Green roof habitats

Green roof: habitats facing climate change and biodiversity crisis

Green roofs are considered an important element of climate-friendly cities and can improve the quality of life. In the Sparkling Science project “Green Roof Habitats”, scientists from the Departments of Ecology and Botany at the University of Innsbruck collaborated with high school students and teachers to investigate the potential of green roofs in the Alps to increase biodiversity.

For this, green roofs in Innsbruck, Dornbirn, Vomp, Kleinwalsertal and Allhaming were surveyed over 2 years and compared with meadows and sealed areas. The project investigated how plants and insects survive in the extreme conditions on the roofs, and how green roofs can be optimised to provide diverse habitats despite heat and drought periods.

Close collaboration with teachers, students and citizen scientists was a pivotal part of the project. Over the course of two years, 159 participating students from seven classes participated in 20 workshops with the scientists involved, learning about ecological relationships and scientific work, and conducting hands-on research in the area around their own schools. The collaboration was rewarding for all groups involved. Besides providing a comprehensive database on the ecology of green roofs in the Alps, it fostered an understanding of science and environmental awareness as well as a sense of self-efficacy. An organised science festival gave the participating students the opportunity to present the results of their own research projects, enabling lively exchange between the schools involved. During the Citizen Science Award 2024, for which the project was selected, 155 participants, mainly school students, mapped over 6,000 green roofs in Austria.

The study results show that green roofs provide habitats for plants and animals that are adapted to extreme conditions. Recurring droughts and soil temperatures of up to 48 °C require special adaptions of the species living there. Nevertheless, more than 2,000 insect species were detected on most green roofs using insect traps and modern genetic methods. Currently, only a portion of these species have a known species name related to their genetic code, as the relevant identification databases are not yet complete. However, these databases are continuously being expanded. Among the observed species were some that are new to Western Austria. Providing areas with different substrate depths and additional structures such as dead wood, as well as using regional shrubs for greening, can increase the biological diversity on roofs. In summary, the results show that green roofs can contribute significantly to biodiversity, particularly when they are designed with diverse structures. The project´s results were published in multiple scientific journals. Through contributions on TV, radio and print media, as well as public events, the project reached a wide audience and raised awareness for the importance of biodiversity and green roofs.

This project is already completed.