Half of Amazonian trees at extinction risk

A new study has revealed that more than half of the 15,000 species of tree found in the Amazon rain forest are now on the brink of extinction.

Forests in the Amazon have been declining since the 1950s, but scientists still have a poor understanding of how this has affected populations of individual species.

The new study compared data from forest surveys across the Amazon with maps of current and projected deforestation to estimate how many tree species have been lost, and where.

The authors concluded that the Amazon could harbor more than 15,000 tree species, of which 36 to 57 percent likely qualify as being globally threatened under IUCN Red List of Threatened Species criteria.

"We aren't saying that the situation in the Amazon has suddenly gotten worse for tree species," said Pitman. "We're just offering a new estimate of how tree species have been affected by historical deforestation, and how they'll be affected by forest loss in the future."

Fortunately, the authors say, protected areas and indigenous territories now cover over half of the basin, and likely contain sizable populations of most threatened species.

The study is published in the journal Science Advances.