European Commission (2013) defined Green and Blue infrastructures as a strategically planned network of natural and semi-natural areas designed and managed to provide a wide range of ecosystem services. They constitute an important reference for building effective approaches to urban and regional planning if integrated in the bioregional vision. A vision that starting from Berg's founding contribution has developed in various countries and in Italy through the territorialist school of Magnaghi. The idea of bioregion is based on the co-evolutionary relationship between humans and nature which requires transdisciplinary research work. This work can refer to two key concepts: structural invariant and accessibility. The first considers natural elements and anthropic "sediments" that characterise the landscape by combining nature and culture. The second concerns the way in which human beings move and use, interact and enjoy living in a space. The fruition of the physical space, the ecological and mobility networks together with the analysis of the security perception, affordability, and beauty/wellbeing for the human beings can be understood within the green and blue infrastructures system as the structure of a bioregion. In particular, the water represents a natural resource where the nature-human interaction needs to be particularly well managed to ensure sustainable and inclusive blue and green infrastructures. The competitive uses of water and the over exploitation of water sources led to substantial negative environmental and social impacts (e.g. water shortage and seawater intrusion, flood risk, water pollution). The paper discusses the case study of the Pontine bioregion which includes all these aspects. In the Municipality of Latina, located at the centre of the Pontine bioregion, a project co-funded by the EU (Upper project-Urban Innovative Actions) aims to define a bioregional structure based on the integration of ecological networks, mobility networks and new forms of public-private partnership.

Bioregion", a term coined by Peter Berg in 1977, was improved by Alberto Magnaghi, who defined it as the space for developing new relationships of coexistence between the inhabitants-producers and the territory of a region. Therefore, bioregion is a tool for rethinking regional planning, no longer as the sum of different sectorial planning exercises, but as a "transdisciplinary planning" approach that considers all of a territory's aspects. This approach is related to EU policies for Integrated Coastal Zone Management (ICZM) and the protection of maritime and coastal areas. This paper presents a case study on the coastal areas of the Lazio region of Italy which have a great many natural areas but which is also one of the most anthropized areas in the region. Indeed, due to the rising population, many interventions in the coastal areas resulted in the transformation of natural zones into urban areas. One effect has been urban sprawl and the related lack of capillarity of the public transport network. The result was that many ecosystems and natural areas were fragmented, losing their biodiversity. With a view to reconnecting these fragmented areas, this paper discusses a new regional scenario based on enhancing the linkages between land transport networks and the maritime gateway. In this scenario, railway corridors would stimulate a new organisation for the region's settlements by representing not only the network connecting the bioregion's cities and towns but also the cornerstones for the environmental regeneration of the coastal areas.

Light rail systems can play a key role in spatial transformation processes conceptualised as urban regionalisation or new regionalism in the European Union and North America. These concepts identify new residential or micro-productive sprawled settlements which lead to ecological fragmentation, biodiversity loss, and overturn the Christallerian hierarchies without translating into an indifference to location. In Italy, the bioregional approach has been integrated into spatial planning, with the bioregional unit applied as an effective framework to analyse spatial transformation processes, with the bioregion as the main living environment, and mobility as an essential driver of lifestyle choices. After reviewing bioregional theory, the paper illustrates the characteristics of the Pontine Bioregion including the relations between urban centres and with Rome as a metropolitan hub. It then discusses the proposal of a new railway network system where the LRSs can provide benefits for efficient mobility and for urban regeneration and sustainability of the bioregion.