Greener cities are healthier cities.
When you think of big cities or metropolises, the first images that come to mind are buildings, cars, lots of people, and crowds. But, when thinking specifically of big cities like New York in the USA or Barcelona in Spain, both considered cities with a high HDI index, other images also pop into mind, images of large green areas like Central Park in New York or Parque de la Ciutadella in Barcelona.
“Cities should have between 10 and 15 m2 of green areas per inhabitant”
Knowing the importance of green areas, the WHO (World Health Organization) calculated that cities should have between 10 and 15 m2 of green areas per inhabitant. Based on these calculations, the city of São Luís – MA, for example, with 1,094,667 inhabitants, according to the latest survey by the Brazilian Institute of Geography and Statistics (IBGE), should have between 109 and 164 hectares of green areas.
There are several possible definitions of what a green area would be, but according to the National Council for the Environment (CONAMA), a green area in the public domain is considered “a space in the public domain that performs an ecological, landscape and recreational function, providing for the improvement of aesthetic, functional and environmental quality of the city, being endowed with vegetation and spaces free of waterproofing”.
But why are green areas considered so important even for the World Health Organization?
Let’s look at some examples:
1. Helps in combating contamination
Green areas can be considered true lungs that help clean up the typical atmospheric pollution of large cities, through the absorption of CO2 and other polluting gases.
2. Rainwater retention
The soil covered by vegetation and not waterproofed by concrete works like a real sponge that helps to retain rainwater. At the same time that they serve to feed the vegetation itself, they also help to supply groundwater and reduce flooding, frequent problems in many large cities.
3. Improvement in people’s physical and emotional health
Green areas are proven to reduce stress. Through the connection with nature and the contemplation of the landscape, it is possible to increase the feeling of relaxation, increase creativity, reduce anxiety and even increase affective capacities. While helping mental health, it also allows people to exercise and practice outdoor sports, also improving physical health.
4. Stimulates people’s social relationships and environmental awareness
Many studies show that green areas help in social relations as they foster a sense of community when they allow the practice of outdoor activities by the city’s inhabitants. And as a positive consequence of this stimulation of community integration and feelings, studies also show that good social relationships reduce mortality levels, suicide rates, and increase long-term health levels. Contact with nature, present in these green areas, is one of the best ways to make us more aware of the importance of taking care of nature. All studies confirm that the most effective way of creating ecological awareness and being able to experience nature and contact with it is essential for us to be concerned about taking care of it.
Helping to reduce heat islands, preserving regional ecosystems, and helping to generate mosaics of biodiversity fragments in urban areas are some of the many other benefits that we can go on talking about.
Unfortunately, it is very difficult to monetize all these benefits that green areas bring to cities due to the integration and relativization of various factors and the consequences of these factors. But today it is already possible to estimate with some acceptability how economically these green areas are important. In the US, for example, an assessment of the nation’s 85 largest cities, with a population of around 57.2 million, found that parks help save around US$3.08 billion in healthcare alone. In the city of Philadelphia, also in the USA, savings of 16 million dollars were verified as a result of the management of stormwater and the reduction of pollution caused by the good management of green areas, according to the report Trust for Public Land Center for City Park Excellence.
Even knowing the importance of green areas in urban areas, the loss of green spaces is proportionally greater than the creation of new spaces, since the loss of private green areas is rarely compensated by the provision of more public green areas.
Faced with this challenge, another study conducted in two cities, one in Australia (Brisbane) and the other in Japan (Sapporo) designed a new technique for rapid assessment of unused areas or areas that are “left over” in cities and that could serve to create of green areas, areas named in the study as Informal Urban Green-Space (IGS). In this study it was demonstrated that in these two cities that IGS can substantially increase the amount of green areas in cities.
Like New York, Barcelona, Philadelphia, Sapporo and many other cities that know the importance and value of green areas, many cities can and should see green areas as an asset capable of not only helping to conserve biodiversity and improve the quality of life of the local population, but also help in the health economy of many millions. We at IBPBio work towards the elaboration and execution of projects that can make the reality of the cities above also our reality. Green in the city is to live better!
Do you want to know more about our projects for urban green areas? Contact us!
