From Green Roofs to Amphibian Ponds: Building Sustainable Cities

May 2024

From Green Roofs to Amphibian Ponds: Building Sustainable Cities

With the goal of sharing how circular urban economies can operate in practice, Ann Maudsley, Johannes Riegler and Björn Wallsten, Coordinators at DUT, have gathered several cases in a recent publication Towards Regenerative Neighbourhoods: European Cases, Insights, and Initiatives.

Explore two of the cases in Slovakia and Austria, and find out 5 ways to strenghten green-blue infrastructure.  

When imagining sustainable futures, terms such as circular urban economies may represent efforts to become more resource efficient in cities. Circular Urban Economies can foster urban places, communities and neighbourhoods that not only sustain themselves but actively regenerate and enhance the well-being of their inhabitants and ecosystems.

The regenerative aspect can be understood as the way in which the urban system seeks to self-provide more resources to sustain both, society (for consumption purposes) and the ecosystems that support it (for regeneration purposes). But how can green infrastructure support establishing such systems in cities?

Green roofs can be both architecturally and functionally integrated into a building’s operation

With an area of 10,000 m², the green roofs at the Nivy Shopping Centre in Bratislava, in Slovakia, are divided into separate zones, each with its own function. For instance, to increase species abundance, the green roof uses insect houses. Furthermore, the area boasts flowers, grass beds and birdhouses. It also includes community gardens, a botanical trail and bat shelters that promote biodiversity.

In addition, the green roof area features a range of amenities including sports equipment, a barbecue area with seating and a communal garden for growing plants. Visitors can enjoy relaxation, fitness, sports, leisure, community meetings and shopping.

CUE PP Chapter 11 CUE PP Chapter 11

Examples of an insect hotel (left) and bird houses on the green roof of NIVY. 


Cities are built by humans for humans. But that doesn’t mean that we’re the only ones inhabiting those cities

A three-part amphibian welfare project near Graz, Austria, is a successful example on how to get public administrations on board in a biodiversity-focused activities. The project got support from the municipality, the federal state government, the road maintenance organisation, local farmers and residents, and the Austrian Herpetological Society (ÖGH).

“It helps when you have roots in the same town and remind people of their own childhood, when some of these species were still common. Why deprive current and future generations of a childhood rich in biodiversity, when something can be done about it at the local level?”

Gerfried Ambrosch, Award-winning conservationist

The project consisted of roughly ten new and restored amphibian ponds in three different locations a few hundred meters apart and was aimed to prop up local amphibian populations. Two years later, the project is already delivering results, facilitating toad, frog, and newt populations to fully rebound.


Prioritizing the integration of Green-Blue Infrastructure into urban planning initiatives allows cities to not only sustain life but elevate it

Engaging in activities such as gardening, strolling in parks, or birdwatching allows individuals to immerse themselves in nature, fostering a profound sense of peace and rejuvenation. These diverse experiences highlight the benefits that urban nature contributes to our physical, emotional, and psychological well-being. Two experts from the University of Regensburg shared 5 ways city planners and decision-makers can strengthen their city’s Green-Blue Infrastructure (GBI) and actualize regenerative urban landscapes:

    1. Improving Accessibility by strategically positioning both public and private green and blue areas near residences, emphasizing both vertical and horizontal greenery. In addition, evaluate proximity, vegetation coverage, and density of public green and blue spaces, refining accessibility throughout the community.
    2. Fostering Biodiversity by implementing species diversification strategies, using the morphological species approach in both green and blue urban landscapes.
    3. Maximizing Availability by integrating green networks, establishing corridors connecting homes, workplaces, and urban recreation areas for daily immersion in natural environments.
    4. Promoting Functionalities by designing versatile green-blue spaces for physical activities and water-related activities. In addition, integrate Urban Sustainable Farming, repurposing spaces like rooftops, to promote food sustainability and community involvement.
    5. Addressing Environmental Concerns by implementing features to improve air quality, reduce noise pollution, and mitigate the urban heat island effect, harnessing the benefits of GBI.


Learn more

» Explore chapters 7, 11 and 13 from Towards Regenerative Neighbourhoods: European Cases, Insights, and Initiatives

» Watch the session “Leading Change – Who and What Is Driving Urban Transitions?