Although the Amazon ecosystems are very diverse, the rainforest of the southeastern Amazon is no longer a terrestrial carbon sink. Deforestation, fires, and rapid local warming have reduced or eliminated its ability to release carbon dioxide. If the vast tropical forests that have absorbed them have reached saturation, this suggests worrying implications for future global warming.
Based on hundreds of samples collected at various altitudes over the past decade, a study published in shows that the particularly southeastern part of the Amazon went from source CO2,, responsible for global warming. Over the last fifty years, plants and soils have been absorbed by more than a quarter CO2, even when those emissions increased by 50%.
So, if Amazon – in which half lives particularly effective in absorbing this carbon and storing 450 billion tons of CO2 in his and its soils -, became a constant source of C02, resolving the climate crisis would become even more difficult.
And always the same litany: deforestation, arson, intensive agriculture
Among the causes of this , forests to make room for breeding and. Climate change is also a key factor: temperatures during drying operations increased by almost 3 ° C compared to pre-industrial times, almost three times higher than the world average. A combination of all these factors ” calls into question the ability of tropical forests to separate large ones CO2 derived from ”, Notes Scott Denning of the University of Colorado, in a comment also posted in Nature.
Deforestation and forest degradation reduce the Amazon’s ability to act as a carbon sink
This question has long worried scientists, but so far they have not provided a complete answer, especially because above the region. To circumvent the problem, a Brazilian research team collected 600 CO samples2 and from between 2010 and 2018 at altitudes up to 4.5 km above the ground. According to their findings, the northwestern part of the Amazon is in equilibrium, absorbing so much CO2 which broadcasts in. But the east, especially in the dry season, is becoming a net source.
Another recent study, using a different methodology, concluded that Brazilian Amazon released almost 20% CO between 2010 and 2019.2 more than it broadcast. With from , thawing or the disappearance of coral reefs, the fall of the Amazon rainforest are among identified by scientists as key elements whose significant modification could lead the climate system to dramatic and inevitable change.
Brazil: The Amazon rainforest now emits more CO2 than it absorbed in 10 years!
ETX Study article, published May 4, 2021
The remark is here: over the last decade, the Amazon rainforest has been shedding more carbon than it is absorbing, causing global warming and human activities. But also, in terms of deforestation, which increased sharply in 2019, degradation of forested areas along the edges is another important parameter as well as deforestation, which greatly contributes to the weakening of the Brazilian Amazon rainforest.
The The Brazilian, a victim of climate change and human activities, has released more carbon over the past ten years than it has absorbed, a big and unprecedented change, according to a study released this week. No noise, one of ” “From a planet that absorbs between 25 and 30% of the greenhouse gases emitted by humans, climate change would be much worse. But for several years now, scientists have been worried about shortness of breath , and they are afraid that they will play their role less and less well. . And the concern comes especially from the Amazon rainforest, which accounts for half of the planet’s tropical forests.
The study was published Thursday in international team, looks at the Brazilian Amazon, which represents 60% of this primary forest, and the situation is bleak. Between 2010 and 2019, this forest lost biomass: carbon losses in the Brazilian Amazon are approximately 18% higher than gains, according to (Inrae).
The Amazon rainforest, our last rampart, could overturn
” This is the first time we have figures showing that we have switched and that the Brazilian Amazon is broadcasting “The carbon network,” one of the authors, Jean-Pierre Wigneron, a researcher at INRAE, told AFP. a priori, ” other countries make up for the losses of the Brazilian Amazon ” and so “ the whole Amazon hasn’t switched yet, but it could do so soon He continues.
” So far, forests, especially tropical forests, have protected us by helping combat global warming, but our last bulwark, the Amazon, is in the process of being overturned. », Warns the researcher. The study also highlights an unrecognized but major responsibility for forest “degradation”. Unlike causing the wooded area to disappear, the degradation ends everything that can damage it without completely destroying it: weakened trees on the edge of forested areas, selective felling, small fires, obtaining trees associated with drought. Less affected easily noticeable than flattened large areas.
Using the index of emitted vegetation microwave, allowing probing the whole vegetation, not just the top , the study of these forest degradations recorded 73% carbon losses, compared to 27% due to deforestation, however large.