Modeling Urban Vertical and Horizontal Growth using Vector Cellular Automata

Rapid urbanization and urban growth are important issues to be considered. Urban development factors recognition can help urban planners and decision makers to understand the consequences of their decisions on urban growth and development .So urban planners, in order to Control the urban growth, use dynamic systems .cellular automata (CA) models have been increasingly used over the last decades to simulate a wide range of spatial phenomena.Urban development is a complex spatio-temporal process that involves both horizontal and vertical growth. Despite growing recognition of the significance of horizontal development, models of urban vertical growth remain limited .This study aims to develop a GIS-based vector cellular automata model for exploring the Horizontal growth and vertical complexities of urban growth according to the height states of existing buildings in the neighborhood and using General Development Control Regulations.The developed model has the capacity to simulate urban growth space and hence vertical growth .series of variables that are used in horizontal model including accessibility, physical suitibility , neighborhood affect and land price.Affactive factors of urban development are classified in two part: vertical variables and horizontal variables .Slope and Height factors will be used in order to calculate the phizical suitability for undevelop parcel. Euclidean distance and network distance will be used in order to calculate accessibility. neighborhood affect is considered in three component. Also Value of residential, office and retail floor area are computed for property values affect.
Vertical model was performed in two different ways. In the first method, undevelop Parcel is assigned a state value according to the height states of existing buildings in the neighborhood in which it is situated. In the second method, using General Development Control Regulations can simulate different height states of building growth. the model has been developed in a very small area of ​​the city of Qom in the years 1385 to 1394 .The results show overall accuracy 60% in horizontal growth and overall accuracy 65 % in the first method of vertical growth and overall accuracy 60 % in the second method of vertical growth .Therefore, it carries scope of being used to visualize growth for other, similar, cities and help urban planners and decision makers to understand the consequences of their decisions on urban growth and development.