The massive accumulation of biomass, fueled by fertilizers and waste from the Amazon, consolidates an unprecedented oceanic phenomenon on the American and African coasts, forming the Great Atlantic Sargassum Belt.
What began as sporadic sightings has now consolidated into a global-scale environmental crisis: the Great Atlantic Sargassum Belt.
Recent research confirms that this macroalgae ecosystem has reached record dimensions, extending from the coasts of West Africa to the Gulf of Mexico, driven by a critical combination of anthropogenic factors and changes in ocean dynamics.
Unlike the natural blooms of the past, the current proliferation of this “brown tide” has a direct relationship with the increase of nutrients in the ocean.
Experts point out that the massive discharge of nitrogen and phosphate fertilizers from intensive agriculture, along with the release of untreated wastewater through the Amazon River, acts as a potent fuel for the accelerated growth of these algae.
A phenomenon marked by deforestation and runoff
The origin of this problem is traced inland. The increasing deforestation in the Amazon basin has reduced the soil’s retention capacity, allowing rain to carry larger amounts of sediments and agricultural chemicals into the sea.
This flow of nutrients, when meeting the warm waters of the tropical Atlantic, creates the ideal conditions for the Great Atlantic Sargassum Belt to expand uncontrollably.
Since 2011, the frequency and density of these accumulations have marked a turning point. What was once a predictable seasonal cycle has transformed into a recurring event that severely impacts marine biodiversity, obstructing coral reefs and altering the nesting habitats of sea turtles.
Socioeconomic impact in the region of the Great Atlantic Sargassum Belt
Beyond the ecological disaster, the massive presence of sargassum poses a direct threat to local economies, especially in the Caribbean.
The decomposition of these algae on the beaches not only releases toxic gases and foul odors but also drives away tourism and complicates artisanal fishing activities.
The international scientific community agrees that, unless nutrient discharges are managed efficiently and the degradation of river basins is halted, the Great Atlantic Sargassum Belt will continue to be a persistent phenomenon that will force affected countries to develop new large-scale mitigation and cleanup strategies.
