New study reveals alarming degree of human impact

Photo of a burning forest in Belterra, Brazilian Amazon, taken in 2015. In this photo, the height of the flame is about 30 cm. In the background of the photo, a solid line of fire is visible along with a lot of smoke. Credit: Adam Ronan/Rede Amazonia Sustentavel.

A new study recently published in the journal Science shows that the Amazon rainforest has suffered far more damage than previously thought, with more than a third of the remaining forests affected by human activities.

A study by a team of 35 international scientists from institutions such as the University of Campinas in Brazil, the Amazon Ecological Research Institute, the National Space Research Institute and Lancaster University in the UK shows that up to 38% of the Amazon’s remaining forests – the equivalent of ten times the size of the UK – suffered from human disturbance. This results in carbon emissions comparable to or greater than those from deforestation.

Photo of a burning forest in Belterra, Brazilian Amazon, taken in 2015. Although the flames are not visible, the smoke coming out of the forest is clear. Credit: Adam Ronan/Rede Amazonia Sustentavel.

The work is the result of the AIMES (Analysis, Integration and Modeling of the Earth System) project, associated with the international initiative Future Earth, which brings together scientists and researchers studying sustainability.

The findings are the result of an analytical review of previously published scientific data based on satellite imagery and a synthesis of published data describing changes in the Amazon region between 2001 and 2018. The authors define the concept of degradation as temporary or long-term changes. in forest conditions due to human fault.

The photo was taken in 2019, four years after the fire affected this piece of forest, which had previously also been subject to numerous human impacts, including selective logging, edge effects and fires. The photo was taken in Belterra, in the Brazilian Amazon. Credit: Marysilda Krupp/Rede Amazonia Sustentavel.

Degradation is different from deforestation, where a forest is completely removed and a new land use, such as agriculture, is established in its place. Although highly degraded forests may lose almost all trees, the land use itself does not change.

The authors assess four main drivers of forest degradation: wildfires, edge effects (changes occurring in forests adjacent to deforested areas), selective logging (eg illegal logging), and severe drought. Various forest areas may be affected by one or more of these disturbances.

The photo was taken in 2019, four years after the fire affected this piece of forest, which had previously also been subject to numerous human impacts, including selective logging, edge effects and fires. The photo was taken in Belterra, in the Brazilian Amazon. Credit: Marysilda Krupp/Rede Amazonia Sustentavel.

“Despite the uncertainty about the overall impact of these disturbances, it is clear that their cumulative effect could be as important as deforestation to carbon emissions and biodiversity loss,” said Jos Barlow, professor of environmental sciences at Lancaster University in the UK and co-author. the author of the article.

Scientists believe that the degradation of the Amazon also has significant socio-economic consequences, which should be further studied in the future.

Expanded final figure of the article. Credit: Alex Argozino/Studio Argozino/Science magazine.

“Degradation benefits a few but weighs heavily on many,” says Dr Rachel Carmenta, co-author at the University of East Anglia in the UK. “Few people benefit from degradation processes, but many lose out in all aspects of human well-being, including health, nutrition and attachment to the forest landscapes in which they live. Moreover, many of these hardships are currently hidden; recognizing them will help improve governance with social justice at the center.”

Photo of a burning forest in Belterra, Brazilian Amazon, taken in 2015. In this photo, the line of fire is clear, as is the smoke of a burning forest. Credit: Adam Ronan/Rede Amazonia Sustentavel.

In the team’s projection for 2050, the four degradation drivers will continue to be the main sources of carbon emissions into the atmosphere, regardless of increasing or suppressing forest deforestation.

“Even in an optimistic scenario where there is no more deforestation, the effects of climate change will indicate that forest degradation will continue, leading to further carbon emissions,” says Dr. David Lapola, study leader and Research Fellow at the Center for Research. Application of weather and climate research in agriculture at Unicamp. However, “preventing further deforestation remains vital, and it may also allow more attention to be paid to other drivers of forest degradation.”

The photo was taken in 2018, three years after the fire affected this cut forest, which was also affected by edge effects. The photo was taken in Belterra, in the Brazilian Amazon. Credit: Erica Berenguer

The authors propose to create a system for monitoring forest degradation, as well as the prevention and suppression of illegal logging and control over the use of fire. One of the proposals is the concept of “smart forests”, which, like the idea of ​​”smart cities”, will use various types of technologies and sensors to collect useful data in order to improve the quality of the environment.

“Public and private actions and policies that aim to curb deforestation are not necessarily also aimed at combating degradation,” says Dr. Lapola. “We need to invest in innovative strategies.”

Reference: Drivers and Consequences of Amazon Forest Degradation by David M. Lapola, Patricia Piño, Jos Barlow, Louis E.O.K. Aragao, Erika Berenguer, Rachel Carmenta, Hanna M. Liddy, Hugo Seixas, Camila V. J. Silva, Celso J. L. Silva-Junior, Ane A.S. Alencar, Liana O. Anderson, Dolors Armenteras, Victor Brovkin, Kim Calders, Jeffrey Chambers, Luisa Cini, Marcos J. Costa, Bruno L. Faria, Philip M. Fernside, Joyce Ferreira, Luciana Gatti, Victor Hugo Gutierrez – Vélez, Zhangang Khan, Kathleen Hibbard, Charles Coven, Peter Lawrence, Julia Pongratz, Bruno T.T. Portela, Mark Rouncewell, Alex S. Ruan, Rüdiger Schaldach, Sonaira S. da Silva, Celso von Randow, and Wayne S. Walker, January 27. 2023, Science.