Researchers from the University of Exeter, UK, claim that deep-sea mining in international waters (which could start in as little as two years) could cause irreversible damage to aquatic ecosystems and affect many different marine species, according to a study published in the journal Frontiers in Marine Science (1).
The deep-sea – areas below 200m – covers over half of our planet’s surface. Despite the wide range of species living in these waters, we know very little about these ecosystems. For example, we don’t understand how the carbon-burial process works, which means disturbing the seabed could have catastrophic consequences, potentially causing a severe decline in biodiversity and accelerating the impact of climate change.
The term “mining” is used to describe this activity, but it doesn’t really work like mining on dry land. On the seabed, it would involve a superficial extraction of minerals over a large area rather than digging down in a small region.
At the moment, no commercial deep-sea mining is allowed outside the exclusive economic zones of coastal nations. The International Seabed Authority (ISA, the UN governing body for this activity) is still writing the regulations to control the extraction of deep-sea minerals in international waters. However, the Pacific Island of Nauru has triggered the “two-year rule” after notifying ISA of its intention to start deep-sea mining. This means the ISA now has two years to complete regulations for deep-sea mining or, at least, to evaluate this particular proposal.
“Seabed mining is sometimes presented as an unavoidable consequence of ever-growing demand for minerals, especially to supply certain metals for the green technology transition,” said Dr Kirsten Thompson, based at the University of Exeter. “This narrative is put forward by mining companies, who also present deep-sea mining as the ‘lesser of two evils’ in comparison to land-based mining, but it’s impossible to compare the inherent value of land and deep-sea ecosystems. If you’re asking ‘which destructive industry is better?’ then you’re asking the wrong question.”
The Exeter team defended that there are too many uncertainties around deep-sea mining, and it would be better to look at alternatives. This could include, for example, developing more effective recycling procedures of elements from electronic waste as well as using more abundant compounds instead of metals in short supply. “It’s vital to bust the myth that we have no choice but to permit commercial mining in the deep sea,” said Dr Thompson.
Dangerously, the study highlights that deep-sea mining would most likely only benefit a handful of companies in the wealthiest countries, without much regard for future generations. As an attempt to avoid this, the team suggested a “Rights of Nature” management process to include marine researchers and local communities to become guardians of the sea.
“Once started, deep-sea mining is likely to be impossible to stop. Once lost, biodiversity will be impossible to restore”, concluded the researchers. “We mine our oceans at our peril.”
(1) Miller K, Bridgen K, Santillo D, Currie D, Johnston P and Thompson K (2021) Challenging the Need for Deep Seabed Mining From the Perspective of Metal Demand, Biodiversity, Ecosystems Services, and Benefit Sharing. Front. Mar. Sci., https://doi.org/10.3389/fmars.2021.706161