کاربرد مدل معادلات ساختاری در تبیین نقش عوامل مؤثر بر تحقق پذیری طرح های توسعه شهری (مطالعه موردی: شهر شیراز)
محورهای موضوعی : فصلنامه علمی و پژوهشی پژوهش و برنامه ریزی شهری
ناصر رضایی
1
(دانشجوی دکتری، گروه شهرسازی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران)
حمید ماجدی
2
(استاد، گروه شهرسازی، دانشگاه دانشگاه آزاد اسلامی، واحد علوم و تحقیقات، تهران، ایران)
زهرا سادات سعیده زرآبادی
3
(دانشیار، گروه شهرسازی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران)
حسین ذبیحی
4
(دانشیار، گروه شهرسازی، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران)
کلید واژه: تغییر کاربری, شیراز, کاربری زمین, طرحهای توسعه شهری, معادلات ساختاری (SEM),
چکیده مقاله :
طرحهای توسعه شهری در ادامه سیر تکاملی خود با هدف خدمت به بشر و با الگو پذیری از مؤلفه های توسعه پایدار به سمت هر چه کاراتر شدن پیش میرود. در این بین یکی از اهداف مهم این طرحها تأمین خدمات اساسی و زیرساختها برای توسعه همه جانبه سکونتگاههای انسانی است. در این راستا هدف اصلی این پژوهش تبیین عوامل مؤثر بر تغییر کاربری‌های خدماتی در شهر شیراز و شناسایی دلایل آن می‌باشد. پژوهش حاضر نوعی تحقیق تحلیلی است که ابتدا با بهره‌گیری از منابع اسنادی- کتابخانه‌ای، مفاهیم مرتبط با تغییر کاربری اراضی مورد بررسی قرار داده و سپس میزان شدت نحوه اثرگذاری عوامل چهارگانه (کالبدی، فعالیتی، اقتصادی، دسترسی) بر تغییر کاربری زمین و سپس میزان مطلوبیت این اثرگذاری مورد بررسی قرار می گیرد. برای این منظور ابتدا برای تعیین شدت اثرگذاری عوامل چهارگانه بر تغییر کاربری زمین از فن تحلیل عاملی تأییدی مرتبه دوم استفاده گردیده است، تا بدین طریق چارچوبی تبیینگر برای اثرات نحوه اثرگذاری عوامل چهارگانه بر تغییر کاربری زمین حاصل آید و در نهایت با استفاده از مدل معادلات ساختاری (SEM) ، میزان و جهت عوامل مؤثر بر تحقق‌پذیری کاربری‌های خدماتی را در شهر شیراز تبیین گردیده است. در مجموع برای نیل به این اهداف ابتدا 50 متغیر تأثیر گذار بر روی 600 قطعه در شهر شیراز به صورت میدانی برداشت و با استفاده از نقشه‌های GIS و نرم افزارهای Amos و SPSS مورد تحلیل قرار می گیرد. نتایج تحقیق نشان میدهد که در مجموع عوامل چهارگانه منتخب تأثیر بسزایی بر میزان تغییرکاربری دارند (با توجه به اینکه وزن استاندارد شده رگرسیونی برای «میزان تأثیر عامل دسترسی بر تغییر کاربری زمین»، «میزان تأثیر عامل اقتصادی در تغییر کاربری زمین»، «میزان تاثیر عامل فعالیتی در تغییر کاربری زمین» و «میزان تأثیر عامل کالبدی در تغییر کاربری زمین» به ترتیب برابر با 0.91، 0.78 ، 0.65 و 0.56 می باشد).
Urban development plans are progressing towards becoming more effective in their evolutionary process, with the goal of serving human beings with a modeling of sustainable development components. One of the major goals of urban development plans is the provision of basic services and infrastructures for the full development of human settlements. In this regard, the main purpose of this paper is to explain the factors affecting the change of service landuses in the city of Shiraz and identify its reasons. This research is an exploratory research, which first studies the concepts related to land use change using document-library sources and then investigates the severity of the effect of the four factors (physical, activity, economic, accessibility) on land use change and their desirability. For this purpose, the second-order confirmatory factor analysis technique has been used to determine the severity of the effect of the four factors on land use change, through which a contributing framework for the effects of the four factors on land use change is obtained. Finally, the extent and direction of the factors affecting the realization of service land uses in the city of Shiraz are explained using the structural equation model (SEM). In order to achieve these goals, 50 variables affecting 600 plots in Shiraz city are extracted through field method. The variables are investigated and analyzed using GIS maps, Amos and SPSS software. The results of the research show that, in total, the selected four factors have a significant effect on the land use change. It is such that the standardized weights of regression for "the effect of the access factor on land use change", "the effect of the economic factor on land use change", "the effect of the activity factor on land use change", and "the effect of the physical factor on land use change" are 0.91, 0.78, 0.65, and 0.56, respectively. Extended Abstract Introduction: As the rapid growth of population and the development of cities, especially metropolises have led to rapid changes in the land use patterns in and around cities, the majority of urban planners have emphasized the need to rethink the urban development plans, with particular emphasis on their feasibility, especially in land use, at a variety of time points. Although these urban development plans are costly and time consuming and have significant impacts on land use zoning and adherence to building regulations, they have not been feasible for some reason. One of the major goals of urban development projects in cities such as Shiraz metropolis is to provide essential services and human and urban infrastructure for the comprehensive development of human settlements. However, like many other big cities, Shiraz, which has been experiencing high population growth and poor physical development, has faced numerous challenges in realizing its urban development plans and goals, including the anticipated land uses and essential services and infrastructure. Since several factors influence the feasibility of urban development plans, the main question of this paper is to determine what factors and to what extent have influenced land use change in Shiraz for the past 20 years. The main purpose of this paper is to determine the factors that affect the implementation of urban development plans and land use changes in Shiraz and specify the complex relationships between these factors using structural equation modeling (SEM). Methodology: In order to achieve the abovementioned goal, applying SEM structural equation modeling in analyzing the relationships of variables and achieving the optimal land planning model, the causal relationship as well as the hidden and explicit variables have been found at the level of complex equations. In this context, used documentary-library resources, the concepts related to the land use change have been studied first. Then, the impact of the quadripartite factors (physical, activity, economic, accessibility) on the land use change and the desirability of this impact have been investigated. To this end, second-order confirmatory factor analysis technique as one of the structural equation modeling techniques has been used to determine the severity of the effect of these quadripartite factors on the land use change, achieve an explanatory framework to specify this effect and finally, explain the extent and direction of the factors affecting the feasibility of service applications in Shiraz. In total, to achieve these goals, first, 50 variables affecting 600 sections have been field-sampled in Shiraz (their land use has been changed in Article Five Commission from 1994 to 2017) and analyzed using GIS maps as well as Amos and SPSS software to examine a set of bivariate correlations in a table called correlation matrix or covariance matrix, the most important of which are confirmatory factor analysis and structural equation modeling (SEM). RESULT AND DISCUSSION Using SEM, it was found that the selected four factors (physical, activity, economic, accessibility) have a significant effect on the land use change. It is such that the standardized weights of regression for "the effect of the access factor on land use change", "the effect of the economic factor on land use change", "the effect of the activity factor on land use change", and "the effect of the physical factor on land use change" are 0.91, 0.78, 0.65, and 0.56, respectively. Moreover using SPSS software, more than 50 parameters were analyzed in about 600 plots having land use changed during 1994-2017 and the following results were determined: Most land use changes were in districts 1, 2, 7, 5, 3, 4, 10, 9, 6, and 11. 91% of the plates that had land use change during the years 1994 to 2017 had land use change in other plates within a range of around 500 meters radius. 95% of the plates that had land use change were outside the heritage zones and 50% of the plates that had land use change from 1994 to 2017 were far from natural zones and the other half was near the natural zones. More than 88% of the plates that had land use change from 1994 to 2017 were not on the development path of the city. Approximately 50% of the plates that had land use change from 1994 to 2017 had a good, high-quality landscape. Among the plates that had land use change from 1994 to 2017, 21.3% had a garden use in the detailed plan approved in 1994, 18.2% had a residential use, 15.1% were in the urban area, 13.6% had a park and green space use, and 11.4% had an educational use. The range of price changes of lands that had land use change varied from 500 to 10 million Tomans per meter, indicating that all urban lands with different economic positions are affected. In 73% of the land use change cases, the density predicted for land in the review plan is not proportional to the land economy. 61% of plates are within the scope of effective urban projects, 36% are not within the scope of effective urban projects, and 1.4% are negatively affected by urban projects. CONCLUSION: Generally the results indicate that in an exploratory factor analysis process, the structural equation model (SEM) was used for the first time in order to clarify the relationship between criteria and indicators of the effectiveness of urban development plans. Also, the effect of new indicators was also explored in the research process which indicated that the model is a suitable tool for developing the hidden and obvious variables of the research subject as well as providing new indicators for feasibility studies in Iranian examples in international studies.
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