A cellular automata model to simulate development density for urban planning

Most cellular automata (CA) urban models assume densities to be uniform for all cells. This is not true in real cities because densities vary substantially from city to city and from urban center to periphery areas. Development density, which affects urban form, is an important factor in urban planning. The authors present a CA model that incorporates density gradient in the simulation of urban development for different urban forms. Development density is obtained from density-decay functions and assigned to the cells when they are converted into developed cells according to CA transition rules. The model, which is based on the concept of 'grey cells', can be used as a planning model to explore various combinations of urban forms and development densities. The authors also evaluate and compare the development patterns generated by different density gradients. It is found that development scenarios with high-density development can significantly reduce encroachment on agricultural land and other important environmentally sensitive areas.