But an ambitious project in Brazil's most crowded state, São Paulo, aims to bring the rainforest and its ecosystem back.
In an article published in Science magazine, Bernice Wuethrich reveals how the Riparian Forest Restoration Project aims to restore a million hectares of rainforest through experiments with different restoration methods in five pilot projects.
Some emphasize replanting trees alone while others aim to return a variety of plants and animals simultaneously. Their tactics include moving squares of topsoil from intact forest to deliver soil microbes, earthworms and fungi, and planting groundcover to attract butterflies.
Species diversity is seen as key to success, along with participation from locals. Farmers, for instance, volunteer land for replanting, while their children may work as environmental monitors.
The São Paulo government, looking to set up a fund for ecosystem services, says the project could become a model for all Brazil.