Ravaged by human disturbances, deforestation, drought and fires, over a third of the Amazon rainforest has been rapidly deteriorating, according to two new studies which have raised concerns that the rainforest with a unique ecosystem may be approaching a point of no return.
The two new researches studies published in the journal Science in January 2023 revealed that the Amazon is swiftly transforming – and it may be at risk of collapsing into a new kind of ecosystem altogether.
Human disturbances have degraded more than a third of the Amazon rainforest, the first study found. Fires; selective logging; habitat fragmentation; and drought, which is worsened by climate change, are all chipping away at one of the world’s most iconic ecosystems.
The study focuses only on degradation, activities that damage the forest but don’t remove all the trees from the landscape. It doesn’t include deforestation, which clears a forest area. That’s another problem entirely, with recent estimates suggesting that as much as 17% of the Amazon has already been cleared.
The researchers said degradation tends to get less attention than deforestation but it’s still a serious threat. Even though trees remain standing, degraded forests are often less resilient to future disturbances. This puts them at greater risk of dying and transforming into different kinds of ecosystems, like grasslands. Degraded forests also tend to store less carbon.
The researchers used satellite data to estimate the extent of forest area affected by four major disturbances: droughts; fires; timber extraction, when trees are selectively logged from inside the forest without clearing the entire landscape; and “edge effects,” which is when the edges of a forest become more vulnerable to disturbances.
The Amazon is among the most biodiverse ecosystems on Earth and is estimated to contain at least 10% of all the world’s plant and vertebrate animal species in one place.
Amazon also contains vast stores of carbon, locked up in its trees and soil. It is estimated that the entire Amazon ecosystem may contain as much as 180bn tons of carbon – that’s about a quarter of all the carbon that’s entered the atmosphere since the industrial revolution began. M