The morphological constraints of the settlement growth/degrowth processes. An interpretation of the concept of territorialisation cycle

In many geographical areas, the demographic transition has led to a situation of relative stability of urban and regional settlement. The phase of rapid population growth that generated the urbanization process has stabilized. In these conditions of stability, however, arise very complex dynamics in which growing paths alternate with decreasing periods and urban regions. In a context of strong competition between cities and urban regions, a general selective phenomenon of use /reuse / abandon is observed. Resuming the theories of territorialisation cycles (Muratori, Caniggia, Cataldi) it is possible to propose an interpretation of the history of the territory as a succession of cycles. Both the economic and geographic models and the morphological models allow us to grasp those interesting allometric relations between cities and urban systems that characterize the different development cycles. The aim of the paper is to analyze the long-term urban plan for the territory of Albenga area (Liguria, Italy. Settlements are analyzed together with the basic territorial structures that have generated them during the historic long period. The study starts from the diachronic reading of cycles of territorial development that have gradually formed the present settlement. An important role is played by the morphological conditions in which the growth/degrowth process takes place. Given that these dynamic change phenomena occur in territories where previous settlement development processes had determined specific morphological conditions, it is hypothesized that the role played by morphogenetic phenomena of selective reuse /abandon (studied through morphological models, such as cellular automata) is of great relevance.