The Implications and Challenges of Nature-Inclusive Cities

Is isolation from nature harming city-dwellers? The lack of biodiversity in cities contributes to ecological, environmental, and psychological challenges.

Habitat loss and pollution are among the biggest threats posed by urbanization. In fact, a research study by Dr. Brooke Williams and colleagues found that between 2000 and 2013, 1.9 million km² of untouched land became modified by humans, meaning that animals are losing places to live (Williams et al., 371). The Living Planet Index, managed by the Zoological Society of London and the World Wide Fund for Nature, finds that wildlife populations decreased by an average of 69% since 1970 (Almond et al., 4).

The detrimental effects of increasing industrialization extend to humans as well. The environment of a city itself can be unpleasant, as the “urban heat island effect” makes cities 5 to 11 degrees Celsius hotter than rural areas (Zipperer et al., 13-14). This happens due to a lack of vegetation, the prevalence of buildings that reflect light, and the geometry of buildings. The urban heat island effect increases temperatures and increases ozone production (Zipperer et al.). Additionally, cities often produce large amounts of CO₂, which “is associated with a myriad of health problems, lower life expectancy and increased infant mortality” (Castells-Quintana et al., 1).

The issue even goes beyond physical health; Ventriligo et al. found that there is a correlation between urbanization and mental health issues. Cities are often overpopulated to the point where people don’t know their neighbors, leading to less socialization. High living costs in many cities can lead to socio-economic problems, and pollution from traffic and factories leads to climate challenges. All of these factors have been correlated with increased rates of suicide, schizophrenia, and depression (Ventriligo et al., 4-7).

Inversely, living in areas that are in close proximity to nature has been shown to have positive effects on mental health. Jimenez et al. find that being exposed to nature has benefits like decreased stress levels, improved sleep quality, positive emotions, and reductions in depressive moods, among other benefits.

A straightforward solution to these challenges caused by a lack of nature would be to incorporate more nature into cities. Some cities have already attempted this, but it is not being realized at a large scale due to several factors. Firstly, the cost of maintaining green spaces in cities is high, particularly due to the cost of maintaining exotic plant species. Additionally, the fact that much of the land in cities is privately owned makes it challenging to acquire sufficient amounts of land to incorporate green spaces into cities (Murphy, 71-76).

Dr. Rob McDonald, Lead Scientist for the Global Cities Program at The Nature Conservancy, argues that there might also be safety considerations. Having large, open, natural spaces can allow illegal activity to happen “in the shadows,” as crimes could be committed by night when these places are not guarded unless restrictions are put in place, which is why many parks in cities have to close earlier in the evening (Benepe, Adrian et al.).

Despite these challenges, some cities have been able to successfully implement nature and thrive. Cities like Kodiak, Alaska are teeming with nature, but Kodiak enjoys the advantage of a more natural geography, with large mountains and wildlife just beyond the city. It’s more fair to compare modern cities to one like Portland, Oregon, which is more representative of the average northeastern American city: mostly flat and filled with tall buildings.

Portland is in Multnomah County, where CO₂ emissions were 21% below 1990 levels in 2021 according to the Summary of 2021 Multnomah County Carbon Emissions and Trends. Portland especially is taking clear steps to be more sustainable, which is reflected by its constant drop in CO₂ emissions since 2000. Their “Grey to Green” program significantly improved the city’s health, energy use, and overall livability. For example, they implemented ecoroofs, where vegetation is grown on many roofs of the city. Unlike other local governments, much of the land they choose to purchase is kept as a natural landscape; this not only improves the aesthetics of the city but also decreases air pollution. By using Oregon’s Grey to Green program as an example, many cities in the U.S. can take steps to be more environmentally sustainable.

For cities that are home to more disadvantaged groups of people, the resources to implement intricate systems like Portland’s may not be available. Studies have even shown that there is a correlation between a city’s income and the amount of green space it has (Gerrish & Watkins, 293-308). Lower-income cities therefore may suffer from pollution, increased temperatures, and flooding. However, hope is not lost for these cities to incorporate nature and thrive. As Kimberly M.S Cartier proposes in her article “Growing Equity in City Green Space,” cities can make green spaces from places like vacant lots and unused parking lots. It is most important to ensure that the community is involved throughout the process of these green projects. Citizens should be involved during the planning process to ensure that the space will be useful and beneficial to the community.

Policymakers today can take action towards improving cities by deciding to incorporate more nature, whether that be through revamping abandoned places, implementing full programs to increase biodiversity, or simply planting more trees in the city. Every case will be different and complex, but what is most important is that local governments are aware of potential challenges and community concerns. America’s nature has been deteriorating ever since the Industrial Revolution in the 1800s, and we can clearly see the effects of it in hindsight. However, it’s not too late to undo mistakes and move towards a future where we can reconnect with nature for the health of ourselves, other life forms, and the environment around us.

References

1. Benepe, Adrian, et al. “What Prevents Us from Creating Cities That Are Better for People and Nature? It Doesn’t Seem like a Lack of Knowledge-Don’t We Have Enough Research Knowledge to Act on Better Policy? So, What Is the Impediment?” The Nature of Cities, 28 June 2019, www.thenatureofcities.com/2019/06/28/what-prevents-us-from-creating-cities-that-are-better-for-people-and-nature-it-doesnt-seem-like-a-lack-of-knowledge-dont-we-have-enough-research-knowledge-to-act-on-better-policy/.

2. Castells-Quintana, David, et al. “Air pollution in an urban world: A global view on density, cities and emissions.” Ecological Economics, vol. 189, 18 July 2021, p. 107153, https://doi.org/10.1016/j.ecolecon.2021.107153.

3. Gerrish, Ed, and Shannon Lea Watkins. “The relationship between urban forests and income: A meta-analysis.” Landscape and Urban Planning, vol. 170, 6 Dec. 2017, pp. 293–308, https://doi.org/10.1016/j.landurbplan.2017.09.005.

4. Jimenez, Marcia P., et al. “Associations between Nature Exposure and Health: A review of the evidence.” International Journal of Environmental Research and Public Health, vol. 18, no. 9, 30 Apr. 2021, p. 4790, https://doi.org/10.3390/ijerph18094790.

5. Murphy, Dennis D. “Challenges to Biological Diversity in Urban Areas.” Biodiversity, National Academy Press, 1988, pp. 71–76.

6. Ventriglio, Antonio, et al. “Urbanization and emerging mental health issues.” CNS Spectrums, vol. 26, no. 1, 6 Apr. 2020, pp. 43–50, https://doi.org/10.1017/s1092852920001236.

7. Williams, Brooke A., et al. “Change in terrestrial human footprint drives continued loss of intact ecosystems.” One Earth, vol. 3, no. 3, 18 Sept. 2020, pp. 371–382, https://doi.org/10.1016/j.oneear.2020.08.009.

8. WWF (2022) Living Planet Report 2022 – Building a nature-positive society. Almond, R.E.A., Grooten, M., Juffe Bignoli, D. & Petersen, T. (Eds). WWF, Gland, Switzerland.

9. Zipperer, Wayne C., et al. “Urban Development and environmental degradation.” Oxford Research Encyclopedia of Environmental Science, 27 Aug. 2020, https://doi.org/10.1093/acrefore/9780199389414.013.97.