Fires and illegal logging of the equatorial rain forests of the Brazilian Amazon have led to the fact that the biome emits more carbon dioxide than it absorbs. This conclusion was reached by a group of scientists led by Luciana Vanni Gatti, an employee of the National Institute for Space Research (Inpe), the G1 portal reported on Wednesday.
"The first bad news is that fires and logging have turned the Amazon into a source of carbon emissions," the portal quotes her as saying. However, in addition to direct emissions, scientists point out, there are also indirect ones related to the consequences of the associated decrease in precipitation and the impact of this on the photosynthesis process.
"As we found out, the disappearance of forests led to a decrease in precipitation in these areas, primarily during the dry season (from August to October)," she continues. This, in turn, led to an average temperature increase of two degrees in the north-eastern part of the biome and two and a half degrees on its south-eastern border, where the so-called "deforestation arc" is located. As a result, this led to an increased level of carbon dioxide emissions compared to the norm. Scientists have estimated that forests emit 0.29 billion tons of carbon per year more than they absorb.
During the work, the scientists received and processed 590 air samples taken between 2010 and 2018 in four different points of the Amazon. Aircraft were used to fence them at various altitudes (from 300 m to 4,420 m above sea level). "We made this conclusion because, unlike other scientists who measure the amount of carbon in tree trunks, we measure the amount of carbon dioxide in the atmosphere itself. And its amount in the air is a direct consequence of what is happening in the Amazon right now," explains Gatti.
The results of the ecologists' research and the innovative calculation method used by them can be found in detail in the publication in the scientific journal Nature.
The Amazon rainforest is the largest tropical forest in the world, occupying a significant part of the territory of several countries of the South American continent. The area of the biome is 5.5 million square kilometers, of which almost 4.2 million square kilometers belong to Brazil. There are 2.5 thousand species of trees growing on the Brazilian territory, which is about a third of the entire tropical forest in the world, and 30 thousand plant species (out of 100 thousand species on the entire continent). The number of varieties of birds and mammals in the region is about 2 thousand.