Microbes’ risk from deep-sea mining greatly varies

Hydrothermal vents on the seafloor support a rich diversity of life, and they contain deposits of valuable metals used in the manufacture of lithium-ion batteries. A new research paper looks at what is known about the vital microscopic life in these locations to evaluate the possible impacts of mining these and other deep-sea locations. Credit: Woods Hole Oceanographic Institution

A new paper, published in Limnology and Oceanography, shows that microbes in deep-sea ecosystems may suffer from varying risks  due to mining the sea floor.

Four types of deep-sea mineral resources have been analysed in the study, which include metal-rich rocks that are found around underwater mountains or lying on the seafloor. The findings of the paper, titled, Impacts of deep-sea mining on microbial ecosystem services, indicate that the probable impacts of mining vary significantly from creating a minimal disturbance to irreversible loss of significant ecosystem processes.

Beth Orcutt, senior research scientist at Bigelow Laboratory for Ocean Sciences, USA, a non-profit research institute, and the lead author of the study said, “The push for deep-sea mining has really accelerated in the last few years, and it is crucial that policy makers and the industry understand these microbes and the services they provide.”

Though guidelines already exist for licensed exploration, and the site assessments carried out should include how much microbial life is present, the new study emphasises that determining what roles the microbes in those ecosystems are playing and how they would be impacted by mining is equally important.

James Bradley, co-author of the paper and scientist at Queen Mary University of London, UK, explained, “It is important to understand the potential impacts of mining activities to figure out if they should occur and how to manage them if they do. This is an important conversation between policy makers, industry, and the scientific community, and it’s important that we work together to get this right. Once these ecosystems are damaged, they may never fully recover.”

Microbes on the seafloor play an essential role in the marine ecosystem, from fueling the food chain to powering global nutrient cycles. It is these environments that are also proving promising for deep-sea mining projects to be carried out.

The demand for deep-sea mining is driven by consumer demand for goods such as smartphones and electric cars, and the need for metals like cobalt and other rare earth elements, which are used in lithium batteries. The International Seabed Authority of the United Nations is working to establish guidelines for countries and contractors to explore the seafloor for minerals, and to eventually mine them.