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With the rise in urban population and the urban sprawl come demand for solutions to offset the environmental burden in cities. Green infrastructures are interconnected urban spaces that provide multi-ecological functions and that mainly rely on their soils component. However, because of either the consumption of such natural resources as neighboring topsoil or the poor design and implementation of soil materials, actual approaches are questionable.Constructed Technosols, consisting of rational associations of organic and mineral wastes, are artificial soils designed to meet specific requirements. Such innovative solution based on circular economy may appear as valuable contribution to sustainable urban design. This presentation has two objectives: 1) to present the methods to create Constructed Technosols adapted for various greening purposes and 2) to present and discuss the various existing published experiences about Constructed Technosols for different land-uses (i.e. parks, street-side trees, stormwater management, urban farming, and derelict land reclamation).Our work aims at answering to the following questions: What are the main steps for the construction of Technosols? What materials and which formula should be used to design functional Constructed Technosols? What are the technical constraints to consider when using Constructed Technosols? What are the levels of ecosystem functions provided by Constructed Technosols? How fast and intense is the pedogenesis of Constructed Technosols and what are the consequences in terms of sustainability?Even though there is no optimal formula, this review provides key elements to both scientists, green spaces departments and actors involved in the management of urban soils. This review also confirms that Constructed Technosols are promising solutions for greening cities and producing potential interdisciplinary benefits for urbanites.Disclosure of Interest: None declared

International audience; Waste generation and management is a global issue receiving increasing attention. Construction and Demolition (C&D) debris generate high percentages of a country’s total solid waste, and has been estimated to contribute to 35% of the solid waste generated worldwide. Construction of Technosols is an innovative process based on the association of organic and mineral wastes to construct fertile soils that are favorable environment for plant growth. Such an approach could be a relevant solution to recycle significant amount of C&D materials as these waste could provide valuable properties such as bearing and drainage capacities and buffer capacity to the constructed Technosols. Technosols in various situations around the world are discussed as well as the actual and potential ecosystem services provided by such artificial soils. The presentation focuses on their designs and biotic choice. We explain and predict the assembly and function of Technosols under varieties of environmental conditions. Humans have total control over such soils and play a dominant role on every aspect and stages, providing a lot of opportunities. However, wrong choices can have tremendously negative consequences: every action should be weighted and evaluated carefully when manipulating these systems, to maximize Technosols ecological benefits while minimizing the ecological risk.