Deep sea mining test uncovered multiple new species
Researchers carrying out one of the largest impact studies into the potential environmental impacts of deep-sea mining have discovered a little more than they expected on the ocean floor: 4,350 animals, each measuring at least 0.3 millimeters. From these, they ultimately identified 788 distinct species of crustaceans, molluscs, marine bristle worms and other unique creatures living in this sought-after mining area.
Although the team found that harvesting rare earth metals from more than 13,000 feet below the ocean surface may not be a solution enough As destructive as initially theorized, these disruptions still cause serious concern. The team’s findings are published today in the journal Nature ecology and evolution.
Despite being one of the most inhospitable environments on the planet for humans, there is growing commercial interest in the deepest parts of the ocean. Unfortunately, this fascination is often less about conservation and more about profits. Indeed, some of the largest deposits of rare earth metals on the planet are found on the seabed, making them an increasingly attractive target for companies.
One of the most attractive targets for proponents of deep-sea mining is the Clarion-Clipperton Zone (CCZ), a continent-sized abyssal plain located at a depth of approximately 4 km between Hawaii and Mexico. In addition to being rich in minerals, the CCZ is also one of the least known habitats in the world. In 2022, marine biologists announced the discovery of more than 5,000 new cataloged species during a research excursion to the region.
With so much biodiversity remaining to be explored, conservationists have repeatedly expressed concerns about the environmental impacts of deep-sea mining in regions like the CCZ. However, there is virtually no research on the subject.
“Critical metals are necessary for our green transition and they are rare,” Thomas Dahlgren, a marine biologist at Sweden’s University of Gothenburg and co-author of the study, said in a statement. “Several of these metals are found in large quantities on the seabed, but until now no one has shown how they can be extracted or what impact this would have on the environment. »
To learn more about the possible effects, Dahlgren and his teammates surveyed a nearly 50-mile stretch of the CCZ two years before a deep-sea mineral extraction vehicle test was planned. They then returned two months after the collector for a total of 160 days of field work, having spotted more than 4,000 organisms living there, including 788 distinct species of molluscs, crustaceans, worms, marine silks, etc.
“I have worked in the Clarion-Clipperton area for over 13 years and this is by far the largest study ever conducted,” Dahlgren said. “As most species have not been previously described, molecular (DNA) data has been crucial in facilitating studies of seafloor biodiversity and ecology.”
The effects of the mining test were stark: following the machine’s trail, the team calculated a 37% decrease in the total animal population as well as a 32% decrease in diversity.
“Deep sea mining within the CCZ is at a critical juncture, as the industry seeks to move beyond the exploration phase and into commercial exploitation,” the study authors write. “Therefore, there is a clear need for direct assessment of the impacts of mining on seabed wildlife abundance and biodiversity. »
Once this first major project is completed, marine biologists hope it can serve as a basis for future analysis of the impacts of deep-sea mining. In the future, they also hope to investigate the 30 percent of the CCZ currently protected by environmental regulations.
“At present we have virtually no idea what lives there,” added Adrian Glover, a researcher at the Natural History Museum in London and co-author of the study.
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