The World Health Organisation believes that urban green spaces are essential because of the benefits they bring to the physical and emotional well-being of people.

There are many studies that are conclusive regarding the benefits of having trees and green spaces near the home, natural spaces in which to exercise, take a walk or just sit down to read, talk or do any other activity. They are necessary for our physical and emotional health, just like drinking water, hospitals and other public services.

Their existence in the city is key for their contribution to the improvement in the health of the population. They act as “lungs” that renew the polluted air, allowing people to relax and forget about the cars and the noise, allowing them to have a higher quality of life.

The green areas and trees of the city regulate temperature, humidity, produce oxygen, filter radiation, absorb pollutants, and of course they absorb CO2, the main gas that contributes to the global warming of the planet. They also dampen noise, beautify the city, and reduce stress, in addition to being places of recreation, leisure and walking.

Urban trees allow a certain proportion of natural elements, essential for the psychic balance of people, to be kept inside cities, while at the same time improving the aesthetics of the urban landscape, creating a contrast of colours and shapes. They create a more comfortable and friendly space for the pedestrian, encouraging walking thanks to the fact that the streets become more enjoyable.

The trees are also a seasonal indicator, showing their different features in each season. People living in cities are usually surrounded by a static environment, with trees offering aspects such as colour, smell, sound, which change according to the seasons, making citizens remember the different natural cycles. Trees provide people with feelings of comfort, helping to eliminate and release nervous or emotional tensions, and contribute to their psychological well-being.

On the other hand, in the city, trees are the home to many types of birds. In fact, the number of bird species varies depending on the tree diversity of the environment. In addition to birds, trees shelter and feed a multitude of insects and small animals that are necessary for the proper functioning of the food chain and the ecosystem that they form.

Furthermore, trees are responsible for many notably positive effects such as the protection against solar rays on hot days on pavements and facades of buildings, the reduction of temperature, the force of the wind and the regulation of the relative humidity of the air. Moreover, in the summer, trees not only prevent the sun’s rays from reaching pavements and facades and, therefore, their heating, but trees also cool and moisten the air due to the consumption of environmental heat and the emission of water vapour, which is produced in the process of photosynthesis, giving a sensation of freshness, allowing the very hot days of summer to be a bit more bearable.

Being close to trees allows for the cooler days and warmer nights, since they help to reduce the differences between night and daytime temperatures.

They contribute to the improvement of air quality by reducing pollution by eliminating CO2 from the environment they use for photosynthesis. They also eliminate floating pollutants that are frequently present in the urban environment, through their foliage, which allows for the filtering of dust and particles, which are then dragged to the ground by the rain. The arboreal species also serve as a sound screen for buildings, reflecting part of the noise of automobile traffic.