Green infrastructures for a sustainable urban future. The ecological structure and the greenways’ contributions

Abstract

The “Green infrastructures” are defined by a network of natural areas and open spaces considered fundamental for the ecological functioning of the territory,contributing for the preservation of the natural ecosystems, for the wildlife, for the quality of the air and water as well as for the citizens quality of life. For Bennedict and McMahon (2006), a green infrastructure consists in an ecological network that includes the environmental, social and economical components, meaning a network for the support of life.
In Portugal the green infrastructure is defined as ecological structure of the landscape or territory. According to Ferreira (2010a), such a structure recognizes the ecological systems as fundamentals and guiding elements for a sustainable implementation of the built structures, as a way to promote the biodiversity on a urban environment. The same author also refers that the definition of a greenways network, based on ecological structure is an efficient tool in the environmental requalification of unstructured territories, particularly the urban areas, allowing also an excellent basis for the definition of an urban ecological structure.
The present report discusses the green substructures, the ecological structures and the greenways networks’ contribution for the definition of a sustainable urban occupation in areas under urban pressure.