بررسی تأثیر پوشش‌گیاهی بر آسایش حرارتی در اقلیم گرم و خشک (در مقیاس خرد-محله مسکونی خلدبرین- شیراز)

دوره 23، شماره 158
مرداد 1405
صفحه 19-26

نوع مقاله : مقالۀ پژوهشی

نویسندگان

1 گروه معماری ، دانشکدۀ مهندسی معماری و شهرسازی ، دانشگاه تربیت دبیر شهید رجایی، تهران، ایران

2 گروه برنامه‌ریزی و طراحی شهری و منطقه‌ای، دانشکدۀ معماری و شهرسازی ، دانشگاه شهید بهشتی، تهران، ایران

3 گروه معماری، دانشکدۀ هنر و معماری، دانشگاه بین المللی امام خمینی (ره) قزوین، قزوین، ایران

چکیده
بیان مسئله: شهرنشینی و توسعۀ کالبدی بی‌رویه شهرها بدون توجه به پیامدهای اقلیمی، سبب افزایش دمای محیط و به دنبال آن، کاهش میزان آسایش حرارتی و کیفیت زیستی شهروندان در فضاهای بیرونی در مناطق گرم و خشک شده است. اگرچه استفاده از پوشش‌گیاهی می‌تواند از طریق سایه‌اندازی و تعدیل تابش سبب آسایش حرارتی بیشترشود، اما اثربخشی این راهکار در مقیاس خرد (مانند گذرهای مسکونی) همچنان محل تردید و بررسی بیشتر است.
هدف پژوهش: این پژوهش به ارزیابی نقش پوشش‌گیاهی در تعدیل آسایش حرارتی در مقیاس خرد در فضای شهری در اقلیم گرم و خشک می‌پردازد.
روش پژوهش: دو کوچه با ویژگی‌های کالبدی مشابه ولی پوشش‌گیاهی متفاوت در محلۀ خلدبرین شیراز انتخاب و داده‌های میدانی شامل دمای هوای و رطوبت نسبی در ساعات اوج گرما برداشت شد. این داده‌ها پس از شبیه‌سازی محیط مورد بررسی در نرم‌افزار انویمت‌ لحاظ شده و با شاخص PMV در نرم‌افزار Bio-MET تحلیل شدند.
نتیجه‌گیری: نتایج نشان داد که اختلاف دما در بهترین حالت حدود دو درجه سانتی‌گراد بوده و شاخص آسایش حرارتی همچنان در وضعیت «خیلی گرم» باقی مانده است. به‌رغم اثر نسبی پوشش‌گیاهی، این میزان تغییر به‌تنهایی برای تأمین آسایش حرارتی کفایت نمی‌کند. یافته‌ها نشان دادند که نوع و فرم تاج درختان نقش مهمی در بهبود شرایط حرارتی دارند. این پژوهش تأکید می‌کند که طراحی مؤثر فضاهای سبز با درختان دارای تاج گسترده، مؤثرتر از کاشت صرف درختان کوتاه‌تاج خواهد بود.

کلیدواژه‌ها

موضوعات

عنوان مقاله English

Investigating the Impact of Vegetation on Thermal Comfort in a Hot and Arid Climate (A Micro-Scale Study of Kholdebarin Residential Neighborhood, Shiraz, Iran)

نویسندگان English

Fatemeh Minabian 1
Nazanin Fakhfoori 2
Mohammadreza Mehrabani Golzar 3
1 Department of Architecture, Faculty of Architectural Engineering and Urban Planning, Shahid Rajaee Teacher Training University, Tehran, Iran
2 Department of Urban and Regional Design and Planning, Faculty of Architecture and Urban Planning, Shahid Beheshti University of Tehran, Tehran, Iran
3 Department of Architecture, Faculty of Art and Architecture, Imam Khomeini International University of Qazvin, Qazvin, Iran
چکیده English

Problem statement: Urbanization and uncontrolled physical expansion of cities, without consideration of climatic consequences, have led to rising ambient temperatures and a subsequent decline in thermal comfort and quality of life for residents in outdoor spaces within hot and arid climates. Although vegetation can enhance thermal comfort through shading and radiation mitigation, the effectiveness of this strategy at the microscale, such as in residential alleys, remains uncertain and warrants further investigation.
Research objective: This study evaluates the role of vegetation in moderating thermal comfort at the microscale in urban spaces within a hot and arid climate.
Research method: Two alleys with similar physical characteristics but different vegetation conditions in the Kholdebarin neighborhood of Shiraz, Iran, were selected. Field data, including air temperature and relative humidity, were collected during peak heat hours. Following the simulation of the study environment in ENVI-met, the data were analyzed using the PMV index in Bio-MET.
Conclusion: Results showed that the maximum temperature difference was approximately 2°C, while the PMV index remained in the “very hot” range. Despite the relative effect of vegetation, this degree of change is insufficient to provide thermal comfort. The findings demonstrate that tree species and canopy form play a significant role in improving thermal conditions. This study emphasizes that effective green space design incorporating trees with wide canopies is more impactful than simply planting trees with limited canopy cover.

کلیدواژه‌ها English

  • Thermal comfort
  • Hot and arid climate
  • Vegetation
  • Microclimate simulation.
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