Evaluation of middle scale urban form in accordance with transect as a theory and approach

In different periods, urban form as substantial dimension of urban design has been core issue involving all urban designers with different approaches. The literature reviewing indicates that urban form can be treated with various approaches under positive or normative point of view. According to the issues involved in urban measurement, different point of views lead to explore three interrelated aspects of urban s tudy- the Measurement, Evaluation, and Representation of urban form. In addition there is a need to adopt a strategic approach in dealing with urban issues. Therefore, the paper considering with normative point of view put emphasis on urban form evaluation.
In recent years, mos t recent innovation of new urbanism so called “transect” has been a very common theory and approach in urban design and planning specifically in America and Europe, although it is being used in a limited way in the Middle East. The transect approach described in this paper is based on a publication known as the Lexicon, a multi-authored compendium of New Urbanis t definitions and codes. Urban design and planning seek to create an immersive environment. This type of environment can be created by specifying and arranging the elements which comprise that environment in a way that is true to locational character which seems to be intrinsic to the place. To be immersive in urban environments is identified with their level and intensity of urban character. There is no scrutiny of how urban form has been created in accordance with transect theory and transect approach is characterized while much more research has been done on transect theoretical framework. Therefore the paper presents an overview of transect as theory and approach, exploring how urban form can be evaluated in accordance with transect.
In this regard, transect indices are identified by using three-s teps research methodology that is characterized in determination of “dimensions”, “components” and “indices”. Principles of transect are categorized in “substantial” and “procedural” dimensions. This research uses “ecology” as a basic discipline for interpretation of “components”. In other words, “ecology” has been a reliable criterion to extract indices. In this regard, basic concepts of ecology conceptualizing transect are recognized—“ecosys tem”, “community”, “diversity”, “succession”, and “coevolution”. Afterwards, critical issues and concepts that have to be redefined in order to interpret of “components” and “indices” are determined by comparative comparison between transect and ecology as basic discipline. In addition, it’s done to redefine basic concepts in macro level – scale and context – in transect in according to what they are meaning in ecology. Therefore, transect indices are extracted from these basic concepts as “components”. They are as follows: “juxtaposition”, “locational sequence”, “suitability between urban elements types and urban character of environment” that has been defined by “number of types been found” and “population of elements with specific type”, “suitability between urban elements compared to each other”, “diversity of transect zone types”, “diversity of urban elements types”, “climax”, “transition”, and “coevolution of urban elements”. Eventually the paper present a framework in order to quantify these indices according to relative abundance formula.