Today, we do not know exactly how many animal and plant species live with us on Earth. Twenty years ago, the work of scientist Robert May estimated that we would succeed in making an inventory of all terrestrial species in 2044 only.
But we are in 2022, and scientists have already completed the plant inventory. According to their work, 64,000 different tree species have already been identified on our planet, but in reality there are 14% more and there would therefore remain some 9,000 species of trees to be discovered. Their work has been published in the journal of the US National Academy of Sciences.
It therefore remains to discover them, which may seem difficult insofar as we do not know them precisely. But this figure is not intuition, it is mathematics. To obtain this result, the authors parsed the two main databases on the composition of forests in 90 countries. In the different samples of forests studied, some specimens of trees are very rare, there are only a few dozen, it took a lot of luck to come across them.
This suggests that there are surely others who have not yet been identified. With rules of statistics and probabilities, these researchers have therefore developed a mathematical equation which makes it possible to estimate the number of tree species that have not yet been discovered by geographical area.
These new, still unknown tree species are mainly found in tropical and humid areas, particularly in South America. Discovering these trees, even if they are rare, is important for the conservation of forests throughout the world because the more the forests are diversified in species, the more they resist, in particular to climate change.
This study therefore shows once again the crucial place of tropical forests in the balance of the planet. However, over the past 40 years, forest areas have increased in temperate zones to the detriment of tropical zones. Latest example: in Brazil in January, nearly 430 km² of Amazonian forest were destroyed. This is five times more than in January 2021.