New study: Half of all Amazon tree species are imperiled

Many Amazon tree species are naturally rare, making them vulnerable to future land-use changes

The Amazon harbors some of the biologically richest forests on the planet, and a new study suggests that over half of its myriad tree species are vulnerable to extinction.

Amazonian has suffered decades of intensive land uses that have destroyed a fifth of the region's forests and fragmented or degraded large additional expanses of forest.  If these threats continue unabated, then up to 57 percent of its roughly 15,000 tree species will be in danger, according to a research team that included ALERT's Bill Laurance.

Fortunately, most of the regions' tree species, although naturally very rare, are currently represented in Amazonia's existing protected areas and indigenous territories. 

If those reserves are well protected, then only a third of the Amazon's tree species are likely to be threatened, according to the study, which overlaid the known geographic range of each species on top of projected maps of future land-use change.

Notably, protected areas and indigenous territories now cover slightly over half of the Amazon basin.  But the region's reserves still face a barrage of legal and illegal threats, including dam construction, mining, wildfires, and droughts.

A stately acaricuara tree from central Amazonia (photo by William Laurance).

One key caveat is that the study did not take into account a number of emerging threats, such as the interaction of habitat disruption and climate change in the future.  If such threats turn out to be important, then the number of threatened species could be higher than predicted.

Brazil, which contains 60 percent of the Amazon forest, has sharply reduced its rate of deforestation in the last decade.  But forest loss continues rapidly elsewhere, and is accelerating in Bolivia and Peru. 

In total, an area of Amazon forest the size of about 4,500 soccer fields is still being lost every day.

Demand for beef, soy, and palm oil, which currently drives much Amazon deforestation, is likely to rise rapidly as the global population grows, increasing pressures to clear more forest.

Amazon deforestation for soy farming (photo from Greenpeace)

The fate of the Amazon is a battle we’ll see play out in our lifetimes.  Given the extreme rarity of many of its trees and other species, having large, well protected reserves is going to be crucial for ensuring most of Amazonia's unparalleled biodiversity survives indefinitely.