Over Half of Amazon Tree Species are at Risk of Extinction because of Deforestation

A new study has revealed that over 50% trees species in Amazon are at risk of extinction due deforestation. The journal Science Advances published the study which included more than 15,000 Amazon tree species, including Brazil nut and cacao producing plants.

Study researchers collected data in the forest and then compared it with maps of projected deforestation. They found that more than 36% tree species of Amazon could be listed threatened under the Red List of the International Union for Conservation of Nature.

The study also suggested that the count of threatened plant species around the world could be increased by more than 20%, while globally threatened tree species by more than one-third. Nigel Pitman, a tropical ecologist from the Field Museum in Chicago, said, "We've never had a good idea of how many Amazonian species were vulnerable. And now, with this study, we've got an estimate".

The ecologist is among over 150 researchers who are authors of the study. The researchers walked through the forest to measure diameters of the tree species. They also collected flower, leaves, fruits and branches while trekking into the Amazon. They collected data on more than 1,400 plots of forest.

The researchers used the collected data to create a computer model to examine it under two scenarios. In the first scenario, the researchers found that by mid-century, approximately 40% Amazon forests could vanish. The second scenario suggested more than 20% of the forest would disappear by 2050.

The findings were announced by a research team comprising 158 researchers from 21 countries, led by Hans ter Steege of Naturalis Biodiversity Center in the Netherlands and Nigel Pitman of The Field Museum in Chicago, USA. The Field Museum was heavily involved with this study—the paper was co-authored by The Field Museum's Corine Vriesendorp and relied on data contributed by the Field's Robin Foster. Furthermore, some of the tree plot data was collected through the Museum's rapid inventory program, in which ecologists, biologists, and anthropologists travel to the Amazon and take stock of the plants, animals, and people who live there.

The authors concluded that 36 to 57 percent of the Amazon's estimated 15,000 tree species likely qualify as globally threatened under IUCN Red List of Threatened Species criteria.

However, parks and reserves will only prevent extinction of threatened species, the paper emphasizes, if they suffer no further degradation. The authors caution that Amazonian forests and reserves still face a barrage of threats, from dam construction and mining to wildfires and droughts intensified by global warming, and direct invasions of indigenous lands.

William Laurance from James Cook University in Australia, who also contributed to the study, added: "Either we stand up and protect these critical parks and indigenous reserves, or deforestation will erode them until we see large-scale extinctions."

Those losses would likely affect iconic tree species including Brazil nut, cacao, and açai palm, which play central roles in the regional economy. What's more, Amazonian forests help trap a vast amount of carbon, which, if unleashed through deforestation, could exacerbate an already warming climate. "We want to make sure the Amazon keeps the carbon sink," ter Steege says. "This is important."

The Amazon basin hosts perhaps the greatest biodiversity on Earth—so much so that researchers know relatively little about many of the region's native species. "While we know quite a bit about Amazonian deforestation, we know little about the effects on the Amazonian [tree] species," says lead author Hans ter Steege, a senior research fellow at Naturalis Biodiversity Center in Leiden, the Netherlands.