Bringing nature into cities can improve ecosystem services and local biodiversity

Cities are not just the homes of humans. They also serve as habitats for a variety of species, such as birds, insects and other animals and vegetation that have adapted to the urban environment. These species and ecosystems provide free benefits and services to people, known as ecosystem services, including cleaning water and air, providing food and aesthetic values, and giving us more healthy and liveable surroundings.

However, the world’s population is increasingly moving toward cities. Today, some 56% of the world’s total population lives in urban areas, but a United Nations report estimates that approximately 2.5 billion more people will be living in cities by 2050.

With the current growth rates, several megacities around the world could hit 30-50 million inhabitants by 2050. This rapid population growth in both large and smaller cities is putting the habitat of animals in cities and the surrounding areas under increased pressure. Consequently, there is a need to ensure that green areas and habitats are integrated into urban development and planning of cities. 

Green urban spaces are good for everyone and everything

Yet nature and biodiversity in cities are about more than just birds and butterflies, according to Carsten Fjorback, Associate Technical Director in Water and Climate Adaptation.

The green spaces that serve as habitats for different species can also help promote human health and happiness. Parks and other green recreational areas in cities provide citizens with opportunities for both exercise and relaxation, as well as contributing to noise reduction, temperature regulation and better air quality.

The World Health Organization (WHO) estimates that 7 million people die each year due to air pollution, so these greening measures could save lives. Furthermore, the green areas also serve as climate change adaptation measures by absorbing stormwater, while the trees cool the urban heat islands, and biodiversity provides biological pest and disease control.

New interdisciplinary playground

While planners, engineers and landscape architects can make important contributions toward creating areas and conditions for biodiverse cities, it is also becoming increasingly clear that trained biologists and ecologists have important roles to play. 

Rethinking the paradigm of urban development

Achieving biodiversity in an urban landscape usually requires active government intervention since commercial developers often have other primary concerns than prioritising nature first.

“At COWI, we work with a wide variety of stakeholders, such as municipalities, utilities, private companies, pension funds and others, to develop strategies and plans for unfolding biodiversity using governance,” says Katrine Grace Turner, Senior Project Manager.

She emphasises that COWI’s approach involves rethinking the paradigms of urban development, which integrates nature into the development of green spaces:

“We help urban leaders rethink their city centres to do things like manage stormwater while promoting local biodiversity. This includes using resourceful designs with native plants instead of exotic ones and a variety of habitats for all kinds of different species. With this, we are expanding the green infrastructure and creating cities where we can coexist with nature in a more sustainable way.”

Successful urban biodiversity project

One example of a successful urban biodiversity project is the newly created town of Nye, a suburb of the city of Aarhus in Denmark, which will ultimately house up to 20,000 people.

Built on a brownfield that had lost its biodiversity due to pesticide-heavy farming practices, Nye is now recovering its flora and fauna through a series of carefully designed solutions.

Nye takes special care with its water resources. Rainwater is harvested from roofs, roads and open areas and then collected in a central lake, where it is purified for reuse by households in toilets and for washing clothes. Drinking water is supplied separately from groundwater borings.

How corporate ESG goals can help biodiversity

In addition to municipalities, COWI works with large corporations, pension funds and banks that want to meet their ESG goals by prioritising biodiversity. 

“At the same time, the Corporate Social Responsibility Directive (CSRD) reporting system and the EU Taxonomy are encouraging manufacturing companies to consider the biodiversity impact of their operations. COWI’s teams help them manage that impact,” she adds.

Urban biodiversity projects work with humans

Putting together the right team to address biodiversity is a key factor in achieving successful projects that can positively contribute to urban development. 

In addition, anthropologists can help design and create biodiverse urban areas that will reflect how humans want to live together. According to Iben Fog Saxe, who is an anthropologist herself, anthropologists can add some pieces to the biodiversity puzzle by helping to create a more holistic solution:

“Part of biodiversity is human diversity, and anthropologists and sociologists can help create urban areas with attractive features, alternative forms of living and infrastructural connections that support everyday life. And while bringing nature into cities is not sufficient to save the planet’s biodiversity, it does increase our understanding of the significance of nature. Most of the world’s population lives in urban areas, and we need to understand nature’s role and value both intrinsically and instrumentally to make informed choices for the future.”