کاربریهای عمومی در بسیاری از شهرها به دلایلی چون عدم توجه به معیارهای مکان گزینی و شعاع دسترسی و آستانه های جمعیتی، قادر به ارائه خدمات مطلوب به شهروندان نمی باشند. این موضوع در شهرهای بزرگ و بویژه برای کاربریهایی نظیر فضای سبز از نمود بیشتری برخوردار است. در خدمات رسانی شهری تنها افزایش تعداد مراکز خدماتی، دلیل بر خدمات رسانی مناسب نبوده، بلکه آنچه حائز اهمیت است، توزیع بهینه این مراکز می باشد نوع تحقیق کاربردی است. روش حاکم بر این پژوهش " توصیفی ـ تحلیلی" است. جامعه آماری، منطقه 4 شهر شیراز می باشد. در این تحقیق با استفاده از مدل های برنامه ریزی به نتایج زیر رسیدیم. کاربری فضای سبز با توجه به جمعیت و مساحت هر یک از مناطق نه گانه شهر شیراز بررسی شد و بیانگر این نتایج بود، که بالاترین سرانه فضای سبز شهری در منطقه 3 و کمترین حد سرانه مربوط به مناطق4، 7، 8 و 9 می باشد. همبستگی اسپیرمن رنک بین جمعیت و مساحت فضای سبز مناطق، معادل 78/0 می باشد. و توزیع پارامترهای مساحت فضای سبز و جمعیت در سطح مناطق شهری شیراز با توجه به میزان ضریب جینی معادل 16/0 می باشد. که این دو شاخص نشان دهنده توزیع نسبتاً متعادل فضای سبز و جمعیت مناطق شهری می باشند. اما این نشان دهنده مکان بهینه و دسترسی مطلوب تمام شهروندان به پارک های شهری نمی باشد. گسترش فیزیکی شهر بیشتر در مناطق 4 و 9 می باشد که با توجه به افزایش جمعیت در این مناطق، نیاز به ایجاد فضای سبز در الگوی پارک های محله ای و ناحیه ای می باشد. بر این اساس مطالعه موردی منطقه 4 با تراکم جمعیتی بالا، انتخاب شد و با تلفیق لایه های مختلف با وزن های مشخص در محیط GIS، پارک های ناحیه ای در نواحی شهری 5، 6 و 9 منطقه 4 مکانیابی شدند.
عنوان مقاله [English]
An Analysis of Urban Green Space Landuse Using the Techniques of Urban Planning (Model Spearman Rank, Gin Index, FAHP, Overlap model) in GIS (Case Study: Shiraz District 4)
Quantitative changes of green space in cluding loss of green space are the result of changes of landuse and fragmentation of its surfaces, and changes in species composition and green space density and degree ofconnection of green spots may indicate the qualitative change. The diverse functions ofurbangreen space play aprominent role in improving quality of life of citizens and hence constitute the key factor in shaping a sustainable city. Increasing evidences indicate that the presence of green areas in city increase the quality of life in many ways. In addition, many of the environmental services of urban green space provide psychological benefits to human communities, source of positive feelings, achieving non-financial services and consumer benefits and enrichment of human life. One important feature of GIS is modeling. Modeling and its use are considered as important principles in geographic researches by researchers. Location models are set of principles by help of which optimization of service activities is explained.
The purpose of applied research is development and improvement of methods and structures. This research is apart of applied research. Its approach is "descriptive - analytical". The statistical community includes districts of municipality of Shiraz. First, field, spatial and needed feature data were collected through maps of present situation of comprehensive plan of Shiraz, detailed plan review of District 4, statistical year book of the city of Shiraz in 1387 and sites associated with there search council of Shiraz. With data (population, area of districts, area green space and per capita of green space, etc.) added to GISâs spatial data, a database was built. Using the spearman rank correlation indicator and gini coefficient, we analyzed the distribution of landuse of green space districts and optimally located regional parks with overlapping layers by weighting method FAHP. To analyze statistical data and spatial data and mapping Excel and Arc Map (GIS) are used respectively.
By urban green spacesâ per capita it is meant useful per capita of spaces that have functions of move, leisure and social for people, not biological per capita which includes all surfaces of green spaces. Considering the population and area of all the 9 Shiraz districts, the per capita of green spaces is about 12.13 square meters in 1387. Accordingly the per capita of green space of Shiraz is appropriate to standards of the Ministry of Housing and Urbanization, but it is less than international urban green space which is about 20 to 25 square meters per person. The District 3 has the highest level of per capita green space. Because of low population density and small size of district to area of green space, we observe the standard level of per capita green space in the Districts 1 and 6 less than that of 2, 4, 7 and 8. District4, which will be checked, has most of its green spaces composed of neighborhood parks and a regional park, and population density is high therein.
Assessment of implementation of green space landuse District 4 with detailed and comprehensive plan proposals of green spaces of Shiraz
Evaluating the rate of changes with the recommendations of detailed plan indicate that the most changes are related to green space and 39/5 % of the landuse is changed into other types of landuse. However, only 2.2% of the proposed residential landuse has been converted into other sorts of landuse. Comprehensive plan of green space of Shiraz is prepared by consulting engineers from Pouyesh Jonoub with aim of creating a green city. The mentioned plan has dealt with estimating the required parks in detailed plans of 9 districts (year 2021) regarding locating urban parks in the detailed plan districts and according to model of central place. Evaluating the location of regional and neighborhood parks of detailed plan of green space and their consistency with present District 4 of municipality indicate that two regional and six neighborhood proposed parks of this plan is located in District 4. As with the proposals of plan about the District 4 considering proposed criteria of the plan including legal, socio-economic and ecological locating, ownership and ease of ownership of land by them unicipality (locating legal) are accounted for. Thus the proposed location is consistent with the detailed plan. And now none of the neighborhood parks in the area has begaun to be constructed.
Much of physical expansion of the city is occurred in Districts 4 and 9 which due to increasing population in them it is required to create green space in the pattern of neighborhood and regional parks. Accordingly, the high population density of District 4 is chosen as a case study. To locate parks the model of overlapping of layers in GIS is used. 4 layers including 1: Population density layer, 2: Access network layer, 3: Landuse of industries layer(consistency and inconsistency), 4: Landuse of waste land bayer, are prepared from map of district and the weight of each layer is determined by weighting method in FAHP.
Optimized locating to construct parks by the system provides more possibility of decisions for planners. Thus, using fuzzy logic and overlapping layers identified sites of neighborhood parks, which could be suitable and desirable locations for regional parks, considering future expansion of the city.
Landuse of green space considering population and area of each district of Shiraz is evaluated indicating highest per capita urban green space is in District 3 and the lowest per capita is for Districts 4, 7, 8 and 9. Spearman Rank correlation between population and land area of green space is equivalent to 0/78. Distribution of the area parameters of green spaces and population in the urban districts of Shiraz according to gini coefficient are 0/16, both of which indicate a relatively balanced distribution of green space and population of the districts. But this does not mean the optimum location and good access of all citizens to urban parks. Results of optimal locating neighborhood parks with overlapping of various layers with a specific weights in GIS, urban neighborhoods of 5, 6 and 9 were located in District 4.