فهرست مطالب

نشریه جغرافیا و برنامه ریزی محیطی
سال سی و دوم شماره 3 (پیاپی 83، پاییز 1400)

  • تاریخ انتشار: 1400/10/01
  • تعداد عناوین: 7
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  • عاطفه صداقتی، محمدتقی پیربابایی*، فرشاد نوریان، حامد بیتی صفحات 1-30

    مفهوم «ارزش» در برنامه ریزی مسکن شهری ازجمله مفاهیم اعتباری و برساختی است که در صورت هماهنگی با روح حاکم بر جامعه، زمینه ساز تعامل منافع حاصل از الگوی توسعه مسکن شهری با منافع بهره وران آنهاست. پژوهش حاضر با هدف ارزشیابی مسکن شهری برنامه ریزی شده از نگاه ساکنان، در پی تبیین مفهوم ارزش در برنامه ریزی مسکن شهر تبریز مطابق با فرهنگ و اندیشه اسلامی حاکم بر جامعه با رهیافت واقع گرایی اسلامی مبتنی بر دیدگاه ارزش شناسی علامه طباطبایی و با تاکید بر نظریه اعتباریات وی و با استفاده از راهبرد پژوهش پس کاوی انجام شده است. از آنجا که بسیاری از ویژگی های تبیین کننده ارزش مسکن شهری در بازار به طور مستقیم دادوستد نمی شوند، به منظور کمی سازی ارزش ها از مبانی اولیه مدل هدانیک بهره گرفته شده است. شاخص های ارزش مسکن شهری و مدل تبیینی در شهر تبریز (در قالب سه نمونه شهرک رشدیه، کوی اشکان و مجتمع چمران) مورد آزمون و تحلیل همبستگی و رگرسیونی (به شیوه خطی و شبه لگاریتمی) قرار گرفتند. یافته های پژوهش نشان می دهد مقوله «ساختاری- فیزیکی» بنا در کنار مقوله «محیطی» مربوط به دسترسی به کاربری ها، بیشترین قدرت تبیین کنندگی متغیر ارزش مسکن شهری تبریز را دارند؛ حتی در نمونه های کاملا برنامه ریزی شده در شهر تبریز (شهرک رشدیه) نیز، همه مقولات موثر ارزش بخش مسکن شهری پوشش داده نمی شوند. با عنایت به اینکه بومی بودن الگوی توسعه مسکن در محور ارزش های حاکم بر جامعه تحقق خواهد یافت و ارزش، یک مقوله فرهنگی است، ضرورت دارد شناسایی ارزش ها در هر جامعه روی دهد و برنامه ریزی مسکن شهری براساس آن هدایت شود؛ در این صورت شهرها در بازنمایی فرهنگ اسلامی موفق خواهند شد.

    کلیدواژگان: مفهوم ارزش، برنامه ریزی مسکن، شهر تبریز، اندیشه اسلامی
  • سمانه میرعلیجانی، محمدامین خراسانی* صفحات 31-46

    مفهوم کیفیت زندگی، عنصری کلیدی در سیاست گذاری و بررسی سیاست های حوزه عمومی است و شاخص توسعه اجتماعی در نظر گرفته می شود؛ از این رو هدف پژوهش حاضر، بررسی مقاله های علمی پژوهشی منتشرشده در ارتباط با کیفیت زندگی روستایی ایران طی سال های 1390 تا 1398 است. بدین منظور تمامی مقاله های منتشرشده طی این سال ها ازنظر جنسیت و تعداد نویسندگان، تخصص نویسندگان، گرایش های موضوعی، محدوده های مطالعه شده، سهم استان ها و فصلنامه ها بررسی شده است. جامعه آماری پژوهش، تمامی مقاله های منتشرشده طی سال های 1390 تا 1398 شامل 95 مقاله بوده است. روش پژوهش، تحلیل محتواست و اطلاعات به صورت کتابخانه ای گردآوری شده است. داده ها با نرم افزار Excel و spss محاسبه و نتایج به شکل شماتیک نمایش داده شده است. نتایج نشان می دهد از 95 مقاله منتشرشده، حدود چهارپنجم را مردان نوشته اند که حاکی از نیاز به مشارکت بیشتر زنان درزمینه تولید محتوای علمی درباره کیفیت زندگی روستایی است؛ همچنین درزمینه تخصص نویسندگان، بیشترین تخصص به رشته برنامه ریزی روستایی و درزمینه وابستگی سازمانی نویسندگان، بیشترین وابستگی به دانشگاه های دولتی مربوط است که از این بین، دانشگاه تهران سرآمد دیگر دانشگاه هاست. از میان موضوعات مدنظر نویسندگان، بیشترین تعداد مقاله ها به ارزیابی کیفیت زندگی اختصاص دارد؛ همچنین دو فصلنامه پژوهش های روستایی و پژوهش های برنامه ریزی روستایی توجه بیشتری به مقوله کیفیت زندگی داشته اند.

    کلیدواژگان: کیفیت زندگی، کیفیت زندگی روستایی، مقاله علمی پژوهشی، تحلیل محتوا
  • مجید کریم پورریحان، ناصر مشهدی*، اعظم بیگی صفحات 47-66

    پوسته های تبخیری خاک که از انواع فرایندهای فیزیکی، شیمیایی و بیولوژیکی تشکیل شده اند، در تثبیت خاک در مناطق نیمه خشک و خشک نقش مهمی دارند. پایداری و یکپارچگی این پوسته ها با فعالیت های انسانی مانند تردد دام یا ماشین یا استخراج مواد معدنی به خطر می افتد. هدف پژوهش حاضر، بررسی اثر استخراج سولفات سدیم و تخریب پوسته تبخیری بر رفتار حفاظتی سطح زمین است. این پژوهش در منطقه ایوانکی انجام شد. در این راستا چهار نمونه از خاک (دو نمونه شاهد به عنوان اراضی طبیعی با پوسته های دست نخورده و دو نمونه از محل استخراج و برداشت سولفات سدیم به عنوان پوسته های تخریب شده در سه افق) بررسی و آزمایش دانه بندی شد. نتایج این پژوهش نشان داد پوسته های دست نخورده حاوی بیش از 60 درصد ذرات بزرگ تر از 2000 میکرون هستند. درنتیجه این خاک ها دربرابر فرسایش بادی آسیب پذیر نیستند؛ در حالی که درصد این ذرات در پوسته های به هم ریخته به کمتر از 40 می رسد که به طور چشمگیری مقاومت برشی آنها را کاهش می دهد؛ از طرفی ازدست دادن این پوسته ضمن کاهش عمل حفاظت کنندگی پوسته، رسوبات ریزدانه زیر سطحی را در معرض فرسایش بادی قرار می دهد که حاوی بیش از 70 درصد ذرات آسیب پذیرند. نتایج نشان داد برداشت و استخراج سولفات سدیم در منطقه باعث فرسایش باد حدود 5 برابر بیشتر از زمان حفظ خاک با پوسته می شود.

    کلیدواژگان: سولفات سدیم، فرسایش بادی، پوسته های تبخیری، دانهبندی، حفاظت خاک
  • مریم آزموده* صفحات 67-80

    ارتباط انسان و طبیعت و اهمیت بهره گیری از این ارتباط در محیط شهری، یکی از مسایلی است که همواره توجه برنامه ریزان حوزه فضای شهری را جلب کرده است؛ اما چندی است که انسان با ایجاد تغییرات در شهرها این تعامل حیاتی را به خطر انداخته است. یکی از عوامل موثر در این زمینه، احساس رضایتمندی انسان از شرایط حرارتی است. آسایش حرارتی در فضای باز علاوه بر شرایط اقلیمی، متاثر از محیط مصنوع پیرامون، پوشش های به کاررفته در زمین، تبخیر گیاهان و سایر عوامل موجود در سایت است. در این پژوهش از میان راه هایی که برای ارتقای آسایش حرارتی شهری وجود دارد، بر بهره گیری از گیاهان از طریق تعدیل دما و رطوبت تاکید می شود. در این پژوهش نخست تاثیر حضور گیاهان در قالب یک نمونه دیوار سبز به صورت میدانی ازنظر تاثیر بر دما و رطوبت نسبی تحلیل شد؛ سپس با استفاده از نرم افزار Envi-met یک بلوک شهری موجود با استقرار درختان فرضی و یک بلوک فرضی با اضافه کردن پوشش گیاهی شبیه سازی شد. براساس نتایج، دمای هوا در نقاط نزدیک به فضای استقرار گیاهان و در فاصله کمتر از 0.5 متر، حدود 0.5 درجه کمتر از سایر نقاط است؛ علاوه بر دما، رطوبت نسبی نیز در این محدوده بیشتر است که از برآیند تاثیر این دو عامل، آسایش حرارتی در میکرواقلیم های شهری اطراف گیاهان به ویژه در فصول گرم ارتقا خواهد یافت. بررسی انواع گیاهان نیز نشان داد تعدیل دما فارغ از نوع گیاه صورت خواهد گرفت.

    کلیدواژگان: گیاهان، آسایش حرارتی، فضای شهری، مطالعات میدانی، شبیه سازی
  • حسن لشکری*، مهناز جعفری، زینب محمدی صفحات 81-103

    بارش های زمستانه بخش جنوبی ایران به دلیل همزمانی با دوره کشت و تامین بخشی از آب مورد نیاز زراعت اهمیت ویژه ای دارد. بررسی بارش ماهانه 30ساله ایستگاه های جنوبی ایران در این پژوهش و سایر پژوهش های انجام شده نشان داد مقادیر بارش و تعداد سامانه های ورودی به این منطقه در ماه فوریه نسبت به ماه های قبل و بعد کاهش محسوسی دارد. برای علت یابی این پدیده پیش فرض های مختلفی بررسی شد. شارش رطوبتی از دریاهای گرم اطراف و رطوبت شارش شده روی منطقه، موقعیت مکانی واچرخند عربستان و موقعیت محور ناوه مدیترانه ای در کل دوره آماری (1986- 2017) و در سال های نمونه و موقعیت محور جت جنب حاره ای فقط در سال های نمونه، از گزینه های پیش فرض موثر بر تغییرات بارشی سه ماه بودند. نتایج این پژوهش نشان داد جابه جایی مکانی واچرخند عربستان به ویژه در لایه زیرین وردسپهر و جابه جایی نصف النهاری جت جنب حاره ای، از مهم ترین عوامل در کاهش یا افزایش بارش های سه ماه نسبت به همدیگر در جنوب و جنوب غرب ایران بوده است. جت جنب حاره ای که موثرترین جت در تشدید ناپایداری های همرفتی بخش جنوبی ایران است، در ماه فوریه از منطقه دور است و جابه جایی شمال سوی کاملا بارزی را نشان می دهد. همچنین سامانه های بارشی که از جنوب به منطقه وارد می شوند با جابه جایی شمالی تر و غرب سوتر، عموما به صورت سامانه های ادغامی از غرب به ایران وارد می شوند. پدیده دیگر، جابه جایی غرب سوتر و گسترش مداری تر واچرخند عربستان در ماه فوریه نسبت به دو ماه دیگر است. این الگوی گسترش واچرخند مانع جدی فرارفت رطوبت و گسترش سامانه سودانی روی منطقه است.

    کلیدواژگان: واچرخند عربستان، ناوه مدیترانه ای، جت جنب حاره ای، جنوب و جنوب غرب ایران
  • بهرام ایمانی* صفحات 105-128

    مدیریت مخاطرات محیطی ازجمله موضوعات محوری در دانش مخاطرات است و بر اقداماتی نظیر شناسایی، پهنه بندی و تفسیر نواحی مخاطره آمیز با هدف کاهش مخاطرات مبتنی است. تحقق اهداف و چشم اندازهای این دانش، نیازمند مجموعه اقدامات و مطالعات پیوسته ای در چهارچوب یک الگوی مدیریتی است که از گام های متعددی تشکیل شده است. به همین منظور نوشتار حاضر می کوشد با تدوین الگوی مدیریتی، مخاطرات طبیعی مسلط در منطقه رودبار را در هشت گام اصلی بررسی کند. در این زمینه در گام های نخستین، تعیین مبانی نظری مخاطرات و مخاطرات مسلط در منطقه مدنظر و طبقه بندی مخاطرات طبیعی انجام شد تا شرایط ارزیابی مخاطرات فراهم شود. در این مرحله به کمک روش تحلیل شبکه و تعیین معیارهای پیشنهادی در زمین لغزش، مسیر الگوی مدیریتی مخاطرات ادامه یافت. این معیارها در دو خوشه اصلی مخاطرات طبیعی و زیست محیطی طبقه بندی شد. در مرحله بعد با تهیه لایه های اطلاعاتی از عناصر مزبور و ارزش گذاری آنها، این لایه ها در محیط ARCGIS تحلیل و نقشه نهایی پهنه بندی زمین لغزش در محدوده شهری و روستایی رودبار با درجات خطر کم (4 درصد)، متوسط (71 درصد) و زیاد (25 درصد) تعیین شد. نتایج به دست آمده در گام بعدی با وضعیت نواحی شهری و روستایی ارزیابی شد تا زمینه های مولفه های ظرفیت جغرافیای طبیعی و انسانی کاهش مخاطرات مشخص شود. در انتها ضمن مطالعه تمهیدات سخت افزاری و نرم افزاری مورد نیاز دولت مرکزی، شیوه های بازنگری در خدمات رسانی، آستانه های خطر و شیوه های مقاوم سازی و آموزش ساکنان مطالعه شد.

    کلیدواژگان: مخاطرات طبیعی، الگوی مدیریتی، فرایند تحلیل شبکه، پایداری محیط، منطقه رودبار
  • حسین عساکره*، سید ابوالفضل مسعودیان، فاطمه ترکارانی صفحات 129-146

    تنوع عوامل مکانی (نظیر موقعیت جغرافیایی و ویژگی های توپوگرافیک) موجبات تنوع مکانی عناصر اقلیمی ازجمله بارش را فراهم کرده است. همراه با تغییرات زمانی بارش، عوامل مکانی نقش های مختلفی ایفا می کنند؛ از این رو برخلاف ثبات نسبی عوامل مکانی، می توان استنباط کرد که این عوامل در بستر تغییرات بارش نقش های مختلف ایفا می کنند. به منظور ردیابی نقش عوامل مکانی نظیر موقعیت (مختصات جغرافیایی) و عوامل توپوگرافیک (ارتفاع، شیب و جهت شیب) در بارش، از مدل شبکه عصبی مصنوعی استفاده شد. یافته های پژوهش حاضر نشان داد از دهه اول (1355- 1364) به سمت دهه چهارم (1385- 1394) میانگین بارش کشور کاهش زیادی داشته است. در این میان دهه دوم (1365- 1374) افزایش نسبتا زیادی را تجربه و روند عمومی کاهشی را مختل کرده است. میزان بارش حاصل از مدل های برازش یافته در هریک از دهه ها، الگوی تغییرات زمانی مکانی بارش واقعی را به خوبی بازتاب می دهد و توجیه می کند. براساس یافته های الگوی برازش یافته مشخص شد نقش بعضی از متغیرهای موقعیت جغرافیایی و عوامل توپوگرافیک از دهه ای به دهه دیگر بسیار تغییرپذیر بوده است و بعضی از متغیرها نقش های نسبتا ثابتی داشته اند. این امر گواهی بر این واقعیت است که تغییر کاهنده اثر یک متغیر با تغییر فزاینده اثر متغیرهای دیگر جبران می شود و نیز متناسب با تغییرات دهه ای بارش شکل می گیرد. در این میان نقش عرض جغرافیایی تغییرات زیادی داشته است. بیشترین و کمترین نقش این متغیر به ترتیب در دهه اول و دوم بوده است. در دو دهه انتهایی، تغییر همزمان نقش عرض جغرافیایی با تغییر میزان میانگین دهه ای بارش بسیار چشمگیرتر از دو دهه دیگر است. این واقعیت را می توان به تغییراتی نسبت داد که در مسیر چرخندها رخ داده است. این تغییر مسیر چرخندها در مطالعات پیشین بررسی و تایید شده است؛ علاوه بر این افزایش بارندگی در دهه دوم با ضریب های متفاوت از دهه های دیگر، نقش منحصربه فرد عوامل مکانی- توپوگرافیک را در دوره های پربارش و کم بارش نشان می دهد.

    کلیدواژگان: ایران، شبکه عصبی مصنوعی، وردایی دهه ای، تغییرپذیری بارش، متغیرهای مکانی، عوامل توپوگرافیک
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  • Atefeh Sedaghati, Mohammad Taghi Pirbabaei *, Farshad Noorian, Hamed Beyti Pages 1-30
    Introduction

    Urban housing planners, following the presentation of a suitable and desirable model of urban housing, have not considered a  model outside the category of consumer values and housing suppliers. They have always sought to identify values reflected in the consumer and producer preferences in the purchase and sale of a residential unit in an interactive way to take a more objective view of values by taking measures to use it in urban housing planning and design. The concept of ‘value’ in urban housing planning is a construct that, together with the essence of the society, can pave the way for the interaction of the benefits of the urban housing development model with the interests of their beneficiaries. As urbanization and urban planning issues have become more acute and studies have been conducted on urban housing development policies, aspects of their inefficiency such as creating price gaps between different types of housing in the city, non-compliance with ecological and climatic requirements, non-compliance with religious considerations, and religion (such as the discussion of aristocracy and respect for compatibility, proximity, neighborhoods, etc.), spatial separation of cities, social justice, etc. have become apparent. In Tabriz metropolis, with the increasing growth in the last decade, we are witnessing the development of various urban housing development programs and the growth of different types of residential neighborhoods, which in a similar way, has caused a high-value gap between different areas and neighborhoods of the city. The average house price in the metropolis of Tabriz is estimated to be very high and almost on par with the capital. In other words, the concept of value in housing planning in Tabriz has various features and a hidden market that can not reflect the pattern of an Islamic city. This has led to various different housing prices in the process of supply and demand.  

    Methodology

    The present study aimed to assess the concept of value in housing planning in the city of Tabriz based on Islamic culture and perspective as well as Islamic realism using Allameh Tabatabai's value theory and the research strategy of post-mining. Since many of the features explaining the value of urban housing are not directly traded in the market, the basics of the Hedonic model have been used to quantify values. The explanatory model in the City of Tabriz (using three samples: Rushdie, Ashkan, and Chamran housing complexes) was tested and analyzed by correlation and regression (linear and quasi-logarithmic) models. Given that the data of the study are both quantitative and qualitative, the analysis model is covariance analysis or ANCOVA. In order to perform correlation analysis, the Spearman coefficient was used for ranking data and the Pearson coefficient was used for distance data. To identify the variables regarding value urban housing, multivariate linear regression was used. Rushdie town was a well-planned example that covered both villas and apartments. Chamran complex was also a manifestation of the planned apartment complex. Ashkan neighborhood was considered as a guided neighbor (according to the detailed and comprehensive plan of cities).   

    Discussion

    The findings of the research showed that structural-physical and environmental categories related to the ‘access to land uses’ were most significant in explaining the variable ‘value of urban housing’ in Tabriz.  Furthermore, in well-planned ones, such as in the Rushdie complex, many of the criteria were not met. It should be noted that although the same variables were included in the model in all three samples, due to different responses and inhomogeneous housing conditions in the samples, different results were obtained in the samples, but the structure of the variables was the same. In fact, the observations can be explained by a common structure. It should be noted that   each sample, in terms of significant variables, by itself can not conceptually expand the structure of consumer and producer housing preferences. Allameh similarly believes that values have a fixed structure (innate tendency towards good and true Goodness and escape from wickedness) but they can accept different examples and the goodness of such examples is not absolute and definite. In line with the results, it should be added that the physical and structural features of a building and its environmental and local location are included in the calculations as ‘variable’. The results depend on the type of the selected house (apartment/villa), the type of selected area, etc., which could also be affected by the time period and spatial scale. However, these variables are pre-designed and their repetition and frequency do not necessarily indicate their superior preference. For example, some previous policies of urban housing planners and city managers have created values ​​in cities that are not necessarily considered good. The value in the identified model does not necessarily have a positive semantic burden that should be considered as a credit structure in the housing planning process from now on. But these values, in fact, in a way summarize the cause-and-effect relationship in the city system. It is the urbanization and identification of existing disciplines that, as mentioned, are not necessarily considered valuable. The repetition of values ​​and obtaining the coefficient in the developed Hedonic model show that these variables play a role in the existing structure of Tabriz housing planning and have formed some patterns.  

    Conclusion

    Value is a cultural category and the housing planning derived from values is in fact linking urban housing development programs and policies with the culture that governs our society. From this perspective, in the process of housing planning, it is necessary to do more research reflection on the issue of its value and meaning in the society and from the perspective of expectations and preferences of individuals and beneficiarieswhich could  lead to more achievable policies. Considering that the housing development model is context- and value-driven in a given society and that value is a cultural phenomenon, it is necessary to identify community values first and the plan for urban housing using the values as a guide.  Islamic cities can become representatives of Islamic culture. According to the findings, in the city of Tabriz, it can be concluded that despite many similarities in the content of values, in terms of the value system, differences according to economic, environmental, social conditions, heterogeneous tendencies, and expectations of residents  exist. Therefore, a single version cannot be developed to explain the concept of value in cities. People are more likely to choose areas that are closer to their expectations. However, it depends on  their purchasing power; therefore,  customer's preferences for housing characteristics (values) could  be reflected in the spatial pattern of price and value of urban housing. The most important suggestion of studies based on the totality of what was discussed is that in the process of urban housing planning, before planning and formulating any urban development plan, a proper understanding of the values ​​governing the society should be reflected on and the values ​​should be more tangible. In this way, urban housing planning is looked at something more than   mere housing development; instead,  housing and its surroundings, along with the expectations and values ​​of residents, are seen as an interactive set.  

    Keywords: the Concept of Value, Planning for Urban Housing, Tabriz city, Islamic Perspective
  • Samane Miralijani, Mohammadamin Khorasani * Pages 31-46

    Quality of life findings can be used to identify past strategy policies and design future policies. As such, the issue of quality of urban and rural life in recent decades has become one of the most important issues in Iran, so  numerous seminars, conferences, and articles have been held and written to examine the quality of life. In recent years, experts have tried to look at this issue in Iran from a scientific point of view. The present study was conducted with the aim of analyzing the scientific research articles written on the quality of rural life in Iran during the years 2011 to 2019. The results of the study show that in terms of the gender status of the authors during the 9 years studied, out of 271 authors, 210 (77%) of them were men while 61 of them were women. Regarding the expertise of the authors, which was divided into 9 categories, the most specialized field was rural planning with 61.62% and urban planning with 9.23% while other fields had a small share. The organizational affiliation of  authors was classified into six groups including State Universities, the Islamic Azad University, Payame Noor University,  non-profit organizations, government institutions, and other institutions. Government institutions with a frequency of 233 (85.98%) had the highest level of organizational dependence suggesting a significant gap between the state universities and other institutions. Also, the number of authors and their articles showed that the highest number of authors (79.29%) have been co-outhors of one  article. In other words, about three-quarters of the authors were present in only one article, which indicated the relatively low diversity of names in the published articles. To determine thematic trends and prevent dispersion, the topics presented in 20 categories were classified as follows. One of the most important topics for writers in the field of rural studies was the evaluation of the quality of life and its indicators with the frequency of 31 (32.63%) with the highest frequency among other topics. Other topics of interest to authors included dimensions, components, and levels of quality of life and the effects of the master plan on quality of life (5.26%); social dimensions of quality of life (7.37%), the spatial distribution of quality of life, the role of credits and targeted subsidies on quality of life, employment, income, and quality of life and tourism and quality of life (6.32%); factors affecting the quality of life and quality of life and housing (4.21%); satisfaction with the quality of life and the role of small towns and industrial towns on quality of life 3.16%; and agriculture and the quality of life (2.11%). Other thematic trends (1.05%), recived the least attention. Also, in the field of distribution of provinces studied by the authors, Kermanshah and Khorasan Razavi provinces with 10 articles were in the first rank,Fars province with 9 articles in the second rank, and Zanjan province with 8 articles in the third rank. Golestan, Sistan and Baluchestan, and Kurdistan were in the fourth rank with 7 articles, and Lorestan and Kohgiluyeh and Boyer-Ahmad provinces were in the fifth place with 5 articles and other provinces were in the next positions. The results suggest that the discussion of rural studies, which has been less discussed so far, is important and should be given more attention to provide other researchers with such studies to provide a context for the development of villages. Keywords: Quality of Life, Quality of Rural Life, Scientific Research Article, Content Analysis. 

    Keywords: Quality of Life, Quality of Rural Life, scientific research article, content analysis
  • Majid Karimpourreihan, Naser Mashhadi *, Azam Beigi Pages 47-66
    Introduction

    Lowlands, playas, and downstream portions  of rivers in desert areas contain vast reserves of fine-grained sediments, such as silt and clay, as well as soluble materials including a variety of salts. Surfaces created by the combination of these materials can become periodically susceptible to wind erosion. Thus,they are considered to be major dust sources on a global scale.Depending on the spatio-temperial distribution and composition of salts and fine materials, some proportions of these areas areusually either covered by an evaporite salt crust or disperedsoil.Crust is a relatively thin consolidated soil surface layer or seal that is more compact and cohesive than the material immediately below it. When crusts are formed, particles are bound together and become less susceptible to abrasion by blowing soils compared tothe less stable material below the crust. Both crusted surfaces and dispersed soils are morphologically and geochemically dynamic and can respond rapidly to changes in the local environmental conditions.These changes can be natural, such as the frequencies of surfacedrying and flooding by rainwater or the changing groundwater levels, or can be the result ofanthroponic activitiesproviding salt resources for economic use.Over time, the continued operations of both mechanical and chemical processes on lowland surfaces ultimately lead to the decay of salt crust integrity.Crusts usually provide a protectionagainstan underlying ‘fluffy’ layer of sedimentsrepresentingas salty sediments of dust-size fractions with notably low bulk densities.Wind erosion activity occurs particularly when the crust is disturbed or broken by different activities, such as  salt extraction or vehicular traffic flow.In all desert areas of Iransodium sulphate (Na2SO4) salts are deposited based on humidityand temperatureconditions, as well as groundwater levels and degrees of salt solubility (concentration). These areas usually occur between downstream of covered pediments and upstream of playas.Traditionally, these areas arevalued forsodium sulphate salt extraction,whichcontributes to the economy of the local population in several ways.The study area  was the lowland area of Ivanki, which was one of the areas undergoing wide sodium sulfate extraction. According to the residents, this area providedsand sources forwind erosion and air pollution.It was often a source of emission made by the existingmaterials not only because of wind erosion, but also due tosodium sulfate extraction.This paper investigated the effect of sodium sulfate extraction on creating or exacerbating wind erosion through a collection of sediment samples taken at the sodium sulfate extraction site and their grain-size testing.

    Methodology

    The sodium sulfate extraction sites were identified based on local information and interpretation of satellite images. The areawas located in the southwest of Eyvankey City between covered pediments and internetworks of playa.It occupied an area of approximately 5000 ha. The sampling points were identified based on geological and geomorphological studies.SThe sampling wascarried out at the summer season.  4Four sites were considered for sampling;two sites asthe control sites and two sites forsodium sulfate extraction. In the control sites, only one sample was taken from the topsoil (natural land) without manipulation and extraction, whilethe samples in the other two sites were taken from 3horizons: a) soil samples fromthe degraded surfaces; b) samplesoriginated fromthe extraction horizon; and c) samples from the lower layers (without manipulation and extraction).Thus, 8 samples were totally collected.The obtained samples were granulated by the common dry-sieving method.Granulometric statistical analysis wasdone for each sample by using GRADISTAT software. 

    Discussion

    According to the ambrothermic diagram, drought conditions prevailed in the region for about 7 months of the year. This drought couldthe aggravating wind erosionparameters, such as soil moisture and vegetation cover. The warm period corresponded to the warm seasons (spring and summer).Anemometer measurements showed that the study area was affected by erosive and strong winds blowing from the north, northwest, and east.Land cover studies revealedthat more than 60% of the soil surface in the control samples was preserved by the crust with particles larger than 2000 microns. However, after crust destruction for sodium sulfateextraction, the effect of crust cover was less than 45%. In other words, the soil surface lost 25% resistance to wind erosion.In the process of sodium sulfate extraction, the soil under the crust, which contained soil particles, along with a significant amount of powdered sodium sulfate particles, was exposed to wind erosion.Our studyshowed that the frequency percentage of vulnerable particles changedfrom about 10% in the surface layer in the control samples to about 50% in the middle and lower layers of the extracted areas. This meant that the region was about 5 times more sensitive to wind erosion.Studies on the statistical parameters of the samples demonstratedthat the average particle diameters significantly and regularly changed from very coarse sands (surface layers of the control samples or natural lands) to coarse sands (degraded surface layers),fine sands (middle layers), and finally very fine sands (bottom layers), which indicatedincreasedsensitivity to the wind erosion process from the surface layer (crust) to the bottom layer. 

    Conclusion

    In this research, field observations, mechanical analysis of soil particle granulation, and investigation of wind characteristics showed that a very high potential ofdust emission from degraded crusts triggered by open extraction. Spatial changes and displacement of removal areas caused bysodium sulfate reduction duringthe extraction periodled tofurther environmental destruction and wind erosion intensification. The results revealeda significant complexity in the relationships ofthe flux of dust emitted from thecrust degraded by sodium sulfate extraction and natural surface crust withthe threshold wind speed required for wind erosion, which suggests furtherresearch to be conducted in this regard in the future. Keywords:sodium sulphate, wind erosion, evaporative crust, granulometry, soil conservation .

    Keywords: sodium sulphate, Wind Erosion, evaporative crust, granulometry, Soil Conservation
  • Maryam Azmoodeh * Pages 67-80

    The relationship between man and nature and its importance in the urban environment is one of the issues considered by theorists and planners in the field of urban space for a long time. However, human beings as the basis for this relationship have  jeopardizing this vital interaction by making changes in cities for some time now. One of the significanr in human communication and the redidence in cities is his satisfaction by climate conditions. The outdoor thermal comfort is affected by the built environment, land cover, plant evapotranspiration, and other factors present at the site. In this study, among the ways of promoting thermal comfort in urban space, the use of plants is focused on. In this article, the effects of plants on temperature and relative humidity were firstly analyzed in a case study. Then, using Envi-met software, an existing urban block was simulated by placing hypothetical trees and another hypothetical block was simulated as well. According to the results, the air temperature in the places, which were very close to the nearly 50-cm plants, was obtained to be almost 0.5◦C lower than other places. In addition, the relative humidity within the studied limits was higher. Therefore, the effects of these two factors on improving the thermal comfort of urban microclimates, especially in hot seasons, could be well evidenced. The assessment of different types of plants also showed that the temperature adjustment could be achieved regardless of plant type.

    Keywords: plant, Thermal Comfort, Urban Space, field study, Simulation
  • H. Lashkari *, Mahnaz Jafari, Zainab Mohammadi Pages 81-103
    Introduction

    Precipitation is one of the most important and complex climatic elements. This vital element, on which the lives of living organisms and fauna depend, has highly variable temporal and spatial distributions in the world. While limited areas of the planet have an excess precipitation, a large part of it is facing the shortage of this vital element. Therefore, its spatial distribution on the Earth is not at all satisfactory to the inhabitants. In the subtropical regions, this limitation is of great significance. For this reason, officials and users are so willing to receive more precipitation during the cooler months and minimize water loss from evaporation and transpiration. Winter precipitation can be very useful and effective in these areas. Several studies conducted on the trend of monthly precipitations in the cold periods of the year in the southern regions of Iran have found significant decreases in February precipitations compared to those of the two previous and following months recorded at most of the south and southwest stations. Considering that southern regions are among the few regions in Iran where the precipitation periods correspond to the cultivation periods, this problem was studied and analyzed as the main issue of this research. 

    Methodology

    As stated, the purpose of this study was to identify the synoptic factors of decreasing precipitations in the southern half of Iran in February compared to March. To find the cause of this phenomenon, first, the data provided by the representative stations during the statistical period of 1986-2017 were selected. The ERA-Interim data from the European Center for Medium-Range Weather Forecast (ECMWF) with the spatial resolution of 0.5×0.5 degrees were used to investigate the synoptic patterns. For synoptic analysis, several samples were chosen from the statistical period. Moreover, various assumptions were examined to determine the cause of this phenomenon.To study moisture changes in February and March, changes in the moisture transfer from the Arabian and Oman Seas with negative values for the outflow of moisture fluxes and the relevant changes from the south and southwest regions of Iran with positive values of the inflow of moisture fluxes in the lower atmosphere were calculated. Displacements and fluctuations in pressure patterns and systems lead to significant changes in the meteorological phenomena. Therefore, due to the very important role of the Arabian subtropical high-pressure system in transferring moisture from the Arabian and Oman Seas to the Arabian Peninsula and towards Sudan low-pressure system, the locations and displacements of the high-pressure cores were extracted at the level of 850 hPa. Also, due to the more important role of Mediterranean troughs in the moisture advection transfer from these warm seas in the study area, their locations and depths were extracted from the selected samples at the level of 700 hPa in February and March within the statistical period. Subtropical jets play a crucial role in the dynamic structure of Sudan low-pressure precipitation systems. Therefore, another component studied in this research was the changes in the positions and structures of subtropical jets throughout the selected samples at the levels of 300 and 250 hPa in February and March. 

    Discussion

    Winter precipitation in the southern part of Iran is of special importance due to its coincidence with the cultivation period and supplying part of the water needed for agriculture. The results obtained by Mohammadi & Lashkari (2020) and Esfandiari & Lashkari (2020) showed that the amount of precipitation and number of the input systems in this region in February compared to the months before and after it had significantly decreased.  Evaluation of moisture fluxA comparison of the amount of moisture released from the Arabian Sea with the moisture entering the region revealed the very significant difference of February precipitation, while the difference was very small in March, which was perfectly compatible in many cases. Hence, there must have been barriers to the transfer of moisture from the surrounding seas into the region in February.  Evaluation of the position of Saudi ArabiaIn terms of the latitude, there was no significant difference in the positions of Arabian subtropical high-pressure systems between the two months. However, the oscillations of their cores were much more intense in terms of longitude. In some years, the cores had moved up to about 70 degrees east longitude. In March, the displacements of the cores were quite noticeable compared to those of the other two months. During this month, most of the cores were located in Oman and its eastern coast. An interesting phenomenon was that the high-pressure cores of all the sample years were located in Oman and sometimes in the waters of the Arabian Sea at a distance from the coast. 3. Evaluation of the position of Mediterranean troughsThe axes of Mediterranean troughs did not show a significant difference in both the depth and longitudinal position. In this way, the troughs were in a good position in terms of transferring instabilities to the region every two months. They also had a suitable depth for transferring and injecting sufficient vorticities into the heating systems of this region.  Evaluation of the position of the subtropical jetsThe longitudinal and latitudinal positions of the subtropical jets were very different in February and March. Three features could be seen in the axes of the February jets. First, the jets had significant northward displacements in all the selected samples and thus, the jets located at this latitude did not create suitable dynamic conditions for the instabilities of southern and southwestern Iran. Second, the longitudinal axes of the jets in this month had been shortened. Most of the jets were coming from the east and center of Egypt. Third, most of the axes tended to be orbital. This feature caused the jets not to have a suitable vorticity.The expansion patterns of the jets in March were completely different from those of February. During this month, the subtropical jets had relocated to lower latitudes and were distributed between northwestern Iran and southern Saudi Arabia. Therefore, the southern and southwestern parts were exposed to the instabilities caused by the subtropical jets. Another notable change was in the lengths of the subtropical jets. Most of the jets had started in the southwest-northeast direction at a distance from behind Egypt and over Chad and even farther back of it. The jets had a more meridional pattern in March compared to February. 

    Conclusion

    The main purpose of this study was to find the cause of reduced precipitations in February compared to March in the southern regions of Iran. The results of this research revealed that the two factors of spatial displacement of the Arabian subtropical high-pressure system, especially at the level of 850 hPa and the lower layer of the atmosphere, and the displacements of subtropical jets in the northern and southern parts were the most important factors for lowering precipitations in February compared to the other months of the cold period of the year in the south of Iran. The subtropical jets showed a noticeable northward movements in February. This pattern of establishment had caused precipitation systems to enter the region from the south, move towards higher northern latitudes and western longitudes, and frequently enter Iran from the west in the form of integrated systems. At the same time, this had caused the Arabian subtropical high-pressure system to move westward and settle on the lands of eastern Saudi Arabia, preventing the entry of Sudanese systems into southern Iran and moving westward. 

    Keywords: precipitation anomaly, Moisture flux, Arabian subtropical high-pressure system, Mediterranean Trough, Subtropical jet, South, Southwest of Iran
  • Bahram Imani * Pages 105-128
    Introduction 

    One of the main tasks of hazard knowledge is to study the situation and value of the human environment that is vulnerable to all types of natural and human hazards. Hazards in the environment are caused by the instability of the characteristics of natural environment (land surface, biological phenomenon, climate) and human environment (security, technology, etc.), which appear as dangerous events due to human interventions and infrastructures caused by urban-rural developments. In general, it is necessary to take several steps towards designing management models to achieve and formally apply the perspectives of risk knowledge and reduce and manage environmental risks. Establishment of a relationship between the various components of environmental hazards requires the researchers to formulate hazard trends through a model so that this complex and multidimensional process can be easily understood and implemented. This pattern would be a theoretical and simplified representation of the real world. For researchers, who try to understand and apply the principles of risk knowledge in urban and rural settings, this model is a theoretical tool consisting of concepts, hypotheses, and indicators that facilitate selection and collection of the information needed to achieve the basic goals. This research tried to study the risk of landslides in Rudbar in the form of a management model, including risk identification, risk and hazard assessment, zoning, etc., so as to manage and alleviate hazards in the urban and rural areas of Rudbar region. At the same time, the roles of central government and local management in lowering risks were evaluated by reviewing the required measures. The related institutions have a pivotal position in the development and risk management of this area and are capable of taking executive measures to reduce risks and vulnerability within their frameworks, provide sustainability of urban and rural settlements against geomorphological hazards, highlight the challenges ahead, especially from a managerial perspective, and define and present solutions in this regard. 

    Research Methodology

    In terms of methodology, this paper was based on a quantitative method (assessment and zoning of landslide hazards using a network-derived decision model) and a qualitative method (development of an environmental risk management model with an emphasis on sustainability of urban and rural areas). In the first part, a library method, including a review of theoretical studies of hazard knowledge, landslide analysis, drawing and analysis of related maps, etc., was utilized to develop a management model for environmental hazards. In the second part, by combining the library and field methods, i.e., scientific observation and regional study, several interviews were done with the executive community (governorate officials and district municipality), scientific community (environmental risk experts and urban and rural planners), and local community (natives of Rudbar and adjacent villages) to formulate management components and analyze the current situation for developing a management model of environmental hazards in the study area. The landslide risk zoning process was designed and evaluated within the framework of a network-derived decision model. Assessing and interpreting risk levels via a management model are very important since development of a model highly depends on the evaluation. If the prevailing risk situation in a region is favorable, its management issue may either be eliminated or appear different from the expected disastrous conditions.

     Findings

    In general, environmental risk management requires interaction of geographical sciences with each other. Therefore, in the formulation and study of environmental risk management models in urban and rural areas, it is necessary to study geographical and other related sciences along with the knowledge of urban-rural planning and applied geomorphology. In this research, the position of each of them in the implementation steps of the environmental risk management modeling of Rudbar region was addressed. For formulating a conceptual model and routing the sustainable management of landslide hazards, various steps must be taken based on the mutual and effective roles of the academic community or researchers, the executive community or decision makers, and the indigenous community or local people with regard to demand resilience. A wide-range geosystem, including coastal and wind geosystems, etc., is associated with different geomorphic actions and reactions and therefore, each management style would be unique in nature. For example, the issues of resilience, prevention, risk preparedness, and special management capacity would generally require special areas. In this regard, the present research as a case study examined the most susceptible management model in the form of risk knowledge in 9 main steps (Fig. 3) through the implementation process. According to this proposed model, the first step began with the definitions, goals, and perspectives of risk and risk knowledge and the final step ended with a review of the measures taken with the objectives in mind. The scientific support of environmental risk management in the forms of a study and implementation requires a combination of theoretical, practical, technical, and executive studies. 

    Conclusion

    Hazard knowledge is a broad and continuous set of theoretical and field studies of risk management and executive measures. The goals and prospects of this knowledge can be achieved to reduce and manage environmental risks by identifying and taking various steps in line with management models. Therefore, in this paper, an attempt was made to develop a natural hazard management model, especially for landslides, that controls urban and rural areas. In this regard, after applying the theoretical foundations of hazardology, the natural hazards were classified by determining the dominant hazards in the study area with the help of theoretical and field studies. These hazards were then analyzed and zoned. At this stage, by determining the effective elements in the occurrence of landslide risks, including slope, slope direction, lithology, land use, average annual rainfall, distance from faults, waterways, and residential centers, and weighting these elements in relation to each other,  each element was zoned based on the experts’ opinions, study background, and field visits by using the network analysis method to assess the performance of urban landslide risks. The results showed that among the studied variables, the two factors of slope and lithology had the largest effective coefficients in the occurrence of landslide risk in Rudbar region. Only 22% of the areas with a slope class of less than 20% was within the specified range. This is while the appropriate slope range for urban construction based on sustainable urban planning standards is between 8 and 15 degrees. Among other hazardous elements playing a role in the urban landslide occurrence of Rudbar region, the lithological factor was shown to be vulnerable in terms of mass. In this region, the predominant lithological structure consisted of periodic Eocene volcanic rocks, sandstones alternating between shale layers, and Quaternary alluviums that were sensitive to human activities, such as construction of settlements, intercommunication routes, etc. In the next step, the results were evaluated and interpreted based on the status of urban and rural settlements so as to explore the areas of natural and human geographical capacities and components of risk reduction, while studying the hardware and software measures required by the central government of Gilan Province and Rudbar Municipality and reviewing services before and after the occurrence of danger, risk thresholds and resilience, and the residents’ levels of education. Finally, after achieving the knowledge of risks, the environmental risks were comparatively studied to properly manage them. Keywords: natural hazards, management model, network analysis process, environmental sustainability, Rudbar region .

    Keywords: Natural Hazards, Management model, Network Analysis Process, Environmental Sustainability, Rudbar region
  • Hossein Asakereh *, Seyed Abolfazl Masoodian, Fatemeh Tarkarani Pages 129-146
    Introduction

    Some mechanisms of climate change, particularly changes in precipitation, are the result of changes in local mechanisms, while some others are caused by the interaction of events on larger scales, e.g., regional, synoptic, hemispherical, or planetary scales. However, in all these changes, the reactions of spatial factors like geographical coordinates (latitude and longitude) and topographic features, including altitude, terrain slope, and terrain aspect, on a local scale can be a proper signal of large-scale changes. In particular, numerous studies have shown that spatial variations, as well as temporal variability of precipitation, are in relation with spatial coordinates (longitude and latitude) and topography (altitude, terrain slope, and terrain aspect). Nevertheless, the fact that the temporal variation of precipitation is in relation with the roles of spatial factors has been neglected.Using the Artificial Neural Network (ANN) technique, the present study aimed to provide inferences about the decadal changes in the overt and covert links of spatial factors with the precipitation climatology of Iran. Thus, using the national network data (Asfazari), 3rd version, the spatial distributions of precipitation for the last four decades were compared based on spatial factors. Also, an attempt was made to show the decadal variation of precipitation in Iran in relation to spatial factors, which could serve as an index of climate change as an essential field of research on precipitation. 

    Data and Methodology

    Two datasets were employed to conduct this investigation; the 3rd version of Asfazari Precipitation Dataset and the data of a Digital Elevation Model (DEM) related to Iran. The first dataset with the dimensions of 16801×205×167 and a resolution of 10 km was applied to study the temporal and spatial behaviors of precipitation within Iranian borders. The second dataset with a resolution of 10 km belonged to the US Geological Survey produced via ASTER satellite imagery with a global coverage.Based on the two above-mentioned datasets, the following steps and methods were taken and adopted to conduct the current study:1- The average precipitation for the whole period (1969-2015) was calculated and its spatial relationships were examined. To investigate the variability of decadal precipitation, the average precipitation for each decade up to the decade of 2006-2015 was measured. Thus, the first 6 years (1969-1975) did not fit into the study decades to provide a comparison. Accordingly, the spatial characteristics of precipitation in Iran during the four decades of 1976-1985, 1986-1995, 1996-2005, and 2006-2015 were studied.Precipitation is considered as one of the elements, phenomena, and climatic processes, as well as an important indicator, in climate change tracking. One of the notable features of precipitation is its strong and often nonlinear relationship with geographical coordinates (latitude and longitude) and topographic factors (altitude, slope, and slope direction). There are several ways to study this relationship. In this regard, we can refer to regression methods, control methods, ANN methods, etc. In recent years, the use of regression techniques (for example, Singh et al., 1995; Glazin, 1997; Alijani, 1373; Ghayyur and Masoudian, 1375; Mojarad and Moradifar, 1382; Asakereh, 1384; Razi'i and Azizi, 1387) has been in focus.Modeling the time series of climate like precipitation and chaotic spatial relationships of such nonlinear series are difficult and complex task due to atmospheric dynamics and its nonlinear relationships with spatial variables and since temporal change (variability) of precipitation in a continuous and chaotic system reflects a complex and nonlinear atmospheric behavior in the "geographical space". The spatial analysis showed that the relationships between precipitation and spatial factors had undergone a change on the tempo-spatial scale. Accordingly, complex algorithms, such as ANN methods, were more suitable for modeling these chaotic time series in a broad space like Iran.To study the characteristics of precipitation in Iran and compare the spatial relationships of precipitation in the current research, the spatial distribution of precipitation on the decadal scale and the decadal variability of precipitation were first investigated. Based on the selected spatial-topographic factors in all 16203 cells on the map of Iran as the ANN inputs, a model could be extracted to better fit the data. In this paper, the precipitation in Iran was regarded as the target variable to be compared with the model outputs. 

    Results and discussion

    General characteristics of annual rainfallThe spatial average of precipitation was about 250.5 mm. There was a very large spatial difference of precipitation in Iran. The spatial variability of precipitation was estimated based on geographic coordinates and topographic variables by using the ANN technique. Although the model’s error rate (88809.3) was noticeable, the correlation coefficient (0.95) showed that the estimated spatial distribution pattern of precipitation and the spatial distribution of real precipitation were very similar (90%). The absolute values of the model’s coefficients revealed that longitude, latitude, and altitude played the most important roles, respectively. The terrain aspect played the least important role in justifying precipitation. Decadal changes of precipitationThe average precipitation in the country demonstrated a significant decrease from 268.1 to 220.3 mm from the first to the fourth decade. Nonetheless, the second decade had experienced a relatively significant increase and thus disrupted the general downward trend. The average precipitation anomaly was negative in the last two decades as well. This was evidence of the impact of the decreasing trend of precipitation in all regions of the country. Consequently, in the last two decades, 76.1 and 81% of Iran’s territory had received less precipitation than the long-term average precipitation between 1969 and 2015, respectively. The amounts of precipitation in the models fitted to each decade were compatible with the actual precipitation amounts. Therefore, the role of spatial factors in estimating rainfall had an acceptable capability.Decadal changes in the effects of spatial factorsAssessment of latitude coefficients revealed that both the pattern and coefficient values ​​were corresponding to the first, third, and fourth decades. It seemed that the negative values of latitude increased towards the last decade. For the second decade, which was associated with a relative enhancement in rainfall, the coefficients were different from those of the other decades. In this decade, coefficient variability was higher than those of the other decades. The average longitude coefficients of 10 neurons for the four studied decades were 1.76, 29.35, 0.91, and -1.19, respectively. The average altitude coefficients of neurons for these decades were about -2.87, -7.3, 0.1, and 3.75, respectively. Also, the average slope coefficients for the decades were almost similar to those of the altitude pattern (-2.29, 29.91, 0.3, and -0.22, respectively). However, the degrees of influence (coefficient values) and their signs were highly different for these two factors. Finally, the average coefficients for slope for the mentioned decades were about -0.71, 31.18, 0.34, and -2.83, respectively.

     Conclusion

    In this investigation, the diversity of spatial factors, such as geographical coordinates and topographic features, were found to have led to the spatial diversity of climatic elements like precipitation.  In association with the temporal changes of precipitation, spatial factors played different roles in the process. Therefore, despite the relative stability of spatial factors, it could be inferred that these factors played different roles in the context of precipitation changes. To track the roles of geographical coordinates and topographic factors, i.e., altitude, terrain slope, and terrain aspect, in precipitation, the Artificial Neural Network (ANN) model was utilized. The research findings could be presented in two categories as follows

    Keywords: Iran, Artificial Neural Network (ANN), Decadal Variation, Precipitation Variability, spatial variable, topographic factor