WASHINGTON — More than a third of the Amazon rainforest may have been degraded by human activity and drought, researchers said Thursday, requiring action to protect the critical ecosystem. am.
In a study published in the journal Science, researchers say the damage to forests across nine countries is far greater than previously known.
For this study, they examined the effects of fire, logging, drought, and habitat change along forest boundaries. This is what is called the edge effect.
Most previous research on the Amazon ecosystem has focused on the consequences of deforestation.
The study found that between 2001 and 2018, fires, logging and edge effects degraded at least 5.5% of the Amazon’s remaining forest, or 364,748 square kilometers.
However, when the effects of drought are taken into account, the degraded area increases to 2.5 million square kilometers, or 38% of the Amazon’s remaining forest.
“As land-use change and anthropogenic climate change progress, extreme droughts are becoming increasingly frequent in the Amazon, impacting tree mortality, fire rates and carbon emissions to the atmosphere.” said the researchers.
“Forest fires intensify in years of drought,” they said, warning of the danger of “much larger megafires” in the future.
Researchers from Brazil’s Universidade Estadual de Campinas and other institutions used satellite imagery and other data from 2001 to 2018 to reach their conclusions.
In another study of human impacts on the Amazon, published in the journal Science, researchers at the University of Louisiana, Lafayette, and others issued a call to action.
“The Amazon is rapidly shifting from a largely natural to a devastated and altered landscape under the combined pressure of regional deforestation and global climate change,” they said. .
“Changes are occurring too quickly for Amazonian species, people and ecosystems to respond adaptively,” they said. “The policies to prevent the worst consequences are known and must be enacted immediately.
“To fail the Amazon is to fail the biosphere, and we are failing to take risks,” they said.
Brazil’s new president, leftist Luis Inacio Lula da Silva, has pledged to end deforestation in the Amazon by 2030.