In recent years, tree planting has become the cornerstone of many environmental campaigns, seen as an effective but simple way to help reduce the impact of carbon emissions, and also restore natural ecosystems.
For example, in January 2020 the World Economic Forum in Davos launched the 1 billion trees campaign , with the aim of supporting the United Nations Decade for the Restoration of Ecosystems, which aims to restore, protect and / or plant one billion trees by 2030 . An initiative, moreover, that followed a similar campaign to plant one billion trees by 2050.
But why are trees so useful in the fight against global warming and pollution? There is no doubt that trees are true carbon storage machines . In fact, like all plants, they absorb carbon dioxide in the atmosphere through a process called photosynthesis. Thus, they produce oxygen, which we breathe, and which is a by-product of this process.
Forests have the ability to sequester carbon for centuries , something that both humans and the planet urgently need as a result of the damage caused to the atmosphere by different carbon-emitting activities.
According to an estimate carried out by the UK conservation charity, the Woodland Trust, 400 tonnes of carbon can be trapped in 10,000 square meters of forest (that is, the equivalent of two and a half football fields).
Now, researchers at Rice University in the United States have wondered where and which trees would be better to plant as an effective way to limit the effects of global warming. They concluded that, for the city of Houston, for example, sycamores and American oaks could be considered the best options of the 17 super trees that can be useful in helping to make the environment more livable. .
In that study, the researchers set out to identify which trees would “work” best in the city, taking one important consideration: their ability to absorb carbon dioxide and other pollutants, and their ability to provide a canopy to reduce heat or stabilize the landscape during floods.
Taking all these factors into account, the experts ruled out most of the 54 native species, selecting only 17. Among them, it seems, the enzyme became one of the most effective in absorbing all types of contamination . Although the American sycamore came to stand out as one of the most interesting options when it comes to creating shady areas and containing floods.
On the other hand, bay leaves and red maple leaves would be best suited for removing ozone pollution, sulfur dioxide, nitrogen oxides, carbon monoxide, and even finer particles. All of these compounds can have serious health effects, such as asthma attacks or, in more serious cases, even cardiac arrest.
Once these maps were established, the study authors joined forces with the city and with various local partners in order to plant more than 15,000 super trees in 14 sites, mainly in those areas most affected by pollution, or in those most in need of maintenance. carbon storage or flood control.
Thanks to the results obtained, the researchers propose a three-axis strategy that could be transferred to other cities : determine which trees are the most suitable, identify the places where such plantation would have a greater impact on health and the environment, and engage with the community to make the plantation project a reality.