Just 3% of the world’s land remains ecologically intact with healthy populations of all its original animals and undisturbed habitat, a study suggests.
These fragments of wilderness undamaged by human activities are mainly in parts of the Amazon and Congo tropical forests, east Siberian and northern Canadian forests and tundra, and the Sahara. Invasive alien species including cats, foxes, rabbits, goats and camels have had a major impact on native species in Australia, with the study finding no intact areas left.
The researchers suggest reintroducing a small number of important species to some damaged areas, such as elephants or wolves – a move that could restore up to 20% of the world’s land to ecological intactness.
Previous analyses have identified wilderness areas based largely on satellite images and estimated that 20-40% of the Earth’s surface is little affected by humans. However, the scientists behind the new study argue that forests, savannah and tundra can appear intact from above but that, on the ground, vital species are missing. Elephants, for example, spread seeds and create important clearings in forests, while wolves can control populations of deer and elk. [Continue reading…]