تبیین شاخص‌ها، کیفیت‌های فرم شهری و توزیع فضایی آنها در سطح محلات کلان‌شهر تهران

مطالعات پیشین فرم شهری بر اساس کیفیت‌های مختلف فرم شهری، شاخص‌های مختلف مرتبط به آن را سنجیده‌اند. لذا سوالی که مطرح می‌شود این است که چگونه می‌توان بر اساس شاخص‌های قابل سنجش فرم شهری در سطح محلات، کیفیت‌های فرم شهری را در این مقیاس ارائه کرد. لذا این مقاله با هدف یافتن شاخص‌های اصلی معرف فرم شهری و تبیین کیفیت‌های فرم شهری حاصل از برهم‌کنش و همبستگی شاخص‌های فرم شهری قابل سنجش در سطح محلات، به شناسایی تمامی شاخص‌های فرم شهری قابل دسترس در سطح 368 محله کلان‌شهر تهران پرداخته است. سپس با استفاده از اطلاعات ثانویه، شاخص‌های فرم محلات و کیفیت‌های آنها را با استفاده از تحلیل عاملی اکتشافی به دست آورده است. لذا این تحقیق با روش اکتشافی تجربی و مبتنی بر روش‌های کمّی، پس از تبیین کیفیت‌های فرم شهری، محلات کلان‌شهر تهران را خوشه‌بندی کرده است. این مطالعه منجر به شناسایی شاخص‌های نشانگر کیفیت‌های فرم شهری در سطح محلات شده است. به عبارت دیگر، کیفیت‌های فرم شهری در سطح محلات، با شناسایی شاخص‌های آن و درک همبستگی‌های میان آنها به‌دست آمده است. لذا 22 شاخص و شش مولفه متراکم بودن، دسترسی به فضاهای باز و سبز، نفوذناپذیری، تنوع فعالیتی، دسترسی به قطعات و دسترسی به حمل‌ونقل همگانی به‌عنوان کیفیت‌های فرم شهری در سطح محلات کلان‌شهر تهران معرفی شده‌اند.

Exploring Indicators and Qualities of Urban Forms and Their Spatial Distribution at Neighborhood Level of Tehran Metropolis

Urban form studies have been designed to understand the dynamics and complexity of the urban structure. Urban form has been assessed based on many objectives, approaches, and related indicators. Meanwhile, the explanation of neighborhood forms and the provision of benchmarking indicators has attracted many researchers’ attention. However, in these studies urban form has been analyzed using either limited indicators compared separately, or indicators opted based on the goals or measured qualities (like sprawling, compactness, vitality, etc.) from the beginning. In each case, all the indicators and components do not cover a sufficient range of urban form indicators. Therefore, there is an inquiry to set indicators that illustrate urban form at the level of neighborhoods in order to interpret and explore the qualities from viewpoint of correlation of these definitive and clear characteristics. By providing a set of urban indicators at the neighborhood level, in addition to determining their quality, it is possible to compare the neighborhoods urban form and employ it in various studies related to urban form. To achieve this purpose, in this research, after identifying all the urban variables at the neighborhood level from different approaches and using secondary information in 368 neighborhoods of Tehran, the indicators of neighborhood forms and their quality are derived by explorative factor analysis. After determining the form variables and their quality resulting from the correlation between them, the neighborhoods of Tehran are clustered based on these qualities. The results show that 22 indicators and six denseness, access to open/green space, permeability, and diversity of activities, access to plots and access to public transportation components respectively indicate indicators and qualities of urban form at Tehran neighborhoods. Determining these quantitative and main urban form indicators at the neighborhood level can be the basis for all research related to the neighborhood form in Tehran. Moreover, the clustering of Tehran metropolitan neighborhoods based on urban form qualities shows that in areas with high denseness (central and eastern neighborhoods), access to open/green space is less and vice versa. The city center of Tehran is among the most diverse districts. On the other hand, in the central neighborhoods, the level of permeability is extremely low. In general, there is a huge discrepancy between the central neighborhoods and other neighborhoods in terms of denseness, access to open/green space, permeability and diversity. In sum, this research by identifying the urban form indicators at a specific scale (neighborhood) explores the determining and dominant urban form variables and their qualities at that very scale. Therefore, it can be said that among the approaches or goals of measurement, the scale has a significant impact on opting urban form indicators as well as the qualities of urban form. So, regarding the fact that urban form can trigger different qualities in each scale it is suggested that this concept should be assessed using the method and framework of this research in other scales to explain the qualities it can provoke in each scale.