analysis of trend of spatial development of rasht city and determining optimal directions of its development using of gis

extended abstract introduction disproportionate development of cities and extended accumulation cause the phenomenon like as informal settlements. and the results of developing the informal settlements are forming different damages of economy, society and environment. results of thisseductions are inability of city a spaces in answering to largess necessity. generally this unbalance urban growth forms in unprepared lands of city and its results are like as increasing unutilized lands, increasing open spaces, decreasing the accumulation of population separation of urban and social units: so the important issue that stays against the urban development is their future develop place. recognizing and choosing a best place to future develop of city requires observing the roots and best development of criteria orientation. in finding place we try to rest the different parameters of relationship with each other. methodology all the opinions and patterns of developing city can’t perform in a city because each of them have its own morphology, but can be useful as principal lines to know the studied pattern of developing city and in other cities. each of these opinions don’t show special facts and a city may compose of several pattern and opinion. harris and oilman the famous american geographers discussed “multi cores structure” by using of berges opinions. this opinion shows that the units of city develop in several surrounding of a separate center and each core can be a first point of city stability. among other opinions that used in relationship with developing of city space, there is the opinion if stellar shape if town, the city in a shape of star can’t prove a stable and resident town. but it is often because of development of town movable and unstable. the development of city can be practical in two ways: develop around of it or develop by using of focused operation in itself, in star shape city has a principal center that have important networks and usually, there are spaces in linear shape and distance of basic networks in an empty spaces including forming or open land and generally, the cyclic into inner and outer graders. results and discussion purpose of this paper is studding the way of frame – physical development in rasht, knowing the effective factors in areal development of town, analyzing the direction of development and patterns of physical growth in town, recognizing the abilities and limitations of physical growth and providing solutions to basic and operational programming to develop the area of town. the method of research is descriptive – analytic and after analyzing the process of historic development in town. we analyzed effective factors and limitations in frame – physical development of town. then, the plan and programs of expanding (general and detailed plans, preparing, residence cooperatives, mehr residence and …) had analyzed in physical expanding of rasht, in last part, by preparing the information levels like as lands capability, high levels, incline, stability of land, communicational network, airport, cemetery, river, natural settlements, industry town, marsh and rural places around the city, preparing levels in arcgis software and analysis them in geographical information system and by using ahp model recognized suitable lands to develop the future of city. conclusion results show that natural and human factors and obstacles play an important role in directing the areal development of city, also it is shown that residence cooperatives, composing the surrounding villages of city around the servicing areas and informal habitation play a role in developing lf city that three mentioned factors added 4051 hectare of servicing areas during the years after islamic revelation and this number includes 40% of present area of rasht, also, findings of analytic model in ahp shows that suitable lands placed in south of town to develop the city and this lands in developing is better than other parts. suggestions 1. according to find of suitable places in southern part of city, we suggest that city foundations like: training centers, universities, medical and sport centers and other servicing places distinguished in this direction. 2. existing of many barren and loose lands in legal area of city causes the discordant development in town, so we suggest a program to operate on barren lands that hoard of profiteer motivation and to use them for owners, provide executives and technical package. 3. preparing a general and executive plan of keeping the water areas, ponds and the forest lands, also, we can use the house – garden policy in southern area (to future develop) to keep the forest and besides river areas. 4. the regulation and continuous review is for avoiding of land separation and controlling the owners of land, around the city in a way that all constructions can be in public policy of country and advance plan in rasht. 5. we suggest to create green zonal in east, north and west direction of town obstacle to dissymmetric development. reviewing in areal regulations and principles and medium and low accumulation in a way that accumulations increase about 25% legally, while in new preparation plans, there are no policy of creating villa and low accumulation houses, because of suitable usage of lands.