Deep-sea mining

DEEP-SEA MINING

Microbes drawn from the seabed may defeat drug-resistant infections. Yet those same depths are now prized for the metals they hold.

A
AGeological surveys suggest that the seabed holds greater quantities of nickel, cobalt and rare-earth elements than every land deposit put together. Companies hoping to mine it argue that reaching for these underwater reserves would broaden the sources from which such metals are drawn, and they stress how sharply demand is climbing — for copper, for aluminium, and above all for the lithium and cobalt that electric-vehicle batteries and consumer electronics consume in ever greater volumes. Ore hauled from the ocean floor, they claim, would be richer than anything dug on land and would leave behind almost no residue. Techniques vary, but nearly all of them adapt equipment once built for mining on land: material is cut loose thousands of metres down, a slurry of rock and seawater is pumped up to waiting ships, ‘de-watered’, and passed to a second vessel, while the drained seawater is sent back to the depths and released near the seabed.
B
BWhen Dr Tomás Valente watched a microbe taken from a deep-sea sponge wipe out disease-causing bacteria in his laboratory, he sensed he might be looking at a weapon against the antibiotic-resistant ‘superbugs’ that kill many thousands of people across Europe each year. The bacterium had been living more than 900 metres down in the Setúbal canyon, off the Iberian coast, and later tests showed that the antibiotic it produced was one science had never recorded — a finding that only sharpened its promise as a future medicine. Valente is one of a number of researchers who look on the deep ocean, with its countless unstudied and often unnamed species, as fertile ground for new drugs; and it is exactly this promise, they fear, that will be thrown away if the scramble for the sea’s metals and minerals is allowed to race ahead.
C
C‘What we’re really asking,’ says Valente, a marine pharmacologist at the Atlantic Biomedical Institute in Lisbon, ‘is whether more medicines are waiting down there, and whether we can reach them before the place is ruined for good.’ He is among the many scientists calling for deep-sea mining to be halted while its costs and benefits are properly weighed. Handled this way, he suggests, the sea’s living riches might prove worth far more than its ores. The oceans, he points out, blanket close to three-quarters of the planet and remain barely charted; craft steered from the surface keep turning up creatures no one has catalogued — sea stars that drift on stalked fins, or the pale ‘ghost’ jellyfish filmed some 3,500 metres beneath the Coral Sea — any of which might one day save lives. By his reckoning a newly found antibiotic may need a decade to become an approved treatment, yet the contest to mine the ocean deep is already under way.
D
DRecent research — among it a study in the journal Marine Frontiers — indicates that the deep seabed, and the hydrothermal vents that form wherever seawater seeps down and meets volcanic magma, matter enormously for marine biodiversity and for the world’s climate alike. Clustered around these mineral-laden vents live shrimp, tubeworms, mussels, limpets and eyeless crabs. Mining, the study warns, would throw up vast plumes of sediment and pour waste back into the water, badly unsettling the seafloor, and it concludes that the practice ‘endangers functions the seabed cannot do without’. Dr Rowan Whitfield, of the Marine Science Institute in Wellington, sums up the scientific mood plainly: ‘On the vents themselves, researchers speak with one voice — none of us wants them mined.’
E
EEnvironmental campaigners and legal experts, for their part, urge restraint, warning that the fallout for ocean life and for coastal communities could be enormous and is largely unknown — and that no agreed set of international rules yet governs how the seabed may be exploited. In one much-quoted paper, Naledi Mokoena and Farid Haddad of the Ocean Justice Initiative, writing with Dr Wei Lin of the Institute for Marine Governance in Kiel, argue that this ‘new gold rush beneath the waves’ merely repeats the old story of resource grabs: scant regard for the damage done to nature or society, and the pushing aside of indigenous peoples. So little is known of the deep seabed, they add, that the far side of the Moon, the plains of Mars, even the surface of Mercury have been mapped in sharper detail — a gap that leads them to call the deep ocean a place where ‘we still cannot say what it is we are missing.’
F
FThe seas remain vast and, for the most part, a mystery, notes Renata Kovač, chief executive of AbyssMetals, a deep-water prospecting firm in Vancouver: ‘It is only sensible to tap that unused potential responsibly, rather than keep leaning on the planet’s dwindling supplies of land-based ore to meet what society demands.’ Those pressing to lower mining machines far beneath the surface insist the harm will be slighter than what mining does on land. Critics reply that strange, little-understood communities in the deep could be obliterated and must be shielded. ‘No human undertaking has ever struck deep-sea life as hard as this one will,’ argues Professor Ingrid Halvorsen, a specialist in hydrothermal vents at the University of Tasmania, who holds that active vents ought to be placed entirely out of bounds — to protect the discoveries and biotechnology they may yet yield — with strict limits enforced everywhere else.

Question 1 - 4

Which paragraph contains the following information?

a mention of the steeply rising demand for a single material needed by the vehicle-manufacturing sector

an approximate figure for how much of the planet’s surface the seas take up

a note that nations have still not settled on shared regulations for working the ocean floor

an explanation of the way a mineral-rich deep-sea environment comes into being

a mention of the steeply rising demand for a single material needed by the vehicle-manufacturing sector

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