The role of green roofs as urban habitats for biodiversity modulated by their design: a review
Coulibaly S.F.M., Aubry C., Provent F., Rousset-Rouvière S., Joimel S.
Environmental Research Letters, 18(7)
Urban Farm DB summary
A review synthesizing existing research on how far green roofs can support urban biodiversity, framed by their design and modes of use. It finds green roofs can provide habitat for soil organisms and pollinators as well as plants, but that the effect depends strongly on design such as substrate depth and vegetation diversity, and recommends integrating soil communities into construction guidelines and increasing heterogeneity at roof and landscape scales.
Key points
- 1There is a lack of knowledge regarding green roof biodiversity, despite recent consideration.
- 2Green roofs contribute to maintaining urban biodiversity, examined through three lines of research: characterization, modes of use, and design.
- 3Studies on soil biodiversity in green roofs are particularly scarce.
- 4Green roof construction guidelines should integrate soil communities into their design and aim for heterogeneity at both roof and landscape levels.
- 5Future research should focus on diversifying and creating redundancy in rooftop conditions to increase green habitats and successful species dispersal in cities.
Direction of conclusions
Each author conclusion is recorded only as a coded direction per topic. Read the original for the conclusion itself.
- BiodiversityInconclusiveWith caveats
Abstract and stored text
OpenAlexAbstract In view of the demographic revolution and the rapid development of urban environments, the installation of green roofs could be a tool to ensure human well-being (e.g. heat island reduction, rainwater management), or to increase urban biodiversity. However, the relationships between biodiversity and green roofs are not yet clear and little research has looked into this. We therefore reviewed studies on the overall biodiversity of green roofs. Our review has shown that there is a lack of knowledge of the biodiversity of green roofs, with recent consideration. We highlighted the importance of green roof contribution, in maintaining urban biodiversity through three lines of research: characterization, modes of use and design. Furthermore, we found that there were very few studies on soil biodiversity on this topic. We concluded that green roof construction guidelines should integrate soil communities into their design and aim to be heterogeneous at roof and landscape level. Future research should focus on the diversification and redundancy of rooftop conditions in the urban matrix. This would increase the area of green habitats and the success of species dispersal in cities.
Why it matters for urban farming
This research is highly relevant for citizens planning urban farms, especially rooftop farms. It suggests that green roofs are not just for aesthetics but can function as habitats for urban biodiversity, particularly soil organisms and pollinators. When designing a farm, beyond considering soil depth and diverse plant selection, consciously integrating soil microbial communities and creating heterogeneous environments that connect with the entire rooftop and surrounding landscape can foster richer ecosystems. This provides concrete guidance for urban farms to function not just as food production sites, but as integral parts of the urban ecological network.