Scientists have been surprised by the number of trees that they have been able to detect in the Western Sahara, Sahel and Sudanian regions of Africa. Using satellite imagery, they were able to count more than 1.8-billion trees in a region generally regarded as being desert.
The study was focused on trees whose crowns were larger than 3 m2 in area. They were identified using high-resolution imagery provided by the Centre National de la Recherche Scientifique, France’s leading scientific research organisation. The imagery was analysed using artificial intelligence pattern recognition technology.
Although these trees are scattered, if they could be collected into a single forest it would cover an area of 1.3-million km2. This is equivalent to 2.5 times the size of France.
The density of these trees, and their crown size, is closely dependent on an area’s climate and the land use. These trees play a critical role in dry tropical ecosystems and agricultural systems. They are also crucial for biodiversity and carbon storage, as well as being important contributors to local resources.
The study has shown that it is possible to create an inventory of all the non-forest trees on Earth. The research was published in the journal Nature.