Written by: Ryan Nemeth
Urbanization, defined as the increase in the number of cities and urban population, is not only a demographic movement but also includes, social, economic and psychological changes that constitute the demographic movement. It is a process that leads to the growth of cities due to industrialization and economic development.
In today’s increasingly global and interconnected world, over half of the world’s population (54 per cent) lives in urban areas although there is still substantial variability in the levels of urbanization across countries. The coming decades will bring further profound changes to the size and spatial distribution of the global population. The continuing urbanization and overall growth of the world’s population is projected to add 2.5 billion people to the urban population by 2050, with nearly 90 per cent of the increase concentrated in Asia and Africa. At the same time, the proportion of the world’s population living in urban areas is expected to increase, reaching 66 per cent by 2050.
The process of urbanization historically has been associated with other important economic and social transformations, which have brought greater geographic mobility, lower fertility, longer life expectancy and population ageing. Cities are important drivers of development and poverty reduction in both urban and rural areas, as they concentrate much of the national economic activity, government, commerce and transportation, and provide crucial links with rural areas, between cities, and across international borders.
Nevertheless, rapid and unplanned urban growth threatens sustainable development when the necessary infrastructure is not developed or when policies are not implemented to ensure that the benefits of city life are equitably shared. Today, despite the comparative advantage of cities, urban areas are more unequal than rural areas and hundreds of millions of the world’s urban poor live in sub-standard conditions. In some cities, unplanned or inadequately managed urban expansion leads to rapid sprawl, pollution, and environmental degradation, together with unsustainable production and consumption patterns. I would propose that the role of green space in cities is and will become extremely important for maintenance of urban ecology and sustainable development. Furthermore, including ample green space in densely populated areas will serve as a necessary connection to our natural world.
Just as rats and other laboratory animals housed in unfit environments undergo systematic breakdowns in healthy, positive patterns of social functioning, so too do people. In greener settings such as rooms, buildings, neighborhoods, and larger areas with more vegetation, we find that people are more generous and more desirous of connections with others. In these settings we find stronger neighborhood social ties and greater sense of community, more mutual trust and willingness to help others; and we find evidence of healthier social functioning in neighborhood common space. There is more (positive) social interaction in those spaces and greater shared use of spaces by adults and children. In less green environments, we find higher rates of aggression, violence, violent crime, and property crime even after controlling for income and other differences. We also find more evidence of loneliness and more individuals reporting inadequate social support.
Access to nature, whether it is in the form of bona fide natural areas or in bits or views of nature, impacts psychological, as well as social functioning. Greater access to green views and green environments yields better cognitive functioning; more proactive, more self-discipline, and more impulse control; greater mental health overall; and greater resilience in response to stressful life events. Less access to nature is linked to exacerbated attention deficit/hyperactivity disorder symptoms, more sadness and higher rates of clinical depression. People with less access to nature are more prone to stress and anxiety, as reflected not only individuals’ self-report but also measures of pulse rate, blood pressure, and stress-related patterns of nervous system and endocrine system anxiety, as well as physician-diagnosed anxiety disorders.
Rarely do the scientific findings on any question align so clearly. While for scientists the search for greater understanding of how and why and when contact with nature impacts health continues, for society as a whole the findings are clear. Parks and other green environments are an essential component of a healthy human habitat. While street trees, parks, and public green spaces are often regarded as mere amenities; ways to beautify our communities and make life a little more pleasant. The science tells us that they play a central role in human health and healthy human functioning. Much like eating greens provides essential nutrients, so does seeing and being around green. To promote a healthier, kinder, smarter, more effective, more resilient, and a more vital populace, communities should be designed to provide every individual with regular, diverse sources of “Vitamin G.”
Ironically, just at the moment in our evolutionary history when we have turned decisively toward an urban existence with less and less contact with nature, scientists studying the impacts of the physical environment on people have discovered the importance of our connection to the natural world. In the last two decades, research on the impacts of green environments on human social, psychological, and physical health has burgeoned, and the evidence for the link between nature and human health has become so convincing that researchers have taken to using the phrase “Vitamin G” to capture nature’s role as a necessary ingredient in a healthy life (Maas, 2008). Much as nutrition scientists have discovered that fruits and vegetables play a crucial role in a healthy human diet, environmental scientists have discovered that trees, parks, and natural elements play an essential role in a healthy human habitat.
Conclusion: Protect, Interact, and Contribute to Greenspace our health and vitality depends on it!
- Kuo, J. (2010). Parks and Other Green Environments: Essential Components of a Healthy Human Habitat. National Recreation and Parks Association.
- Maas, J. (2008). Vitimin G: Green environments-healthy environments. New England Journal of Medicine, 325(24):1740-2. Utrecht: Nivel.
- Srivastava, K. (2009). Industrial Psychiatry Journal. Jul-Dec; 18(2): 75–76. Retrieved from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2996208/.
- United Nations, Department of Economic and Social Affairs, Population Division (2014). World Urbanization Prospects: The 2014 Revision, Highlights (ST/ESA/SER.A/352).