How can we transform the ‘concrete jungle’ into an attractive and healthier place for people? How can the city remind citizens of its intimate relationship with nature? How can nature and biodiversity contribute to a more energy efficient city?
Europe is one of the most urbanised continents. A large majority of Europeans live in cities and towns and their expansion increases the use of land. Urbanisation reduces green spaces in the countryside and natural areas due to urban sprawl, and within the cities themselves due to an increasing urban population.
It is time for cities to bridge the gap between urbanisation processes and the ecosystem services sustaining them. Proper urban design can reduce urban land take, have greenery penetrate the city, and turn the city into a host for significant biological diversity.
A first step should be establishing and implementing a local biodiversity strategy and action plan. This will allow urban planners and decision makers to understand the needs and concerns of stakeholders and define priorities. It will also allow them to design synergies and establish future partnerships for the implementation of the planned actions.
Municipalities can, for example, seek the creation of blue-green networks. This urban space development concept brings water management and green infrastructure together. It defines a network of existing and/or restored rivers and their valleys (blue areas) and green areas as a basis for the spatial planning of cities. From this perspective, each element of the urban green (parks, urban forests, agricultural areas, allotments, old orchards, street trees, wastelands, degraded areas and others), as well as the entire network, come together to increase biodiversity.
Blue-green networks recreate a nature-oriented water cycle. While contributing to the amenity of the city, they can combine and protect the hydrological and ecological values of the urban landscape and provide resilient and adaptive measures to deal with the impacts of climate change.
To respond to the increased pressure on open space caused by urbanisation, municipalities can also give new environmental value to derelict green areas and fringe areas. Derelict green areas are areas that have been designated as parks or natural areas but have not been sufficiently cared for and no longer provide optimal environmental value. Similarly, fringe areas are buffer zones usually located at the outer edge of urban settlements that are often abandoned or not actively managed and are most at risk of urban sprawl. Restoring and valuing these spaces provides a great opportunity to remove pollutants from soil and water, improve the habitat for wildlife, reduce the urban heat island effect and protect against soil erosion and floods, while offering new recreational green areas for residents. Some European city authorities – such as the London Borough of Tower Hamlets and Barking and Dagenham (UK) and the City of Almelo (The Netherlands) – have already restored areas with different characteristics into natural areas with recreational value. Take the opportunity to learn from their experience.
The deployment of green roofs on buildings can also be an element of a biodiversity strategy and can even contribute to effective blue-green networks. Besides being hospitable to plant and animal life, green roofs can also help to reduce the energy demand of the building, improve water quality and host renewable energy systems. If kids in your city have never picked fruit directly from a tree, they may do so in the future from a tree planted on a roof.