Évaluation des performances écosystémiques d’une renaturation du milieu urbain
Urban areas are facing a broad range of challenges due to unsustainable urbanization, degradation of natural capital, as well as an expected increase in intensity and frequency of extreme weather events due to climate change. This should directly exacerbate the environmental consequences (stormwater management) or indirectly (urban heat island and biodiversity degradation) related to the water cycle. Blue Green Solutions (BGS), such as green roofs or vegetated swales, are particularly efficient to reduce the potential impact of new and existing urban developments with respect to these issues. Although BGS benefits are perceived, promoters are still reluctant to implement them (or only on aesthetic considerations). Some methodologies and tools have therfore to be developed to better understand the thermo-hydric behaviour of such infrastructure in relation with biodiversity, and to assess their performances through scales (from the constituent material to the development project).
The four years EVNATURB project aims to develop an operational platform to assess some of the eco-system services (ie stormwater management, cooling effect, or biodiversity conservation) provided by BGS at the district scale, and to promote the re-naturation of cities. It will be intended for every stakeholder involved in urban development projects (planners, architects, engineering and environmental certification companies…) and will help them to implement BGS and evaluate which ones are the most appropriate for a particular project depending on its environmental objectives and constraints, and particularly for obtaining environmental certification.
To address the wide and complex issues related to this topic, EVNATURB intends to put an emphasis on an interdisciplinary, multi-scale and multi-physics approach to:
- Couple hydrology, thermic, urbanism, biodiversity and the corresponding eco-systemic services;
- Characterise the spatio-temporal variability of the related processes over a wide range of scales by (i) the implementation of a complex, portable and high-resolution monitoring, and (ii) the use of adapted analysis and modelling tools;
- Develop a scientific network devoted to BGS monitoring and contribute to expand knowledge and fulfil the lack of feedback concerning the functioning of existing BGS;
- Characterise the implementation of BGS infrastructures by taking into local socio-environmental stakes and constraints, and define some quantitative indicators relevant for the development project (certification, labelling, compliance with local regulations, continuity with surrounding biodiversity, etc.).