The Necessary Integration of Green Infrastructures in the Public Transport Infrastructure Design

The spatial planning of the new infrastructures for urban mobility can provide the opportunity for the development of the urban green areas toward the condition of a healthy city. Elements such as architectural, heritage, and landscape centralities can lead to building a converging point between the two infrastructural systems of green and mobility. The development of the new urban railway lines in the city of Palermo (Italy) offers the chance to apply an integrated approach to the field. The local potentials of the biodiversity on one side and the fragmented landscape and environment systems on the other side build the framework for the development of a case study-oriented to the enhancement of the people’s health and of the environment’s ecological functions. With the aim to produce a green-blue mobility infrastructure, the study takes as founding elements the many landscape-environmental characters of the territory like historic parks and gardens (Florence Chart), EC SPA, SCI and Natural urban reserves, and the existing water networks. In particular, the comparison between the green-blue linear networks of the territory before and after modern urbanization has allowed to development of the structural map of “reconnections” as the base for the new infrastructure. Furthermore, taking into consideration the Italian regulation, the “monumental” trees have been adopted as urban pillars of the case study project for their environmental, cultural, and landscape value. The results of the study proved that the decision-making process for “fast” mobility can positively interact with the “slow” mobility systems through the landscape system itself. In fact, the landscape, characterized by an intrinsic tendency to dynamics, can be interpreted as a “landscape in motion” connecting the existing urban tissue with cultivated, natural, and historic green areas. In conclusion, key aspects such as mobility, nature, culture, and social dimension have become milestones for the integrated spatial planning process.