Urban greenery: how, where and why it is not enough

There is no longer any doubt about the undeniable need to surround ourselves with plants to counteract climate change. After all, planting trees is considered the most natural and healthy way to contain global warming. But while reforestation is talked about a lot, and while it is much easier to come across in meadows and gardens in peripheral or rural areas, what is not talked about enough, but is incredibly useful, is so-called urban greenery.

Also known as public greenery, it refers to the collection of small and large spaces within metropolitan areas dominated by nature. A counterweight to the scorching and rough asphalt and the heat from the combustion of motor vehicles, urban greenery is a weapon that should not be underestimated in the fight against pollution and climate change. And, in fact, not only that, because its qualities do not stop there.

1. Where to find urban greenery
2. Trees in the city as an essential ecological service
3. What is the situation today?

Where to find urban greenery

When we hear about urban greenery, the first thing that comes to everyone's mind are those tree-lined medians in the center of the roadway, which divide the two lanes of suburban streets with palms, cypresses, plane trees, and oleanders. Those spaces dedicated to trees may steal a little space from the lanes and do not help to decongest traffic, but they undoubtedly help the livability of cities.

These avenues, which certainly do their part, are not by any means the only examples of urban greenery worth noting. The most obvious are undoubtedly the parks, the municipal villas, and all those spaces that somehow offer not only a lot of greenery, but also cool and traffic-free places to gather.

Flower beds, trees along the sidewalks, and the romantic and characteristic typical tree-lined avenues of the best-kept and most commercial areas of large cities also contribute to the urban greenery quota. Of course, to fill metropolitan areas with so much greenery, a lot of space is needed, which is very difficult for the most densely populated areas. But a national program dedicated to this purpose would be essential to make even the largest and most polluting cities more livable, healthier, and more eco-friendly.

Trees in the city as an essential ecological service

Cities deal with much more than just one pollution problem. The smog we imagine to be the greatest threat to the health of urban areas is only a small drop. In the annual report that the National Environmental Protection System periodically draws up, several types of pollution are discussed. From traffic that contributes to very poor air quality, to the noise pollution typical of densely populated and busy areas, to heat islands. This is a phenomenon typical of urban areas, in which there is a temperature increase compared to rural and peripheral areas of up to 5 degrees. Furthermore, hydrogeological instability and the almost total absence of biodiversity also contribute to urban pollution.

Urban greenery, then, is not “only” used to counteract CO2 emissions. As is now well known, plants are able to remove carbon dioxide from the atmosphere and store it in their bark and the soil, thus allowing them to counteract the effects of climate change. But not only that. Urban greenery is able to mitigate all the typical pollution phenomena of cities. It reduces temperatures in wooded areas, mitigates the presence of fine particulate matter in the air, significantly increases soil permeability, and contributes to a greater presence of wildlife and biodiversity. Its ability to lower temperatures also has positive secondary effects, because it allows for limiting the use of air conditioning inside homes, another highly polluting factor.

What is the situation today?

The Istat data regarding the presence of urban greenery in urban centers are not particularly reassuring. The percentage of greenery on municipal land is quite low: in almost 70% of provincial capitals, therefore the most densely populated, busy, and polluted areas, the average presence of urban greenery is less than 3% of the territory. According to the National Environmental Protection System, every citizen should have access near their home to a sufficient amount of green space, about 15 square meters per inhabitant. Figures that we are terribly far from.

Although investment in urban greenery has been repeatedly urged at the legislative level and through planning projects, most metropolitan areas fail to comply with the guidelines on a daily basis. Since 2013, the year in which the “Rules for the development of urban green spaces” were established, most of the projects started have been abandoned. It is the responsibility of local governments to implement those planning and territorial redevelopment projects necessary to make cities more livable centers that do not harm the health of citizens. But the recovery of most urban areas appears too difficult and, unfortunately, almost never a priority.