BIOENGINEERING AND ECOLOGICAL RESTORATION IN URBAN GREEN AREAS: EXAMPLES FROM NORTH-WESTERN ITALY

The importance of green areas is increasingly considered for the restoration of urban ecosystems. Worldwide studies concerning people needs in urban landscapes have underlined the fundamental role carried out by greening in the cities not only for social and aesthetical reasons, but also for environmental aims. Problems like soil erosion, river flooding, lack of biodiversity are frequent in urban contexts and, in the last decade, ecological planning and design methods were often applied. In particular, the application of bioengineering and ecological principles at the urban scale represents an interesting novelty. For this purpose an inter¬disciplinary approach is needed, agronomists and architects have to work together in order to solve both ecological and technical problems. Therefore, in this study authors looked at the use of bioengineering techniques in some recent interesting examples in urban green areas in Piedmont (north-western Italy). The proper employ of methods (seeding; plantations, rock walls, piling walls), materials (wood, stone, geotextiles, biotextiles) and species (grasses and herbs, shrubs and trees) were analysed. Differences from criteria used in mountain contexts, advantages and limits of these techniques in urban areas and their possible application along banks of rivers, slopes, roads, footpaths or bike paths were pointed out.