A Yellow Suitcase, A Greener Perspective
Almost four years ago, I packed my life into a large yellow suitcase and moved to the Netherlands leaving behind one the most famous peninsulas on the globe. From the beginning, I noticed meaningful differences in how life and society are structured. One of the most striking contrasts emerged in how public and private green spaces are designed and perceived. In the Netherlands, biodiversity isn’t an afterthought. It’s woven into the urban fabric: tram shelters with green roofs, wild grasses growing between tram tracks, flower-rich gardens that look unkempt but are intentionally allowed to flourish, and even bug hotels and worm shelters integrated into parks and neighbourhoods. Moreover, public consultation, including referenda, regularly places the expansion of green areas on the political agenda.
Over time, these elements became my new normality.
It wasn’t until I returned to Italy last spring that the contrast truly hit me. In my childhood neighbourhood, the park where I used to play had been replaced by concrete. All around, the gardens were highly manicured: grass trimmed to the centimetre, no wildflowers in sight, and a design aesthetic that favoured control over creativity, symmetry over spontaneity. They were beautiful in the classical sense, but ecologically silent.
This dissonance sparked a deeper reflection on what cities do to nature. Urban development, by its very structure, fragments ecosystems, like removing pieces from a puzzle box. These gaps disrupt the continuity of habitats, making it harder for species to thrive.
We can not undo urbanisation, but we can redesign our cities to become part of the ecological network, not separate from it. It’s about creating climate-resilient, healthier, more liveable spaces, for people and all forms of life.
Why Urban Biodiversity Matters
Urban biodiversity refers to the variety of plants, animals, and microorganisms living within city environments. Its importance extends far beyond aesthetics, it forms the backbone of healthy ecosystems and human well-being. One critical role of biodiversity is supporting ecosystem services such as pollination, a process essential for the reproduction of many crops and wild plants. In fact, over 75% of global food crops rely on animal pollinators, including bees, butterflies, birds, and bats (IPBES, 2016). Without these species, food security would be severely threatened.
Moreover, biodiversity enhances urban resilience by contributing to climate adaptation. Vegetation like trees, shrubs, and grasses reduce the urban heat island effect by cooling surface temperatures and providing shade. They also improve air quality by filtering harmful pollutants and capturing carbon dioxide. Natural soils and permeable surfaces allow rainwater to infiltrate, reducing flood risks during heavy storms (Eicker, 2018). These ecological functions form natural infrastructure that protects cities from climate-related stresses.
Equally important are the social and health benefits of biodiversity. Access to diverse green spaces has been linked to lower stress levels, improved cognitive function, and increased opportunities for social interaction. Research suggests that exposure to varied plant and animal life can boost the immune system, an effect demonstrated in children attending daycare centres with biodiverse outdoor areas, who developed stronger immune responses within just one month (Roslund et al., 2020). Moreover, evidence from a systematic review by Marselle et al. (2021) indicates that biodiversity-rich urban environments can significantly reduce anxiety and improve overall psychological well-being, with the variety of plant and animal species playing a key role in these benefits. Such environments may facilitate mental restoration by offering sensory richness and opportunities for nature connection, both shown to buffer the effects of stress.
Urban biodiversity thus supports both environmental sustainability and human health, making it a fundamental pillar for thriving cities.
Cities Taking Action: From Grey to Green
Around the world, cities are beginning to reimagine what urban life could look like when nature is allowed back in. Paris, for example, has launched one of Europe’s most ambitious greening strategies, removing over 70,000 parking spaces to make room for trees and green corridors. By 2026, the city plans to plant 170,000 trees as part of its “Plan Arbre”, aimed at reducing the urban heat island effect and improving biodiversity.
Berlin has integrated ecological thinking into its planning for decades. Its “Biotope Area Factor” requires new developments to include green roofs, permeable surfaces, or habitat features. This policy ensures that even in a dense capital city, nature isn’t pushed aside but incorporated into everyday architecture. Amsterdam, too, is restoring natural connections by expanding its network of green corridors, planting native wildflowers along tram lines, and even installing insect hotels in public parks.
Beyond Europe, other cities are leading with creativity and urgency. Singapore, often called a “City in a Garden”, has woven green walls, rooftop forests, and vertical farms into its skyline. Nearly half of its urban area is green space, and its park connector network allows both people and wildlife to move safely across the city. In Melbourne, Australia, the city’s “Urban Forest Strategy” has increased canopy cover and led to measurable improvements in cooling, air quality, and habitat diversity.
These initiatives are more than beautification. Scientific studies have shown that even small patches of native vegetation in urban settings can host even hundreds of insect and bird species (Goddard et al., 2010; Aronson et al., 2017). Urban biodiversity is not a luxury. It is an essential foundation for building cities that are healthier, more resilient, and more equitable in the face of climate change.
Planting seeds of change
Transforming our cities into thriving ecosystems may seem like a daunting task, but real change often begins in small, humble ways. During my recent stay in Italy, I was deeply struck by what I saw. That experience prompted me to act.
I started a small project: I placed a sign on the fence of our family garden, an intentionally wild, diverse patch of green that might appear messy to some. The sign explained that our garden wasn’t abandoned or neglected. On the contrary, it was carefully cultivated to support biodiversity, to welcome pollinators and shelter small life.
Now, even though I’ve returned to the Netherlands, my parents tell me that passersby often pause to read the sign. Some stop to ask questions, others simply express curiosity or gratitude. These conversations, small as they may be, are reminders that people are not indifferent. Often, they’re just not informed.
Urban biodiversity is not only about plants and animals, it’s also about people. We can help biodiversity thrive in cities through our choices and actions, and we benefit from it.
It’s about reimagining our daily environments in ways that are healthier, more resilient, and more connected. While the mission is undeniably broad, each garden, each flower bed, and each informed conversation plays a part. The goal is not perfection. It’s progress, and progress begins with awareness.
If we provide people with the tools and knowledge to care, they often will. Sometimes, all it takes to plant the seed of change is a sign on a garden gate.
References:
Amsterdam Municipality. (2020). Sustainability report 2020. https://www.amsterdam.nl/en/policy/sustainability/
Aronson, M. F. J., Lepczyk, C. A., Evans, K. L., Goddard, M. A., Lerman, S. B., MacIvor, J. S., … & Vargo, T. (2017). Biodiversity in the city: Key challenges for urban green space management. Frontiers in Ecology and the Environment, 15(4), 189–196. https://doi.org/10.1002/fee.1500
Berlin Senate Department for Urban Development and Housing. (n.d.). Biotope area factor. https://www.stadtentwicklung.berlin.de/umwelt/landschaftsplanung/bff_en.shtml
City of Melbourne. (2012). Melbourne urban forest strategy. https://www.melbourne.vic.gov.au/community/parks-open-spaces/urban-forest/Pages/urban-forest-strategy.aspx
City of Melbourne. (2021). Urban forest strategy – Making a great city greener.
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