The green city is a key element of the built environment in relation to the landscape.
The anticipated spread of urban green, also given by Agenda 21 and the Aalborg Charter, is a matter of great importance for improving the quality of life in cities. E 'but needed careful assessment of some of its characteristics, in order to improve its function and to facilitate the arrangements for its management, as well as to allow rational planning of expansion of green areas. This should, in maximum number of Common (and not just the larger ones) to the municipal development plan (PUC) was functionally complemented a Plan of urban green, a concept paper now rarely used, the absence of which produces a significant waste of public money and fact makes it less usable green for the citizens.
Anglo-Saxon countries the discipline that is concerned with the urban green spaces is known as the Urban Forestry, (literally: "urban forestry"), as if to indicate how green spaces can offer itself as an oasis of rural areas within the city, with a focus on the wilderness green areas in a "dry" built.
With specific reference to cultural models of sustainability in urban areas and the role of green inside the city could be significant discovery - at least in urban areas, less damaging, but also and especially in the bigger centers - urban vegetable gardens, which are the subject (especially overseas, where we talk about urban agriculture) of a movement of revival of agriculture self-made, fully in line with the objectives of Agenda 21. The urban gardens have been part and parcel of Western architecture with so-called Garden City, discontinued over a little over a century by a few generations of architects and engineers modern (and more generally from a culture of building and industrialist ' urban) that have focused on the brick and concrete rather than the elements of inclusion and enhance the environment (including urban), erasing a cultural element present in European cities since the Middle Ages.
It should also highlight the vital role of the Green bioclimatic point of view, because the evapotranspiration produced by plants may contribute to a significant mitigation of the summer temperatures in urban areas.
