A new gis procedure for peri-urban landscape change detection

This work is aimed at stimulating the adoption of advanced tools of GIS (Burrough, 1986)to improve the reading and interpreting of the territory for urban planning purposes. The basic idea is to proceed to define a suitable way to formalize and represent spatial dependent functions for territory (or landscape) qualification by recognizing, from existing maps, those themes describing, directly or indirectly, the conditioning factors. This makes possible a change detection analysis between consequent periods, permitting the planners to evaluate and quantify (both in strength and direction) the forces that drive the urban growth. According to this purpose the proposed methodology is mainly in charge of generating graphical representations (maps) showing explicitly the dynamics of the urban expansion towards the rural areas. It is worth to stress that the main goal of this work is to show how GIS approaches operate effectively in this context; it is not author’s will to face and solve the problem of which landscape quality function is the most suitable one. The one used during the tests has just to be assumed as an example useful to show how the procedure runs. From this point of view GIS can represent a useful device in the hands of the planners to make more objective their decisions and clearer their plans. This is obtained by mapping space dependent landscape quality functions whose definition is strictly related to the information derivable from existing maps. Their numerical nature permits to consider them universal descriptors.