Key Takeaways:
- Our built environment has a large impact on biodiversity, and our current “take-make-waste” model puts biodiversity at risk
- We are currently facing the consequences of decreasing ecosystem services, ecological degradation, and inequitable access to nature in cities across the globe
- Incorporating sustainable built environment solutions like environmental restoration projects and individual actions can help our wild neighbors thrive
Who are we building for?
Have you ever seen a wild animal in an urban setting, curious about where it came from in a city with such little green space? It’s easy to think of nature and cities as complete opposites, but the lines between these spaces are growing thinner each day as our built environment expands. The term built environment is commonly used in the world of sustainability to describe the many aspects of our man-made environments. According to a World Bank report, over 50% of the human population currently lives in cities, and this number is growing every day. With increasing urbanization, our built environment is expanding into natural ecosystems and habitats of many native organisms surrounding cities.
According to the US Environmental Protection Agency, the built environment includes the “buildings we live in, the distribution systems that provide us with water and electricity, and the roads, bridges, and transportation systems we use to get from place to place”. So where does maintaining and conserving biodiversity currently stand in our built environment? Well, it’s extremely low on our list of priorities in most cities. According to the nonprofit Ellen MacArthur Foundation, the built environment “currently operates under a take-make-waste model that puts significant pressure on biodiversity”. So how do we incorporate sustainability into our built environment? A sustainable built environment considers circularity, longevity, flexibility, assembly, disassembly, the use of healthy materials, and the health of ecosystems, but we have a long way to go until all cities support this.
What consequences are we currently facing?
As we create systems and structures in our built environment, we are building on top of organisms and their homes, forcing many species to suffer from habitat fragmentation, higher wildlife mortality rates, and forced human-wildlife interactions. On top of this, biodiversity loss does not only affect ecosystems, but humans as well. Ecosystem services represent the value we place on nature through their economic, recreational, and biological benefits. This can include providing lumber and building materials, clean air and water, fertile soil for crop production, pollination, and flood control. The value of ecosystem services currently stands at $44 trillion, over half of the global GDP. According to GRESB, the global ESG benchmark for financial markets, the built environment is currently responsible for nearly 30% of global biodiversity loss. This is causing a catastrophic impact on our ecosystems and the services they provide. To take a closer look at how our current systems are failing biodiversity, we dove deeper into the events currently taking place in Mumbai, India.
Mumbai: A Case Study
Mumbai is one of the most densely-populated cities in India with an estimated population of over 20 million residents. Today, it stands at a critical point in history as its rich ecosystems and unique biodiversity are under threat due to industry-centric urban planning and rapidly growing emissions. According to NPR, Mumbai lost nearly 40% (~ 9,000 acres) of its mangroves between 1991 and 2001. This is due to increasing infrastructure projects that destroy habitats and large amounts of garbage, plastic, and waste that get dumped into the sea, acting as an oxygen vacuum that suffocates the plants and destroys the soil. The rapid decline of mangroves has created a multifold impact on the city, leading to many issues due to an overall decline in ecosystem services. So what services is Mumbai losing as the mangroves disappear?
The Mangroves are the verdant coast guards of Mumbai and form an integral part of the city’s biodiversity. These mangrove trees are vital to the ecosystem, providing the following regulating and supporting ecosystem services:
- Acts as an effective carbon sink
- Prevents coastal erosion and saltwater intrusion
- Provides breeding, spawning, and nursery habitat for marine life
- Protects coastal homes from floods and storms
- Provides green cover, which reduces the effects of urban heat islands
- Creates a natural aesthetic that has defined the landscape of Mumbai for generations
Without these ecosystem services, the citizens of Mumbai are suffering from catastrophic flooding and are beginning to see a cascading effect on their economy. Fortunately, many environmentalists living in Mumbai refuse to sit back and watch their mangrove forests die. Activists are organizing exhibitions and using their collective voices to expose the negative environmental impacts that infrastructure projects are causing. In an NPR interview with activists, they shared their motivations, expressing:
“We are not against any development. Our question is, does it need to happen at the cost of the environment?”
Invasions and nature inequities
While most cases of urbanization result in a loss of biodiversity and ecosystem degradation, it is also worth noting that some species thrive in our built environment. I spoke with the Hall Lab at Arizona State University, a team of conservation biology researchers who explored ecological patterns and processes in human-dominated ecosystems, to get more insight into such cases. Graduate students Alexandreana Cocroft and Jeff Haight explained:
“Some species adapt to urban areas and exploit anthropogenic food sources and the lack of predators… Increasing development of natural habitats has driven many species into highly populated urban environments, even though these species would usually avoid them.”
Hall Lab, ASU
Thinking of our current “take-make-waste” model, it makes sense that generalist species are able to exploit copious amounts of food waste and lack of large predators in our built environment. Wildlife can be forced to live in urban areas as their habitats are built over, and this can lead to many issues for wildlife and urban residents. Human lives and property, as well as the lives of wild animals, are being harmed by forced interaction, and this is becoming a growing issue in urban areas. It is also common that as generalist species grow and become invasive, they can cause native species populations to suffer.
According to Hall Lab’s research on the socio-ecological dynamics of residential landscapes, “lower socio-economic status residents in urban areas tend to be more exposed to environmental disservices.” The intensity of these issues varies per city, nature inequalities in low-income communities tend to follow a pattern, consisting of:
- More intense urban heat island effects
- Less tree canopy cover
- More air pollutants
- Less access to high-quality, safe green spaces
Patterns across the country show that quite often vegetation and biodiversity seen in urban areas positively correlate with income. Hall Lab mentions, “these patterns have likely been attributed to a combination of human preferences as well as lasting effects of discriminatory housing practices in which lower socio-economic status residents experience more densely populated neighborhoods and more environmental disadvantages”. When environmental and social inequities are present, low-income residents miss out on important wildlife connections, and this can lead to negative associations with nature, wildlife, and conservation issues.
“Specifically in the Phoenix metro area and in our research in the Hall lab, we are observing that underserved neighborhoods with a high proportion of non-White residents tend to see fewer native wildlife species… resident’s perceptions of wildlife are often related to social factors such as familiarity with nature and proximity to risk, social vulnerability, education level, and environmental worldviews.”
Hall Lab, ASU
With growing socio-economic injustices and environmental disservices in urban areas, the presence of negative relationships with common urban animals continues to grow. Circling back to the issues of Mumbai’s built environment, species such as city pigeons have caused noticeable problems for urban residents. Pigeons are considered a major nuisance and are commonly listed as an invasive species in many dense urban areas. Many people complain about the waste and unsanitary conditions that correlate with large pigeon populations. Pigeons are heavily infested with parasites such as fleas and mites and are known to transmit ornithosis, encephalitis, and salmonella food poisoning. According to an article published in Times of India, “the largest number of allergic pneumonia cases in Mumbai were related to pigeons… as pigeon droppings contain antigens which when inhaled trigger an immune reaction in the body which can cause lung fibrosis” and if not treated properly, can be life-threatening to humans.
The success of urban pigeon populations revolves around the fact that they are generalist species, and the Mumbai municipal corporations are not doing enough to tackle the problem, especially for the low-income communities that are suffering the worst of poor waste management where pigeons tend to flock to. Across the globe, cities such as New York City are using new sanitation and waste management systems to reduce pest problems, noticeably with rats scattered throughout the city. In order to solve these issues, it is necessary to assess these patterns and the drivers behind them to increase the well-being of residents. Proper action taken by local governments is needed to address the disadvantages lower socio-economic populations face to promote positive human-wildlife interactions and increase interest and action in conservation issues.
Seeking bio-centric solutions
By planning for compact and biodiverse urban environments that optimize space, our built environment can leave room for nature to thrive within and beyond urban areas, as emphasized by the Ellen MacArthur Foundation. But how are we going to completely transform our cities and urban areas to protect biodiversity, ecosystem services, and nature equity? Fortunately, as the effects of urbanization are becoming bigger and more pressing each year, urban areas are adopting more sustainable solutions. Arizona Game and Fish Department (AZGFD) is one of the many organizations implementing these innovations, namely with their wildlife connectivity projects. We met with biologists from the Arizona Game and Fish Department Wildlife Contracts Branch, where they gave us insight on such solutions:
“Wildlife connectivity describes the facility for animals to move across the landscape. In our perpetually growing built environment, habitat fragmentation occurs, in which contiguous habitat is disconnected by infrastructure, agriculture, or other anthropogenic features. Maintaining connectivity through wildlife corridors and wildlife linkages is important as they allow species to move between otherwise fragmented, isolated habitats to maintain ecological processes.”
AZGFD Wildlife Contracts Branch
In their current projects, AZGFD is creating crossing structures throughout main roadways and conducting movement studies and road mortality surveys to see the benefits of increased connectivity. Through their research, they have found that maintaining connectivity has a number of benefits, such as:
- Promoting genetic diversity
- Allowing isolated populations to move in order to access the resources they need to survive
- Expanding wildlife home ranges
- Helping wildlife find mates and raise young
- Preventing fragmentation and wildlife-vehicle collisions in existing infrastructure
The Sonoran Desert Conservation Plan (SDCP) is another example of mandating regional-scale conservation of biodiversity in the built environment development process. While each city, country, and neighborhood requires a unique approach to conservation planning based on social and political context, the SDCP provides a great example of planning for biodiversity in cities through coordination across multiple cities and jurisdictions (as wildlife does not respect municipal boundaries!). Environmental leadership is also a very important part of projects like this, and having a community of organizations that share concerns and provide support for environmental protection is crucial for making a real change in our sustainable built environment.
State and local governments, environmental NGOs, and nonprofits across the globe are promoting biodiversity restoration and conservation projects like these in order to implement change in city management of biodiversity. To learn more about solutions these organizations are implementing around the world, check out Food and Agriculture Organizations of the United Nations’ Forests and sustainable cities: Inspiring stories from around the world.
Make room for your wild neighbors
Curious about how you can make a difference as an individual? Every voice matters! These suggestions give people a say in how their built environment is developed while prioritizing biodiversity protection.
- Practice ecological landscape design. Make the area around your home a comfortable and safe space for critters, while also creating environmental benefits. Consider growing native plants that create an important foundation for ecosystems to thrive. If you have a grass lawn, incorporate native seeds throughout and allow the space to grow naturally, or consider redesigning your yard to account for native climates, such as xeriscaping in desert cities. Making sure your yard has native plants is essential; invasive species may consume more water than is available in the area you live, start wildfires, ruin soil health, and compete with native plant species.
- Get involved in volunteer work. Many cities have clubs or organizations that promote environmental services in cities. Whether this involves keeping your local parks clean, building habitats for urban wildlife, planting native plants, or providing environmental education, your actions can influence change in how we consider biodiversity in our built environment.
- Advocate for pro-biodiversity policy-makers. One of the most critical things individuals can do for biodiversity is to advocate with local policy-makers and vote for city, county, and state officials who share their pro-biodiversity attitudes. We must also be engaged in the local city council to shed light on the issues with our current built environment to show representatives and stakeholders that we care about biodiversity. Sharing ideas such as creating more new green spaces, especially in areas that lack green spaces, can create more equitable access and promote a connection to nature. Use your voice to promote change!
Our built environment has a big impact on biodiversity, and if we do not consider how our current systems are harming biodiversity, we will continue to face the consequences of decreased ecosystem services, ecological degradation, and inequitable access to nature in cities. Implementing solutions such as environmental restoration projects and individual actions will allow for our built environment to continue to develop and grow with the future of people and our planet in mind. We must use our voices and actions to promote change, learn about the issues in our built environment, and work together to implement solutions.
