- پیاپی 25 (زمستان 1396)
- تاریخ انتشار: 1396/12/25
- تعداد عناوین: 7
صفحات 1-17با توجه به افزایش روزافزون احداث بناها، جاده ها، راه آهن و غیره در مناطق کوهستانی و پرشیب، لزوم پایدارسازی شیب های طبیعی و مصنوعی بیش از بیش مورد توجه قرار گرفته است. روش های متعددی به منظور پایدارسازی شیب ها وجود دارد که در تمامی آنها هدف، افزایش نیروهای مقاوم در برابر نیروهای محرک و در نتیجه افزایش ضریب اطمینان است. هدف ازپژوهش حاضر، محاسبه پایداری دامنه های لغزشی مشرف به جاده و نقش میخ کوبی و تراس بندی در پایدارسازی این دامنه ها در 40 کیلومتری ابتدای آزادراهخرم آباد - پل زال است. در این پژوهش، ابتدا هشت دامنه لغزشی مشرف به جاده مشخص شد، سپس تمامی پارامترهای مدل تحلیل پایداری شیب که شامل: cs: چسبندگی خاک، cr: چسبندگی ریشه، φ: زاویه اصطکاک داخلی خاک، γd: چگالی خاک و γw: چگالی مرطوب خاک است. با مطالعات میدانی، نمونه برداری از خاک و تجزیه و تحلیل توپوگرافی دامنه ها استخراج و برای تعیین ضریب پایداری دامنه ها، این پارامترها در نرم افزار تحلیل پایداری شیب وارد و میزان ضریب ایمنی برای هر دامنه مشخص شد. نتایج پژوهش نشان داد کهاحداث جاده و انجام عملیاتخاک برداری، سبب قطع جریان رواناب وجریانات زیرسطحی دامنه ها شده و این جریاناتبه صورت رواناب در سطح دامنه خاک برداری وروی جاده جاری شده و سبب ناپایداری شیبدامنه های خاک برداری می شود؛ همچنین با استفاده از این مدل می توان دامنه های ناپایدار را شناسایی و نوع عملیات حفاظتی را برای افزایش ضریب پایداری مشخص کرد؛ به طوری که عملیات میخ کوبی در دامنه شماره 6 با کلاس آسیب پذیری خیلی زیاد، با موقعیت جغرافیایی «43''20 °33عرض شمالی و »59''10 °48طول شرقی باعث افزایش ضریب پایداری از مقدار 57/0 به 98/1 و عملیات تراس بندی بر روی این دامنه باعث افزایش ضریب پایداری به مقدار 10/2 شد که در نهایت، می توان مناسبت ترین و بهترین روش را برای انجام عملیات حفاظتی مشخص کرد.کلیدواژگان: ضریب ایمنی، میخ کوبی، تراس بندی، زمین لغزش، آزادراه خرم آباد، پل زال
صفحات 19-34محیط زیست و توسعه، دو موضوع اساسی از نگرانی های جهان هستند. تاثیرپذیری محیط زیست از فعالیت های انسان و افزایش تقاضا در استفاده از منابع، امری است که پژوهشگران را بر آن می دارد تا مناطق آسیب پذیر را شناسایی کرده و در صورت لزوم، اقدام لازم در راستای مدیریت و حفاظت محیط زیست و توسعه پایدار تبیین گردد. در این راستا، شاخص آسیب پذیری محیط زیستی استان لرستان با مشخصه هایی از شرایط طبیعی (توپوگرافی، اقلیم، زمین شناسی، شاخص نرمال پوشش گیاهی و تراکم آبراهه)، محیطی (کاربری سرزمین، شاخص آسیب پذیری دراستیک و فرسایش پذیری) و انسانی (تراکم جاده، تراکم جمعیت و محل انباشت زباله های شهری) ارزیابی شد. به این منظور، از دو فرایند تحلیل سلسله مراتبی و ترکیب خطی وزنی استفاده شد. نقشه های شاخص آسیب پذیری محیط زیست حاصل از دو روش یادشده، در 5 طبقه آسیب پذیری خیلی کم، کم، متوسط، زیاد و شدید طبقه بندی شدند. بر پایه نتایج حاصل از روش تحلیل سلسله مراتبی، 76/1% استان با مساحت 1/482 کیلومتر مربع در طبقه آسیب پذیری شدید قرار گرفت؛ همچنین، بر پایه نتایج حاصل از روش ترکیب خطی وزنی، 18/14% با مساحت 4/3998 کیلومتر مربع در طبقه آسیب پذیری شدید قرار گرفت.لکه های داغ در سطح استان، شامل مرکز و جنوب شهرستان الشتر، مرکز و شرق شهرستان خرم آباد، مرکز و شرق شهرستان بروجرد، مرکز دورود، شمال و شرق الیگودرز و شمال ازنا هستند. در شهرستان های کوهدشت، رومشکان و دوره به صورت پراکنده و در غرب شهرستان پلدختر و شمال غرب و جنوب غرب نورآباد، به عنوان لکه داغ شناخته شدند. در نهایت، اولویت آسیب پذیری منابع آب های سطحی و زیرزمینی، پوشش گیاهی و خاک در سطح استان مشخص شد.کلیدواژگان: شاخص آسیب پذیری محیط زیست، لکه داغ، تحلیل سلسله مراتبی، ترکیب خطی وزنی، سیستم اطلاعات جغرافیایی، استان لرستان
بررسی اثر ویژگی های مورفومتری در پراکنش سطوح واریزه ای (مطالعه موردی: ناهمواری آتشگاه در جنوب شهرستان پاوه، استان کرمانشاه)صفحات 35-51واریزه ها شواهدی از رفتار سنگ ها در مقابل نوسانات دما و رطوبت هستند. تغییرپذیری مکانی سطوح واریزه ممکن است، با ویژگی های مورفومتری بیشتر شود. هدف از این پژوهش تعیین سهم عوامل محیطی در پراکنش سطوح واریزهای است. در ابتدا در جنوب شهرستان پاوه، 419 سطح واریزهای با روش طبقهبندی نظارت شده تصاویر سنجش از دور شناسایی شدند. در بررسی اثر عوامل محیطی روی پراکنش واریزه، پارامترهای شیب، جهت دامنه، انحناء، طبقات ارتفاعی و تابش خورشیدی با استفاده از مدل رقومی ارتفاعی و توابع تحلیل مکانی آرک جی.آی.اس. استخراج شدند. عامل شیب در پنج طبقه، جهت دامنه در هشت طبقه، تابش خورشیدی در پنج طبقه و انحنای زمین، طبقه بندی شدند. خصوصیات این پارامترها به محدوده های واریزهای و غیر واریزهای تخصیص یافت. برای مناطق غیر واریزهای نقاطی به صورت تصادفی انتخاب شدند. ویژگی های مورفولوژیک آنها محاسبه برای اطمینان از نرمال بودن داده آزمون کلموگرف - اسمیرنف اجرا شد. داده مکانهای غیر واریزه در سطح اطمینان (15/0p-value >) نرمال تشخیص داده شدند. داده های واریزه نیز پس از انجام تبدیل باکس- کاکس نرمال شدند (13/0p-value >). مقایسه میانگین پارامترهای هر محدوده به روش آنالیز واریانس انجام شد. واریانس بین متغیر وابسته و عوامل شیب، جهت دامنه، ارتفاع از سطح دریا، فرم زمین، میانگین انرژی دریافتی از خورشید بررسی شد. نتایج نشان داد که تفاوت شیب، جهت دامنه، انرژی دریافتی از خورشید و فرم دامنه و ارتفاع در انتشار نقاط واریزه از نظر آماری در سطح 05/0P > معنادار است. برای نقاط غیر واریزهای فقط در عامل انرژی دریافتی و نقاط تصادفی تفاوت بین آنها معنادار بود و در سایر عوامل تفاوت معناداری در سطح 05/0 P > مشاهده نشد. اثر عامل شیب یعنی طبقه 25 تا 35 درجه، جهت جنوبی شرقی، میزان آفتاب گیری و جهت دامنه نسبت به سایر طبقه ها در پراکنش واریزه بیشتر است.کلیدواژگان: واریزه، شیب، دامنه، تحلیل واریانس، پاوه
تعیین الگوی استقرار طبیعی زادآوری زایشی بلوط ایرانی در شرایط مختلف رویشگاهی به منظور استفاده در احیای جنگل های زاگرسصفحات 53-63شناخت الگوی استقرار زادآوری طبیعی به منظور تقلید از آن در جنگل کاری، گام مهمی در راستای احیای جنگل های زاگرس است. در این راستا، پژوهش حاضر با هدف بررسی وضعیت استقرار طبیعی زادآوری زایشی بلوط ایرانی در سه توده از جنگل های حفاظت شده دالاب استان ایلام، با شرایط توپوگرافیک متفاوت، طی فصل بهار و تابستان 1395 انجام شد. در هر توده ، یک ترانسکت پایه در جهت عمود بر شیب دامنه پیاده و روی آن موقعیت های استقرار زادآوری شامل «زیر تاج درخت»، «زیر و پناه درختچه «، «زیر و پناه بوته»، «کنار سنگ» و «فضای بدون پوشش» انتخاب شد. برای هر موقعیت استقرار زادآوری، سه تکرار انتخاب و برای هر کدام، یک پلات دایره ای شکل 15 متر مربعی دائمی پیاده شد. در هر پلات، تعداد نهال ها و بلندی آنها اندازه گیری شد. نتایج نشان داد که بیشترین میزان زادآوری بلوط ایرانی در جهت شمالی و ارتفاع 1400 متر از سطح دریا، زیر تاج درختان بلوط و بنه، در سمت شمالی تاج درختان و در فاصله ثلث اول شعاع تاج درخت است. کمترین میزان زادآوری بلوط، بسته به شرایط رویشگاه، در زیر و پناه بوته ها، کنار سنگ ها و فضای آزاد بوده و در زیر تاج درختان کیکم، زادآوری بلوط یافت نشد. بیشترین تراکم نهال های بلند در فاصله ثلث سوم شعاع تاج درخت و کمترین میزان آنها در فاصله ثلث اول شعاع تاج درخت بود. نتیجه آنکه تاج درخت، مهم ترین نقش را در استقرار نهال و پرستاری آن در مقایسه با سایر موقعیت های استقرار زادآوری در جنگل دارد. با توجه به استقرار قابل توجه زادآوری در زیر و پناه درختچه ها و بوته ها، می توان به نقش موثر آنها در حمایت نهال ها و بزرگ شدن آنها اشاره کرد. بر اساس نتایج بالا، می توان الگوی استقرار زادآوری طبیعی بلوط را برای احیای جنگل های زاگرس پیشنهاد داد.کلیدواژگان: استقرار زادآوری طبیعی، بلوط ایرانی، احیای جنگل، عوامل بیولوژیک، جنگل های زاگرس
صفحات 65-79مسکن جزء نیازهای اولیه و اساسی زندگی فردی و اجتماعی انسان است. در اقتصاد توسعه، اهمیت مسکن به حدی است که از جمله شاخص های توسعه و توسعه نیافتگی کشورها محسوب می شود. این پژوهش، به منظور بررسی عملکرد و چگونگی تاثیر متغیرهای کلان اقتصادی شامل درآمد سرانه خانوار، شاخص قیمت کل سهام، نرخ تورم، قیمت مصرف کننده خانوار شهری و تعداد پروانه های احداث ساختمان مسکونی در الگوی رفتاری قیمت مسکن در کشور با بهره گیری از روش های رگرسیونی ساده، چندمتغیره و مضرس انجام شد. نتایج حاصل از رگرسیون خطی ساده و چندمتغیره نشان داد که به ترتیب وجود همبستگی سریالی مثبت و هم خطی چندگانه باعث پایین آمدن قابلیت و عدم اعتماد به این مدل ها شده است. از سویی نتایج نشان داد که متغیر پروانه های مسکونی دارای رابطه خطی معنی داری با قیمت مسکن نیست و متغیر نرخ تورم تنها در صورت حذف داده سال 1393 از رابطه خطی معنی دار با قیمت مسکن برخوردار می شود. در ادامه با ترسیم نمودار مضرس در دامنه از 01/0 تا 52/0 مشخص شد که ضرایب رگرسیونی مدل های چندمتغیره در عدد مضرس 08/0 و 1/0 پایدار می شوند؛ بنابراین با اتخاذ اعداد مضرس یادشده، مدل های رگرسیونی با ضرایب رگرسیونی واقعی بازتولید و مشخص شد که در یک مدل ترکیبی، متغیرهای درآمد سرانه خانوار، قیمت مصرف کننده خانوار شهری، نرخ تورم و شاخص کل قیمت سهام به ترتیب با ضرایب بتای 349/0، 348/0، 288/0 و 0612/0 مقدار، در قیمت مسکن شهری ایران موثر هستند. به طور کلی، نتایج این مطالعه نشان داد که چون متغیرهای کلان اقتصادی معمولا از شرط تعامد برخوردار نبوده و دارای رابطه خطی هستند؛ لذا، به منظور ارائه مدل های واقعی تر که از قابلیت برون یابی مناسب برخوردار باشند، ضرورت دارد که از رگرسیون مضرس استفاده شود؛ چراکه روش حداقل مربعات در این موارد، برآوردهای غیرواقعی از ضرایب متغیرهای رگرسیونی ارائه می دهد.کلیدواژگان: قیمت مسکن، رگرسیون مضرس، نرخ تورم، همبستگی سریالی، ایران
ارزیابی پایداری اکوسیستم با استفاده از روش اتحادیه بین المللی حفاظت از طبیعت (مطالعه موردی: حوضه آبخیز دروک)صفحات 81-93ارزیابی پایداری حوضه آبخیز به روش اتحادیه بین المللی حفاظت از طبیعت، تکنیکی برای درک و اندازه گیری توسعه پایدار است. این تکنیک، امکان مقایسه شرایط موجود منطقه را با وضعیت ایده آل خود، یعنی توسعه کامل انسانی و یک اکوسیستم سالم و مولد را فراهم می آورد. این روش، به صورت هم زمان، پایداری اکوسیستم و پایداری انسانی را بررسی می کند. در پژوهش حاضر، پایداری حوضه آبخیز دروک با استفاده از روش اتحادیه بین المللی حفاظت از طبیعت، توسط 7 معیار و 17 شاخص در بخش انسانی و 8 معیار و 18 شاخص در بخش اکوسیستم بررسی شد. در این پژوهش، حوضه آبخیز دروک، به دو بخش با نام های آق چشمه و قلعه قافه تقسیم و اندازه گیری ها در هر بخش، به صورت مجزا انجام شد. معیار آموزش و پرورش، مهارت و فقر در هر دو زیرحوضه در شرایط متوسط است. با افزایش میزان اشتغال جوانان، می توان باعث کاهش میزان وابستگی و بهبود وضعیت معیار فقر شد. معیار تامین و سلامت مواد غذایی در هر دو زیرحوضه قابل قبول است. معیار عدالت و برابری در شرایط ضعیف و قابل قبول به ترتیب در زیرحوضه های آق چشمه و قلعه قافه است. امتیاز نهایی زیرحوضه قلعه قافه برابر با 44 و امتیاز نهایی زیرحوضه آق چشمه، 61 است. به طور کلی، امتیاز هر دو زیرحوضه، نشان می دهد زیرحوضه ها از نظر پایداری در محدوده متوسط قرار دارند؛ همچنین، امتیاز نهایی حوضه آبخیز دروک، برابر با 52 است که در محدوده وضعیت متوسط است. بررسی شاخص ها نشان داد، حوضه مورد نظر از لحاظ وضعیت کاربری و فرسایش نسبت به سایر شاخص ها در وضعیت بسیار نامناسبی قرار دارد و این شاخص، بیشترین تاثیر منفی را در حوضه مورد نظر دارد.کلیدواژگان: اکوسیستم، توسعه پایدار، حوضه آبخیز، اتحادیه بین المللی حفاظت از طبیعت
صفحات 95-111نظارت بر جنگل، نیازمند سیستم های خودکار برای تجزیه و تحلیل داده های حجیم سنجش از دور است. داده های ماهواره ای، به عنوان سریع ترین و کم هزینه ترین روش ها، به منظور تهیه نقشه پوشش اراضی، در اختیار پژوهشگران قرار دارند. با توجه به تغییرات وسیع کاربری ها و تخریب جنگل در سال های اخیر، تولید نقشه گستره جنگل و بررسی روند تغییرات آن در دوره های زمانی مشخص، ضروری است. پژوهش حاضر، می کوشد تا از تصاویر لندست در بازه زمانی 27 ساله، تغییرات پوشش زمین های شهرستان کلیبر، به ویژه پوشش جنگلی را با استفاده از تکنیک های فازی شیءگرا بررسی کند؛ به همین منظور، تصاویر سنجنده تی.ام.لندست 5 (سال 1990)، سنجنده ای.تی.ام. پلاس لندست 7 (سال 2000 و 2010) و سنجنده او.ال.آی. تصویر لندست 8 (سال 2017) استفاده شد. در این پژوهش، به منظور بهبود نتایج قطعه بندی تصویر و به دنبال آن، افزایش دقت نتایج طبقه بندی، از الگوریتم پیش بینی مقیاس بهینه برای بهینه سازی مقیاس استفاده شد.بررسی نتایج نشان داد که شهرستان کلیبر، در فاصله سال های 1990 تا 2017، شاهد روند کاهشی اراضی با پوشش جنگلی و مرتعی درجه 1 بوده و از سوی دیگر، زمین های مرتعی درجه 2، بایر و اراضی مسکونی افزایش یافته و این امر، بیانگر روند کلی تخریب در منطقه از طریق جایگزینی مراتع درجه 1 و جنگلی با سایر کاربری ها نظیر مرتع درجه 2 و اراضی بایر و مسکونی است. در مدت 27 سال، اراضی جنگلی در این شهرستان به میزان 1/5% معادل 107 کیلومتر مربع کاهش داشته است.عوامل زیادی در تغییر پوشش جنگل در منطقه موثر هستند، از جمله افزایش مراکز سکونت گاهی، تخریب جنگل ها و تبدیل آن به زمین های کشاورزی را می توان نام برد.کلیدواژگان: پوشش جنگلی، فازی شیء گرا، سنجش از دور، تصاویر لندست
Stability Analysis and Stabilization Solutions for Landslides (Case Study: Khorramabad-Pole Zaal Freeway)Pages 1-17As for the increasing construction of buildings, roads, railways and others in the mountainous areas and steep, stabilizing the natural and artificial slopes is more and more considered. There are innumerous methods for slope stabilization in which they are trying to increase the resistant forces for driving forces. Therefore, the safety factor increases. The purpose of this study was to estimate the stability of dominant sliding slopes on the roads and the role of nailing and tracing on the stabilization of these slides on 40 km the Khorramabad-Pole Zaal freeway. In this research, at first, 8 sliding slopes along the roads were found. Using field study sampling and analysis of soil, topography and mining slope stability factor domains, all the parameters of slope stability analysis, including cs: soil cohesion, cr: root cohesion, φ: internal friction angle of soil, γd: soil density and γw: wet density of soil, were entered these parameters in slope stability analysis software and the safety factor were determined for each slide. we can identify the unstable slopes by this method and determine the protection operations to increase stability factor, so that nailing action in slide 6 with very high vulnerability class, the location of 33° 20' 43" north latitude and 48° 10' 59" E increases the stability factor from 0.57 to 1.98 and the tracing mechanism in the slope, increases the stability or safety factor at the value 2.10. And finally we can determine the best way to do the protective mechanism.
1-IntroductionOne of the main Ingredient stimulater of landslides, road construction, which is the basis for the large landslides by creating unstable trenches on both sides of the road, changing the course of rivers, unloading and loading unsuitable soil and dissection in trees forested areas and serious damages. The effects of mass movements on communication networks in several scientific disciplines were assessed. In addition, geo-morphologists and geologists studied the mechanism and the cause, the extent and number of landslides occurrence in various environments. Khorramabad-Pole Zaal freeway as a north-south transit highway, is one of the anfractuous mountain paths which is always in danger of road closure due to excessive expansion and various geo-morphological units. However, most risks that threatened this axis have often the geomorphological- climate origin which have created innumerous casualties and property damages due to of the lack engineering strategies and structures or counting non-significant the geomorphological parameters of present and future. The purpose of the slope stability analysis, is to offer appropriate safety coefficient providing stability. Therefore, recognizing the slope stability factor is necessary to prevent mitigation risks and damages.
2-Materials And MethodsAs the first step, the slopes along the road were determined. After the determining the slopes and the sliding slopes, all the model parameters were checked and determined by field studies. Then the samples were delivered to the technical and soil mechanic laboratory. Kayasta (2006) and Vinh (2007) were used to measure and specify the root cohesion for the analyzed slopes. Besides, these measures were used for different land uses. The determined parameters included: cs: soil cohesion, cr: root cohesion, φ: internal friction angle of soil, γd: soil density and γw: wet density of soil. Determining these parameters, they were measured. Finally, the parameters were entered slope stability analysis to determine safety factor for each slope.
3-Results And DiscussionIn this research, the stability of 8 sliding slopes along the roads was analyzed. One profile (to the depth of bedrock) was dug to measure each parameter in every profile. After delivering the samples to the soil laboratory, the essential parameters were measured to perform the slope stability model. Stability coefficient for slope number 6 is 0.57 and for the slope 8 is 1.17. As For the classification proposed by Peck et al. (1998), the slope number 6 is located in the class of very high landslide invulnerability, while the slope number 8 is in the class of is high vulnerability. Due to the slope stability factor (FS) in range Case based on the slope stability analysis and compare it with the actual conditions, it can be concluded that the slops 2 and 5, according to the table (4) are put in a low instability class. In other words, these slopes are considered stable. (FS>1.5) and no slide could be observed the slops 1 and 4, in the class average vulnerability (1.25> FS>1.5). So it can be argued that these slopes may not slip by themselves in nature. However, some man-made factors such as road constructing have been effective on making slides in these slopes.
4-ConclusionIn this research, the stability of 8 sliding slopes along the freeway Khrmabad- Plzal was studied. Besides, sustainable ways were found using the softwareFLAC SLOP. Two types of protective mechanism (Nailing and Terracing) in a slope slide were modeled to increase the safety factor. The findings showed that computing stability factor of slopes we can detect the unstable slopes and some protective mechanism could be specified to increase the stability factor or factor of safety. Protective mechanism as nailing and tracing increase the safety factor and reduce the driving forces protective mechanism as they can be decrease the stability of the slides prone to landslides. The results from nailing mechanism in the slope number (6) with a very high vulnerability class, increases the factor of safety from 0.57 to 1.98 and the terracing mechanism in the slope, increases the stability or safety factor at the value 2.10. And finally we can determine the best way to do the protective mechanism.Keywords: Factor of Safety, Nailing, Terracing, Landslide, Khorramabad-Pole Zaal Freeway
Pages 19-34The environment and development are two major concerns worldwide. The state of being under the influence of human activities and the increase in demands for resources utilization is a factor which prompts researchers to vulnerable areas and take necessary measures where it is required to manage and protect the environment and sustainable development. In this study, environmental vulnerability index EVI of Lorestan province with characteristics of natural impacts (topography, climate, geology, vegetation index NDVI, water density), environmental impacts (erosion, land use, DRASTIC index) and human impacts (road density, population density and waste depot location), have been investigated. For this purpose, two analytic hierarchy process AHP and weighted linear combination WLC , based on the geographic information system, have been used. Environmental vulnerability impact maps of the two methods were categorized in 5 classes of very low, low, moderate, high and extreme vulnerability. Based on the results of the AHP method, 1.76% of the province with an area of 482.1 km2 is located in the category of extreme vulnerability. Also, based on the results of the WLC method, 14.18% with an area of 3998.4 km2 was placed in the category of extreme vulnerability. Hot spots in the province include the center and south of Aleshtar City, the center and east of Khorramabad City, the center and east of Boroujerd City, Doroud center, north and east of Aligoudarz and northern Azna. In the cities of Kouhdasht, Rumeshkan, Doureh and in the west of the city of Poldokhtar and northwest and south west of Nourabad known as hot spots. Finally, the priority of vulnerability to surface and underground water resources, vegetation and soil was determined in the province.
1-IntroductionThe environment and development are two major concerns worldwide. The state of being under the influence of human activities and the increase in demands for resources utilization are the factors which prompt researchers to identify vulnerable areas and take necessary measures when it is required to manage and protect the environment and express sustainable development. Therefore, the aim of this study is to determine the spatial pattern of environmental vulnerability in Lorestan Province, through which the critical points of the province and the contribution of natural and human factors to the vulnerability of the regions are identified.
2-Materials And MethodsEnvironmental vulnerability index (EVI) of Lorestan Province has been investigated with characteristics of natural impacts (topography, climate, geology, Normalized Difference Vegetation Index (NDVI), and water density), environmental impacts (land use, DRASTIC vulnerability index and erosion) and human impacts (road density, population density and waste depot location). For this purpose, two methods of analytic hierarchy process (AHP) and weighted linear combination (WLC) have been used. To apply AHP, a questionnaire was designed to handle paired comparison between the criteria and their classes. Then, the relative importance of the elements was determined by 15 environmental experts and the weights ware calculated using the Expert Choice software. Subsequently, the vulnerability map was prepared according to this method. Also, for the weighted linear combination method, considering the importance of the classes of criteria and the expert opinion in relation to the terms of the study area, the threshold for the criteria was determined and the maps were standardized using the scale of 0-255 in Idrisi TerrSet software environment. So that, the symmetric fuzzy function was used for height, slope and vegetation index, the decreasing function was used for the average rainfall and waste depot location criteria. Besides, increasing function was used for geology, mean temperature, water density, road density, population density, land use, DRASTIC index and erodibility criteria. Then the vulnerability map was prepared and eventually, maps of the eenvironmental vulnerability index derived from the two methods were categorized into five classes of extremely low, low, moderate, high and severe vulnerability.
3-Results And DiscussionThe results showed that according to the analytic hierarchy process, 15.2 percent of the province's area was very vulnerable, 44.38 percent had a low vulnerability, 42.22 percent had a moderate vulnerability, 9.51 percent was located in the high vulnerable class and 1.76% was placed in severely vulnerable category. Therefore, the most area of the province was located in the low vulnerability category. According to the weighted linear combination method, 1.94 percent of the province's area was very vulnerable, 12.25 percent had a low vulnerability, 30.50 percent had a moderate vulnerability, 41.14 percent was located in the high vulnerable class and 14.18% was placed in severely vulnerable category. Therefore, based on this method the most area of the province was located in the high vulnerability category. Compared to the analytic hierarchy process, the hot spots in the province through weighted linear combination method were more extensive. The size of the environmental vulnerability classes differentiated by elevation categories showed that the altitudes of 191-1000 includes the highest range of hot spots compared to the extent of its province's coverage. After that, the altitudes of 1000-2000 and 2000-3000 were ranked second and third, respectively. The extent of the vulnerability classes differed by the counties of Lorestan Province showed that based on the area of each county, Aleshtar has the highest rate of vulnerability than any county. Subsequently, Boroujerd, Doroud, Khorramabad, Poldokhtar, Aligoudarz, Nourabad, Azna, Roumeshkan, and Kouhdasht are in next categories respectively. Most identified hot spots were distributed in center and south of Aleshtar, center and east of Khorramabad, center and east of Boroujerd, north and east of Aligoudarz and north of Azna. Also these spots can be recognized dispersedly in Kouhdasht, Roumeshkan and Doureh, north of Poldokhtar and northeast and south of Nourabad.
4-ConclusionThe investigation of the vulnerability condition of recognized hot spots in the counties of the province showed that the effective factors in the increasing of environmental vulnerability vary based on the county. This means that in Aleshtar, Khorramabad, Boroujerd, Doroud, Aligoudarz and Azna counties, agricultural and urban land uses had the highest role in the environmental vulnerability, while in Kouhdasht, Roumeshkan and Doureh counties oak forests and in Polodokhtar and Nourabad, agricultural lands and sensitive geological structure have been effective in the increasing of vulnerability and recognition of hot spots. Recognizing the vulnerability hot spots and their most important formation factors in county level can determine the priority of environmental policy and planning for mitigating the environmental vulnerability level.Keywords: Environmental Vulnerability Index, Hot Spot, AHP, WLC, GIS, Lorestan Province
Evaluation of Morphometric Factors on the Distribution of Debris: A Case Study on the Attica Ripples on the South of Paveh- Kermanshah Province, IranPages 35-51Scree slopes are the evidence of rock behavior against the fluctuations of temperature and humidity.The goal is to determine the contribution of geomorphologic and solar radiation factors to the distribution of destructive evidence. In the study area, there are many debris with bright, uncoated tones. Initially, 414 scree slope zones were identified by classification method on a remote sensing image. Then, in order to investigate the effect of environmental factors on variance distribution, slope parameters, amplitudes, curvature, elevation classes and solar radiation were extracted using DEM and ArcGIS spatial analysis functions. The slope factor in five Classes, direction the eight-class aspect, solar radiation, was classified into five classes and curvature, and the characteristics of these parameters were assigned to scree slopes and non-scree slopes boundaries. Besides, some points were randomly selected for non-scree slopes areas. Their morphological data were calculated to ensure that the Kolmogorov-Smirnov test data were normal. Data of non-scree slope locations were detected at a confidence level of p-value> 0.15 normal, but the data transformation after the conversion of the box-cox were normalized (p-value> 0.13) .The mean comparison of each parameter was done by ANOVA method. The variance between the dependent variable and slope factors, direction of aspect, altitude, ground curvature, mean of the energy received from the sun was investigated. The results showed that the slope difference, the direction of altitude, and the energy received from the sun are statistically significant at P> 0.05. For non-scree slopes points only significant difference was found between the energy factor and the random points, and in other factors there was no significant difference in the level of P> 0.05. The effect of the slope factor is 25 to 35 degrees, to the southeastern direction, the amount of sunshine and the direction of the range is greater than the other classes in the distribution of debris.
1-IntroductionIdentification of topographic factors and their effects on distribution of rock mass destruction is one of the most important tools for management and protection of natural hazards in mountainous regions. This can be risky in terms of rainfall and inappropriate interference in the environment. Stone deposition is a demonstration of active processes of destruction and erosion on the slopes. The Paveh and Oramanat Highlands: There are many destructive areas. The northern and southern slopes of the Hashtagh Mountain, which are parts of the Zagros Mountain belt, have a steep gradient. The average annual rainfall is 650 mm and the average annual temperature is estimated to be 13.5 ° C. At high altitudes, snow and ice are dominant in the winter and spring months. Sloping slopes, and deep valleys are the main characteristics of this area. The sun's shadow, in these complications and the deep valley, is further increased. The slopes located in the shade of the sun, the snow cover is more. Morphology is a combination of slopes, shapes and slopes distributed at various altitude levels. In terms of rock formations, the complex is composed of Sarvak, Garu, Ilam and Amiran. Thick lime and thin layer of dark gray with organic marls rich in gravel formations. On the Gora Formation, there are thick limestone limestones of the Ilam Formation. The Elam Formation here is a fine-grained, fine-grained limestone with regular layering, in which thin layers of black shale are also seen. The northern and southern edges of the Mount of Fire are composed of rocks of the Ilam Formation.
2-Materials And MethodsDue to mechanical destruction and weathering of the rocks on the slopes, there is evidence of Screeslope. Since scree slope is distributed on slopes and directions, the effects of slope, direction and height on the morphological behavior of the scree are not the same. To identify and distinguish this phenomenon, the Sentinel image was used in a supervised classification. After classifying the image, the classes were divided in scree and non-scree. A Google image with field views was used to control the classification results. An area of 120 square kilometers was identified on the classified image. The network was designed in two dimensions in two kilometers. Fourteen and nineteen degraded areas were identified within this network. Lithological and climatic geo-factors are assumed to be the same and the same 120 kilometers square. In the next step, morphometric parameters were calculated from a 30-meter elevation digital model. The slope parameters, aspect slopes, curvature, hypsometry and solar radiation were extracted using digital elevation model and ArcMap functions. The gradient factor were classified in five classes (treatment), the aspect slopes in eight treatments, and solar radiation in five treatments. Characteristics of these parameters are assigned to the degradation areas. The Kolmogorov-Smirnov test was performed to ensure that the data were normal. Non-destructive place data were detected at a confidence level of -0.15 p-value> normal. However, the data after the conversion of the box-box were normalized (p-value> 0.13). In the normal test, assuming the data is normal, a descriptive statistical descriptor for the distribution of variance was extracted in terms of factors and treatments. Variation points were randomly selected, their morphological characteristics were calculated, 419 degraded areas were identified, for each slope, slope, elevation and energy received from the sun were calculated for each range. The comparison of the average parameters of each limitation to the analysis of variance was done. Variance between dependent variable and slope factors, direction of amplitude, altitude, form earth, the average energy received from the sun was investigated.
3-Results And DiscussionThe results showed that the difference in slope, aspect slopes, energy received from the sun and the shape of aspect slopes and height in the distribution of scree was statistically significant at P> 0.05. For non-destructive points only significant difference was found between the energy factor and the random points, and in other factors there was no significant difference in the level of P> 0.05. The contribution of the slope factor, namely, 35 to 25 degrees, is much higher than the other treatments in the southeast. The effect of the amount of sun radiation and the direction of the aspect seems to be a large contribution to the distribution of the level of irrigation in the region. These factors seem to be affecting the debris flow. Despite the fact that the studied area was very rough; slope, elevation, and different solar radiation were classified into regular classes, but tendency to accumulate degradation was observed in special classes. 50% of the scree was distributed at a height of 1500 to 1800 m. The focus of burial activity in the small altitudinal area, as well as the slopes of 25 ° to 35 °, is that the eastern slopes indicate the existence of special patterns in the distribution of scree. Even the distribution of scree surfaces has spread through the waterways due to displacement caused by rainfall, flood and snow avalanches.
4-ConclusionGeomorphologic and statistical analyses were performed to analyze how morphometric features may contribute to degradation. The distribution of scree showed that destructive activities are active in the walls and rocky cliffs. Bright, uncovered, and rocky fall, the distribution of the gravel with the characteristics of slope, the direction of the slope, the altitude and the effect of the slope and direction of the slope on the solar radiation values were investigated. Four patterns were identified for the distribution of varieties. The first pattern, in the direction of the southeast, east, and northeast, was more than other directions in the degradation dispersion. In the second pattern, the highest frequency variation was observed in the slope of 25 to 35 degrees. In the third pattern, the vibrant active focus is on the altitudes of 1500 meters to 1800 meters above the sea level. Fourth pattern is classified based on the radiation.Keywords: Scree Slopes, Aspects, Solar Radiation, ANOA, Paveh
Determining the Natural Establishment Pattern of Quercus Persica Generative Regeneration in Different Site Conditions to Restore Zagros ForestsPages 53-63Recognizing the establishment pattern of natural regeneration to imitate it in reforestation is an important step towards the restoration of Zagros forests. In this regard, the present study was conducted to investigate the status of natural establishment of generative regeneration of Quercus persica in three stands of Dalab protected forests, Ilam province, with different topographic conditions during spring and summer of 2016. In each stand a basic transect was established perpendicularly to the slope in which the regeneration establishment positions including "under the tree crown", "under the shrub", "under the bush", "next to the rock" and "bare space" were selected. For each regeneration establishment position three replications were selected and for each of them a circular permanent plot with area of 15m2was established. In each plot the number of seedlings and their heights were measured. Results showed that most amount of Q. persica regeneration is in north aspect and the height of 1400 m above sea level, under the crown of Q. persica and P. atlantica trees, in northern side of tree crowns and at a distance of the first third of tree crown radius. The lowest amount of oak regeneration depending on site conditions was at under the bushes, next to the rocks and in bare spaces. There was no oak regeneration under the crown of A. cineracens trees. The most density of tall seedlings was at a distance of the third third of tree crown radius and the lowest amount of that was at a distance of first third of tree crown radius. It was concluded that the tree crown has the most important role in seedling establishment and it is nursing in comparison with other regeneration establishment positions in the forest. Given the remarkable establishment of regeneration under the shrubs and bushes, to their effective roles in supporting of seedlings and their growing can be mentioned. Based on the above results, the natural regeneration establishment pattern of oak for restoration of Zagros forests can be proposed.
1-IntroductionRegeneration is a valuable natural process through which plants can be reestablished and this strategy helps plants to sustain and preserve their diversity and genetic identity. Nowadays, natural regeneration in Zagros forests has faced fundamental problems and the regeneration amount of tree and shrub species has reduced quantitatively and qualitatively. Performed seeding in forested areas could not be yet effective contributing to improve the regeneration of these forests. It seems that one of the contributing ways to overcome this problem is to find out how to establish natural regeneration in different site conditions of these forests and to imitate its pattern during seeding in the field. In this regard, it was attempted to investigate some of the effective factors on regeneration such as the site topography and the seedling establishment position under the canopy cover or in uncovered area which are responsive to some needs of the seedling. So, the aim of this study is to investigate the quantitative and qualitative status of Persian oak generative regeneration in different topographic conditions and various regeneration establishment positions and determine its regeneration establishment pattern in Dalab protected forests, Ilam province.
2-Materials And MethodsIn this research, three forest sites were selected in Dalab region of Ilam province based on different site conditions (two northern and southern aspects and two classes of altitude, 1400-1450 m and 1500-1550 m above sea level). In each stand, one basic transect was established perpendicular to the slope and on it the regeneration establishment positions were selected and marked. The regeneration establishment positions were included "under the trees", "under the shrubs", "under the bushes", "next to the rocks" and "bare space". For each regeneration establishment position three replications was considered and for each of them a 15m2circular permanent plot was established. Inside the plots counting the number of seedlings and measuring their heights was done during the spring and summer of 2016. The present study was carried out in an experimental design of split plot. Collecting the data of two seasons spring and summer and their initial analysis, site conditions and regeneration establishment position on the amount of generative regeneration, analysis of data variance was performed by GLM test in SPSS software to study the effect of sampling season,. Also, the amount of regeneration and height of seedlings in different sides of tree crowns and in different parts of the crown with different distances from tree trunk were analyzed by one-way ANOVA.
3-Results And DiscussionThe most amount of Persian oak regeneration was found in the north aspect and height of 1400 m above sea level, under the crown of Persian oak and Wild pistachio trees, in north side of tree crowns and at a distance of first third of tree crown radius. The reason for this referred to the more favorable and cooler microclimate conditions of the northern slopes and the presence of more shadows and moisture in them and also the better micro-climatic conditions under the crown of trees than the other regeneration establishment positions and the more favorable and cooler conditions of the northern side of their crowns. The least amount of regeneration depending on site conditions was under the bushes, next to the rocks and in bare space and under the crown of maple trees was not found oak regeneration. This result suggests that, despite the light demanding nature of the Persian oak species, seedlings of this species need some shade in the early ages and should be sheltered by seed trees. The most density of tall seedlings was at a distance of third third of tree crown radius which is due to the light demanding of oak species that gradually with growing of its seedlings their optical needs is increased.
4-ConclusionIn all studied cases, the tree crown has the most important role in seedling establishment and its nursing compared to the other regeneration establishment positions in the forest. Also, given the remarkable frequency of regeneration under shrubs and bushes after the option of under the tree crowns, it can be mentioned to the effective role of these biological agents in supporting the seedlings, growing and protecting them from the risk of environmental factors, wildlife and particularly domestic animal grazing which could give us a model for reforestation. Therefore, it can be said that doing seeding or seedling planting to enrich and rehabilitate of western forests in straight and regular lines which are usually carried out by the executive organs, are not conclusive and to improve it successfully, reforestation should be done irregularly and in accordance with the natural establishment pattern of regeneration.Keywords: Biological Agents, Forest Restoration, Natural Regeneration Establishment, Quercus persica, Zagros Forests
Pages 65-79Housing is one of the basic and vital needs of individual and social life. In development economics, the importance of housing is so high that it is one of the indicators of development and development of countries. Using simple multivariate regression methods, this research was conducted to investigate the performance and the effect of macroeconomic variables including household income per capita, total stock index, inflation rate, urban household consumption price and the number of residential building mortalities on the behavioral pattern of housing prices in the country. This study aims to examine the performance and impact of macroeconomic variables on the pattern of housing prices in the country, using regression methods. Variables such as family income, the stock price index, inflation, the consumer price of urban households and the number of residential building permission were regarded as a regression variables. Simple and multivariate linear regression analysis showed that positive serial correlation respectively and severe multi-collinearity and lack of confidence in the ability of these models are coming down. The results showed that the variable of building permission has no significant linear relationship with housing prices and the variable of inflation rate will have a significant linear relationship with housing price only if the data of 1393 were removed. Then, in the range of 0.01 to 0.52 charting ridged was found that the regression coefficients multivariate models 0.08 and 0.1 are stable. So by adopting a structured exercise, regression models were reproduced by regression coefficients real numbers. It turns out that in a compound model, family income, the consumer price of urban households, inflation rate and total stock index affected the urban housing price of Iran as equal as 0.349, 0.348, 0.288, and 0.0612 respectively. The results of this study showed that since the macro-economic variables usually do not have orthogonality condition and have a linear relationship, it is necessary to use ridge regression to present real models having the extrapolate ability. Moreover, unrealistic estimates of regression coefficients provide regression variables.
1-IntroductionHousing is one of the basic and vital needs of individual and social life. In development economics, the importance of housing is so high that it is one of the indicators of development and development of countries. The long-term analysis of the housing market in Iran suggests severe fluctuations in the variables of this sector, including housing prices, fee and investment. These fluctuations had the greatest impact on the final cycle of housing, households, and these price changes, in addition to instability in planning, have provoked a negative psychological wave for people. Accordingly, the purpose of this research is to fit the model that can be efficient and with the use of variables, be able to predict the changes in the price of housing over time with the least error. Housing price fluctuations seem to be influenced by several factors in which there is a direct correlation between increased revenues and construction costs and rising housing prices (Wang & Zhang, 2014). Determining the contribution of each factors affecting housing prices, authorities can take an action to balance suppliers and applicants, which results in sustainability and rational development of housing prices in urban areas. Therefore, the comparative analysis of regression and ridge models, the identification of the instability and the falsehood of the factors determining the price of housing in the models are examined. This process will ultimately lead to the use of an appropriate model to increase the reliability and stability of these coefficients. Thus, a more realistic understanding of how urban housing prices behave in relation to macroeconomic variables can be achieved.
2-Materials And MethodsStatistical methods such as Pearson correlation coefficient, simple linear regression, multivariable regression and ridge regression were used to investigate the reaction of housing prices to independent variables. In this regard, at first, household income per capita data, total stock index, inflation rate of urban households, number of residential construction projects pertaining to the entire city of the country, as independent variable, and the housing price index of all cities in the country, as a dependent variable, from 2002-2014, were gathered from the Archives of the Center Statistics and Central Bank of Iran (2016).
3-Results And DiscussionIn spite of having significant coefficient, simple regression models are not trustworthy enough. As a matter of fact, there was a positive serial correlation between the residuals of these models, which indicates that there are other variables playing a decisive role in the housing market model.
Subsequently, using a multi-variable regression model, a model of housing price index was developed by adopting a combination of macroeconomic variables including household income per head, total stock index, inflation rate, urban household consumption price, and the number of residential construction mortgages. The results of the multivariate regression model, as in previous studies, showed that the combination of macro variables could significantly explain the behavioral pattern of urban housing prices in Iran (Soheilie et al., 2012). Housing price volatility is affected by several factors. As household income per head increases, housing prices also increases, which indicates a direct correlation between the independent variables and the function. The existence of such a connection is also seen in previous studies (Wang and Zhang, 2014; Ho et al., 2006). It is worth noting that these coefficients are not reliable. As all indexes, including the inflation index of variance, showed that due to the large error of the governor, regression coefficients (beta), the proposed model has no predictive capability and these coefficients are false. In order to solve this problem, ridge regression analysis was used. Coherency metrics such as Tolerance and ..., also showed the stability and reliability of this coefficient. However, the results of multiple coherency measures in the model show the stability of the coefficients obtained for all independent variables by the ridge model. In this way, the damaged model managed to estimate the values of these coefficients successfully by interacting with multiple interactions, while decreasing the error width of the governor's coefficients. Indeed, the results of this study emphasize the use of the ridge model in studies on modeling and predicting housing prices.
4-ConclusionThe housing market is affected by macroeconomic variables, which is due to the volatility of these variables in its price pattern. Accordingly, this study was conducted to model the price of urban housing market throughout the country using regression methods The regression coefficients of ridge models are more realistic than the least squares method and have good extroversion, so that the inverse and false role played by the stock price index in two least squares regression models has now become a direct and actual role in ridge models. Generally, the results of this study, based on the used statistical measures, showed that the application of the ridge method by interfering multiple interactions between independent variables not only can estimate the stable values of the coefficients of influence, but also has a significant statistical significance to model housing price.Keywords: Inflation Rate, House Price, Serial Correlation, Regression Ridge, Iran
Pages 81-93Sustainable Sustainability assessment using IUCN is a technical tool to understand and measure sustainable development. This technique allows comparing the existing conditions of the region with its ideal state, namely, full human development and a healthy and productive ecosystem. This approach simultaneously examines ecosystem sustainability and human sustainability. In this study, Dorook basin sustainability was assessed using IUCN method by 7 criteria and 17 indicators in the human section and 8 criteria and 18 indicators in the ecosystem section. In this study, Dorook basin was divided into two sub-basin called Aghcheshmeh and Ghaleghafeh. The measurements were done in each sub-basin separately. The results of analysis indicated that relation to sustainable human criterion and indicators, land use changes is the lowest score criterion. The criterion is moderate in education, skill and poverty in both sub-basins. By increasing youth employment, it can reduce dependency and improve the standard of poverty. The food security and nutrition standards are acceptable in both sub-basin. The criterion of justice and equality is poor and acceptable conditions in sub-basins of Aghcheshmeh and Ghaleghafeh, respectively. The final score of the Ghaleghafeh sub-basin is equal to 44 and the final score of the Aghcheshmeh sub-basin is 61. Generally the scores of both sub-basins indicate that sub-basins are in the medium range in terms of sustainability. The final score of the Dorook basin is 52, which is within the medium range. Investigating the indices showed that the area in terms of land use and erosion in comparison with other indicators is in a very bad situation and this index has the most negative effect in basin.
1-IntroductionAccording to FAO studies, about twenty million hectares of forest have been planted from 1995 to 1980 in developed countries, while two hundred million hectares of forest has been reduced in developing countries during this period.
In contrast to other approaches, the IUCN method of Sustainability Assessment gives equal treatment to people and the ecosystem. It involves stakeholders in determining for themselves what sustainability means in their context. It uses, as its framework, a hierarchy of elements and objectives to translate the concept of sustainable development into concrete targets and measurable indicators. Thus making clear to all those involved what features everyone agrees contribute to measuring sustainability. The elements are designed to be tailored to local conditions and needs. The IUCN Sustainability Assessment Method is a user-focused process and thus can be used at international, regional, national, district or local scales. The IUCN Sustainability Assessment Method, in its full version, describes a process with seven stages. It is presented as a cycle because the assessment process is designed to allow updates that can show changes over time.
According to the IUCN method widely used in different countries, in this study a set of measurements was determined according to the IUCN sustainability assessment method and organized based on issues and concerns related to forests.
2-Materials And MethodsDorook Catchment is the political section of Golestan province, Minoodasht city, and central section. There are 13 Villages in the basin. This catchment is the most important in Golestan province because of deforestation and loss of forest.
A full Sustainability Assessment follows all seven stages in the assessment cycle. The general purpose of such assessment is to engage in reflection about sustainability, collect data for indicators, combine indicators and undertake analysis based on the indicators and use the data and process to assess priorities for action.
Many indicator models use the Pressure-State-(Impact)-Response model to identify and organize indicators. Pressure three key types of indicators one covering the element's state, one showing pressures and one showing the way society is responding to the problem. Sustainability assessment primarily uses 'state' indicators, because in most cases, they are the most reliable measure of an element. Pressure indicators are useful in instances where measuring the pressure that one area is having on another is preferable particularly cross border pollution, long-range transport of air or water pollutants and impacts on the global atmosphere. The use of response indicators is not encouraged in sustainability assessments, as it is often hard to link the state of an element with the responses society is undertaking to alleviate the problem.
Three main components of ecosystems have been used including forests; water environment and climate were a total of 18 indicators and eight criteria. 7 criteria and 17 indicators were measured in human wellbeing.
3-Results And DiscussionThe results of analysis indicated that the relation to sustainable human criterion and indicators, land use changes is the lowest score criterion. The scores of Ghaleghafi and Aghcheshme are 30 and 0 respectively, indicating that the rate of land degradation is high. Changing of forest to agricultural land is the most important role in reducing stability in Dorook watershed.
Education and skills criterion is medium in two sub-basin. Poverty criterion is medium in both sub-basin. In order to improve the conditions situation in the farms provide area youth by increasing employment rates, reducing dependency ratio. Food supply and food safety is in acceptable condition in both sub-basin. Justice and equality Criteria is in poor condition and acceptable in Aqcheshme and Ghaleghafi respectively.
Score of soil conservation criteria in Aghcheshme sub-basin is 0 and in Ghaleghafi sub-basin is 28 that seems reasonable according to land use changes made in the following basins. Water status map shows that both sub-basin in good condition and is acceptable and In general, water ecosystem are in a much better situation than forest and human ecosystems.
Weather and climate criteria in Aghcheshme sub-basins is in acceptable condition and in Ghaleghafi sub-basins is in the middle.
4-ConclusionSustainable development indicators are expressing such interaction model between society and the environment. In general, Dorook basin ecosystems in Ghaleghafi sub-basins socio-economic performance and water criteria is in stable condition and in Aghcheshme sub-basins conservation and soil conservation are in unstable condition. The entire watershed is in the middle range and change conditions to improve sustainability need to promote appropriate policies.Keywords: Ecosystem, IUCN, Sustainable Development, Basin
Evaluating the Pattern of Forest Cover Changes Using Fuzzy Object-Oriented Techniques (Case Study: Kaleybar County)Pages 95-111Forest monitoring requires an automatic systems to analyze large-scale remote sensing data. Nowadays with development of remote sensing technology, a large amount of spatial data is available. Satellite data is the fastest and cheapest method for researchers to provide land cover mapping. Considering the wide variation of forest usage and destruction in recent years, producing the map of the forest area and examining the process of its changes in certain time periods is necessary. In this research, we tried to investigate land cover changes in Kaleybar county during a 27-year period, especially forest cover using fuzzy object-oriented techniques using Landsat imagery. For this purpose, the TM Landsat 5 (1990), the ETM Landsat 7 (2000 and 2010) and the OLI Landsat 8 image for 2017 were used. In this study, ESP algorithm was used to optimize the scale in order to improve the image segmentation results and subsequently increase the accuracy of classification results. The result shows that there has been a decline in lands with forest cover and 1st grade pastures in Kaleybar county during the period from 1990 to 2017. However, we see the increment in 2nd grade pastures, arid and residential lands, which indicates the general trend of destruction in the region through the replacement of 1st grade pastures and forest lands by other uses such as 2nd grade pasture and arid and residential areas. In 27 years, the forest lands have fallen by 5.1 percent that is equivalent to 107 square kilometers. There are many factors affecting forest cover changes in the region, including the increase of habitation centers, deforestation and conversion of forest to farmlands.
1-IntroductionForest monitoring requires an automatic systems to analyze large-scale remote sensing data. Nowadays with the development of remote sensing technology, a large amount of spatial data is available. Utilization of the satellite data provides the fastest and cheapest method for researchers to prepare land cover mapping. In order to obtain a proper planning and management for natural resources, especially forests, accurate and timely information maps are required. Considering the wide variation of forest usage and destruction in recent years, it is necessary to prepare maps of the forest areas and to examine the changes occurred in them during certain time periods. The Arasbaran forest habitats, which were covering a large area in the past, are nowadays limited to the small parts of the Kaleybar, Khodafarin, Ahar and Jolfa counties in East Azarbaijan province with the total area of 140,000 hectares. Vegetation of Kaleybar county is very rich and important compared with other parts of the East Azarbaijan province and encompasses large forests with a variety of rare trees and natural grasslands, though it has suffered many changes in recent years. Therefore, this research tries to use object-oriented method, especially fuzzy object-oriented to increase the accuracy of Landsat images classification and the land use change trend, especially the forest cover of Kaleybar, for the period of 27 years from 1990 to 2017, while high spatial resolution satellite images are not available.
2-Materials And MethodsThe Kaleybar county has an area of about 2112 Km2 and covers 3.2 percent of East Azarbaijan province in its northeast. The purpose of this study is to evaluate the changes in the Kaleybar county with an emphasis on forest lands. For this aim, Landsat satellite images of TM Landsat 5, ETM Landsat 7 and OLI Landsat 8 with range of 1868 to 3300 from were processed with the eCognition Developer software for the period of 1990 to 2017 with 10 year time series. The fuzzy object oriented approach was used to extract the land cover of different vegetation indices, as well as homogeneous texture data, shape, compression and brightness. The results were then calculated and finalized in ArcGIS software after accurate evaluation.
3-Results And DiscussionIn this research, images in 200 scales sorted consecutively from 1 to 200 were segmented using low to high multi-functional hierarchical segmentation approach with shape coefficient of 0.4 and compression coefficient of 0.5 in order to construct LV graphs and the appropriate scales for image segmentation were determined using the plotted graphs. By predicting the appropriate scale for creating image units using the algorithm (ESP), the scale of 15 with coefficients of shape and compression 0.3 and 0.5 respectively was scaled as the appropriate scale for extraction of Landsat 5 and 7 satellite images, and the scale of 130 with shape coefficient of 0.4 and compression coefficient of 0.5 was chosen as the appropriate scale for Landsat 8 satellite OLI images. Classifying the selected images using the fuzzy object-oriented method, the land cover changes were calculated and mapped in the Arc GIS software. For the 27-year period, the largest changes have occurred in the forest and inferior lands. The difference was that forest lands have declined with negative gradient, and consequently, inferior lands have increased with positive gradient. In 27 years, forest land areas have decreased by 5.1 percent, equivalent to 107 Km2.
4-ConclusionThe purpose of this study was to detect land cover changes in Kaleybar county during 27-year period. For this, remote sensing satellite imagery was used and after preparing the land cover map for all four time periods, the area of six classes of land cover was obtained and the land cover changes map was extracted. To better comparison of the changes occurred in these four periods, these changes were quantitatively calculated. Results show that during the period from 1990 to 2017, there has been a decline in lands with forests and 1st grade pastures. On the other hand, it is seen that 2nd grade pastures, Bayer lands and residential have increased, which indicates the general trend of destruction in the region through the replacement of 1st grade pastures and forest lands by other uses such as 2nd grade pasture and arid and residential areas. During this 27 year period, the forest lands have decreased by 5.1 percent that is as equal as 107 km2. In this research, classification results with >90% accuracy for each of the four image periods of imaging indicate the ability of the fuzzy object-oriented method in land cover studies. The method applied in this study can determine the land cover changes over time, and also determine the land degradation trend quantitatively and accurately.Keywords: Forest Cover, Fuzzy Object-Oriented, Remote Sensing, Landsat Imagery