Analysis of urban green space and the optimal location using raster calculator (Case Study: 3rd Mashhad Municipality Zone)

City parks are one of the most important urban land use and states of their distribution in city has high important in city. Zone 3 of municipal Mashhad in terms of city green space has no appropriate status so that green space per capita is 1.7 that it is away from united nation standardsand also this district in comparison to Mashhad (with 9.8 per capita) shows low proportion while the district under study in terms of population is one of the most density of Mashhad districts cityparks in order to reduction and diminish shortage and deficiencies in this district. For achieve this aim the lands of district must be valued based on criterions such as gray land, distance from educational and cultural institution, population density. Access to city infrastructure and city arteries and distance from parks and green space, than by using raster calculator model at Arc Gis. the required layers have provide and than have allocated a appropriate Weight to every layer upon their in locating green space. the 3rd zone Green space per capita is 1.7 meters, That demonstrate 774,347 square meters lack comparing with standard percapita. Considering high population density of this area, new green spaces are needed. and Base on results of combing the information layer land of district for choosing the best place for making green space, have prioritized. finally, the prioritized land compared with land use map that had consistent with present land use.