Vegetable rooftop at AgroParisTech

The Bertrand Ney roftop at AgroParisTech (Claude Bernard site) was the experimental site for Baptiste Grard’s PhD thesis project until 2017. His research work aimed to study, from a physical, chemical and biological point of view, rooftop culture systems based on technosols (i.e. soils reconstituted by humans from materials of anthropogenic origin) composed entirely of urban residues (compost, brick, mushroom farm residue, etc.), in order to better understand the evolution of their characteristics and their effectiveness in providing a certain number of services over time. Within a green roof, technosol is in fact the basis of most of the ecosystem services provided, including that of food production. It is therefore a key point in the sustainability of productive rooftops that are built from recycled materials.

The PhD thesis also aimed to assess the ecosystem services provided by a productive rooftop of this type. The goal was to provide the tools and knowledge necessary for their implementation as part of the sustainable development of buildings in an urban environment.

Thomas Haden, Research Engineer, was recruited in 2018 at AgroParisTech for a one-year fixed-term contract during which a new phase of experiments was launched with new urban organic waste products. 15 tonnes of old substrates had to be evacuated while around ten tonnes of new substrates and material were delivered. In total, about fifty boxes were reconditioned in order to conduct various experiments until 2021.