Mining’s next frontier is proving tricky to navigate. Last week a British company became the latest firm to announce its intention to mine the seabed. However, it is still unclear how deep-sea mining will affect the oceans.
UK Seabed Resources, a subsidiary of the aerospace and defence firm Lockheed Martin, will be exploring a 58,000-square-kilometre area of the Pacific Ocean. The company wants to use autonomous and remotely operated machines to collect polymetallic nodules, which can be rich in copper, nickel, manganese and rare earth minerals.
The company says mining the seabed for nodules is “ecologically sound“. But experts say we don’t know that yet.
Some areas of the seabed are ecologically unique, so disturbing them could be disastrous, says Euan Harvey of the University of Western Australia in Crawley. He says companies should do controlled experimental mining to study how the ecosystem recovers.
However, Charitha Pattiaratchi, also at the University of Western Australia, is cautiously hopeful. He says organisms that live on deep seabed are very rugged, having evolved under high pressure with no light, and in sediment that is regularly disturbed by violent storms. Pattiaratchi has studied the effects of active drilling by oil rigs on seabed communities at shallower depths. A month after drilling ended, wildlife had recovered to the point that he could not distinguish areas that were drilled from areas that were not.
There are other potential risks, says Joanna Parr of the Commonwealth Scientific and Industrial Research Organisation in Sydney, Australia. For instance, mining could change the behaviour of ocean currents by altering the seabed’s topography.