Introduction 
Urban development plans create added value through urban planning and investment in infrastructure. Many urban planners, considering the changes in the value of real estate and land in urban development plans, have tried to regulate and implement methods that benefit the beneficiaries of urban development in the process of developing cities. require to pay at least a part of this added value to the city administration. In this regard, paying attention to the components of spatial justice to reduce inequalities is emphasized by urban planners. In this research, different approaches for obtaining added value resulting from the implementation of urban development plans and compensating owners from the point of view of spatial justice and methods of redistributing private benefits resulting from guiding the development of cities have been investigated. To achieve correct planning in urban development plans, one must have sufficient knowledge of the dimensions and number of factors affecting the added value resulting from the implementation of development plans. The analysis of the added value of urban lands indicates the multiplicity and complexity of factors affecting the value of real estate and city lands, such as macro-financial and monetary policies, urban management policies, inflationary trends, and the amount of supply and inventory of housing and urban services. In this research, the factors affecting the value of land and urban properties have been divided into internal and external variables. The internal variables of the added value of real estate and urban land include issues like the size of the plots, the location of the land, the condition of the property, and the owner’s investment. The added value is caused by public measures including various urban development projects, and the creation of urban infrastructure. It is only possible to study the effect of urban development plans on the value of urban land and real estate if the effect of other factors on the value of urban land is removed. So, in this research, the land price situation of the studied city (Golpayegan city in Isfahan province), in the year of preparation of the city development plan, was weighted and assigned a number between zero and one. In this method, land prices compared to other parts of the city were determined relatively. The same operation took place after the implementation of the development and urban planning of the city and in the year of preparation of the detailed plan. According to the standardized maps, at this stage, it was possible to analyze the changes in the value of urban land through GIS software.
Materials and Methods
This article is descriptive-analytical in terms of nature and content. On the other hand, this research is practical in terms of its purpose, because it can be applied to solve practical and real problems and has a practical application. In terms of time, it is also cross-sectional. In this research, the increase in the value of land and real estate due to urban development and development plans and different approaches to obtaining the added value of land in development plans have been investigated. Also, the changes in the value of urban land in Golpayegan city over 10 years (in 1390 during the preparation of the development and urban plan of the city and in 1400 after the implementation of the plan and the preparation of the detailed plan of the city) were investigated. Also, the amount of changes made in different uses and their distribution in the city was determined from the perspective of spatial justice. First, spatial justice criteria were identified in comprehensive plans and these criteria were evaluated from the point of view of urban planning experts and the urban planning experts who were involved in the preparation of urban comprehensive plans. Furthermore, 100 sample questionnaires were completed. The components of spatial justice were selected by evaluating more than 100 scientific sources that were most suitable for the topic. Finally, using the coding technique and semantic units, categories were compiled in the form of principles and criteria of social and spatial justice. According to the criteria of spatial justice, a questionnaire was completed in the form of 20 items corresponding to the criteria and metrics of spatial justice. The adequacy of the sample size according to the number of variables and using KMO data tests for factor analysis is equal to 0.773 which is an acceptable number. The analysis of the findings was done using the exploratory factor analysis technique. Spatial justice criteria have been examined using secondary analysis in the components of spatial diversity and equality and non-discrimination, attention to the needs of citizens and differences in favor of the deprived, participation and observance of citizenship rights, and transparency and agreement.
Findings
After the implementation of the Golpayegan development plan, many things have influenced the changes in the added value of urban properties, including the determination of urban land use, the determination of the city limits and the creation of a road network, construction rules, and regulations and the zoning of the use of different uses. In the studied sample, determining and changing the use of urban land for profit and non-profit has directly affected the added value of urban land. In the parts of Golpayegan city where the density of commercial uses has been suggested, the changes in land value are positive and more than in other parts. From the comparison of the relative changes in the value of land compared to commercial uses, it seems that after the implementation of the plan, the increase in the price of land and real estate in the main axes of the city has grown more than in other parts. Of course, due to wear and tear and lack of attention to renovation, we see a decrease in added value compared to other sectors in the old commercial axes. Urban development plans within the framework of comprehensive and detailed plans, through the application of construction rules, determining the minimum or maximum area of land plots, and determining the ratio of the building to the land area, ground floor coverage, and density can help to achieve spatial justice. 
Conclusion
The results of the plan review and analysis show that the criteria of spatial justice in urban development plans are at a low level, and to understand the results of the increase in land value, it is necessary to analyze the relationship between planning approaches and spatial justice criteria.