De plus en plus de végétation et d'arbres sur la planète, mais une baisse de biodiviersité

The research suggests an area covering 2.24 million square kilometers (...) has been added to global tree cover since 1982. This equates to 7% of the Earth’s surface covered by new trees.

The findings may appear to contradict the long-established view that forests are being destroyed. A report from the UN’s Food and Agriculture Organization, for example, says there has been a net loss of 1.29 million square kilometers of forest between 1990 and 2015.

Large tree losses in Brazil were balanced by canopy gains in Europe, Asia and North America. Russia, for example, added 790,000 square kilometers, while China added 324,000 square kilometers.


Agricultural abandonment in Europe, Asia and North America, together with tree planting programmes in places like China have also driven canopy growth.

And rising temperatures have enabled forested areas to flourish closer to the poles causing canopy cover to expand. Grasses, shrubs and trees can now thrive even in deserts, mountain regions and tundra.

However, an important distinction needs to be made between tree cover and forest cover.

The study points out that industrial timber plantations, mature oil palm estates and other specifically planted forests add to global tree cover. On paper these areas compensate for the primary forest that has been cut down; 100-hectare loss of primary forest is perfectly offset by a 100-hectare gain on a man-made plantation, for example.
But while they may be equal in area, they are not equal in biodiversity.

The research attributes 60% of all land-use change throughout the study period directly to human activity, with the remaining 40% caused by indirect factors like climate change.