Developing the model of research method in urban landscape studies emphasizing the Saunders’ research onion

The urban landscape is part of the understandable objectivity of the reality of the existing space around people in the city. As a phenomenon, urban landscape cannot be assumed to have only subjective or objective dimensions. The connection between different methodological components in different fields of landscape research is always necessary. The research aims to strengthen the necessary foundations of research in urban landscape with a holistic, comprehensive viewpoint by examining the components and layers that the onion model of urban landscape research includes. Therefore, a systematic review was applied of the articles conducted in the field of urban landscape. The identification and analysis of the cases used in the majority of the research onions presented by Saunders et al. led to the urban landscape research onion through changes applied to this model. Researchers can choose their lines of research more accurately and faster using the research onion.

Theoretical Framework:

Specifically in the field of research methodology, a book entitled Research in Landscape Architecture: Methods and Methodology was published in 2017 by Routledge Publications. This book deals with the conflict between objectivists and subjectivists. It states that pragmatism is the only solution to this duality (Hashemizadegan, 2019: 55). In addition, many studies have been conducted with an emphasis on urban landscape and its relationship with other urban concepts. However, there has not been a comprehensive viewpoint on their methods and processes. The research onion (moving from the outer layers to the core) was developed by Saunders, Lewis, and Thornhill (2016) for business studies. It is widely used in social sciences to construct a theoretical framework for research. In various studies, the layers proposed in the research onion model have been modified and changed according to the field of study. The research onion consists of six main layers: research philosophy, approach to theory development, methodological choice, strategy, time horizons, and techniques and procedures including data collection and analysis (Melnikovas, 2018: 33; Sahay, 2016: 1).

After a search of article titles and keywords for the concept of urban landscape, more than 110 with more citations were selected. After a study of the article abstracts and other preliminary studies, 71 articles were selected, analyzed, and categorized using the qualitative method and content analysis. Finally, the research onion for each of the areas (the concept of urban landscape, visual evaluation of landscape, and visual management of landscape) was drawn and explained. Then Comprehensive research onion could use in landscape study and research compiled.

The research conducted in Iran in the field of visual management of landscape has generally been carried out at the macro scale (city), medium scale (watercourses and parks), and micro scale (streets). The survey research method and the descriptive-analytical approach have been adopted to investigate and analyze the current situation with the questionnaire tool. Many articles in the field of visual management have evaluated the visual aspects of landscape. Visual evaluation of the landscape is proposed as an independent concept in the field of landscape. In the field of evaluation, it is possible to become closer to people’s experience; therefore, quantitative methods, an experimental approach, a variety of techniques and analytical tools, such as visual protection levels, and Philip Thiel’s technique were used.
The concept of urban landscape was addressed further with a view of the landscape as a whole. Aesthetic, critical, and semiotic theories were proposed as the theoretical support for the studies. The research process pursued in most of them is qualitative and analytical, and comparative, inductive, interpretive, and descriptive methods have been used therein. After choosing the desired method, the authors have used the Delphi technique, aerial photos, cluster analysis, systematic review, in-depth interview, review of narratives, photography, and collaborative mapping as data mining and data analysis tools. The model presented in this article involves an extra layer with respect to Saunders’s research onion model. The outer layer, which includes the ontology of the research, corresponds to the stage that specifies the researcher’s beliefs in the research process. The researcher must select their position from among the three categories of objectivist, structuralist, and subjectivist, as considered by Deming and Sowfield.
A) The descriptive approach is added to the analogical inductive one proposed in Saunders’ research onion.
B) In the strategy layer, experimental simulation and descriptive, correlational, hermeneutic, and analogical-adaptive analysis are added.
C) In terms of time horizon, all studies are placed in one of the two categories of longitudinal and transverse research, and most of them are conducted with a longitudinal time horizon.
D) Techniques and procedures are proposed in the central core of the urban landscape research onion. Research techniques are divided into two general categories with an emphasis on the opinions provided by experts: direct (by asking people) and indirect (through specialist analysis) (Karimi Moshaver, 2013; Tveit et al., 2006; Briggs & France, 1980).

The urban landscape research onion model is composed of seven layers. It can be of different types according to the research problem, questions and objectives, choice of ontology, methodology, approach, strategy, and appropriate tool for analysis of the collected data. Given that most of the conducted studies applied various techniques, it is necessary to consider other layers of the research onion. This model attempted to provide a comprehensive overview of urban landscape research and introduce an integrated framework of the diverse, scattered types thereof. The model can help determine the paths of the research and avoid confusion and incorrect choices of analytical tools. The onion of urban landscape research can open the doors to researchers in the field. In future research, emphasis can be made on the specific concepts of landscape such as cultural landscape and vernacular landscape. On the other hand, similar research onion models in the field of urban landscape can be investigated with an emphasis on landscape scale (micro, medium, or macro).

This article is extracted from the first author's PhD thesis in titled "Explaining a semantic model of the urban landscape; a case study of the urban landscape of Shiraz". It is in progress at the Art University of Isfahan under the guidance of Dr. Mahmoud Ghalehnoee (the first guide) and Dr. Armin Behramian (The second guide).