The article "Spiral Border Threats in the Amazon Indigenous Territory", published on July 28, 2026, in the journal Nature Sustainability, had one of its authors as the postdoctoral student of the Postgraduate Program in Physics at the Federal University of Santa Maria (UFSM), Alecsander Mergen.
The researcher was responsible for processing satellite images of areas around the Javari Valley Indigenous Territory, located in the western region of the state of Amazonas. Deforestation indices were identified at distances of 5, 10, 50, 100 and 200 kilometers from the mapped territory.
The work took place during Alecsander's doctoral sandwich at theUniversity of South Alabamabetween June 1st and December 31st, 2025. The collaboration originated from an invitation by Professor Gabriel de Oliveira, who is employed at the institution in the United States and leads the research.
The data collection via satellite was carried out and analyzed by Alexander during his doctoral studies at UFSM. In his thesis, he identified the exchanges of carbon dioxide (CO₂) in areas of cattle farming with native vegetation in the Pampas, using satellite images, in order to develop models capable of monitoring them throughout the biome.
During his doctoral internship, the scientist was able to expand his knowledge of remote sensing in the Javari area, in the Amazon. To create specific models for the analysis of the Brazilian territory, studies were also carried out in the Mobile-Tensaw River Delta, in Mobile, Alabama. Alexander believes that this region is similar to the Javari Valley, as it is bordered by a large river and surrounded by vegetation.
The Javari Valley is the area with the highest concentration of voluntarily isolated Indigenous peoples in the world. With 8,544,440 hectares, the valley is located between the borders of Brazil, Peru and Colombia.The territory gained worldwide attention in 2022 after the murders of American journalist Dom Phillips and Brazilian indigenous researcher Bruno Pereira, which exposed the threats of illegal activities in the region.
Deforestation, violence, and illegal resource extraction
The buffer zone around the Vale do Javari, a 200-kilometer area surrounding the indigenous territory and considered a protected area,was analyzed via satellite to identify the deforestation situation in the region. The study results showed that the further away from the Indigenous Territory, the higher the deforestation rates. "This shows how important it is to preserve these indigenous areas and the preservation power they have in the Amazon region," noted researcher Alexander Mergen from the PPG in Physics.
The study also shows that since 2008, environmental destruction has been increasing in the Vale do Javari. Between 2017 and 2022, deforestation increased exponentially. In 2022, the forest loss around the territory was 187.5 times greater than within the Indigenous Territory itself. There are several causes for this result. The researcher points to agricultural activity in the Amazon as one of the responsible factors.
Furthermore, drug trafficking, illegal hunting, and fishing are the main causes of invasions and direct threats to the Indigenous Land. Vulnerability occurs due to the territory's border location. Alexander suggests that, especially in the most remote areas, public policies of monitoring should be increased.
In the Javari Valley, five indigenous peoples maintain contact with the surrounding society: the Marubo, Mayoruna, Matis, Kanamari, and Kulina. Two groups have recent contact: the Korubo and Tsohóm-Djapá. And at least 14 groups live in voluntary isolation.
High-quality science
Before returning to Brazil, the scientist participated in the 2025 Annual Meeting of theAmerican Geophysical Union(AGU) in New Orleans, Louisiana. The meeting is considered the largest in the world in the field of biogeosciences. "UFSM has thisknow-howvery large in being able to make contacts and having this scientific power. Everyone knows the University of Santa Maria, so this opens a lot of doors," said.
In addition to studying border threats in the Amazon from satellite data, Alexander's work atUniversity of South Alabamaresulted in the installation of flux towers to monitor gas emissions resulting from the greenhouse effect. Following the experiment, there was an opportunity for a partnership with theInstituto Mamirauáto implement a flux tower in an environmental protection area in the Amazon.
The research leader, Professor Gabriel de Oliveira, also invited him to pursue a postdoctoral fellowship in the United States. However, he had already received an invitation from the Laboratory of Greenhouse Gases (LABGEE), Alexander decided to stay at UFSM. The researcher assesses the relevance of the experience abroad for the pursuit of knowledge, but observes the importance of contributing to the evolution of Brazilian research and showing the world the high-quality science produced in the country.
The professor at the Physics Postgraduate Program at UFSM, Débora Roberti, emphasizes that when students return to UFSM, they bring knowledge to research groups and contribute to the training of other colleagues. "The benefit of students going abroad does not only apply to them. They also bring this scientific and institutional return to the University," she assesses. The professor also recalls that the Postgraduate Program participates in Capes Global, an initiative that fosters international cooperation networks between Brazilian higher education institutions with different levels of internationalization.
The article "Threats Spiraling in the Amazon Indigenous Territory" can be accessed in the journalNature Sustainability.
Text: Nicolle Seixas, a journalism student and volunteer at the news agency.
Photo: Personal collection / Gabriel de Oliveira / Erin Koster
Chart:Alexander Mergen / Gabriel de Oliveira / Erin Koster
Edition: Mauricio Dias, journalist