Despite the resumption of public environmental policies that have effectively slashed deforestation in the Amazon, degradation is on the rise as warnings have been issued for close to 163 thousand km² of the biome.
The figure is three times higher than the almost 58.5 km² reached by deforestation alerts registered by Brazil's National Institute for Space Research (INPE) up to March this year.
From March 2023 to the same month this year, warnings of degradation were recorded for a further 20,400 km², and contrary to the reduction in deforestation warnings for this time span, the numbers increased when compared to the warnings for the 18 thousand km² in the same period last year.
According to André Lima, extraordinary secretary for Deforestation Control and Environmental Planning at the Environment Ministry, forest degradation is a problem that has already been under the government's radar. “The fight against illegal activities gives us the feeling there is no more impunity, and this discourages degradation, especially in the form of selective logging,” he noted.
According to David Lapola, a researcher at the University of Campinas (Unicamp), forest degradation is more complex than deforestation and represents a serious threat to Brazil's efforts to meet the targets set out in international agreements to preserve climate stability. Camouflaged by fragile vegetation, man-made environmental disturbances are encroaching on biodiversity, far from the reach of satellite images and government monitoring.
Distinct phenomena
The expert pointed out that deforestation and degradation are different phenomena resulting from disturbances caused by human action—such as fire, edge effects (the impact on forests bordering degraded areas), and selective logging—and by drought—which stems from natural factors as well as from human-caused climate change.
Lapola, who coordinated the study The Drivers and Impacts of Amazon Forest Degradation , published in the journal Science in 2023, pointed out that, unlike deforestation—which eliminates the forest and makes way for other landscapes such as pasture—degradation affects the forest's ecosystem mechanisms in a more subtle way and over a longer period of time. In practice, it transforms the forest from within by replacing species of both flora and fauna. Larger trees give way to trees with smaller structures, less biomass, and less capacity to perform ecosystem roles.
In the publication, Lapola examines data from 2001 to 2018 and notes that degradation is advancing faster and has affected the Amazon more than deforestation. “The problem is that the effects of degradation are the same as those of deforestation. In some studies, some authors point to even greater damage,” he remarked. Consequences include a lower capacity to retain CO2, interference in the water cycle, with less rainfall, and temperature hikes.
Monitoring
In addition to the diagnosis, the research stresses the need to step up monitoring methods. As it stands today, the Brazilian government bases its public policies mainly on data generated by two tools: the Project for Monitoring Deforestation in the Legal Amazon by Satellite (Prodes), which gathers annual information on what has been deforested, and the Real-Time Deforestation Detection System (Deter), with daily alerts but less precision.
With the aid of satellite images, Deter can generate degradation alerts by detecting events chiefly linked to fire and illegal logging. “These two main events change the canopy. By looking at the satellite, you see that the treetops have a different spectral signature from the undisturbed forest, even though the area is not converted into an area of exposed soil,” said Luiz Aragão, an INPE researcher specializing in tropical ecosystems with a focus on remote sensing.
In Lapola's opinion, even though this support is effective in tackling deforestation, it fails to encompass all the factors that cause degradation, which may indicate that the current estimates are underrated.
“It's quite possible that last year saw a sharp surge in degradation, mostly due to the drought, because El Niño was relatively severe and there was a drastic reduction in river levels, especially in the Central Amazon. As a result, we can assume that the drought has also led to degradation, but we don't have any figures yet, and the right thing to do is to have a system for monitoring this nonstop.”
The researcher added that disturbances such as fire and selective logging are more observable through satellite images, but the edge effect—which also generates degradation in areas close to forests—is more complex and requires other forms of monitoring.
“We can look at the calculations and understand that a certain area is an edge, but we have to calculate how old that edge is, because the older it gets, the more carbon it loses. The trees die slowly; it's not an instantaneous process,” he argued.
Public policies
André Lima says that the ministry recognizes the need to improve degradation monitoring methods and that the issue has been the subject of much debate.
“A more precise system could be used to calculate annual rates. This is being discussed with INPE, with the possibility of a new project for the Amazon Fund to boost the development of methods and the system for gauging degradation.”
According to Aragão, these limitations were taken into account in the latest update of the Action Plan for the Prevention and Control of Deforestation in the Amazon, launched in June 2023. However, further action must be taken.
“We need to develop new policies and initiatives aimed directly at forest degradation, in addition to those we already have in place to tackle deforestation,” he argued.
According to André Lima, this work has made strides, but the interruption of environmental policies in the recent past has resulted in a setback that should be addressed first and foremost: “Before 2023, we had four years of enforcement with really low quality and intensity. This has brought about a strong perception of impunity and degradation, especially in the form of irregular logging.”
The secretary pointed out that environmental degradation is within the scope of programs against deforestation, such as the ones conducted by priority municipalities under the Federal Program with Municipalities for Reducing Deforestation and Forest Fires, which earmarks resources from the Amazon Fund for local control and monitoring efforts, land and environmental regulation, recovery of native vegetation, and support for sustainable production.
“Several municipalities made the list this year, but not because of deforestation. They were included because of degradation. They should become the focus of more intense monitoring and key incentives,” he declared.
Aragão believes that progress needs to be based on a realistic vision of the problems. As an example, he cited the use of fire, which must be replaced with other forms of management made possible by new technologies. On the other hand, fire use in traditional forms of subsistence cannot be ignored either.
“We need an alternate policy where education points to the most appropriate way and the right time to resort to fire with minimal impact, protecting the forest.”
Faced with these challenges, all the researchers agree it is necessary to join forces to tackle the disturbances that affect forests and lead to a degenerative process.
“Deforestation and forest degradation must be stopped so we can use natural resources to their full potential, providing bioeconomic solutions and maintaining climate stability and well-being for local communities as well as the region's own socioeconomic development,” Aragão concluded.