air, sea and rail), compared with other sectors, including household, commercial and public sectors, agriculture, refineries and power plants, during the same period The average was 23.61%. Despite the various studies carried out in the field of air pollution, no study has ever been done on the factors affecting pollution in the provincial transport sector in Iran.
    Matherials & Methods
    In the literature of the research, the panel data model (combination of time series and cross-sectional data) is used to investigate the effect of factors affecting transportation pollution in the provinces of the country. Among the information research variables, carbon dioxide emissions are not available in the province, but according to published statistics on the rate of use of fuel and oil products of the provinces in the annual energy balance sheets and based on the standard announced by the inter-agency State of Climate Change (IPCC) In 2013, carbon dioxide emissions in the transport sector were calculated for provinces around the country between 2010 and 2015. Other data are also extracted from library resources.
    Discussion of Results
    Regarding the use of logarithmic data at the model's estimation stage, estimation coefficients are interpreted as the elasticity of pollution in the transportation sector relative to each of the explanatory variables. Accordingly, during the reviewed period, the interconnection between production in the economic sectors and the transport sector is confirmed. In fact, with the increase in production, transportation services are expanding, in this context, the lack of proper and standard facilities in the transport sector will lead to further pollution. According to the research results, an increase of 1% in the number of numbered vehicles also resulted in an increase of 0.49% in carbon dioxide emissions in the transport sector of the provinces on average. This finding confirms the role of polluting vehicles that are often produced internally. Comparison of the estimated elasticity marks indicates that the pull of the pollution per capita value added service is more than its elasticity over other sectors. This result seems to be due to the greater share of the service sector's activities in creating the value added of the entire country and the significant difference in this share in relation to the value added of other sectors. Also, a one percent increase in carbon dioxide emissions with a one-year lag in the transport sector has had a positive and significant effect of 0.8% on carbon dioxide emissions in the transport sector this year during the period under review.
    Conclusions
    In this paper, the effect of factors affecting pollution in the transportation sector of the country using provincial statistics in the framework of an econometric model of data panel during the period of 2015-2010 was investigated and the results of which, while conforming to theoretical foundations, with the result of other Studies in this area are also aligned. The results of the research showed that the number of numbered vehicles, the per capita value added of services, which includes transportation activities, added value of agricultural and industrial and mining sectors had a positive and significant effect on There are contaminants created in the transportation sector of the country's provinces. The positive effect of vehicles on transport pollution indicates the contamination of vehicles used by citizens, and the positive and significant effect of economic value added on transport pollution contributes to the direct relationship between production and pollution, which is the finding corresponds to the first region of the Kuznets curve. In fact, it can be said that the increase of provincial production, although increasing provincial income facilities and causing economic growth and development, but social costs increase the pollution of the economy of the provinces, which this problem It can reduce social welfare while introducing environmental damages. Accordingly, it is necessary to address the policy of decreasing air pollution through tools such as improving production efficiency, observing the standards required in the production of various economic sectors, and accurate monitoring of the state on the activities of enterprises and the stopping of the firm's activity Contaminating and violating environmental regulations should be considered by provincial authorities. At the end, there are also suggestions for reducing pollution of the provincial air.
    Keywords: Transportation, Air pollution, Iranian Provinces, Panel Data Model, environment
  • Zohreh Jaberi, Masoud Baradaran *, Masoud Yazdanpanah Pages 87-98
    Introduction
    Climate change is a topical subject worldwide and there is evidence that this phenomenon is taking place. Agriculture is one of the sectors most affected by climate change and Due to smallholder farmers heavy reliance on rainfed agriculture, climate change will increase vulnerability of the rural populations due to food and nutrition insecurity. Climate change is expected to affect agriculture in different ways and to a different extent in different parts of the world and in different agro-ecosystems. In particular, Communities in most developing countries have been identified as being the most vulnerable to climate change because of multiple stressors and reduced adaptive capacity. Adaptation is one of the policy options for reducing the negative impact of climate change in agriculture sector. A wide variety of adaptation options has been proposed as having the potential to reduce vulnerability of agricultural systems to risks related to climate change. In this regard, Climate information and forecast can be of value when used in decisions involving risks posed by adverse weather or climate. In fact, Climate information is an important pre-requisite for informed decision-making in risk management and adaptation that would help prevent climate extremes from becoming disasters and threats to livelihoods. Climate forecast have shown potential for improving adaptation of agriculture to climate shocks, but uncertainty remains about whether farmers would use such information in crop management decisions. Despite tremendous efforts to improve weather and climate predictions and to inform farmers about the use of such weather products, farmers’ intention toward forecast use remain poor and farmer use of forecasts has not increased. Because very little is known about the motivations underlying farmer decisions to use or not to use weather and climate forecasts, we designed and conducted a survey based on the combining social cognitive theory and Technology Acceptance Model to gather such information from farmers in Dehloran, Iran. The Technology Acceptance Model is a frequently used behavioral model for predicting and explaining Information Technology usage. A key purpose of TAM is to provide a basis for tracing the impact of external variables on internal beliefs, attitudes, and intentions. The TAM identifies two two most important factors namely perceived ease of use and perceived usefulness. To date the TAM has been used to address why users accept or reject information technology. This model is an adaptation of the theory of reasoned action proposed by Fishbein and Ajzen to explain and predict the behaviours of people in a specific situation. Social cognitive theory (SCT) also is a theoretical framework for analyzing human motivation. The Social cognitive theory consists of factors influencing behavior intention. We used environment factors, Perception of others’ behavior, outcom expentency and self-efficacy as variables of Social cognitive theory in our integrated model. Hence, in our integrated model two factor of perceived ease of use and perceived usefulness were considered as independent factors, Perception of others’ behavior, outcome expediency, self-efficacy and environment factors as mediated and intention to use or not to use weather and climate forecasts as dependent factor. Methodology In this paper, we address the questions of whether smallholder farmers in Dehloran would intend to use climate forecasts in making crop management decisions and whether such use would lead to benefits. A structural equation model was developed to explore relationships between factors affecting intention to use Climate information and forecast. The study was designed as a cross-sectional survey. Target population of this study consisted of 3820 wheat growers. Using a multistage stratified random sampling method, 350 farmers were selected for this study. The sample size was determined using the Morgan table. Data were collected based on a questionnaire structured to assess the components of combining model. We use a self-report questionnaire to examine the proposed research model empirically. A self-report method refers to an approach in which observation data are provided by participants instead of raters or coders. The questionnaires data were gathered based on a face-to-face survey of farmers. The respondents were assured about anonymity and confidentiality. They were also given the right to refuse participation and also to refuse to answer any question they deemed to be too sensitive or that they felt uncomfortable about. Those declining participation were replaced by other students. No payment was made to the respondents. Answering time for the questionnaire was about 15-20 min. The survey was pre-tested and piloted on 30 farmers from outside the study area. Cronbach alpha reliability coefficients were calculated for the pilot study and used to refine the questions for the final questionnaire. All scales indicated good-to-excellent reliability, generally 0.76–0.89. Results Regarding demographic variables, the participants were aged from 22 to 85 and had a mean age of 44.59 years (SD = 14.24). in main analysis, Structural equation modeling (SEM) was used to assess the causal relationships that were hypothesized in the proposed model. the results of structural equation modeling obtained for the proposed conceptual model revealed that χ2 /d.f. = 1.98 (p < 0.001), GFI = 0.83, RMSEA = 0.053, NFI = 0.79, RFI = 0.78, and CFI = 0.88. Accordingly, the summary of the overall goodness-of-fit indices indicated good fit of the model and data. (χ2 /d.f. value was less than the recommended threshold value 5, RMSEA value was less than the recommended threshold value 0.08). The finding indicates that technological Acceptance Model factors (perceived ease of use and perceived usefulness) significantly positively affect the social cognitive theory factors (self-efficacy, outcome expectancy and Perception of others’ behaviour). Path relationships revealed that outcome expectancy (β = 0.58, p < 0.001) and self-efficacy (β = 0.26, p < 0.001) had a positive direct relationship with intention to use meteorological information. In addition Perceived ease of use has direct effect on perceived usefulness (β = 0.74, p < 0.001), self efficacy (β = 0.80, p < 0.001) and outcome expectancy (β = 0.27, p < 0.001). perceived usefulness also has direct effect on Perception of others’ behavior. However, environment factors and Perception of others’ behaviour affected intention nonsignificantly. Findings suggest that respondents’ self-efficacy help predict whether an individual intends to use weather and climate information. Regarding indirect effect, perceived usefulness and perceived usefulness had a strong indirect effect on intention. The model accounted for 59% of variance in intention to use Climate information and forecast. Also, The finding indicates that in suggenstion model environment factors (beta= 0.01, p>0.05) and Perception of others’ behaviour (beta= 0.56, p>0.05) were not significant predictors of intention to use climate forecast.
    Conclusion
    To successfully transfer costly weather and climate products into meaningful information that farmers can use in their decisions, farmers must understand the products and have the intention and motivation to extract the relevant pieces of information and apply them to specific decision contexts. This study integrated two sociopsychological theories, social cognitive theory, with a widely used information system technology acceptance model (i.e., the TAM) to provide a comprehensive behavioral model for understanding elderly farmers intention toward using meteorological information. The framework was extended from the original TAM by considering the relationships among technological factors (perceived ease of use and perceived usefulness), and social cognitive factors (system self-efficacy, environment factors and Perception of others’ behavior, outcom expentency), and behavioral intention to use the meteorological information. regarding the samples, the integrated model fitted considerably well. The proposed model has been proven to be valuable for evaluating and predicting the behavioral intention of climate information and forecast because it provides an integrative perspective that prompts researchers and practitioners to pay attention to the interdependence of these aspects. This study is a justification for using the constructs of this model in politics and decision making that encourages farmers to use meteorological information. The proposed integrative congnitive-technological model may serve as a theoretical basis for future research and can offer empirical foresight to practitioners and researchers in the agricultural departments and rural communities.
    Keywords: meteorological information, farmers, climate change, weather forecast
  • Marzieh Sadat Mirahsani, Abdolrassoul Salman Mahiny *, Alireza Soffianian, Jahangir Mohamadi, Reza Modarres, Reza Modares, Saeid Pourmanafi Pages 99-114
    Introduction
    Investigation of the future trend of changes in the density and health of the vegetation due to climate and land use/land cover changes can be useful in ecological and environmental studies using time series data especially in dry and semiarid brittle ecosystems. Time series analysis is a powerful tool for investigating the trends of natural phenomena in the past and present. The Satellite Time Series provides the most appropriate data for analysing the trend of changes in natural and human phenomena and predicting for the future. A time series is the collection of statistical data collected at regular intervals. Determining the trend (increasing, decreasing and unchanged) of the vegetation can be one of the ways to help manage vegetation monitoring. In this regard, the use of statistical tests to determine the trend of time series data is essential. There are different methods for determining the process, which are divided into two sets of parametric and nonparametric methods. Since satellite imagery is one of the best time series illustrations, the use of these data in trend studies is fruitful. Vegetation indices are used to monitor and evaluate vegetation dynamics using satellite imagery. NDVI is the most famous useful in plant monitoring. The NDVI, is used as a useful indicator of photosynthesis capacity identification, usually used to examine environmental and ecological changes. Therefore, remote sensing through the NDVI satellite index can measure surface vegetation changes due to the strong correlation between the vegetation and this index. The NDVI is also reliable for identifying vegetation stress because, as a result of degradation of vegetation in the land, vegetation characteristics such as health, density are majorly changed Materials and methods Monthly MODIS NDVI times series images from the MOD13A3 series, were collected from the site of NASA from 2003 to 2014 (144 images). Then the images from Gavkhuni basin have been extracted to determine the trend of vegetation changes. Mann-Kendall test was presented based on the significance of the Tau Kendall correlation coefficient (τ) and then developed. Correlation coefficient measures the relationship between two series of variables to determine if the first variable increases with increasing the second variable, or decreases or the patterns of change are not relate together. This method is widely used to handle time series. In general, Mann-Kendall statistical test can be used to determine the uniform trends of ubnormal distribution data based on the ranking. Given that the Mann-Kendall test, in addition to the trend, also specifies the type of trend occurring, this model does not require the input of normal data. In the test, for time series data trends, positive values indicating incremental trends and negative Z values represent decreasing trends. Results Vegetation fluctuations of mean monthly MODIS NDVI time series images of Gavkhoni basin from 2003 to 2014 were presented. The maximum vegetation cover is observed in spring months. This increase reached its maximum during the course of the study in 2007, and then reached its maximum four months later and then sharply declined in 2008. In 2009, vegetation cover in Gavkhuni basin is relatively modest. In fallowing, the fluctuations are almost the same, but declined sharply in 2014. In addition, the highest vegetation density is observed in the western and central regions of Gavkhuni basin. Also, this figure shows that vegetation density is high in 2003-2006 and has declined significantly by 2014. Accordingly, the vegetation cover increased in January 2003 through January, a dramatic drop in February, a slight decrease in March to May, a modest increase in June to July, a slight increase in the months of July to September, in October And November has been a slight decrease, and December has seen an increase in vegetation. The trend of long-term vegetation changes in Gavkhuni basin based on 144 images of the monthly MODIS-NDVIwere implemented in the Idrisi Tersset software. At first 144 time series images were converted into TSF file format. The resulting trend map indicates that the vegetation trend is incremental with a value of τ equal to 0.68 to a decreasing trend with the value of τ equal to -0.65. Accordingly, the trend of increasing vegetation is more dispersed in the north-eastern and central to west parts of the basin, and slightly to the south of Gavkhuni basin. In addition, the largest decline in vegetation occurs in the central regions of the east and south of Gavkhuni basin. This trend is evident in the northern and western basins as well as in the south of the basin. In addition, decreasing trend of vegetation is more concentrated in areas of basin which referring to the use/land cover map are aquaculture. This trend indicates a sharp decrease in the rain-fed agriculture. Referring to the land use/land cover map, the vegetation cover of the Gavkhuni wetland during the study period has also been subject to decreasing or unchanged trend. The vegetation of the rocky areas of the north-east of the basin has also increased marginally. Accordingly, the most extensive areas indicates unchanged trend of vegetation in Gavkhuni basin.
    Discussion & Conclusions
    The results showed that the largest decline in vegetation was observed in 2007, when the catchment area was faced with drought at this time. Also, the annual average vegetation map in 2014 with the least amount of vegetation density has been encountered. Due to the fluctuation of vegetation, the need for serious attention of planners is required because it can be said that vegetation as the representative of environmental health also reflects the characteristics effective biophysics in growth, such as adequate water, undiluted and nutritious soil, etc., provide both the protection of wildlife and soil conservation against erosion. Also, since vegetation cover has declined from 2003 to 2014 in the months of April and May (when is the beginning of the growth season in the Gavkhuni basin), it indicates a crisis in agriculture in the Gavkhuni basin. The regional variations of vegetation in Gavkhuni basin from 2003 to 2014 through the time series images of MODIS NDVI was determined using non-parametric Mann-Kendall Tau and contextual tests, and areas with increasing, decreasing and unchanged vegetation cover were determined. The results showed that the extent of the vegetation variation trend as well as the extent of the decreasing trend in the Contextual Mann-Kendall method was more than Tau Mann-Kendall, and the trend in most of the area remained unchanged, which only indicates whether vegetation is present in this area or not. This case is achievable by comparing the trend map with land use / land cover map in 2014 or following years. In addition, it was revealed that the decreasing trend with the sever vegetation decline has occurred in the central regions of the Gavkhuni basin and along the Zayandehrud River and also in the urban areas, which can indicate the high urban growth and land use /land cover change from the vegetation to the construction site in this basin. Accordingly, a sharp decreasing trend was observed in the northern and western regions as well as in the south of the basin, which with referring to the land use /land cover maps and type /vegetation maps, these areas are highest proportion of rangeland vegetation and fertile farming along the Zayanderroud River. These lands affected by land cover/land use and have been severely subjected to land degradation due to the dryness of Zayandehrud Rive in recent years. This urged urgent measures to prevent land degradation. In addition, since the highest reduction in temporal monitoring in the Gavkhuni basin has been observed in the months of April to June, and these months are growth season and cultivation in the Gavkhuni basin, this necessitates a serious actions to mitigate the risks. Also, the study of vegetation trends showed that during the study years, saline lands in the Gavkhuni basin increased and the agricultural land was significantly reduced.
    Keywords: Vegetation Monitoring, MODIS-NDVI, Trend Analysis, Mann-Kendal test, Gavkhuni
  • Minoo Alikhani, Mohammadjavad Nouri, Mahmoud GHALEHNOEE * Pages 115-132
    These days profitable development and the need to create new urban land uses to ask needs of urban residents has gradually declined and these located in the incorrect place. It causes, the distribution of green spaces in the city was often inappropriate and social injustice is created. The purpose of this paper is to evaluate the 15 regions of the Isfahan municipality in order to determine regions which have priority for the development of urban green space. Isfahan is one of the metropolises in Iran that has many environmental problems such as drought and water crisis, lack of proper urban land for developing of green space, air pollution, increasing population and vehicles and etc. So a systematic planning in the field of optimum locating for green spaces is very necessary. This paper looking for answering this question: What is the priority of creating green spaces in 15 regions of Isfahan? So at first 18 parameters which are effective in the construction of green spaces have been determined. Based on the data available of these parameters in the 15 regions, F’ANP model has been used in order to build composite index and evaluate regions.Isfahan, with an area of over 550 square kilometers and a population of more than two million, is the third metropolis in the center of Iran. Service range of this city consists of 15 regions which this paper has been studied separately. Any prioritization requires the selection of indicators and criteria which related to that category. The importance of each of these indicators is indicated with considering the weight for each indicator. Among the effective indicators choosing the right place (which was discussed in the theoretical foundations), indicators which are compatible with conditions of Isfahan, were selected and studied in the 15 regions.
    In the first step, 18 key indicators have been extracted from theoretical literature. In the second step these indicators according to documents and information available are calculated in the 15 regions and required data have been provided in order to analyze indices. In the third step obtained data are considered as model’s inputs. The reason for using this method is that it covers one of the most important methodological problems in the field of location and prioritization. Previous studies show that prioritizations have so far been according to the subjective methods. In order word weight of influencing parameters have been done by experts and researchers.
    Mentality of the parameters' weight are resolved by F’ANP model. In fact, the Isfahan’s environment determines parameters' weight and how to prioritize by determining relationships between parameters. This paper is in the category of applied research and it’s methodology is analytical-descriptive.
    In this model, the adequacy of the sample size which be evaluated by test Sphere s’Bartlett and Kaiser- Meyer- Olkin (KMO) is more important than the amount of the sample size. So as long as if the values of these two tests do not reach the standard level, the sample size should increase or communalities should change. In this paper with regards to limitations of checked options (15 regions), suitable amount of these tests is obtained by reducing the number of variables. Therefore, 8 parameters deleted in order to increase the accuracy of the model. Then the factors are named according to the gender and nature of the indicators (Table1). After removing some indicators, the amount of KMO and Bartlett’s test are arrived to the standard value (Table2). These values show that the accuracy of the model is acceptable.
    At the end of the research, composite index of need for green space development is calculated. So achieved weights are multiplied by the values of each indicators. The result of this operation shows values of indicators. The following formula has been used in order to build composite index:〖NGSD 〗_i=∑_(j=1)^J▒〖W_(F^' ANP j) QV_ij 〗
    In this formula 〖NGSD〗_i is composite index of need for green space development which belongs to region i. ، W_(F^' ANP j) is the relative weight of indicator j which is obtained from F’ANP model as output. And QV_ij is the amount of score indicator j in region i.
    Then 15 regions of Esfahan have been prioritized by achieved composite index. These scores mean that the each region which is weaker in each indicator, it’s score is lower too. In fact less score indicates the more critical in existing green space in the region. So that region should be located at the higher priority of developing of green space.
    Green space in the city is one of the most important indicators which affects the quality of life. With the growing urbanization, green spaces have been damaged by city managers for supplying other needs of citizens or by Land traders. So these days choosing the right priority of the development of green spaces and right place to create green space is more important than the past. So we can say this is one of the most important managerial needs in the modern cities. So far, many studies have been done in theoretical literature on urban planning and the environment. Lack of systematic approach which is far from the minds of experts is one of the most important gaps in this theoretical literature. The purpose of this article is to provide a method which is based on a systematic approach.
    For this purpose, 18 parameters which explain how to prioritize the development of green spaces have been evaluated using the F'ANP model.
    The results indicate that three factors of "physical and functional needs", "natural and environmental needs" and "economic and social needs" explain the priority of the need to develop green space in Isfahan.
    The findings show that regions of 8 and 10 placed in the top priority and region of 9 placed in the least priority. The results of this research have been checked with reports of the need to develop green space which is done in the municipality of Isfahan that results confirm the prioritization of this model.
    This indicates that we can achieve valuable results in terms of prioritization by applying a systematic approach to this issue and by using systematic multivariate methods of evaluation.
    Keywords: Prioritization of green space development, Location criterions of green space, F'ANP model, 15 regions of Isfahan
  • Mohammad Karimi Firozjaei, Naeim Mijani, Majid Kiavarz *, Seyed Kazem Alavipanah Pages 133-153
    Introduction
    In the last decades, the earth’s surface has experienced various changes due to some obscure reason being caused by human activities consisting of deforestation and cities expansion. These widespread human changes pose several adverse problems. For instance, an environmental qualitative decrease which culminates in the reduction of living quality is the result of these adverse changes. Warming of the urban environment owing to oblivious effects of unstable urban expansion, replacing of natural land cover with urbanization phenomena, inter alia, pavements, buildings, concrete and other urban constructions, are discerned as the main factors of creating heat island, which cause the vanishing of land surface cooling effects. Moreover, skyscrapers and narrow streets diminish the airflow and give rise to an increase in the environment temperature. The remote sensing images are known as an appropriate information source for preparing heat maps and also benefiting from widespread applications for the precise investigation of climate changes and urban and non-urban land use changes, due to the continuous and extensive coverage, timeliness and the ability to acquire information in the reflective and thermal range of electromagnetic waves. The population of Babol city steadily increase as a result of population growth and villagers’ emigration and bring about excessive and unplanned constructions, alteration in the physical model of the city and finally expansion of the city in various directions. Physical expansion leads to numerous changes in urban land use and suburbs agricultural uses. Consequently, several serious problems occur including adversity in uses, the urban environment disorder as well as the vanishing of suburbs agricultural lands and their land use change into urban uses (residential, industrial and etc.). One of the adverse effects of urban physical expansion, declining of green space and changing of agricultural land use into the urban land use is the rise in the surface temperature. The aim of this study was to investigate the effects of Babol city expansion on changes in temperature classes and the thermal effects of built-up and non-built-up lands on each other during the period of 1985-2015.
    Materials & Methods
    For this purpose, multi-temporal Landsat images were used in this study. For calculating the land surface temperature, ingle channel algorithm were used, and Maximum likelihood algorithm was also applied to classify images. Therefore, land use changes and land surface temperatures (LST) were examined, and thereby the relationship between land-use changes was analyzed with the land surface temperature. Surface temperature changes map for the period of 1985-2015 was prepared and analyzed regarding land use changes map for the study area to investigate the effects of land use changes on surface temperatures changes. By using the mean and standard deviation of normalized thermal images, the area was divided into three thermal classes. The status of each land use in the specified thermal classes and the impact of surface temperature in built-up and non-built-up lands on each other were investigated.
    Results & Discussion
    The results indicate that most land use changes in the studied area belong to the change of agricultural and green space uses into built-up use in suburbs, which are 740.52 and 472.14 hectares, respectively. As it was shown through the findings, 92% rise was observed for the built-up use area. These changes are more significant in the periphery of the city. The use of green space has risen from 1656.55 hectares in 1985 to 2036.52 hectares in 2015, which shows an increase of 23 percent. The trend of growing the use of green space on the periphery of the city is clearly characterized by the conversion of agricultural land to citrus gardens. The growth of the use of green space is less than the growth rate of built-up use. The built-up use has experienced a significant growth trend over the study period, as area of built-up use has risen from 19% in 1985 to 52.52% of the area in the studied area in 2015. The results of the LST mean survey of land use types for the study area show that the built-up lands than the other lands have the highest LST for all years. Water lands have the lowest LST owing to the high water heat capacity. In most of the years, arable land has a lower LST mean than green space land, which is mainly due to the high moisture of the arable land and the greater activity of evapotranspiration. Most changes in surface temperature of the area are related to the distance of 0-800 meters of built-up area. The main reason could be the conversion of the agricultural and green space lands into the built-up lands in the area. The most prevalent temperature class in all years is the medium temperature class which covers the suburb lands. The hot temperature class is more highlighted in the center of the city, streets and ways out of the city. Although the adjacent of the city is covered by medium temperature class, cold temperature class are located far from the built-up urban area. Cold temperature class which follows a decreasing trend, is related to lands which are far away from the city. Also, hot temperature class at which the area increases annually, is adjacent to the city core and exit ways of the town. The highest temperature changes belong to areas which transformed from the other uses into built-up use during the past 30 years. Due to human activities which produce heat, the area which has remained in the form of built-up land use during this time period has had a noticeable temperature rise. Green space and agricultural areas which have not transformed into other land uses benefit from the least temperature changes during this time period. On account of growing of built-up land use, an increase has occurred in the area of hot temperature classes and a decrease in the area of cold temperature categories. Built-up lands have direct effect on their adjacent land surface temperature. The results of the survey with regard to arable lands and green space in different temperature classes indicate that the areas of green space and arable lands, located above the upper temperature, are proportional to areas of the land that are located in lower temperature classes and they are located in the average distance closer to the built-up lands. In other words, the green space and arable lands that are located closer to the built-up lands have higher temperature relative to the green space and arable lands which are far from the built-up lands. Also, green space lands which are located in urban environments have a higher temperature in proportion to the area of the green space lands adjacent the city owing to the high temperature of their surrounding areas. Green space lands in the urban environment, which have no high area, are more affected and classified into hot temperature classes. Built-up lands, which are located in the urban environment and adjacent to the green space, also has a lower average surface temperature than the green space, and sometimes located in the middle temperature class. This refers to the effect of moderating surface temperatures in built-up lands by green space lands.
    Conclusions
    As a result, non-built-up lands with higher temperature classes are in a lower average distance from built-up lands compared to those with lower temperature classes. Built-up lands in the adjacent agricultural and green space lands have lower surface temperature compared to other built-up lands. As a result, these lands are considered to be medium temperature class. The results of this study showed the importance of planning and management for preserving agricultural and green space lands and preventing them from being transformed into built-up lands which increases the surface temperature and negative environmental impacts.
    Keywords: Changes, built-up lands, non-built-up lands, thermal effects, environmental effects
  • alireza mirzakhani, samaneh sabetghadam *, Farhang Ahmadi Givi Pages 155-169
    Atmospheric aerosols, including solid and liquid particles suspended in the atmosphere, are a mixture of particles in the air, of different sizes, shapes, compositions, and chemical, physical, and thermodynamic properties. They affect the earth’s radiative budget and climate directly by absorbing and scattering the radiation, and indirectly by acting as cloud condensation nuclei. Aerosols have both direct and indirect effects on the climate by scattering and absorbing solar and terrestrial radiation as well as modifying the distribution of clouds and their radiative properties. They have been concerned in health effects and visibility reduction mostly in urban and regional areas. Aerosol types which contribute to the scattering include organic particles, water-soluble inorganic species and dust. In urban areas, the principle particle species that absorbs radiation is black carbon, that is produced from incomplete combustion processes mainly from diesel engines. Natural aerosols are generally larger in size than the secondary aerosols produced from gaseous precursors and combustion, and their chemical composition depends on their sources. However, aerosols produced from natural and antropogenic sources are mixed together and thereby each aerosol particle is a composite of different chemical constituents. Atmospheric aerosol optical and physical properties are two of the major uncertainties in global climate change which are also responsible for many impressive atmospheric effects. Therefore, retrieval of the aerosol optical parameters is an important issue for the atmospheric research communities. Investigations of aerosol characteristics and their optical properties will lead to a better understanding of both the regional and local behavior of aerosols over a region. Aerosol optical indices such as aerosols optical depth, Angstrom exponent, single scaterring albedo, asymmetry parameter are the most important characteristics of aerosols that are influenced by the physical properties and concentration of particles. These properties also play an important role in the Earth’s climate and radiation budget. Aerosols optical depth is a key factor to measure the degree of atmospheric pollution and to study the climate response to aerosol radiative forcing. Its value shows the aerosol density, while Angstrom exponent is an intensive parameter that depends on the aerosol size distribution and increases with decreasing particle size. In other words, Angstrom exponent is the slope of the logarithm of aerosol optical depth versus the logarithm of wavelength. It is commonly used to characterize the wavelength dependence of aerosols optical depth and provides some nformation on the aerosols size distribution. When scattering is dominated by fine particles, Angstrom exponent has large values(i.e., around 2); it approaches to 0 when scattering is dominated by coarse particles. Remote sensing of aerosols from satellite-based sensors turn into an important instrument to monitor and quantify the aerosol optical properties over the globe. Study of aerosol optical properties provides a detailed knowledge of both the regional and local behavior of aerosols as well as their influence on the Earth’s climate, radiative forcing, visibility and photochemistry. Although considerable development has been taken in understanding aerosol properties, they are poorly quantified because of the lack of adequate information on temporal and spatial variability of aerosols. In this paper, using the satellite data from the Ozone Monitoring Instrument (OMI) aerosols optical depth and Angstrom exponent are investigated over two megacities in Iran, Tehran and Mashhad, during the period from January 2010 to December 2013. OMI was launched in July 2004 on NASA’s EOS-Aura satellite, also part of the A-train constellation. The reasons of choosing these urban areas are mainly the existence of a large number of populations and substantial sources of emissions from natural and anthropogenic emissions. Previous studies show that the increasing emissions of aerosols during the past decades in these two area have affected their local climate. Here daily, monthly and seasonal variations of aerosol properties in terms of optical depth and Angstrom exponent are analyzed to provide a detailed insight into the variation of aerosols loading and their possible causes. Results concerning the seasonal frequency distribution of aerosols optical depth (AOD) at 500 nm indicate that values of this index in Tehran are higher than Mashhad in all seasons. It shows the existence of higher aerosol density causing the higher atmospheric turbidity over Tehran than Mashhad. During the study period, the daily amount of AOD over Tehran is ranged from 0.2 to 1.6, while over Mashhad the daily AOD is ranged from 0.1 to 0.9. High values of aerosol optical depth are obtained during the spring and summer seasons, respectively, and low values are seen during the winter in the both cities. There are also significant variations of Angstrom exponent over the two cities. Based on the results, the dominant mode of aerosols over Tehran is a mixture of fine and coarse particles, but fine particles are dominant over Mashhad. Therefore, it can be deduced that turbidity in Tehran is subject to a complex mixture of aerosol types, including anthropogenic aerosols and dust, while anthropogenic aerosols are dominant over Mashhad. To further understand the seasonal variations of aerosols, AOD was studied at different wavelengths. Results show the seasonal dependency of AOD values that are mainly related to various emission sources. In order to investigate the origins of aerosols and transports of the air masses toward the understudy regions, back trajectory analyses based on the NOAA HYSPLIT (National Oceanic and Atmospheric Administration Hybrid Single Particle Langrangian Integrated Trajectory) model, was performed. For six days, as the representatives of polluted and clean days, air mass back trajectories were computed using HYSPLIT model. Results indicate the existence of different patterns of particles transport over the two cities. It is seen that the sources of aerosols over Tehran are both from local emissions and from the long range dust transport, while aerosols over Mashhad are more likely from local sources.
    Keywords: aerosols, aerosols optical depth, Angstrom exponent, OMI
  • Negin Bareshadat, Hamidreza Shoaei, Alireza Rezvani * Pages 171-192
    Sustainability has become one of the major concerns of development over the past few years. The emergence of several environmental crises has created many problems for governments and forced them to identify effective factors and frameworks. Construction has also been one of the most important factors that affect environment. This has led architects seek new solutions to provide a desirable human environment. Although educational spaces account for less urban land per capita than other uses, the move towards the establishment of sustainable schools is a tangible way of achieving the goals of sustainable development and the development of environmental culture. Sustainable and green construction of schools can encourage and educate students more effectively since students spend about half of their time in schools and can develop these approaches in the future, both in individual and family behavior and in their careers. Hence, this strategy can be more effective with environmental education in harmoniously constructed spaces. Finally, another aspect of the importance of creating and paying attention to green schools is a new approach to establish schools in the natural environment, which is on the agenda of many developed countries. Therefore, paying particular attention to the sustainable design of schools and the creation of appropriate environmental conditions should be the main factor in physical development. The need to address this issue has led many studies to take place in advanced countries. Researchers have introduced several criteria for assessing sustainable schools, which also have a logical convergence. These criteria have been introduced as "Green School Assessment Systems" in different countries. The study of green school assessment systems in the world and a review of existing documents and practices in Iran suggest that, despite the efforts made, it is unfortunate that there is no system for the design, operation and evaluation of sustainable schools. Also, sustainability components and indicators of these schools have not been formulated based on cultural, social and economic conditions. This has led to the fact that, despite the importance of constructing green schools in the leading countries, Iran has given more attention to environmental education. In these small number of schools that are currently active as green schools, individual education has been emphasized. The existence of a comprehensive Environmental Charter (2015) and the stated objectives also confirm this issue. Therefore, the issue of identifying the components and criteria of architectural design of sustainable schools in Iran is one of the topics that although the necessity of addressing it is clear to everyone, but no serious action has been taken so far. Accordingly, the purpose of this study is to propose components and indicators of environmental sustainability design in schools in Iran, seeking to answer the questions of what are the global standards of designing sustainable educational spaces, what are their components and indicators, and how they can be used in designing educational spaces in Iran? The research method is descriptive-analytical and a combination of field, content analysis, and comparison is applied. Data collection method is library-documentary. Accordingly, in order to do theoretical studies, we investigate the research background, similar studies in the world and Iran. Having reviewed the research literature, some accounts of sustainable schools and their characteristics are presented. It is concluded that green schools are schools come up with better learning environments for learners, as well as savings in resources and spending. Besides encompassing different aspects of sustainability, the schools themselves are means of sustainable education. The advantages of designing such schools are financial, environmental, and human. In these schools, environmental education is carried out both through individual (human) education and education via the environment. Given the broad scope of the present research, education via the environment was in the spotlight. In the next phase, the research conducted on the most valid systems of green building evaluations was reviewed. .The studies conducted, the review of the performance of the most important and valid evaluation systems of green buildings in the world and proposed evaluation systems for green educational spaces and their comparison with each other led to the identification and introduction of the most valid evaluation systems of green educational spaces. These systems include LEED, BREEAM, CASBEE, and DGNB. Following the introduction of the foregoing systems, their components, indicators, as well as scoring method were presented. Next, an analogy was made between the four systems in accordance with four parameters of their effect, evaluation process, scoring criteria, the least score obtained and criteria categorization. Eventually, scoring systems of LEED and BREEAM were the most valid international systems in terms of evaluation of green educational spaces. In order to determine the convergence and difference of LEED and BREEAM evaluation systems, their components and indicators were compared with each other. The results of comparing the components and indicators of the two selected systems led to 7 component and 46 indices. Considering their importance, they can be used as components and indicators affecting environmental sustainability of educational spaces in Iran. Considering that some of the components and indicators proposed are under the local and climatic conditions of the region or country and should be made localized, the indicators can be categorized into three broad categories:1. Indicators that are not affected by local and climatic factors and are applicable and evaluated in all countries according to international standards; 2. Indicators that should be determined for each individual country under the effect of local and climatic factors and then used in the assessment; 3. Indicators that are sub-components of innovation in design and, depending on the designer's point of view, can provide solutions for improving environmental quality and energy efficiency. Since the present study focuses on the components and indicators of environmental sustainability of educational spaces, suggestions regarding the localization of indicators under the climatic conditions are presented. Since Iran has different climatic zones, attention to the climatic conditions of the area can have a significant impact on the sustainable design of the building. The most important affective climatic factors can be temperature, precipitation, humidity, wind, and amount of sunlight. To determine how these components affect the environmental sustainability indicators, depending on the area in question, meteorology stations’ data and related analysis can be used. In addition, the impact of factors such as: latitude, distances and proximity to the sea level, vegetation cover and soil type, etc., should also be considered on the components and indicators. On the other hand, the impact of climatic conditions on educational spaces is different due to differences in the type of operation and the time of use in comparison to other uses. In these spaces, the time or pattern of occupation and density in the space, which are considered as the main features of the educational spaces, are different from ordinary spaces. These places also have a significant internal load, which affects the thermal needs of space. Therefore, in order to create optimal conditions for the quality of the indoor environment as well as saving resources, it is recommended that as other countries use International Building Codes (IBC), AIA, USGBC,… for localization, Iran should also use publications approved by the country's management and planning organizations and the renovation, development and equipping of schools, which is provided for educational spaces as well as standards for housing and urban planning, the country's engineering organization, the environmental protection agency, and all organizations that are somehow involved in the construction and conservation of resources. Due to the fact that some of the cases have not been addressed in the approved circulars and magazines or have been paid less, reference materials can be used. In this way, the items proposed in foreign regulations and rules are compared with similar cases in Iran and domestic items are used depending on local conditions.
    Keywords: Educational spaces, Sustainable architecture, Evaluation system, Green schools