Şehir planlama süreçlerinin kentsel mekan ve arazi dinamiklerine etkileri: İstanbul örneği
Effects of urban planning processes on urban space and land dynamics: A case in Istanbul
Yazar: İLKER GÖLBAŞI
Danışman: PROF. DR. FULİN BÖLEN
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Şehir ve Bölge Planlama Ana Bilim Dalı
Derece: Doktora, 2015
Konu: Şehircilik ve Bölge Planlama = Urban and Regional Planning

Özet:
Çalışmada irdelenen temel problem şehir planlama kararlarının, stratejik kararların alındığı, belirli bir vizyon temelli üst ölçek plan kararlarından bağımsız olarak oluşturulduğu durumlarda; yörenin bütününü kapsamayan, noktasal değer artışlarının  oluşmasıdır. Bu çerçevede çalışmada farklı özellikleri olan bölgelerdeki şehir planlama kararlarının ve bu kararların verildiği plan oluşum süreçlerinin kentsel mekanda arazi değer artışları üzerindeki etkilerinin gösterilmesi amaçlanmış olup İstanbul ilinden iki bölge örnek alan olarak belirlenmiştir.  Tez kapsamında öncelikle dünya genelinde büyükkentlerin üst ölçek planlarının oluşum süreçleri incelenmiş ve plan değerlendirme kriterleri çerçevesinde İstanbul İli Çevre Düzeni Planı ile karşılaştırmalı analizi yapılarak İstanbul İli içinden çalışma konusu için uygunluk gösteren alanlar belirlenmiştir.  Çalışma alanlarının belirlenmesinde esas alınan plan değerlendirme kriterleri; planın dışsal tutarlılığı ve planın etkileme derecesi olarak belirlenmiştir. Yapılan değerlendirme neticesinde çalışmada irdelenen problemin test edileceği örnek alanlar olarak nazım plan kararları etkisinde gelişen Beyoğlu İlçesi ile parsel bazında plan kararları etkisinde gelişen Şişli ilçeleri içinden altbölgeler seçilerek plan kararlarının arazi değer artışları üzerindeki etkileri incelenmiştir. 
Çalışmada uygulama görmüş olan plan kararlarını kapsayan dönem olan 2006-2010 yılları esas alınmış olup örnek alanlarda bu dönemdeki planlama süreçleri içerisindeki plan kararları, nitelikleri ve oluşum süreçleri bakımından sınıflanmış ve bu plan kararlarının mekansal dağılımları ortaya konmuştur. Ardından 2006 ve 2010 yılları için, çalışma alanı dahilinde, ele alınan planlama kararlarının verildiği alanlara bitişik parsellere cepheli sokak ve caddelere ilişkin birim m² arazi değerleri saptanmış ve bu değerlerin yine 2006 ve 2010 yılları için plan kararlarıyla karşılaştırmalı analizi yapılmıştır. Son olarak da her bir analiz alanının hem kendi içinde hem de birbirleriyle gruplandırma, korelasyon ve regresyon yöntemleri ile kıyaslanarak benzerlik ve farklılık gösteren özellikleri saptanmıştır. 
Elde edilen sonuçlar göstermektedir  ki stratejik kararların alındığı, belirli bir vizyon temelli üst ölçek plan kararlarından bağımsız olarak verilmiş olan parsel bazında plan kararlarından içinde ticaret alanı olan ve emsal artışı öneren plan kararları, nazım plan kararlarından farklı olarak yüksek düzeyde ve noktasal arazi değer artışları oluşturmaktadır. Çalışmada plan kararlarının arazi değer artışları üzerindeki etkileri incelenirken 2006-2010 yılları arasındaki değişimler ve plan kararları dikkate alınmış olup çalışmanın yapıldığı örnek alanlarda 2010 yılı sonrasında da parsel bazında plan kararlarıyla kentsel mekanda uygulamalar devam etmektedir. Bu çalışmada elde edilen bulgular bundan sonra bu konuda yapılacak çalışmalara yön vermesi bakımından önem arz etmektedir.

Abstract:
The main problem addressed in this study is that in such cases where urban planning decisions are constituted independently from the strategic upper-scale plan decisions which are based upon a specific vision, there take place local value increases which do not cover the whole area. Within this framework, it is aimed to put forth the effects of urban planning decisions in regions with different characteristics and the relevant planning processes where these decisions are taken on the land value increases in the urban space. To this aim, different methods were used so as to test the problem examined herein in line with the various assumptions and literature review was conducted for the theoretical framework.  
Establishment of the theoretical framework covers a general literature research for the already developed theories in this field and the previously conducted studies. Accordingly, the subjects designated as the main areas of interest of this study are as follows: rent-value concept, urban ground rent, land values, urban planning processes and economic value relations of the urban planning processes. 
Urban planning decisions, based on their nature, cause different effects on the land values and when functions change with zoning decisions, effects on the land values differentiate as well. In line with this assumption, land value increases which are connected with the urban planning decisions for different regions and with different functions were analyzed. Furthermore, lands which are located around the plan decisions proposing commercial activities bring about value increases. This finding is important to lay down the relation between the plan decisions suggesting commercial activities and the land values in the examined regions of the study. Among the social reinforcement areas, urban green space plan decisions create value increases for the surrounding lands and houses. Therefore, effects of the urban green spaces, which are proposed under the different plan formation processes, on the land value increases were analyzed and which characteristics of the green spaces are effective on the land values were determined.    
After the theoretical framework regarding economic value relation of the urban planning processes was specified; London, New York, Paris, Montreal and Lisbon were chosen among the large cities worldwide, their upper-scale formation processes were examined, plan success assessment was performed on the basis of certain assessment criteria and the elements which are pertaining to economic effects of the planning decisions on the urban space were designated. Plan assessment criteria were specified as internal coherence, external coherence,  plan relevance to the city needs and ambitions, public participation, commitment of human and financial resources and plan effectiveness.
Subsequently, plan success assessment of Istanbul Environmental Plan was performed based on the assessment criteria above and it was analyzed comparatively with upper-scale plans of the large cities worldwide. Plan assessment criteria which are important for the the case study are external coherence and plan effectiveness. As a result of the analysis, it is found that sub-scale planning and application activities which are generally conforming to the plan decisions were conducted for New York, London, Montreal and Paris plans whereas sub-scale planning and application activities which are partially conforming to the plan decisions were conducted for Lisbon plan. When Istanbul Environmental Plan was compared with the sub-scale planning decisions and applications, many applications were found out to be independent from the strategic objectives, policies and planning decisions of the upper-scale. 
The fact that Istanbul Environmental Plan includes strategic objectives and planning decisions which do not match up with the sub-scale planning decisions and applications especially in the central business district and in the north of the conventional central business district and that there are plans and applications independent from upper-scale plans due to plot-based plan decisions such as local zoning plans and plan amendments, etc. in these areas are among the issues that come forward regarding the problem addressed in this study. Within this framework, the areas which are suitable for this study were designated in Istanbul. Pursuant to the assessments, sub-regions were selected - as the sample areas where the problem herein will be tested - from Beyoglu district which has developed under the influence of master plan decisions and Sisli district which has developed under the influence of plot-based plan decisions and effects of the plan decisions on land value increases were examined.      
Years 2006-2010 which cover the applied plan decisions have been taken as basis in the study; plan decisions within the planning processes of the sample areas were classified in terms of their qualities and constitution processes and spatial distribution of these plan decisions were put forth. Subsequently, land values per square meter were established for the streets and avenues which face the plots adjoining to the areas for which the adressed planning decisions were taken between 2006 and 2010, and these values were analyzed again comparatively with the plan decisions of 2006-2010. Finally, each survey area was compared in itself and with one another through grouping, correlation and regression methods and similarities and differences were specified. 
Following the analysis results of street and avenue groups and according to the field visits in the sub-regions of Beyoglu district and the interviews held with real estate agents, there were determined different characteristics and applications effective on the land value increases, apart from the master plan decisions. Different characteristics of the area are that buildings which face the streets and avenues are new and well-kept; there are no worn-out and unused buildings; streets and avenues are more favorable in terms of topography and slope and the region is preferable due to social environment and security issues. Morever, some applications carried out by the local municipality in the region are the efective factors apart from the plan decisions. These applications of the local municipality include the street landscaping and facade arrangements as well as the works performed at the entrances/exits of the subways for transportation. Besides, pursuant to the analysis, it is understood that land value increase rates of the streets and avenues which are located in the sub-regions of Beyoglu district and remain under the influence of master plan decisions are close to the general average and exhibit a homogenous distribution while land value increase rates of the streets and avenues which are located in the sub-regions of Sisli district and remain under the influence of plot-based plan decisions have great differences. Therefore, the two sub-regions are observed to have distinct characteristics.         
According to the correlation analysis which aim to designate the relation of the land value increase rates with the master plan and plot-based plan decisions, it is seen that effectiveness of the plot-based plan decisions, which are taken in the sub-region of Sisli district, on the land value increase rates is different from the master plan decisions, in the sub-region of Beyoglu district and it causes a positive effect of higher degree. 
Correlation analysis results show that in order to specify the effects of function types on the land values, it would be more convenient to separate the plot-based plan decisions and master plan decisions and to find out their respective level of effectiveness. 
As a result of the multiple regression analysis which were conducted to find out the relation between land value increase rates and master plan decisions, it is implied that health facility (hospital) area and park-square area plan decisions which are proposed in all master plan decisions of the sub-region of Beyoglu district cause low-level increases on the surrounding land values. Land value increases which are caused by the health facility (hospital) area plan decision are higher than the increases triggered by the park and square plan decision in all master plan decisions taken in the sub-region of Beyoglu district. Planning the health facility (hospital) areas based on the regional needs and in a manner to serve the region increases its availability and significance and correspondingly creates positive effect on the land values. Considering the master plan decisions in the sub-region of Beyoglu district, aerial size of the park and square plan decisions changes the effect of the concerned plan decisions on the land values. It is possible to see the aerial size of the park and square plan decisions as a factor which is effective on land values. In the park and square plannings, aerial sizes and design principles may increase usability of these areas and render more functional uses. Therefore, availability, functionality and design quality of the parks and squares may create increases on the surrounding land values. 
As a result of the multiple regression analysis which were conducted to find out the relation between land value increase rates and plot-based plan decisions; it is seen that plot-based plan decisions in the sub-region of Sisli district cause high-level of effects on the surrounding land value increase rates, in contrast to the master plan decisions in the sub-region of Beyoglu district. It is possible to explain this situation with the fact that the plot-based plan decisions are not a part of the plan decisions which cover the whole region, they are not developed in line with the urban demands and needs of the whole region and they lead to value increases in their immediate environment. Among the plot-based plan decisions applied in the sub-region of Sisli district, even if the aerial size of the trade-tourism area, trade-service-house (mixed use) area and transfer center area plan decisions differentiate, they create centers of attraction by providing commercial activities, economic activities and dynamism in the surroundings. Therefore, they result in high level of land value increases in the immediate vicinity. In addition to the differences of functional types, taking the equivelant increase suggestions into evalution is important to explain the effects of plot-based plan decisions on the land value increases more accurately and healthily. When effects of the plot-based plan decisions on the land value increases are assessed, together with the equivalent increase suggestions, in the sub-region of Sisli district, they are observed to cause high-level of land value increases in the immediate vicinity in parallel with the aerial assessment and the analysis performed only with the function types. Plan decisions which affect the land value increases both according to aerial values and also independently from them are, at the same time, the plan decisions which propose equivalent increase. It is seen that equivalent increase suggestions of the plan decisions are an important factor which has an effective role in land value variances.                   
The obtained results show that among the plot-based plan decisions which are taken independently from the strategic upper-scale plan decisions which are based upon a specific vision, those which include commercial areas and suggest floor area ratio increase constitute high level and local land value increases, contrary to master plan decisions. While effects of the plan decisions on the land value increases were examined in the study, changes and plan decisions between 2006-2010 were taken into account and in the sample areas of the study, urban applications still continue in post-2010 period as well through plot-based plan decisions. Findings to be obtained in this study are important in that they would guide the following studies in this field.