Brazilian photographer Sebastião Salgado and his wife Lélia have planted 2 million trees in 20 years to restore a destroyed forest in Brazil, stimulating a revival in bio-diversity of insects, birds and fish.

In the 1990s, only about 0.5% of the land was covered in trees. Sebastião and Lélia founded Instituto Terra, a small organisation that has since planted 4 million saplings and has brought the forest back to life. “Perhaps we have a solution.” Sebastião said. “There is a single being which can transform CO2 into oxygen, which is the tree. We need to start tree planting on a massive scale. You need a forest with native trees, and you need to gather the seeds in the same region you plant them, or the serpents, and the termites won’t come. And if you plant forests that don’t belong there, the animal population won’t grow, and the forest will be silent.”