The Green System and the Reticular Approach in the Italian Planning Instruments

During the last decades, the importance of Urban Planning’s role to safeguard green areas and to build green chains gradually increased. The latter played not only an ecological function to requalification the city’s environment quality, but it becomes also an occasion to find social space. In particular the approach changed, from a quantitative to a qualitative point of view. The first procedure reaches to achieve a minimum standard while the second one aims to satisfy ecological and environmental necessities. The overcoming of a wrong punctual approach and the use of a new reticular one has origins in territorial scope where the new model is used to maintain and improve the ecological network. The latter encourages the ecological exchanges within different natural areas, which in this way, are not converted to island, avoiding a massive loss of species, both plant and animal (Bennett, 1991; Forman, 1995; Jongman, Pungetti 2004). The transposition of the ecological network into an urban dimension led to the green chain beginning. This new model is not completely implemented by regulations even if often it has been part of the urban planning practices (Angrilli, 2002; Peraboni, 2010). In the present proposal paper a dissertation about the different approaches to the green chain is proposed. Indeed the instrumentation of Italian local planning has undergone transformations in the form and the substance: from the structure of Master Plan (PRG), planning instrument legislated by LUN 1550/42, to a new form plan carried out in Municipal Structural Plan (PSC), Urban Building Regulations (RUE) and Municipal Operative Plan (POC) and legislated by innovative laws of regional planning.