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Resume Si les différents milieux aquatiques présents dans les zones urbaines sont au centre des projets d’urbanisme, ils ne permettent que peu la préservation des écosystèmes. Dans quelle mesure la mise en place de la trame bleue peu pallier à ce manque ? Comment doit-elle être envisagée ?

The various existing aquatic ecosystems in urban areas are nowadays considered as central parts of many urban planning projects but also in designing future sustainable cities. However, the consistently observed ecological degradation of watercourses draining urban land since decades limits the delivery of a range of ecosystem services and goods that benefit people’s well-being. In this context, the development of blue infrastructures in many urban areas together with urban river ecological restoration projects, can improve provision of different services thanks to an ecological condition more closely resembling streams not affected by urban land use. Locally, provision and quality of regulating, supporting and cultural ecosystem services can evolve favorably. We highlight the need to consider all identified urban natural, artificial and “hybrid” water components able to contribute to the provision of services as well as the central role of ecological engineering. Benefits from a blue infrastructure in cities will positively affect the local environmental quality, while facilitating an integrated water management.