How biodiversity in cities helps humans and the environment

When biodiversity is mentioned, people picture distant, secluded rainforests that maintain the genetic wellbeing of species on Earth. However, biodiversity is applicable to many more settings than just the rainforest. In cities, biodiversity is seen when you pass by a group of birds on the way to school, when you notice species engaging with the local park, and when green architecture incorporates wildlife into human spaces.

Biodiversity is the variability among living creatures from all sources, or the genetic diversity, species diversity, and ecosystem diversity seen in ecosystems. Biodiversity is constructed from plants, animals, insects, fungi, microbes, and the ecosystems they come together to form. High levels of biodiversity are essential to health, resilience, and protection. Cities play a central part to this, too. Surprisingly, more than half of the world’s living population is located in urban areas, according to Nature. This means that cities provide high-quality habitats for some animals and overall pay an essential role to global biodiversity.

In fact, urban landscapes are becoming the last resort for some animals. The monarch butterfly is a species classified as vulnerable, and its population has been steadily declining in the last decade due to the loss of milkweed, its primary diet. However, large amounts of monarch butterflies can be spotted in New York City, one of the largest urban spaces in the world. Vox explains that New York City is a tight-knit community with community gardens, private homeowners, and roadside planting strips collectively dedicated to planting milkweed. Despite the dire loss of native milkweed in the wild, city spaces with intentional conservation efforts become a refuge for the monarch butterflies. Conversely, the development of milkweed gardens restores biodiversity and rebuild lost ecosystems for urban dwellers. Similarly, community gardens in Toronto support over 80 species of bees while Chicago is home to a thriving coyote population.

These reservoirs of biodiversity in urban landscapes are tremendously beneficial to humans. In the long term, they mitigate environmental pressures and improve resilience against climate crises, according to Nature. Furthermore, PubMed explains that biodiverse environments support better mental health and should be treated as a public health investment. Specifically, biodiversity induces the feeling of connection, lowers stress, and increases participation in recreational activities. Biodiversity does the often unnoticed job of maintaining local environments: trees filter air pollutants, roots stabilize ground soil, and vegetation reduces storm runoff.

When noticing biodiversity, do not think of it as belonging to secluded rainforests unrelated to urban life. Instead, acknowledge its impacts on vulnerable species, human life and climate resilience.