by Vittorio Compagno for this Carl Kruse Blog
This has happened to everyone. To walk on the sidewalk, surrounded by people, crammed into a curb too small for the multitude with the ongoing flow of cars to the side. Sometimes we see roadways and think maybe they are too big. We tap our ears when many cars start honking. We look constantly somewhere else when there are no trees, no vegetation around us, and all that might distract us are the billboards.
All of this is so embedded in our daily lives that we often forget this way of living is not healthy.
It’s like eating a cheeseburger every day ignoring the fact that one day it might give you a heart attack.
The death rate related to air pollution amounts to around 7 million in the world (World Health Organization), just 2 million less than the number of deaths related to cancer. But while politicians don’t act on those horrific numbers (which are bound to rise), the scientific community is growing vocal about the issue. Numerous studies indicate the positive effects that green cities have on people. You’ll be surprised to know that many of them can prevent those daunting numbers and improve our quality of life. Here are four reasons why.
Psychological Effects
Some studies have shown that being near a green area (a park, a tree-lined avenue, or a forest) can improve your mental health. In that environment, stress goes down, serotonin levels rise, and our overall wellness improves.
A research published in the “British Journal of Sports Medicine” in 2013 shows how the cerebral activity of volunteers involved was more tied to frustration and stress when the group was in an urban environment, and to relief, calmness, and relaxation when in the local city park.
In another study (International Journal of Environmental Research and Public Health), Japanese volunteers had to walk through the streets of 52 different cities in Japan for 15 minutes. The results showed increased hostility, fatigue, confusion, and depressive symptoms in the subjects. All these emotions were softened by spending the same amount of time in forests or city parks for the same amount of time.
Apparently, it’s not only the absence of chaos and noise that keeps us from having a mental breakdown. The color and the shape of trees apparently triggers in humans a positive emotional response, probably a remnant of thousands of years of evolution. In fact, trees represented for early Homo Sapiens a way to seek cover from predators, which, in early stages of evolution, was essential for survival.
Being in a park, or just around it, greatly improves mental health.
Central Park, New York
Wildlife preservation
Parks and forests are an ideal natural habitat for many species of mammals and birds. Planting more trees means also caring for the wildlife, and preserving it, since they provide food and protection for many animals. In a sustainable city biodiversity is one of the main priorities, and trees can help improve that.
Health Effects
Another important aspect of green areas for a city is not only psychological but also physiological. Research in the Netherlands indicated that living near a green area protects against many respiratory and cardiovascular diseases.
Furthermore, a paper in “The Lancet Planetary Health” grouped all of the research regarding the health effects of green spaces in cities, proving that being around parks and forests greatly reduces mortality rates. This data matches with the aforementioned WHO report, proving that the lack of trees can increase mortality and health-related issues.
For example, research published ih “Environmental Health Perspectives” analyzed a group of a million adult residents in Rome, Italy. What came out from the study was that citizens of the Italian capital had more chances to get a stroke and respiratory problems if they didn’t live in a green area. The study, conducted by the Roman Department of Epidemiology, shows that the increase in health problems in residents not living in a green area is in the neighborhood of 3%.
One of the reasons this is possible is the fact that trees produce oxygen and absorb CO2 and other dangerous gasses produced by car engines, for example. This combination allows for our blood to bring more oxygenated cells to our brain and muscles, making us effectively feel better. And that’s not their only role, since trees can greatly contribute to climate change mitigation, since those gases (along with ozone, sulfur and nitrogen oxides) are a major cause of the greenhouse effect.
Less noise and pollution
Noise pollution is one of the big problems of our modern cities. As I’m writing this article, there’s an ambulance stuck in traffic, screaming under my apartment, there are cars honking, and dogs consequently barking. The combination of these factors makes for a mess that repeats itself every day.
Cities, not mine, stay assured, have been trying for decades to dampen the noise levels only of a few decibels, occasionally failing and wasting taxpayers’ money.
Especially in poor areas, where the priorities in increasing land value are low, noise can be a daunting problem. This is a snake that eats its tail. Not only those areas are ignored in city development plans, but will also continue to be ignored because of their lower value, and so on…
On the other hand, instead of concrete and plexiglass barriers, a common solution has been simply to plant more trees. It seems that foliage greatly prevents noise, especially if they’re stopping it directly from the source.
Trees are an ideal natural barrier for sound, as they reduce noise levels not only physically, but also psychologically. Studies have shown that being detached by the source of noise greatly helps perceive it as less irritating.
Ultimately, the presence of trees not only decreases air pollutants and noise levels, but also increases property value around the area they’re planted in, making residents happier, healthier and wealthier.
Heat reduction
Another perk of green areas in cities are their heat reduction properties. It has been proven in various tests that trees can reduce air temperature as much as 5 C (9 F). That happens through a combination of shades and evapotranspiration. Evapotranspiration, alone or in combination with shading, can help reduce peak summer temperatures by 2–9°F (1–5°C). That makes trees not only beneficial for other people’s health, but also a smart investment for cities looking to counter-act the heat reduction of concrete and asphalt (technically called Urban Heath Island Effect). That is one of the biggest problems of cities like Los Angeles or Milan, and it can be mitigated through smart investments and strategical placement of trees and green areas in general.
A tree-lined street can greatly decrease temperatures, making walking easier for elders and children
Children education and entertainment
It’s been proven by research that children need access to nature and green areas. It improves their concentration, their ability to study and, overall, their mood. Motivation and attention play an important role in a student’s success, and research has found a link between those factors and the presence of green areas. It seems that not only students find more focus when around trees, but they also tend to be more attracted to studying and education in general. This is key in children that suffer from Attention Deficit Disorder (ADD) and Attention Deficit Hyperactivity Disorder (ADHD), as there is some suggestion that the symptoms of those mental states greatly decrease when around green areas.
A personal take
While cities make investments to be more eco-friendly, like electrifying the streets, or organizing waste management systems focused on recycling, there are problems that cannot be solved with economic incentives and planning. Climate change is a big problem, especially in developing countries. It’s not only local, that means that pollution produced in China (most polluted country) will find a way to Sweden (one of the greenest countries in the world) through winds. Planting trees is a local and effective solution for the climate problems of the 21st century, and especially air pollution. Cities can be greener, wildlife can be preserved, floods can be prevented with small and decentralized investments within cities. But that’s not the only thing trees are perfect for.
Mental problems have seen recent peaks among all ages. People are more stressed, introverted, and pre-existing mental conditions worse. Green areas would help a lot in this aspect. Not only parks and trees help stressed people, but they also increase the value of the land they’re planted in, making everyone happier. Furthermore, heat levels go down, more people stay in cities or visit during summer, eventually increasing the flow of money for local businesses.
Planting trees is one of the best investments that a city can do to improve quality of life, biodiversity, happiness and overall value. Soon, as climate change effects get stronger, many more administrations will see the benefits in investing in trees. Let’s only hope it won’t be too late.
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This Carl Kruse Blog homepage is at https://carlkruse.at
Contact: carl AT carlkruse DOT com
Other articles by Vittorio include A World Without Illness, Planned Obsolescence, A War Fought With Lines of Code.
Older Carl Kruse blogs are found here, and here and over here.
