Brazil's Atlantic forest, the country's most beleaguered biome and home to 80% of the population - including the likes of Rio de Janeiro and São Paulo - has posted its lowest deforestation numbers since record-keeping began 40 years ago. In 2025, the forest lost 8,658 hectares, the first time the annual toll has dipped below 10,000 hectares since 1985. Environmentalists are cautiously celebrating, suggesting this could pave the way for "zero deforestation" within a few years, though they're quick to point out the potential pitfalls that could send the trend into reverse.
One such pitfall is the so-called "devastation bill" recently approved by Brazil's congress, which dramatically weakens environmental law. The other is the possibility of a far-right government returning to power in the October presidential election, with Flávio Bolsonaro - senator and son of former president Jair Bolsonaro - neck-and-neck in the polls with current president Luiz Inácio Lula da Silva. "It's a very worrying scenario," said Luís Fernando Guedes Pinto, executive director of the NGO SOS Mata Atlântica, warning that a Bolsonaro victory could mean Brazil squandering its chance to be a global environmental leader. During the elder Bolsonaro's 2019 - 23 administration, deforestation surged and a gold rush invaded Indigenous lands - a fate many fear could repeat if his son, who has vowed to follow the same playbook, takes power.
The new data, released Thursday, comes from two monitoring systems run by SOS Mata Atlântica and partners. One, spanning four decades, showed a 40% drop in deforestation from 2024 to 2025, from 14,366 to 8,658 hectares - a stark contrast to the over 20,000 hectares lost annually during Bolsonaro's final two years. The other, a newer system tracking since 2022, recorded a 28% decline from 53,303 to 38,385 hectares, the lowest in its short history. The difference, the NGO explains, stems from the satellites used: the newer one is more precise, the older one offers a longer historical view.
Despite the progress, Pinto notes that "deforestation is still high" in the biome, emphasizing that "in the Atlantic forest, every fragment lost makes a huge difference." The biome is Brazil's third largest, after the Amazon and Cerrado savanna, but it's by far the most urbanized and degraded - only 24% of its original forest cover remains, compared to the Amazon's 80% and the Cerrado's 50%. Still, if the current downward trend holds - driven by public pressure, civil society mobilization, environmental policies, and enforcement - Pinto believes the forest could reach "zero deforestation" within three years.
Standing in the way is the new law, widely considered the biggest blow to Brazil's environmental legislation since licensing became a legal requirement in the 1980s. Lula vetoed parts of it, but a largely conservative congress overturned those vetoes at the end of 2025. The law removes the requirement for federal environmental agency approval before states can authorize deforestation, leaving decisions entirely to local authorities - a move now being challenged in the supreme court. Malu Ribeiro, director of public policy at SOS Mata Atlântica, called the law a "distortion" that puts Brazil at odds with the Paris agreement and could worsen climate disasters. "Weakening protection instruments now risks everything we have spent years building," she added.